47 results on '"Common-mode signal"'
Search Results
2. Common mode voltage reduction of cascaded multilevel inverters using carrier frequency modulation
- Author
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Vinh-Quan Nguyen and Quang-Tho Tran
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Reduction (complexity) ,Carrier signal ,Total harmonic distortion ,Materials science ,Quality (physics) ,Modulation ,Electronic engineering ,Common-mode signal ,Electrical and Electronic Engineering ,Voltage - Abstract
Cascaded multilevel inverters have been increasingly used in industrial applications. However, the quality of the output voltage of these inverters depends highly on the modulation techniques. One ... more...
- Published
- 2021
- Full Text
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3. Tunable balanced liquid crystal phase shifter based on spoof surface plasmon polaritons with common-mode suppression
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Chang Ding, Tao Jin, Fanyi Meng, Qun Wu, Jian-Feng Lv, and Huilin Mu
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Materials science ,010405 organic chemistry ,business.industry ,Phase (waves) ,Physics::Optics ,02 engineering and technology ,General Chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,Surface plasmon polariton ,0104 chemical sciences ,Liquid crystal ,Optoelectronics ,General Materials Science ,Common-mode signal ,0210 nano-technology ,business ,Phase shift module ,Microwave - Abstract
In this paper, a novel design approach for microwave tunable balanced phase shifters with the common-mode (CM) suppression is proposed based on the liquid crystal (LC) technology. The proposed tuna... more...
- Published
- 2020
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4. A novel photovoltaic inverter topology based on common mode current suppression
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Qinlin Zhu, Yilong Cao, Youhua Jiang, and Fangping Zhao
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Computer science ,business.industry ,Photovoltaic system ,Photovoltaic inverter ,Electrical engineering ,Common-mode signal ,Topology (electrical circuits) ,Electrical and Electronic Engineering ,Current (fluid) ,business ,Computer Science::Distributed, Parallel, and Cluster Computing - Abstract
Aiming at the problems of large leakage current and low efficiency of existing transformerless single-phase grid-connected photovoltaic inverters, a novel transformerless single-phase grid-connecte... more...
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- 2020
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5. An Efficient Carrier-Based Modulation Strategy for Five-Leg Indirect Matrix Converters to Drive Open-End Loads with Zero Common-Mode Voltage
- Author
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Van Van Huynh, Quoc-Hoan Tran, Tuyen D. Nguyen, and Van-Thanh Dao
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Physics ,020209 energy ,Mechanical Engineering ,020208 electrical & electronic engineering ,Zero (complex analysis) ,Energy Engineering and Power Technology ,02 engineering and technology ,Matrix converters ,Topology ,Modulation ,0202 electrical engineering, electronic engineering, information engineering ,Common-mode signal ,Electrical and Electronic Engineering ,Space vector modulation - Abstract
This paper presents an efficient carrier-based modulation (CBM) strategy for a five-leg indirect matrix converter (IMC) to drive a three-phase open-end load (OEL) with approximate zero common-mode ... more...
- Published
- 2019
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6. Novel microwave balanced bandpass filter with high common mode rejection ratio and wide rejection band under common mode operation
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Jose-Luis Olvera-Cervantes, Alonso Corona-Chavez, Miguel-Antonio Romero-Ramirez, and Tejinder Kaur
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010302 applied physics ,Physics ,General Physics and Astronomy ,020206 networking & telecommunications ,02 engineering and technology ,Inductor ,01 natural sciences ,Electronic, Optical and Magnetic Materials ,Resonator ,Common-mode rejection ratio ,Band-pass filter ,Filter (video) ,0103 physical sciences ,0202 electrical engineering, electronic engineering, information engineering ,Electronic engineering ,Common-mode signal ,Electrical and Electronic Engineering ,Microwave - Abstract
In this work, a new balanced band pass filter and its design procedure are proposed. The filter is based on a novel resonator, named LTLC resonator, which consists of two inductors (L), two Transmi... more...
- Published
- 2019
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7. Common Mode Voltage Reduction Using 3D-SVPWM for 3-level CI-NPC Inverter with Hybrid Energy System
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Palanisamy Ramasamy and Vijayakumar Krishnasamy
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Physics ,Mechanical Engineering ,020208 electrical & electronic engineering ,Photovoltaic system ,Energy Engineering and Power Technology ,State vector ,02 engineering and technology ,Inductor ,Reduction (complexity) ,Control theory ,Harmonics ,0202 electrical engineering, electronic engineering, information engineering ,Inverter ,020201 artificial intelligence & image processing ,Common-mode signal ,Electrical and Electronic Engineering ,Pulse-width modulation - Abstract
This paper elucidates Common Mode Voltage (CMV) reduction in transformerless 3-phase 3-level Coupled Inductor Neutral Point (CI-NPC) Clamped Inverter with Hybrid Energy System. The three dimensional Space Vector Pulse Width Modulation (3D-SVPWM) with Nearest State Vector (NSV) is implemented to reduce the CMV by proper selection of medium, large and small vectors in 3D cubic space region. This NSV scheme in addition to CMV reduction, reduces the capacitor voltage balancing issues and minimizes switching losses. The proposed control provides full utilization of dc link voltage with reduced harmonics. This 3-level CI-NPC inverter is energized by hybrid energy source which includes photovoltaic system and wind energy system. The results obtained for the proposed scheme through simulation and experimental setup is compared with the conventional 2D-SVPWM and 3D-SVPWM scheme. From the compared results it is evident that the proposed scheme reduces CMV to a larger extent than 2D and 3D-SVPWM control. The... more...
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- 2018
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8. Direct model-based predictive control scheme without cost function for voltage source inverters with reduced common-mode voltage
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Sangshin Kwak, Jae-Chang Kim, and Sung-Ki Moon
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Engineering ,business.industry ,020209 energy ,020208 electrical & electronic engineering ,02 engineering and technology ,Model predictive control ,Mesh analysis ,Control theory ,0202 electrical engineering, electronic engineering, information engineering ,Common-mode signal ,Voltage droop ,Voltage regulation ,Voltage source ,Electrical and Electronic Engineering ,business ,Voltage reference ,Voltage - Abstract
This paper presents a direct model-based predictive control scheme for voltage source inverters (VSIs) with reduced common-mode voltages (CMVs). The developed method directly finds optimal vectors without using repetitive calculation of a cost function. To adjust output currents with the CMVs in the range of –Vdc/6 to +Vdc/6, the developed method uses voltage vectors, as finite control resources, excluding zero voltage vectors which produce the CMVs in the VSI within ±Vdc/2. In a model-based predictive control (MPC), not using zero voltage vectors increases the output current ripples and the current errors. To alleviate these problems, the developed method uses two non-zero voltage vectors in one sampling step. In addition, the voltage vectors scheduled to be used are directly selected at every sampling step once the developed method calculates the future reference voltage vector, saving the efforts of repeatedly calculating the cost function. And the two non-zero voltage vectors are optimally all... more...
- Published
- 2017
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9. A low-cost 4.9 GHz balanced bandpass filter with good common mode isolation
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Tamasi Moyra, Dwipjoy Sarkar, and Priyansha Bhowmik
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Physics ,Band-pass filter ,020208 electrical & electronic engineering ,Electronic filter topology ,0202 electrical engineering, electronic engineering, information engineering ,Electronic engineering ,General Physics and Astronomy ,020206 networking & telecommunications ,Common-mode signal ,02 engineering and technology ,Isolation (database systems) ,Electrical and Electronic Engineering ,Electronic, Optical and Magnetic Materials - Published
- 2017
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10. Direct Torque Control of Induction Motor with Common-Mode Voltage Elimination
- Author
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Yogesh N. Tatte and Mohan V. Aware
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Braking chopper ,Engineering ,Vector control ,business.industry ,020209 energy ,Mechanical Engineering ,020208 electrical & electronic engineering ,Energy Engineering and Power Technology ,02 engineering and technology ,Direct torque control ,Control theory ,0202 electrical engineering, electronic engineering, information engineering ,Inverter ,Common-mode signal ,Torque ripple ,Electrical and Electronic Engineering ,business ,Induction motor ,Voltage - Abstract
If the common-mode voltage in the induction motor drive is not eliminated, it may cause failure of motor bearings and malfunctioning of the electrical equipment associated with the drive. This article proposes the modified direct torque control technique to control the induction motor fed by three-level inverter, commonly called a neutral-point-clamped inverter. The selective voltage vectors in three-level inverter determine elimination of the common-mode voltage. The classic three-level direct torque control based on selection of 6-full, 6-half, and 2-zero voltage vectors out of available 27 is modified so that the 6-intermediate voltage vectors and a zero voltage vector are employed. A comparative investigation with another three-level direct torque control method which reduces both common-mode voltage and torque ripple is also carried out. These methods are compared with classic two-level direct torque control method in context of common-mode voltage, torque ripple, current total harmonic disto... more...
- Published
- 2016
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11. Analysis and procedure to design differential wideband filters with high-selectivity and high common-mode suppression
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José Luis Olvera-Cervantes, Alonso Corona-Chavez, and Elizabeth Cruz-Perez
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Computer science ,020208 electrical & electronic engineering ,Bandwidth (signal processing) ,General Physics and Astronomy ,020206 networking & telecommunications ,02 engineering and technology ,Microstrip ,Electronic, Optical and Magnetic Materials ,Common-mode rejection ratio ,Band-pass filter ,Control theory ,0202 electrical engineering, electronic engineering, information engineering ,Electronic engineering ,Prototype filter ,Common-mode signal ,Electrical and Electronic Engineering ,Wideband ,Passband - Abstract
This paper proposes a new structure to design differential wideband bandpass filters by cascading two different types of wideband bandpass filters. Detailed analysis to obtain the equations for designing differential filters with high selectivity and fractional bandwidths between 20 and 55% is presented. To complement the equations a design methodology is proposed and two prototypes with different bandwidth are designed, simulated, and fabricated. The measurement results under differential mode show that the designed filters present two transmission zeros, constant insertion losses, return losses greater than dB and a stop band of at least 2.5. On the other hand, the common-mode signals are suppressed below dB in the whole passband. more...
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- 2016
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12. Wideband balanced networks with wideband common mode suppression and arbitrary power-dividing ratio
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Wenjie Feng, Wenquan Che, Zhao Chaoying, and Xin Gao
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Physics ,020208 electrical & electronic engineering ,Phase (waves) ,General Physics and Astronomy ,020206 networking & telecommunications ,02 engineering and technology ,Variable-Rate Multimode Wideband ,Topology ,Electronic, Optical and Magnetic Materials ,law.invention ,Power (physics) ,Planar ,law ,Control theory ,0202 electrical engineering, electronic engineering, information engineering ,Equivalent circuit ,Common-mode signal ,Electrical and Electronic Engineering ,Resistor ,Wideband - Abstract
Two novel wideband balanced networks with wideband common mode suppression and arbitrary power-dividing ratio are proposed in this paper. The differential/common mode equivalent circuits of the balanced networks can be easily reduced based on the matrix transformation. Microstrip-slotline 180° phase inverters loaded with four isolation resistors are used to realize high isolation for the power division output ports. Two planar wideband equal and unequal power division balanced networks with bandwidths of 33% of (1:1, equal) and 39% (1:2.22, unequal) for the differential mode and over 120% common mode suppression (0.96–3.6 GHz, |Scc21, 31 more...
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- 2016
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13. Experimental investigation and analysis of EMI in stacked I/O connectors of PCB
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Hsi-Hsir Chou and Y.-S. Lee
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Materials science ,Computer simulation ,business.industry ,Acoustics ,020208 electrical & electronic engineering ,General Physics and Astronomy ,020206 networking & telecommunications ,02 engineering and technology ,Electromagnetic interference ,Electronic, Optical and Magnetic Materials ,Noise ,EMI ,0202 electrical engineering, electronic engineering, information engineering ,Common-mode signal ,Electrical and Electronic Engineering ,Noise level ,Telecommunications ,business - Abstract
The electromagnetic interference (EMI) caused by the noise resulting from a common mode of stacked I/O connectors is analyzed using both numerical simulation and experimental measurements. The use of stacked connectors exists on the PCBs of today’s information technology equipment in order to reduce size; however, size reductions will cause increased severe EMI. After diagnosis and analysis, a strategy is presented to suppress the EMI noise level, as well as its emissions, and is found to be very effective as shown by our experiments. more...
- Published
- 2015
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14. Speed enhancement and kickback noise reduction in single-stage latched comparator improved for high-speed and low-noise analogue-to-digital converters
- Author
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E. Haghighi, Sarang Kazeminia, Obalit Shino, and Khayrollah Hadidi
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Comparator ,Input offset voltage ,Computer Networks and Communications ,Computer science ,business.industry ,Noise reduction ,020208 electrical & electronic engineering ,Electrical engineering ,020206 networking & telecommunications ,02 engineering and technology ,Converters ,Electronic, Optical and Magnetic Materials ,Comparator applications ,Control theory ,0202 electrical engineering, electronic engineering, information engineering ,Digital control ,Common-mode signal ,Electrical and Electronic Engineering ,business ,Instrumentation ,Jitter - Abstract
In the proposed high-speed comparator, the common mode level of the output voltages is preserved unchanged during pre-amplification and latch operations to enhance the comparison speed. Second, in the proposed low-noise comparator, operations are scheduled by two reduced amplitude signals, around 0.6 V instead of 3.3 V, to alleviate the coupling noise of digital control signals. Simulation results confirm that a 5 mV input difference can be simply detected at 800 MS/s and 500 MS/s update rate, in high-speed and low-noise comparators, respectively. Hence, about 60% improvement is realised in speed of the conventional structure. Moreover, input-referred kickback is reduced from 12 mV to less than 100 µV in low-noise version. High-speed and low-noise comparators consume around 780 µW and 650 µW at maximum allowable update rate in 288 µm2 and 480 µm2 active areas, respectively. Applying 8 mV offset voltage on input devices of differential pair and 75 ps peak-to-peak jitter on control signals guarantee... more...
- Published
- 2015
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15. A Highly Efficient Single-phase Transformerless H-bridge Inverter for Reducing Leakage Ground Current in Photovoltaic Grid-connected System
- Author
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Nasrudin Abd Rahim, Wahidah Abd Halim, and Maaspaliza Azri
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Engineering ,business.industry ,Mechanical Engineering ,Photovoltaic system ,Electrical engineering ,Energy Engineering and Power Technology ,Hardware_PERFORMANCEANDRELIABILITY ,Grid ,Ground current ,Midpoint ,law.invention ,Capacitor ,Hardware_GENERAL ,law ,Hardware_INTEGRATEDCIRCUITS ,Electronic engineering ,Common-mode signal ,Electrical and Electronic Engineering ,business ,Voltage ,Leakage (electronics) - Abstract
In this article, the performance of the split-capacitor H-bridge topology as a single-phase transformerless photovoltaic inverter is studied. By connecting the midpoint of its two series DC-link capacitors to the ground, the split-capacitor H-bridge is able to clamp the common-mode voltage of the system, effectively suppressing leakage ground current. To overcome the issue of capacitor voltage balancing, a simple balancing circuit and its control are introduced. The operation modes, common-mode voltage, and leakage ground current characteristics of the split-capacitor H-bridge topology are discussed, subsequently validated using both simulation and experimental tests. Comparison with a conventional transformerless H-bridge topology proves the superiority of the split-capacitor H-bridge topology in terms of leakage ground current and efficiency. more...
- Published
- 2015
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16. An Ultra-Low Phase Noise CMOS VCO Design Technique for Mobile Applications
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Nam-Jin Oh
- Subjects
Resonator ,GSM frequency bands ,Voltage-controlled oscillator ,CMOS ,business.industry ,Computer science ,Phase noise ,Electrical engineering ,Common-mode signal ,Electrical and Electronic Engineering ,Current source ,Inductor ,business - Abstract
This paper describes an ultra-low phase noise complementary metal-oxide semiconductor (CMOS) voltage-controlled oscillator (VCO) design technique targeted for GSM 900 and DCS 1800 base station (BTS) receiver, which require the toughest phase noise performance between 600 kHz and 3 MHz offset frequency. The proposed VCO suppresses the phase noise by three mechanisms; removes the current source, the main noise contributor in the VCO; includes double tuned resonators to prevent the switching pair from entering the triode region; filters out the second harmonic noise with a small size inductor at the common mode node of the VCO. The feasibility of the proposed VCO is verified using a 65 nm CMOS technology. Operating at around 3.6 GHz frequency range, the VCO is designed to meet the phase noise requirement of micro BTS and normal BTS. The proposed VCO consumes 27 mW dc power from a 0.7 V supply, and achieves the best figure-of-merit of −201dBc/Hz at 3 MHz offset. more...
- Published
- 2014
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17. VCMIPWM Scheme to Reduce the Neutral-Point Voltage Variations in Three-Level NPC Inverter
- Author
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V. Suresh Kumar and S. Nageswari
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Control theory ,Neutral point voltage ,Modulation index ,Inverter ,Common-mode signal ,Electrical and Electronic Engineering ,Field-programmable gate array ,Pulse-width modulation ,Three level ,Computer Science Applications ,Theoretical Computer Science ,Voltage ,Mathematics - Abstract
This paper presents variable common mode injection pulse width modulation (VCMIPWM) technique to reduce the neutral-point voltage variations in three-level neutral-point-clamped (NPC) inverter. The neutral-point voltage varies with the modulation index and the variation is high in the low modulation index region. Therefore, proper common mode voltages are calculated for various modulation index regions and are carefully injected with the reference phase voltages. The calculation is based on equalizing the switching times of the zero/redundant vectors in a switching cycle for various modulation index regions. The simulation results show the improvement in the neutral-point voltage balancing of the inverter in the VCMIPWM scheme compared with the sinusoidal pulse width modulation (PWM). The proposed PWM is implemented in field programmable gate array (FPGA) and the experimental results are shown to verify the practicability of the proposed method. more...
- Published
- 2014
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18. A double differential-mode current injection method based on directional couplers for HIRF verification testing of interconnected systems
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X.-D. Pan, X.-F. Lu, and G.-H. Wei
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Field (physics) ,Computer science ,business.industry ,General Physics and Astronomy ,Electronic, Optical and Magnetic Materials ,Electronic engineering ,Power dividers and directional couplers ,Common-mode signal ,Electrical and Electronic Engineering ,Current (fluid) ,Differential (infinitesimal) ,Telecommunications ,business ,HIRF ,Equivalence (measure theory) ,Software verification - Abstract
In this paper, a double differential-mode current injection (DDMCI) method is proposed to achieve the equivalence with high-level field radiation, when interconnected systems are under test. With t... more...
- Published
- 2013
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19. Modified Combined DTC and FOC Based Control for Medium Voltage Induction Motor Drive in SVM Controlled DCMLI
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Hiralal M. Suryawanshi, K.D. Kulat, Mohan M. Renge, and U. V. Patil
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Engineering ,Vector control ,business.industry ,Control (management) ,Control engineering ,Support vector machine ,Direct torque control ,Control theory ,Inverter ,Common-mode signal ,Electrical and Electronic Engineering ,business ,Induction motor ,Voltage - Abstract
Modified combined direct torque control (DTC) and field oriented control (FOC) based method is proposed in this paper to improve the performance of induction motor (IM) drive. The proposed method includes combined advantages of DTC and FOC schemes. An algorithm is developed for closed-loop control of the proposed control method and the scheme is implemented in space vector controlled five-level diode-clamped inverter. For this, an experimental prototype is developed to control three-phase, 3-hp IM drive. The comparative performance of proposed control method, DTC and FOC with experimental results in SVM controlled five-level inverter is presented to validate the effectiveness of the proposed control scheme. Also, the switching states are selected so as to control the inverter output voltage as well as reduce the common mode voltage (CMV) of the drive. more...
- Published
- 2013
- Full Text
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20. Prediction of radiated emissions from microstrip components for RF/microwave circuits using measurement of common-mode current
- Author
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Jian-Ming Wu, Chien-Hsiang Huang, Cheng-Yu Ho, Kai-Syuan Chen, and Tzyy-Sheng Horng
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Materials science ,Physics::Instrumentation and Detectors ,Acoustics ,Measure (physics) ,General Physics and Astronomy ,Microstrip resonators ,Microstrip ,Electronic, Optical and Magnetic Materials ,Microstrip antenna ,Common-mode signal ,Electrical and Electronic Engineering ,Current (fluid) ,Microwave ,Electronic circuit - Abstract
This work presents a novel method of using a vector network analyzer with a bulk current injection probe to measure the common-mode current of microstrip components in a RF/microwave circuit. Based on the proposed measurement, the far-field radiated emissions are determined, which correlate with measurements obtained in a fully-anechoic chamber. In this study, the proposed method is developed to determine the radiated emissions from a microstrip resonator and a microstrip bandpass filter. Full-wave electromagnetic simulations demonstrate the accuracy of the proposed measurement. more...
- Published
- 2013
- Full Text
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21. High selectivity and common-mode suppression combline balanced BPF
- Author
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Yong-Jiu Zhao, Hong-Wei Deng, Ying He, Yong Fu, and Xiao-jun Zhou
- Subjects
Physics ,High selectivity ,General Physics and Astronomy ,Stopband ,Topology ,Electronic, Optical and Magnetic Materials ,Resonator ,Coupling (computer programming) ,Control theory ,Filter (video) ,Microstrip bandpass filter ,Insertion loss ,Common-mode signal ,Electrical and Electronic Engineering - Abstract
In this study, new balanced microstrip bandpass filter (BPF) based on stepped-impedance combline structure is proposed with high selectivity and high common-mode (CM) suppression performance In the beginning, a single-ended compact stepped-impedance resonator (SIR) combline BPF with enhanced performance including low insertion loss, sharp skirt and wide stopband response is designed by consisting of an array of short quarter-wavelength bi-section SIRs with a new scheme of tapped-transformer coupling at input and output ports. Under CM excitation, no special consideration or design procedure is required to suppress the CM, and the CM suppression is the nature of the parallel-coupled filter. Finally, the second- and third-order SIR combline balanced BPFs for WLAN application, without loss of generality, have been designed and implemented. The simulated and measured results show a good agreement and validate the proposed theory. more...
- Published
- 2013
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22. Prediction of common-mode radiated emission from PCB using vector network analyzer with a bulk injection current probe
- Author
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Kai-Syuan Chen, Cheng-Yu Ho, and Tzyy-Sheng Horng
- Subjects
Physics ,Printed circuit board ,Acoustics ,Measure (physics) ,General Physics and Astronomy ,Common-mode signal ,Transmission coefficient ,Electrical and Electronic Engineering ,Current (fluid) ,Electromagnetic simulation ,Radiated emission ,Electronic, Optical and Magnetic Materials - Abstract
This paper uses the vector network analyzer with a bulk injection current probe to measure the transmission coefficient for the common-mode radiated emissions from a printed circuit board. The purpose of developing such a measurement technique is to predict the far-field spectrum of radiated emission for good correlation with the fully-anechoic chamber measurement results. Electromagnetic simulation is also applied to verify the accuracy of the proposed technique. Comparison between simulation and measurement shows rather satisfactory agreement. more...
- Published
- 2012
- Full Text
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23. A novel method of common-mode voltage reduction in matrix converters
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Tae-Won Chun, Hoang M. Nguyen, and Hong-Hee Lee
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Reduction (complexity) ,Control theory ,Harmonic ,Waveform ,Common-mode signal ,Power factor ,Electrical and Electronic Engineering ,Space (mathematics) ,Space vector modulation ,Mathematics ,Voltage - Abstract
This article proposes a novel direct space vector modulation (DSVM) strategy that can restrict the common-mode voltage of a three-phase-to-three-phase matrix converter and maintain sinusoidal input/output waveforms, as well as a unity power factor at the input side. The proposed control method has been developed using active, non-zero space vectors instead of zero space vectors. A new space vector modulation table is also presented with the space vector rearrangement. One advantage of the proposed method is a 42% reduction of the peak value of the common-mode voltage besides the lower harmonic components compared to the conventional DSVM method. Furthermore, the maximum voltage transfer ratio is unaffected by the proposed method. Simulation and experimental results are shown to validate the advantages of the proposed DSVM method. more...
- Published
- 2012
- Full Text
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24. Balanced Dual-Band BPF using only Equal-Electric-Length SIRs for Common-Mode Suppression
- Author
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Hsun-Hsiang Chen, Ching-Her Lee, Chung-I G. Hsu, and C.-C. Hsu
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Physics ,Resonator ,Transmission (telecommunications) ,Band-pass filter ,Control theory ,General Physics and Astronomy ,Common-mode signal ,Multi-band device ,Electrical and Electronic Engineering ,Topology ,Electronic, Optical and Magnetic Materials - Abstract
This paper presents a new balanced dual-band bandpass filter (BPF) designed for 2.4/5.2 GHz wireless local area networks (WLANs). Because adopted in the BPF are only bi-section equal-electric-length stepped-impedance resonators (SIRs), whose dimensions can be determined using analytic formulas, the BPF can be easily and efficiently designed. The inner SIRs are designed to resonate only at the odd-mode resonant frequencies of the input and output SIRs but not at the even-mode ones. This leads to well-behaved differential-mode (DM) transmission and excellent common-mode (CM) suppression for the BPF. Simulated and measured results are found to agree quite well to each other. The measured minimum DM insertion losses in the two passbands are 2.1 and 2.54 dB, whereas the measured CM rejections are higher than 33 dB in the frequency range from 1 to 7 GHz. more...
- Published
- 2010
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25. Dual-Feed Cavity-Backed Slot Antennas
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Zhongxiang Shen, Y. L. Guan, and M. Zhang
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Physics ,High-gain antenna ,Distribution networks ,business.industry ,Acoustics ,Bandwidth (signal processing) ,General Physics and Astronomy ,Slot antenna ,Radiation ,Electronic, Optical and Magnetic Materials ,Common-mode signal ,Electrical and Electronic Engineering ,Telecommunications ,business ,Excitation - Abstract
This paper is concerned with dual-feed cavity-backed slot antennas operating at 2.4 GHz. Two modes of excitation are considered for the dual-feed antennas: pseudo-differential feed and common mode feed. Four configurations are described for these two modes excited at the same side or the opposite sides of the slot. With the use of a carefully designed power distribution network, dual-feed slot designs are realized for a wide bandwidth, high gain, and symmetric radiation patterns. Measured results are in good agreement with simulated ones. more...
- Published
- 2010
- Full Text
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26. Reduction of Common Mode Currents Generated by Three-Level Inverters with Consideration of Motor Overvoltages
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Nadir Idir, Philippe Le Moigne, J.J. Franchaud, Jacques Ecrabey, Philippe Baudesson, and Arnaud Videt
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Reduction (complexity) ,Engineering ,Control theory ,business.industry ,Inverter ,Common-mode signal ,Adjustable-speed drive ,Electrical and Electronic Engineering ,Degrees of freedom (mechanics) ,business ,Pulse-width modulation ,Three level - Abstract
In adjustable speed drive applications, the switching of the inverter semiconductors generates common mode currents as well as harmful overvoltages on the motor terminals when long cables are used. Consequently, bulky and expensive input and output filters must be used. This work aims at reducing these disturbances from their origin by using a three-level neutral-point-clamped (NPC) inverter controlled with a new pulse-width-modulation (PWM) strategy. Whereas previous common mode noise-reducing strategies usually generate higher overvoltages than conventional ones, the proposed PWM is able to manage both problems thanks to its internal degrees of freedom. more...
- Published
- 2009
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27. Performance Characteristics of the Reduced Common Mode Voltage Near State PWM Method
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E. Un and Ahmet M. Hava
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Physics ,Mesh analysis ,Control theory ,Overvoltage ,Ripple ,Linearity ,Common-mode signal ,Electrical and Electronic Engineering ,Polarity (mutual inductance) ,DC-BUS ,Pulse-width modulation ,Voltage - Abstract
The Near State PWM (NSPWM) method, which has low common mode voltage/current is proposed for three-phase voltage source inverter drives. The method is described and its voltage linearity, output current ripple, DC bus current ripple, common mode voltage and output line-to-line pulse patterns are thoroughly studied and compared with classical PWM methods. The theory, simulation, and laboratory experiments illustrate that NSPWM has low common mode voltage, results in less common mode current, has low switching losses comparable to those of DPWM methods, has low current ripple compared to the classical methods, and exhibits no significant overvoltage problems in long cable applications as its pulse pattern involves a sufficient distance between the polarity reversing voltage pulses. more...
- Published
- 2009
- Full Text
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28. A DC-Link Capacitor Voltage Balancing with CMV Elimination Using Only the Switching State Redundancies for a Reduced Switch Count Multi-Level Inverter Fed IM Drive
- Author
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K. Gopakumar, Anandarup Das, F Sheron, Gopal Mondal, and K. Sivakumar
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Engineering ,Modulation ,business.industry ,Control theory ,Inverter ,Common-mode signal ,State (computer science) ,Electrical and Electronic Engineering ,business ,Induction motor ,Pulse-width modulation ,Power (physics) ,Voltage - Abstract
Common mode voltage (CMV) variations in PWM inverter-fed drives generate unwanted shaft and bearing current resulting in early motor failure. Multilevel inverters reduce this problem to some extent, with higher number of levels. But the complexity of the power circuit increases with an increase in the number of inverter voltage levels. In this paper a five-level inverter structure is proposed for open-end winding induction motor (IM) drives, by cascading only two conventional two-level and three-level inverters, with the elimination of the common mode voltage over the entire modulation range. The DC link power supply requirement is also optimized by means of DC link capacitor voltage balancing, with PWM control., using only inverter switching state redundancies. The proposed power circuit gives a simple power bits structure. more...
- Published
- 2009
- Full Text
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29. Carrier-based modulation strategies for a neutral point clamped inverter
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Muhammad Jamil
- Subjects
Engineering ,business.industry ,Modulation ,Control theory ,Harmonics ,Phase (waves) ,Harmonic ,Inverter ,Common-mode signal ,Electrical and Electronic Engineering ,business ,Diode ,Voltage - Abstract
This article presents carrier-based modulation strategies for a neutral point clamped inverter that substantially reduces harmonics in the output line to line voltages, phase voltages, reference voltages and common mode voltage. A graphical technique that has already been proposed in the literature and that also allows various carrier disposition modulation strategies for a diode clamped inverter is being described here. For this graphical technique two new modulation strategies – alternative phase opposite disposition (APOD) and phase disposition (PD) – are being used to create reduced harmonics for diode-clamped inverters under both continuous and discontinuous switching conditions. These strategies can be further expanded in a very simple way. A comparison of conventional-, APOD- and PD-strategies will be given by simulation results by using the software ‘Simplorer’ and ‘Post Processor Day’. The common mode voltage has been reduced particularly with PD-strategy. The strategies have been confirmed using... more...
- Published
- 2008
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30. High-speed low-power CMOS comparator dedicated to 10 bit 20 MHz pipeline ADCs for RF WLAN applications
- Author
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M.T. Belaroussi, Abdelhalim Slimane, L. Bouzerara, M.B. Guermaz, and B. Lehouidj
- Subjects
Engineering ,Input offset voltage ,Comparator ,business.industry ,Electrical engineering ,Operational amplifier applications ,Propagation delay ,Switched capacitor ,Comparator applications ,CMOS ,Electronic engineering ,Common-mode signal ,Electrical and Electronic Engineering ,business - Abstract
This article describes and analyses a low power and high speed comparator. The designed comparator is intended to be implemented in a 10 bit 20 MHz Pipeline Analogue-to-Digital Converter dedicated to RF Wireless Local Area Network (WLAN) applications. This comparator is based on the switched capacitor network using a two-phase non-overlapping clock. The offset voltage of the designed comparator has been reduced by means of an active positive feedback. The analyses and simulation results which have been obtained using 0.8 µm CMOS AMS process parameters, with a power supply voltage of 5 V and an input common mode of 2–3 V, show that this comparator exhibits a propagation delay of 17.3 ns, an offset voltage of about 77.3 mV, a good accuracy and a low power consumption of about 0.8 mW. The predicted performance is verified by analyses and simulations using PSPICE tool. more...
- Published
- 2008
- Full Text
- View/download PDF
31. HF Model of an Unshielded 2-Wire Energy Cable Submitted to Power Electronic Converter Constraints
- Author
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R. Bausiere, Y. Weens, J.J. Franchaud, and Nadir Idir
- Subjects
Engineering ,business.industry ,Mode (statistics) ,Electrical engineering ,Power (physics) ,Hardware and Architecture ,Mechanics of Materials ,EMI ,Modeling and Simulation ,Electronic engineering ,Common-mode signal ,Adjustable-speed drive ,Electrical and Electronic Engineering ,business ,Software ,Premature ageing ,Energy (signal processing) - Abstract
In adjustable speed drive applications operating at high switching frequencies, common mode and differential mode perturbations may cause premature ageing of electric machines and important electro... more...
- Published
- 2008
- Full Text
- View/download PDF
32. Five-Level Inverter Topology for Induction Motor Drives with Common-Mode Voltage Elimination in Complete Modulation Range
- Author
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R.S. Kanchan, P. N. Tekwani, K. Gopakumar, and Andrea Vezzini
- Subjects
Conducted electromagnetic interference ,Engineering ,Control theory ,business.industry ,Shaft voltage ,Inverter ,Grid-tie inverter ,Common-mode signal ,Electrical and Electronic Engineering ,business ,Pulse-width modulation ,Induction motor ,Voltage - Abstract
Common-mode voltage (CMV) generated by different topologies of the pulse width modulated (PWM) inverters causes shaft voltage, bearing current and ground leakage current in the induction motor (IM) drive system. Consequently the premature mechanical failure (fluting) of machine bearings and conducted electromagnetic interference (EMI) are observed in the multilevel PWM inverter fed IM drive systems. A five-level inverter topology with switching state combination selection strategy for PWM control is proposed for an IM drive for complete elimination of CMV in the entire operating range of the drive, including over-modulation. The proposed scheme is based on a dual five-level inverter fed open-end winding IM drive structure. Each individual five-level inverter of the proposed drive is formed by cascading a three-level neutral point clamped (NPC) inverter with two conventional two-level inverters. Hence, the proposed individual five-level inverter offers simple power-bus structure with less number of power diodes as compared to the conventional NPC five-level inverter. The proposed open-end winding IM drive structure requires nearly half the dc-link voltage and provides increased number of redundant switching state combinations as compared to a single five-level NPC inverter fed conventional IM drive. The proposed CMV elimination scheme is experimentally verified on a 1.5 kW openend winding IM drive. more...
- Published
- 2007
- Full Text
- View/download PDF
33. Preliminary results: a three coil balanced system for imaging steel bars behind steel boundaries
- Author
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Muhammad Zaid, Graham Miller, Patrick Gaydecki, and Bosco Fernandes
- Subjects
Digital signal processor ,Engineering ,business.industry ,Mechanical Engineering ,Acoustics ,Transmitter ,Electrical engineering ,General Physics and Astronomy ,Ranging ,Magnetic field ,law.invention ,Mechanics of Materials ,Electromagnetic coil ,law ,General Materials Science ,Common-mode signal ,business ,Transformer ,Sheet steel - Abstract
This paper describes preliminary results obtained from a modified transformer coupled system for detecting and imaging steel objects on the distal side of a ferrous steel boundary up to 2 mm thick, using a balanced three-coil system. Typically, it may be applied for the imaging of steel reinforcing bars embedded within concrete, which includes a sheet steel layer located between the bars and the upper surface of the concrete. A transmitter, receiver and a dummy coil are placed on the upper surface of the specimen and moved across it. The dummy coil is used to cancel the common mode signal (cross-talk) between the transmitter and receiver, thereby enhancing the signal emanating from the steel bars. By exciting the transmitter with signals ranging between 125 Hz and 1 kHz, it is possible to generate a magnetic field that is not severely attenuated by the sheet, enabling the detection of a ferrous target located below the sheet. In addition to signal cancellation, a real-time digital signal processor is empl... more...
- Published
- 2006
- Full Text
- View/download PDF
34. A Four-level Inverter Scheme with Reduced Common Mode Voltage for an Induction Motor Drive
- Author
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R.S. Kanchan, K. Gopakumar, P. N. Tekwani, and Baiju
- Subjects
Scheme (programming language) ,Engineering ,business.industry ,Power (physics) ,Amplitude ,Control theory ,Inverter ,Common-mode signal ,Grid-tie inverter ,Electrical and Electronic Engineering ,business ,computer ,Induction motor ,Voltage ,computer.programming_language - Abstract
A four-level inverter configuration for an induction motor is proposed in this paper. The drive used for this scheme is an open-end winding induction motor which can be obtained by separating the neutral connections of any general threephase induction motor. The proposed scheme uses two three-level inverters, with asymmetric DC link voltage, feeding the induction machine from both sides and can generate voltage space vector locations similar to a conventional seven-level inverter. The four-level scheme is based on the use of only those space vector combinations of the seven-level inverter, which generate zero common mode voltage in the machine phase voltages. The proposed four-level inverter scheme requires only two isolated DC links as compared to the conventional diode-clamped four-level inverter scheme, which needs three isolated power supplies. The common mode voltage, in the pole voltages of the proposed four-level inverter, is significantly lower than that of the conventional four-level inverter while the machine phase voltages have zero common mode content. The proposed power circuit bus structure is simple to fabricate when compared to the conventional four-level inverter. A SVPWM scheme is presented, which generates the inverter gate switching signals from sampled amplitudes of reference phase voltages. The proposed four-level inverter scheme is implemented of a 1.5 kW open-end winding induction motor and the experimental results are presented. more...
- Published
- 2005
- Full Text
- View/download PDF
35. Modelling and Minimizing of high Frequency Leakage Currents in Adjustable Speed Drives
- Author
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Nadir Idir and J.J. Franchaud
- Subjects
Engineering ,business.industry ,Capacitive sensing ,Bipolar junction transistor ,Electrical engineering ,Hardware and Architecture ,Mechanics of Materials ,Modeling and Simulation ,Hardware_INTEGRATEDCIRCUITS ,Electronic engineering ,Ball (bearing) ,Power semiconductor device ,Common-mode signal ,Electrical and Electronic Engineering ,business ,Software ,Leakage (electronics) - Abstract
Today, adjustable speed drives (ASDs) manufacturers use high-speed switching devices such as the insulated gate bipolar transistors (IGBTs) to achieve higher efficiency, low weight, and small size. However, the advent of fast power devices has produced several unexpected problems, such as premature deterioration of ball bearing and high levels of electromagnetic einissions, caused by flowing of parasitic capacitive currents known as common mode (CM) currents. In order to evaluate these leakage currents, a suitable model of the ASD is obtained by identification of the high-frequency spreading paths. The authors first carry out simulations using the proposed model and compare the results with experimental one. They then propose two methods of reduction of the CM currents in the ASD system. more...
- Published
- 2005
- Full Text
- View/download PDF
36. Reduction of Bearing Currents in Inverter Fed Drive Applications by Using Sequentially Positioned Pulse Modulation
- Author
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J. Zitzelsberger and Wilfried Hofmann
- Subjects
Physics ,Bearing (mechanical) ,Vector control ,law ,Control theory ,Modulation ,Inverter ,Common-mode signal ,Voltage source ,Electrical and Electronic Engineering ,Pulse-width modulation ,law.invention ,Voltage - Abstract
The phenomenon of bearing currents is known for a long period. Especially those which are caused by magnetic asymmetries have been investigated since the beginning of the 20th century Nowadays new kinds of bearing currents can be observed in inverter fed induction drives. Investigations done on these effects show that the switched operational mode – especially of voltage source inverters – causes a high frequency common mode voltage (CMV). This voltage supplies the common mode circuit of an electrical machine in which the bearings are a part oof. Therefore, to reduce the occurrence of bearing currents it is necessary to avoid or – at least – to minimise the common mode voltage in drive applications fed by voltage source inverters. A novel principle for such a purpose is the space vector based modulation with sequentially positioned pulses (SPP). With this modulation it is possible to reduce both the number of edges within the CMV and its amplitude to a great extent without influencing the modulati... more...
- Published
- 2004
- Full Text
- View/download PDF
37. A Space-Vector Modulation Scheme for a Dual Two-Level Inverter Fed Open-End Winding Induction Motor Drive for the Elimination of Zero-Sequence Currents
- Author
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Satyesh K. Sinha, E.G. Shivakumar, V. T. Somasekhar, and K. Gopakumar
- Subjects
Engineering ,business.industry ,Phasor ,law.invention ,law ,Control theory ,Harmonics ,Inverter ,Common-mode signal ,Electrical and Electronic Engineering ,Transformer ,business ,Space vector modulation ,Pulse-width modulation ,Induction motor - Abstract
The dual two level inverter fed open-end winding induction motor drive gives voltage space phasor locations similar to a three-level inverter fed induction motor drive. The dual inverter scheme renders advantages such as redundancy of the space vector combinations for the same number of space vector locations and the absence of neutral point fluctuations. In a dual inverter scheme, a total of 64 space vector combinations are distributed over 19 space vector locations compared to 27 space vector combinations distributed over the same number of locations in a three level inverter. The common mode voltages (the harmonics of the triplen order) need to be suppressed by transformer isolation or by the use of harmonic filters. In this paper, a space vector modulation scheme for the suppression of zero sequence currents (the harmonics of the triplen order) for a dual two level inverter fed open-end winding induction motor drive is described. The proposed scheme does not require bulky transformers or harmonic filters for the elimination of the zero sequence currents. The proposed space vector PWM is based on the observation that certain voltage space vector combinations in the dual inverter scheme do not contribute to the triplen harmonics and hence the PWM scheme that exclusively employs these combinations is used to eliminate the triplen harmonic currents more...
- Published
- 2002
- Full Text
- View/download PDF
38. Separating Common Mode and Differential Mode Noise in EMI Measurement
- Author
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R.W. De Doncker and A. Nagel
- Subjects
Differential mode noise ,Interference (communication) ,Computer science ,EMI ,Mode (statistics) ,Electronic engineering ,Common-mode signal ,Electrical and Electronic Engineering ,Differential (infinitesimal) ,Converters ,Power (physics) - Abstract
The separation of differential mode and common mode noise in EMI analysis is a well known procedure which is useful especially for the analysis and the understanding of interference phenomena of power converters. However, separating both components is rarely done during measurements. Therefore, two different approaches are developed and evaluated in this paper to realize separated common mode and differential mode measurements. more...
- Published
- 2000
- Full Text
- View/download PDF
39. NEUTRAL-TO-GROUND VOLTAGE MINIMIZATION IN A PWM-RECTIFIER / INVERTER CONFIGURATION
- Author
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Alexander L. Julian, Thomas A. Lipo, and A. M. De Broe
- Subjects
Engineering ,Bearing (mechanical) ,business.industry ,Electrical engineering ,PWM rectifier ,law.invention ,Rectifier ,law ,Inverter ,Common-mode signal ,Electrical and Electronic Engineering ,business ,Pulse-width modulation ,Induction motor ,Voltage - Abstract
High frequency common mode voltage produced by power converters are a major cause of conducted EMI, creating motor ground currents, bearing currents and other harmful by-products. In this paper a control algorithm for an induction motor fed by a fully controlled rectifier and inverter is developed to reduce the common mode neutral-to-ground voltage of the induction motor. A bearing current model is used to evaluate the effects on the bearing currents of the double bridge modulation scheme when the new algorithm and conventional algorithms are used. Simulation results are shown to demonstrate the benefits of the new PWM approach. more...
- Published
- 1998
- Full Text
- View/download PDF
40. A novel approach to common mode gain in differential amplifiers
- Author
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Victor Marin Contreras
- Subjects
Engineering ,Common-mode rejection ratio ,Control theory ,business.industry ,Mode (statistics) ,Electronic engineering ,Differential amplifier ,Common-mode signal ,Method of analysis ,Electrical and Electronic Engineering ,Differential (infinitesimal) ,business - Abstract
The analysis of common mode behaviour in monolithic active loaded differential amplifiers has been a complicated task that is beyond simplified models, and therefore designers have left it to simulation programs. A new and simpler method of analysis is presented in which the circuit is divided in two parts which are analysed separately. Calculations are notably simplified and a reasonable accuracy is obtained. Furthermore, the influences of finite offsets on common mode and differential mode gains are determined. The proposed method is illustrated with a practical circuit, which is simulated using PSPICE. more...
- Published
- 1998
- Full Text
- View/download PDF
41. Microsecond Time Synchronisation between GMRT, Pune and NPL, New Delhi using INSAT Standard Time and Frequency Broadcast in a Differential Mode
- Author
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A. Sen Gupta, B.S. Mathur, A.K. Hanjura, Gaurav Goel, and M R Sankararaman
- Subjects
Physics ,Giant Metrewave Radio Telescope ,business.industry ,Standard time ,Electrical engineering ,Standard time and frequency signal ,Residual ,Global Positioning System ,Time transfer ,Common-mode signal ,Electrical and Electronic Engineering ,business ,Residual time ,Remote sensing - Abstract
We demonstrate the capability of the Standard Time and Frequency Signal (STFS) broadcast via INSAT to provide time synchronisation with the Indian Standard Time to a 1–2 μsec accuracy in a differential mode. The data used in this study comprise of (a) those recorded at the Giant Metrewave Radio Telescope (GMRT) site at Khodad, Pune and (b) those simultaneously recorded at NPL. GPS receivers have been used at Khodad and at NPL to provide the time reference for measurements of the residual errors of the received STFS time. The residual time error in the received STFS is primarily due to error in the predicted satellite position and is similar at both stations. The common mode error largely cancels in the differential STFS leading to the present high time transfer accuracy. more...
- Published
- 1996
- Full Text
- View/download PDF
42. Influence of common-mode input capacitances on op.-amp. frequency response
- Author
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Daniël Baert
- Subjects
Frequency response ,Engineering ,business.industry ,Hardware_PERFORMANCEANDRELIABILITY ,Hybrid-pi model ,law.invention ,law ,Hardware_INTEGRATEDCIRCUITS ,Electronic engineering ,Operational amplifier ,Common-mode signal ,Electrical and Electronic Engineering ,business ,Hardware_LOGICDESIGN ,Electronic circuit - Abstract
It is shown that the effect of op.-amp, common-mode input capacitances on the frequency response of a number of circuits cannot be neglected. It is possible to compensate for these effects at little cost. more...
- Published
- 1993
- Full Text
- View/download PDF
43. An autobalancer for seismic recording
- Author
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H. Holm and J. Eaglesham
- Subjects
Attenuator (electronics) ,Geophysics ,Electric power transmission ,Computer science ,Production model ,Full scale ,Electronic engineering ,Geology ,Common-mode signal ,Field conditions - Abstract
In an attempt to improve our services, GES has developed a common mode attenuator which we expect will greatly improve the quality of seismic data gathered near power transmission lines. A two channel prototype has been successfully tested in the laboratory as well as under actual field conditions. The first full scale production model is presently under construction. more...
- Published
- 1984
- Full Text
- View/download PDF
44. Signal flow-graph analysis of symmetrical circuits
- Author
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Václav Dvoěák
- Subjects
Amplifier ,Differential amplifier ,Common source ,Isolation amplifier ,Fully differential amplifier ,law.invention ,Computer Science::Emerging Technologies ,law ,Operational amplifier ,Electronic engineering ,Common-mode signal ,Electrical and Electronic Engineering ,Direct-coupled amplifier ,Mathematics - Abstract
Signal flow-graph technique has been applied to symmetrical circuits such as differential amplifiers. The differential amplifier is represented by common mode and differential mode subgraphs, which are, due to unavoidable asymmetries in the circuit, connected in either way. The basic parameters of the amplifier may be easily calculated if only one-way connection of two subgraphs is considered. The method is illustrated on a FET differential amplifier. more...
- Published
- 1974
- Full Text
- View/download PDF
45. Technology of double parallel pyroelectric detector
- Author
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B. B. Lavrenčkičk, A. Kandušker, P. Cevc, and J. Polanec
- Subjects
Optics ,Materials science ,business.industry ,Infrared ,Connection (vector bundle) ,Detector ,Electrode ,Common-mode signal ,Condensed Matter Physics ,business ,Electronic, Optical and Magnetic Materials ,Pyroelectricity - Abstract
Pyroelectric infrared detectors are efficient and cheap sensors for many applications. In order to acquire a common optic mode rejection capability, the double serial or parallel construction of active electrodes has been employed. The latter type is difficult to construct due to connection between the electrodes. The usual solution is to mount the two separate thin crystalline active elements on the separate holders. This technique lacks uniformity and precise cancellation of common mode. We have found the way to construct and fabricate the double parallel detector formed on a single piece of thin pyroelectric material. In this paper we describe the technology as well as the results of the detector parameter measurements. more...
- Published
- 1989
- Full Text
- View/download PDF
46. SEECOM-5: A Cost Effective Method of Reducing Common Mode Derived 50 Hz Signals
- Author
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P. Grimison
- Subjects
Physics ,Attenuation ,Acoustics ,Amplifier ,Geophone ,Geology ,Physics::Geophysics ,law.invention ,Twisted pair ,Geophysics ,Amplitude ,law ,Electromagnetic coil ,Common-mode signal ,Leakage (electronics) - Abstract
Any signal in the seismic spectrum which, at the input to the seismic amplifier, has an amplitude and/or phase difference between one leg of the twisted pair and the other, will be treated as a difference signal and amplified. All signals generated by coil movements in the geophones fall into this category. On the other hand, all common mode signals would ideally be attenuated severely since they have equal amplitudes and phases in each leg of the pair. (This is because of the high common mode attenuation performance of modern amplifiers.) In practice, however, this is not the case, as in many instances the seismic pairs are in substantial imbalance due to poorly manufactured or repaired cables, or due to high leakage currents to one another or to earth. more...
- Published
- 1984
- Full Text
- View/download PDF
47. Matrix Analysis of a Difference Amplifier Using Junction FETs
- Author
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S. Sridhar and K. Nagamuneswara Rao
- Subjects
FET amplifier ,business.industry ,Amplifier ,Differential amplifier ,Computer Science Applications ,Theoretical Computer Science ,law.invention ,Control theory ,law ,Operational amplifier ,Optoelectronics ,Common-mode signal ,Field-effect transistor ,Matrix analysis ,Electrical and Electronic Engineering ,business ,Mathematics ,Matrix method - Abstract
Analysis of an unsymmetrical difference amplifier with junction field effect transistors is carried out using matrix methods. Expressions for common mode, differential mode, common mode to differential mode and differential mode to common mode transmission coefficients are obtained. An expression for the common-mode rejection ratio of the difference amplifier is derived. more...
- Published
- 1976
- Full Text
- View/download PDF
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