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Electric vehicles (EV) offer promise as an effective solution to environmental problems. One of the keys to their successful diffusion is the provision of adequate battery charging infrastructure. In order to create a charging infrastructure by installing equipment in such as locations as carports in private homes, the wireless battery charging system is very suitable. EVs can be used in smart house systems to supplement the energy storage. This vehicle to home (V2H) system essentially requires a bidirectional power transfer feature between the EV and home. This paper presents a new bidirectional inductive power transfer (IPT) system for wireless V2H with simplest components and low cost aiming at wide diffusion for home use. Proposed is a novel type of bidirectional wireless EV charging system with an efficient and compact type single-ended quasi-resonant high-frequency inverter for V2H.

This paper is aimed at presenting a novel system topology and control scheme of a selective dual-mode pulse-modulated high-efficiency single-phase sinewave power-conversion circuit for the new energy generation and storage applications. This power-conversion system is composed of a time-sharing-operated sinewave-absolute-modulation boost chopper with a bypass diode in the first power conditioning and processing stage and time-sharing sinewave partially pulse-modulated full-bridge inverter in the second stage. The proposed power conditioner is operated by a selective time-sharing dual-mode pulse pattern signal processing control scheme without electrolytic capacitor dc link. The unique operating principle of the two-power conditioning and processing stages with sectional time-sharing dual-mode partial sinewave-modulation scheme is described and discussed with a design example. In addition, this paper proposes also a sinewave tracking voltage controlled soft switching pulsewidth-modulation boost chopper with a bypass-diode loop, which includes a passive auxiliary edge-resonant snubber. The new conceptual operating principle and the control implementation of this novel power conditioner are presented and evaluated through experimental and simulation results

Electric vehicles (EV) offer promise as an effective solution to environmental problems. One of the keys to their successful diffusion is the provision of adequate battery charging infrastructure. In order to create a charging infrastructure by installing equipment in such as locations as carports in private homes, the wireless battery charging system is very suitable. EVs can be used in smart house systems to supplement the energy storage. This vehicle to home (V2H) system essentially requires a bidirectional power transfer feature between the EV and home. This paper presents a new bidirectional inductive power transfer (IPT) system for wireless V2H with simplest components and low cost aiming at wide diffusion for home use. Proposed is a novel type of bidirectional wireless EV charging system with an efficient and compact type single-ended quasi-resonant high-frequency inverter for V2H.

A novel controller for generic servo systems using a neural network input-output measurement classifier and a staggered proportional plus integral plus derivative-like gain control scheme is proposed. The controller incorporates a knowledge-based control strategy and does not require a priori knowledge of the plant. The system controller is robust to both structured and unstructured uncertainties.

This paper presents an advanced method to improve the speed response characteristics of an AC servomotor drive system with mechanically resonant loads without any data-based experiences. Mechanical resonance and antiresonance are both effectively suppressed on the basis of a load speed feedback approach for the AC servo motion system. A novel /spl alpha/-parameter ultimate sensitivity method is applied to obtain a stable compensation between the proportional plus integral controller gains and load speed feedback gain. The fuzzy reasoning processing for this system is introduced for autotuning of the /spl alpha/ parameter. The effectiveness of the proposed autotuning control scheme in the AC speed servo system is verified in terms of computer simulation results.

The paper deals with an advanced control method of system gain parameter autotuning implementation for DC brushless servo drive system, which is based on a fuzzy reasoning logic with an automatically processed learning control strategy. In the learning operation, fuzzy rules are generated automatically so as to be suitable for unknown mechanical load which is linked to a servo motor shaft and memorised in a database. As a result, the performance in gain parameter autotuning scheme is improved in accordance with increasing the number of learning operations. The feasibility effectiveness of the practical application for this autotuning procedure in DC brushless servo drive systems is confirmed on the basis of experimental results.

A variety of ultrasonic motors (USMs) have attracted special interest as a new type of actuator in servo motion control systems. For practical applications, the speed servo control system incorporating the ultrasonic motor developed in Japan has some special unique features. However, this system has several significant problems, such as the inherent speed ripple characteristics, the speed regulation characteristics under the condition of applied disturbance load torque, and the speed tracking characteristics. In order to solve these practical problems, some control schemes of ultrasonic-actuated motor systems have been proposed and discussed theoretically, which include fuzzy reasoning control, adaptive control, repetitive learning control, and neural-network-based learning control. However, it is considered that these control strategies mentioned above have not been sufficiently substantiated from a feasible experimental point of view. This paper presents a newly proposed precise speed tracking servo control system using the compact traveling-wave-type ultrasonic motor. Its proposed control scheme is composed of both the driving frequency control loop with the variable-gain strategy and the applied voltage control loop with the speed ripple reduction strategy of the USM. The improved speed characteristics realized by this proposed control system are demonstrated and evaluated in experiments.

An LLC multi-resonant DC-DC converter with anti-resonant tank is presented in this paper. The five-element multi-resonant (LLC-LC) dc-dc converter can realize the wide range regulations of output voltage and power by pulse frequency modulation (PFM) under soft switching conditions. The resonant dc-dc converter proposed herein is suitable for renewable and sustainable energy applications such as battery chargers interfaced with a photovoltaic power generation system. In this paper, the design guideline of circuit parameters is originally described. Experiment results on the soft-switching performances and steady-state characteristics including the power loss analysis are demonstrated, thereby the effectiveness is verified from a practical point of view.

This paper deals with a cost effective IPT wireless EV battery charger for smart house, which incorporates the simplest quasi -resonant soft switching pulse modulated inverter using the latest SiC-MOSFET into high-frequency isolated DC-DC converter.

Electric Vehicles (EV) offer promise as an effective solution to environmental issues. One of the key technologies to their successful diffusion is the provision of adequate battery/capacitor charging infrastructure. In order to create a charging infrastructure by installing equipment in such as locations as carports in private homes, the inductive power transfer (IPT)-wireless battery charging system is very suitable. It is a promising system for wider diffusion because it is easy and safe to use for a broad range of users including the elderly. This paper presents a new system with the simplest components and low cost aiming at wide diffusion for home use. Proposed is a novel type of IPT-wireless EV charging system with an efficient and compact type single-ended load-resonant high-frequency inverter and DC-DC converter using SiCMOSFET. The single-ended high-frequency resonant inverter, which can operate under a self-excited ZVS control and a PFM power regulation scheme is evaluated from an experimental point of view. This system can supply a controlled charging current successfully with simple output stage. A feasibility study result is presented as a charging system for the commuter EV to demonstrate the viability of the proposed system.

In this paper, a novel grid integration system for a variable-speed wind turbine using Interior Permanent Magnet Synchronous Generator (IPMSG) is developed. The power-conditioner system(PCS) consists of a series-type 12-pulse diode rectifier powered by a phase shifting transformer and then cascaded to a PWM voltage source inverter. The series-type 12-pulse diode rectifier of the generator-side converter can work without any control, while the q-axis active current of the grid-side PWM inverter is only controlled to follow the optimized active current reference. The optimal active current reference is determined by using a simple MPPT algorithm which requires only three sensors in order to track the maximum power of the wind turbine. The losses in the IPMSG can be effectively reduced by setting a passive filter at the generator terminals. The laboratory results indicate that the proposed construction and scheme are simple, cheep and efficient.

SiC-SIT power semiconductor switching devices has an advantage that its switching time is high speed compared to those of other power semiconductor switching devices. We adopt newly developed SiC-SITs which have the maximum ratings 800V/4A and prepare a breadboard of a conventional single-ended push-pull(SEPP) high frequency inverter. This paper describes the characteristics of SiC-SIT on the basis of the experimental results of the breadboard. Its operational frequencies are varied at from 100 kHz to 250kHz with PWM control technique for output power regulation. Its load is induction fluid heating systems for super-heated-steam production.

This paper presents a high-efficiency one stage ZVS-PWM resonant single-ended push-pull (SEPP) high frequency inverter with new PFC functional scheme. This high-frequency resonant power converter with lossless snubbing capacitors which is composed of a passive PFC converter operating at one diode conducting full bridge circuit mode consists of asymmetrical ZVS-PWM high frequency inverter with non-bulky electrolytic capacitor stage for DC boosted voltage smoothing and induction heated load with tuned capacitor, and boost inductor between HFAC side and mid point of. The periodic steady-state operating principle of one stage high frequency series load resonant inverter with lossless capacitor is described by using the switching mode equivalent circuits in addition to the simulated operating voltage and current waveforms. The operating performances of this high-frequency ZVS-PWM resonant inverter with lossless snubbing capacitors are also illustrated on the basis of simulation analysis, which includes its UFAC-to-HFAC power regulation characteristics, soft switching operating range, UFAC side power factor characteristics and line current harmonics characteristics by FFT analysis. In principle, the effectiveness of this UFAC-to-HFAC direct power frequency converter designed for consumer high-frequency III appliances is evaluated and proved on the basis of simulation results.

This paper presents a single ended push-pull (SEPP) high frequency inverter incorporating a reverse blocking active auxiliary quasi-resonant circuit using bipolar mode static induction transistors (BSITs) as active switches. This inverter can realize soft switching of the active switches over wider output power regulation range compared with the conventional SEPP inverter. It is performed by incorporating an auxiliary active switch to the conventional SEPP inverter to feed a required current for the soft switching operation of the main switches. The current fed to the main switches during their short switching period assists their soft switching operation over wide output power regulation range. The detailed evaluation of its operational principle and characteristics is carried out with the aid of computer aided simulation and the experimental result obtained by a bread board.

This paper deals with a novel type soft switching utility frequency AC-high frequency AC converter using asymmetrical PWM bidirectional active switches which can be defined as high frequency resonant matrix converter. This power frequency changer can directly convert utility frequency AC power to high frequency AC power ranging more than 20 kHz up to 100 kHz. Only one active edge resonant capacitor-assisted soft switching high frequency load resonant cyclo-converter is based on asymmetrical duty cycle PWM strategy. This high frequency cyclo-converter uses bidirectional IGBTs composed of anti-parallel one-chip reverse blocking IGBTs. This high frequency cyclo-converter has some remarkable features as electrolytic capacitorless DC busline link, unity power factor correction and sinewave line current shaping, simple configuration with minimum circuit components and low cost, high efficiency and downsizing. This series load resonant cyclo- converter incorporating bidirectional active power switches is developed and implemented for high efficiency consumer induction heated food cooking appliances. Its operating principle is described by using equivalent circuits. Its operating performances as soft switching operating ranges and high frequency effective power regulation characteristics are discussed on the basis of simulation and experimental results.

This paper presents a utility frequency AC (UFAC) to high frequency AC (HFAC) direct power frequency conversion pulse modulated conditioning circuit using bidirectional power switches. This power converter can efficiently operate under a principle of active zero voltage clamped soft commutation for consumer induction heating (IH) fixing roller for copy machine and printer. This HFAC direct power frequency converter defined as resonant high frequency PWM controlled power frequency converter using bidirectional switches is developed and evaluated in this paper for consumer IH fixing heat roller using industrial HFAC power supply. Its operating principle is described on the basis of switching mode equivalent circuits during switching one cycle period. It is evaluated on the basis of its simulation and experimental results on the performances of HFAC direct power frequency converter treated here including various duty factor control variable vs. HFAC power regulation characteristics as well as zero voltage soft switching ranges.

This paper presents a utility frequency AC (UFAC) to high frequency AC (HFAC) direct power frequency conversion pulse modulated conditioning circuit using bidirectional power switches. This power converter can efficiently operate under a principle of active zero voltage clamped soft commutation for consumer induction heating (IH) fixing roller for copy machine and printer. This HFAC direct power frequency converter defined as resonant high frequency PWM controlled power frequency converter using bidirectional switches is developed and evaluated in this paper for consumer IH fixing heat roller using industrial HFAC power supply. Its operating principle is described on the basis of switching mode equivalent circuits during switching one cycle period. It is evaluated on the basis of its simulation and experimental results on the performances of HFAC direct power frequency converter treated here including various duty factor control variable vs. HFAC power regulation characteristics as well as zero voltage soft switching ranges.

This paper deals with a novel type soft switching utility frequency AC- high frequency AC converter using asymmetrical PWM bidirectional active switches which can be defined as high frequency resonant matrix converter. This power frequency changer can directly convert utility frequency AC power to high frequency AC power ranging more than 20 kHz up to 100 kHz. Only one active edge resonant capacitor-assisted soft switching high frequency load resonant cyclo-converter is based on asymmetrical duty cycle PWM strategy. This high frequency cyclo-converter uses bidirectional IGBTs composed of anti-parallel one-chip reverse blocking IGBTs. This high frequency cyclo-converter has some remarkable features as electrolytic capacitorless DC busline link, unity power factor correction and sinewave line current shaping, simple configuration with minimum circuit components and low cost, high efficiency and downsizing. This series load resonant cyclo-converter incorporating bidirectional active power switches is developed and implemented for high efficiency consumer induction heated food cooking appliances. Its operating principle is described by using equivalent circuits. Its operating performances as soft switching operating ranges and high frequency effective power regulation characteristics are discussed on the basis of simulation and experimental results.

This paper present an improved circuit topology for a buck chopper type single phase PFC-AC/DC converter with active power filtering function, which has smaller in reactor size and lighter in its weight, and can minimize the DC output voltage ripple factor. In addition, this active PFC-AC/DC converter can be also suppressed the current harmonics in utility AC grid without any specific feedback control scheme with current sensor interface. The circuit configuration treated here is more suitable for a variety of emergency power as well as telecommunication supply, where the lightning resistance is particularly considered to be more effective for 48 V-10 A output specification. In this paper, the operating principle of proposed AC-DC converter circuit using power MOSFETs and its related control implementation are described, along with its simulation and experimental results and their evaluations. The extended PFC-AC/DC converter topologies are demonstrated, which are operating at the proposed control scheme.

The oscillation voltage (Ebm) is an important parameter of the characteristic constant of a high power microwave generator. When Ebm could be made high, it serves so as to improve the power conversion efficiency of a magnetron. Thus, the newly developed magnetron with 7% higher oscillation cut-off voltage than the present conventional one is manufactured by Matsushita Electric Industrial Co.Ltd. In addition to this, the utility AC power line current reduced harmonic type direct inverter AC-DC power converter suitable and acceptable for driving this magnetron is proposed in this paper. This direct high frequency inverter type soft switching PWM AC-DC converter has the voltage-boost function based on active clamp scheme with soft switching pulse modulation strategy topology. This paper describes a novel type active clamp AC-DC power converter circuit defined as direct high frequency inverter and the switching operation of this power converter is described and discussed on the basis of simulation and experimental results. The operating characteristics of this soft switching direct high frequency inverter type AC-DC power converter using IGBTs that incorporates the harmonic current improvement as well as power factor correction are evaluated and discussed from a practical point of view as compared with the conventional AC-DC power converter.

This paper presents a novel phase shifted ZVS-PWM high frequency load resonant inverter for electromagnetic induction fluid heating (IH) appliances. The proposed high frequency inverter can be achieved stable and efficient zero voltage soft commutation over a widely specified power regulation range from full power to low power by using an active auxiliary quasi resonant snubber. The steady state operating performance of this inverter is evaluated and discussed on the basis of simulation and experimental results for IH dual-packs heater (DPH) of compact fluid heating appliance. Finally, the effectiveness of IH application of the proposed high frequency inverter with auxiliary active quasi-resonant snubber is demonstrated from the practical point of view.

This paper presents a novel dynamic model in the stationary reference frame for a diode bridge rectifier with a DC-link filter directly connected to a three-phase induction generator (IG). Moreover, a hybrid excitation system, consisting of a capacitor bank and an active power filter (APF), provides the pure sinusoidal currents needed to excite and control the stand-alone IG system's output voltages. A deadbeat current control strategy for the APF is used to enhance the operating performances of the stand-alone IG and reduce the size of the APF. This power generating system can be used for small hydro and wind rural applications where its generated electrical power is supplied to DC and AC loads. The measurement results validate the proposed power generating system with the deadbeat current controller as a good application for the IG to reduce the total system cost and the required number of sensors

B-SIT has an advantage that its on-resistance is extremely low compared to those of other power semiconductor switching devices. Accordingly, we can suppress its conduction losses during large current operation. Then, high conversion efficiency is expected when B-SITs are utilized as the switching devices of high frequency inverters. Here, we adopt newly developed B-SITs which have the maximum ratings 150 V/50 A and prepare a breadboard of a conventional single-ended push-pull (SEPP) high frequency inverter, which has a simplified circuit constitution and relatively wide range applications. This paper describes the characteristics of B-SIT on the basis of the experimental results of the breadboard. Its operational frequency is fixed at 50 kHz with PWM control technique for output power regulation. Its load is induction fluid heating systems for super-heated-steam production

This paper presents a novel boost-full bridge cascade system topology without electrolytic capacitor DC filter link and its time-sharing control scheme of a selective dual mode pulse modulated high efficiency single-phase sinewave power conversion conditioner for small scale new energy generation applications. This power conversion system is composed of a sinewave absolute value tracking boost chopper with a bypass diode in the first power stage and sinewave PWM full-bridge inverter in the second power stage operated by dual mode selective time-sharing pulse pattern signal processing control approach. The unique operating principle of two power conditioning and processing stages with sectional time-sharing dual mode partial sinewave modulation scheme is described and discussed for stand alone utilization. The paper proposes a sinewave tracking voltage controlled soft switching PWM boost chopper with a bypass diode loop, which includes a passive auxiliary edge-resonant snubber. The new conceptual operating principle of this novel sinewave pulse modulated power conditioner acceptable for small scale new energy generation is evaluated through the experimental and simulation results, together with a control implementation

This paper presents a novel prototype of active voltage-clamping capacitor-assisted edge resonant soft switching PWM inverter operating at a constant frequency variable power (VPCF) regulation scheme, which is suitable for consumer high-power induction-heating cooking appliances. New generation IGBT with a trench gate is particularly improved in order to reduce conduction loss due to its lowered saturation voltage characteristics. The soft switching load resonant and quasiresonant inverter designed using the latest IGBTs is evaluated from an experimental point of view.

This paper presents a novel quasi-resonant ZVS-PWM DC-DC converter using Phase-Shifted Modulation (PSM) in secondary AC side of highfrequency transformer. A newiy-proposed DC-DC converter with high-frequency link can minimize the freewheeling current through the transformer primary and secondary side circuits. Thus, the conduction losses of this soft-switching DC-DC converter can be substantially reduced as compared with those of traditional hard-switching PWM DC-DC converters. Furthermore, the proposed DC-DC converter can achieve zero voltage soft-switching PWM operation with low commutating current as well as zero current soft-switching rectifier operation in steady-state which is independent with load current. The principle of this operation and performances in analysis are illustrated and discussed by means of computer-aided simulating results and experimental ones.

This paper presents a two-switch boost-half bridge one stage power conversion circuit topology of commercial single-phase utility frequency AC fed ZVS-PWM power converter with harmonic current suppression and unity power factor correction functions. This cost effective utility frequency AC (UFAC) to high frequency AC (HFAC) power converter is developed for consumer induction heating (IH) appliances. This two-switch boost-half bridge one stage UFAC to HFAC power converter includes some advantages as simple configuration and control scheme, low cost, utility AC side harmonic current reduction with unity power factor, and constant frequency ZVS-PWM for power regulation. Its operating principle is described and discussed herein. In addition to this, its operating performances are illustrated and estimated on the basis of simulation and experimental results. An active voltage clamped ZVS-PWM high frequency inverter with boost function and its characteristics are also evaluated as compared with two-switch boost-half bridge power converter treated here

In this paper, a novel topology of soft switching PWM high frequency AC power conversion conditioning and processing circuit without DC smoothing capacitor filter link from the voltage grid of utility frequency AC power supply source with 60 Hz-100 V or 60 Hz-200 V is proposed and introduced for innovative consumer induction heating (IH) boiler applications as a hot water producer, steamer and super heated steamer. The operating principle of utility frequency AC-high frequency AC power frequency conversion circuit defined as high frequency cycloinverter is described, which can efficiently operate under a principle of zero voltage soft switching and regulate by means of positive and negative alternate asymmetrical PWM synchronized with the utility frequency single phase AC voltage. The dual mode control scheme based on high frequency PWM and commercial frequency AC voltage PDM for high frequency cycloinverter are discussed in order to extend its soft switching commutation operating range in spite of power regulation. This power frequency changer as high frequency cycloinverter is developed originally for the high frequency induction heating boiler in consumer and industrial fluid pipeline system. It is verified on the basis of experiment and simulation results in the steady state operation of the high frequency cycloinverter using IGBTs which is suitable for the business-use IH boiler using new electromagnetic induction heating dual packs fluid heater. Finally, the power regulation characteristics in addition to utility AC side line current harmonic components and power factor characteristics and power conversion efficiency characteristics of this high frequency cycloinverter are evaluated and discussed from an experimental point of view.

This paper presents a single phase utility AC connected two-switch boost-half bridge one stage high frequency power conversion circuit topology with boosted DC link and active power filter function, which is more suitable for consumer IH appliances as cooking heater and super heated steamer. The proposed high frequency power converter is composed of power conversion conditioning and processing combined by discontinuous current mode boost type power factor correction converter and half bridge ZVS-PWM high frequency single ended push pull load resonant inverter. This power converter include some advantages such as simple configuration and control scheme, low cost, utility AC side harmonic current PWM for power regulation. Its operating principle is described and discussed herein. In addition to these, the operating performances of the proposed power converter using IGBTs are illustrated and estimated on the basis of simulation and experimental results. Its practical effectiveness as consumer induction heater mentioned above is actually proved from an experimental point of view. Moreover, to extend soft switching operation ranges of this power converter for low power setting, switching frequency selection approach based on switching frequency selected asymmetrical PWM is discussed in this paper

In this paper, the buck-boost converter circuit, which we have named "neutral-point type", based on the new approach is proposed. Operations and characteristics of this circuit are reported. And, it is shown that this converter can be applied to the electronic ballast for the lighting. This circuit is effective for reduction of harmonic current. When it was applied to the electronic ballast, it also has the advantage that reduces the following characteristics of the circuit: 1. withstand voltage of circuit element, 2. inrush current and 3. ripple of output voltage. The experimental result of electronic ballast is also reported.

In this paper, the circuit of high frequency power supply for the electrodeless discharge lamp is proposed. In order to obtain the high power, the circuit is made by combining outputs of parallel four 125 W power conversion circuits. This method is effective in order to make the high power circuit with the low cost in small space. The design of 500 W-class high frequency power supply for electrodeless discharge lamp with 2.6 MHz is reported. The electric power transmission from the power supply to the load carried out using coaxial cable. The control circuit for operating the lighting equipment in the high reliability is also reported.

This paper presents a new conceptual electromagnetic induction eddy current-based stainless steel spiral type heater for heat exchanger in hot water producer and boiler, which is suitable and acceptable for new generation consumer power application. In addition, an edge-resonant PWM high frequency inverter using IGBTs can operate under a principle of zero voltage soft commutation is developed and demonstrated for a high efficient induction heated hot water producer and boiler in the consumer power applications. This consumer power appliance using soft switching PWM high frequency inverter is discussed and evaluated on the basis of simulation and experimental results.

The oscillation voltage (Ebm) is an important parameter of the characteristic constants of a magnetron. When Ebm is made high, it serves so as to be able to improve the efficiency of a magnetron. Thus, the magnetron with 7% higher oscillation voltage than the former one is developed by Matsushita Electric Industrial Co.Ltd, In addition to this, the reduced harmonic type AC-DC converter suitable for driving this magnetron is proposed lately. This inverter type converter has the voltage-boost function of an active clamp scheme with soft switching pulse modulation strategy topology. This paper describes a novel type of active clamp AC-DC converter circuit and the operation of this converter which was developed. The operating characteristics of this soft switching converter are evaluated from a practical point of view as compared with the conventional converter.

This paper presents a high efficiency and high performance continuous fluid-heating appliance in the pipeline system using soft switching high frequency inverter which is base on the electromagnetic induction heating processing. Its operating performance as a hot water producer is evaluated and discussed on the basis of experimental and simulation results.

This paper presents a digital control scheme for a four-quadrant high frequency PWM chopper type power conversion amplifier. It is the gradient magnetic field current pattern generator which is designed for medical use MRI. The main research objective of this paper is to propose the current control implementation in gradient magnetic coil (GC), which is driven by a high frequency PWM DC-DC converter system with a four-quadrant output scheme. The current pattern required for GC should follow up in accordance with any desired current pattern. In this current amplifier system, the current servo controller employs the optimum type-1 predictive control strategy, which has the advantages for the multiple input voltage and output current. The dynamic and steady state performances of the current PWM amplifier are described and evaluated on the basis of simulation analysis.

This paper presents a novel version of an active voltage clamped ZVS-PWM high frequency inverter using IGBTs for electromagnetic induction eddy current-based rolling drum heating in new generation copy and printing machines in consumer business use. The operating principle of this inverter circuit and unique features are described herein. Its constant frequency duty cycle (asymmetrical PWM) controlled voltage source quasi-resonant soft switching high frequency inverter employing IGBTs is proposed, which is capable of achieving stable and efficient zero voltage soft switching commutation over a widely specified power regulation range from full power to low power. The operating performances in a steady state of this inverter is discussed and evaluated on basis of simulation and experimental results as an induction heated roller in new generation copy machine.

In this paper, two types of load speed observers especially designed for load speed feedback compensation AC servo system with mechanically resonant load are proposed. The effectiveness of the observers are verified on the basis of both computer simulation and experiment.

This paper presents a four-paralleled full-bridge-type PWM current controlled power amplifier using IGBTs in order to generate high speed gradient magnetic fields for magnetic resonance imaging system (MRI) and its unique parallel processing digital control scheme based on a phase-lead compensator by a reference delay and a load model feedforward in addition to a dead time compensator. The maximum output voltage of the current controlled power amplifier is 600 VDC and its maximum current is 400 A for inductive loads. The observed waveforms in its experiment are illustrated to demonstrate the effectiveness of the four-paralleled full-bridge power amplifier topology and its unique control scheme.

Most neural network (NN) based trajectory tracking controllers for servo systems are built on learning explicit inverse dynamics of the system to be controlled. However, due to various complexities in these systems, the learning process may require a large amount of training data to obtain the exact dynamics of the system. To overcome this problem a novel NN based trajectory tracking controller is introduced which neither requires a priori knowledge of the dynamics nor learning of system dynamics. The proposed control scheme incorporates expert knowledge and is decentralized to deactivate the coupled dynamics associated with certain systems like robotic manipulators. The NN is employed to classify the system input-output measurements into several patterns depending on the displacement and velocity deviations from the respective desired trajectories. A proportional plus derivative gain control action is determined from a look-up table corresponding to the classification from the NN. Furthermore, an integrator is applied to enhance system performance. Several PD gains are introduced in a staggered format relative to the magnitudes of the displacement and velocity tracking errors, resulting in a controller that is robust to both structured and unstructured uncertainties.

In this paper, in order to suppress the mechanical resonance and anti-resonance in a DC brushless motor-based AC speed servo system with two-mass mechanical motion load, a load speed observer with a load disturbance estimating function which is suitable for the load speed feedback compensation is proposed. Then, the gain parameters auto-tuning control implementation which is based on fuzzy reasoning with the observer-based load speed feedback compensation in addition to the conventional PI compensation is proposed and discussed from experimental point of view.

In this paper, a circuit topology of an active voltage clamped quasi-resonant PWM inverter-type DC-DC converter using IGBTs is proposed in order to improve the function of conventional single-ended soft switching converter for a magnetron drive. This converter includes some advantages capable of clamping the peak voltage across the main power semiconductor switching device. In addition, the anode current was reduced by up to 1.2 A with a magnetron as a load of this converter. Furthermore, the special modulation pattern for the operating frequency and PWM of the inverter is also proposed in order to improve line current distortion and power factor in utility AC power side. Harmonic current components in utility grid AC power side are regulated under the condition of the peak value limitation of the anode current of magnetron and soft switching PWM strategy.

A high-frequency-link AC-to-DC converter with sinusoidal input current and high-quality power factor is discussed. A bridge configuration is used for both boosting and inverting stages. Input line current is sensed and firing of the power transistors S/sub 1/ to S/sub 4/ is inhibited using a pulse-width modulation (PWM) modulator. The proposed AC-to-DC converter, which includes control circuitry for instantaneous current control implementation, is capable of providing a wide-range-regulated output direct voltage. A performance evaluation of the proposed converter was carried out theoretically and experimentally, with highly satisfactory results. >

The authors describe a novel conceptual multistage topology of a sinewave-modulated DC-LFAC (DC-low-frequency AC) power conversion conditioning and processing system, which incorporate a phase-shifting PWM (pulsewidth modulation) series-resonant cycloinverter (inverter-coupled cycloconverter cascade circuit) with a high-frequency AC (HFAC) transformer link. Its advanced hardware of system control implementation uses instantaneous sinewave-modulated voltage regulation and compensation strategies, depending upon load disturbance and input DC voltage fluctuation, as well as an instantaneous power regenerating regulation scheme. A newly proposed breadboard using MOS-gate power transistor modules is demonstrated and experimentally tested for high-power-density AC mini-uninterruptible power supply. This series resonant cycloinconverter with HFAC link, which includes the control function of a bidirectional power flow, is evaluated as an AC power supply system for telecommunication and spacestation/aerospace energy situations in the next generation. >

The authors describe a state-of-the-art pulse density modulation (PDM) AC/DC power converter with an active clamped resonant DC link (ACRDCL) and a DSP-based system control strategy which relates unity power factor correction and sinewave line current shaping. The operating principle of the soft-switched AC/DC power converter and the clamping-voltage distributed PDM (modified-PDM) strategy and its performances are illustrated and discussed using simulation results. Experimental results are evaluated. >

A generic family of high power density DC-DC power converter topologies with high-frequency AC link and without transformer isolation link is described. A saturable reactor assisted (SRA) soft switching mode constant frequency pulse width modulation (PWM) technique efficiently operates at a zero voltage switching transition scheme. This kind of quasi-trapezoidal wave mode PWM DC-DC power converter incorporates a small saturable reactor or a few saturable reactors in order to achieve efficient soft switching commutated operation. The use of the converter family results in much higher switching operation with a high efficiency and a quick control response. A simple forward/flyback hybrid type SRA asymmetrical PWM soft switching DC-DC power converter with high frequency link, which is included in one of the SRA soft switched PWM converter topologies, is demonstrated and theoretically analyzed in steady-state operation. Key experimental results are shown and discussed using a 150 W, 200 kHz MOSFET power converter breadboard implementation. >

A zero voltage switched resonant converter has been designed and built as a transcutaneous energy transmission system to transfer 30 W across a variable air gap of 5-20 mm. The converter could power a total implantable artificial heart through intact skin by utilizing a transformer. In the converter, the large leakage inductances of the transcutaneous transformer have been incorporated in the resonant inductor. The steady-state operation of an experimental transcutaneous power supply has been accurately predicted by the theoretical analysis. >

The authors discuss a resonant capacitor voltage-clamped type half-bridge topology for an instantaneous resonant current vector-regulated high-frequency inverter with phase shifting control, which efficiently operates with zero current soft switched quasi-resonant and load resonant tank circuit subresonant hybrid soft switching schemes. This inverter uses static induction (SI) devices (SI transistors and thyristors) and is more suitable for modern induction heating and melting power supplies industrial production plants. Analytical results and performance evaluations are presented. A breadboard of a trial inverter is demonstrated for the state-of-the-art induction heating power supply and is examined experimentally. >

This paper is concerned with a newly improved version of the pulse density modulation (PDM) three-phase AC-DC converter including an active clamped resonant DC link (ACRDCL) and its digital signal processor (DSP) control strategy to achieve a unity power factor correction and sinewave line current shaping. The operating principle of the zero-voltage soft-switched three-phase AC-DC converter using ACRDCL under the control scheme of an instantaneous space voltage vector-based clamping-voltage distributed PDM (modified-PDM) scheme to improve its control response and operating performances is illustrated. Performance evaluations are discussed using simulation and experimental results, and a comparison with the conventional PDM converter is given. The experimental results of this active converter are shown from a practical point of view. Finally, the utility-interfaced ACRDCL double-converter system operating under the DSP controlled modified-PDM strategy is illustrated and evaluated by using simulation results under inductive load conditions. >