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This article presents an electromagnetic compatibility (EMC) aware motor design method based on the prediction of the impedances of a stator winding structure. The stator structure is divided into several two-dimensional parts, and their network parameters are extracted by electromagnetic (EM) simulations. Through conversion and synthesis of the multiport network parameters, the input impedance can be found for the full-winding structure. The calculated input impedance approximately follows the measured impedance of tested induction motors. The impedance calculation method has been realized in a parametric analysis platform to enable the EMC-aware design of induction motors. By using the platform, the variations of the input impedances by different design parameters can be analyzed along with consideration of loss and torque ripple. To verify the proposed method, prototype motors were assembled and the common-mode (CM) currents were measured under driving operation. The results show that the CM current can be reduced up to 10 dB in the frequency range of interest when the number of parallel circuit is reduced, as estimated from the calculated input impedances. [ABSTRACT FROM AUTHOR]

Common mode (CM) filters play a crucial role in determining adherence to conducted emissions (CE) standards for grid-tied voltage source converters. Design and implementation of such filters can be challenging since they depend on several factors like identification of CM noise paths, fidelity of passive components and discerning the frequency and amplitude of CM noise sources. In this article, a CM filter has been proposed, which uses passive components along with the converter's heat sink as a circulating return path for the CM currents. Based on the presented CM circuit models with the proposed filter, a detailed design process has been delineated for selecting the passive components required to realize the CM filter. Additionally, the heat-sink potential has been shown to be touch safe during both ideal and nonideal grid conditions with the proposed CM filter. CE spectral results measured using a commercially procured line impedance stabilization network and captured time domain converter operational wave forms for a 2-level, 3 φ grid-tied voltage source converter validate the functionality and effectiveness of the presented design. [ABSTRACT FROM AUTHOR]

In this paper, we first proposed a novel hybrid loop array (HLA) for low leakage electromagnetic field (EMF) level and high efficiency in a wireless high power transfer system. The proposed HLA effectively enhances the system efficiency and shields leakage EMF in a wireless power transfer (WPT) system using kHz range resonant frequency. The key originality of the proposed HLA is the combination of two types of loop coil; shielding loop coil (SLC) and amplifying loop coil (ALC). SLCs reduce leakage EMF, and ALCs significantly enhance the magnetic field from a Tx coil. The simulation and experiment results show that the proposed solution successfully overcomes the limitations of the existing solutions. Analytical modeling and design procedure are introduced and discussed. In addition, the experimental verification of the simulation result is included. We first designed and modeled an HLA considering the coupling effect of neighboring loop coils to evaluate its efficiency and leakage EMF. With the proposed HLA, we demonstrated a 9.36% improvement in the efficiency and 3 dBm reduction in the leakage EMF near the WPT system. [ABSTRACT FROM AUTHOR]

The paper presents an innovative concept of applying a combination of well-known selective harmonic elimination (SHE) and selective harmonics mitigation (SHM) methods to shape a spectrum of catenary current harmonics, generated by a traction drive system equipped with a voltage source inverter. Application of this method allows for reducing distorting influence of a modern rolling stock supplied by a 3 kV dc catenary on the railway signaling, command, and control systems. The efficiency of the proposed method is independent of synchronization of a vehicle's inverters and of load balance of traction motors, which makes it more reliable than as it is proposed in the literature. Results of computer simulations were presented and compared with laboratory measurements. The obtained dc-link current spectrum using the proposed SHE/SHM method was compared with spectra received using synchronized and unsynchronized sinusoidal pulse-width modulations (SPWMs). Based on the conducted tests, it was shown that the proposed method of control, which was implemented in a laboratory drive system, is effective in reducing dc side current harmonics in a frequency range of 1300–3100 Hz, which is used by track circuits on railway lines, e.g., in Poland. The technique proposed by the authors allows taking into account any restrictions arising from the technical nature of low-frequency traction drives. [ABSTRACT FROM PUBLISHER]

In this paper, a method to characterize the high-frequency (HF) behavior of six pack insulated gate bipolar transistors (IGBTs) power module (PM) is presented. The method is based on experimental measurements at the external pins of the device and it allows one to extract internal inductive and capacitive parasitic coupling without the knowledge of structural and physical parameters of the PM. The HF model of a six pack IGBTs PM has been developed, in the frequency range of 150 kHz–30 MHz, and it has been implemented in MATLAB environment. The method has been experimentally validated by comparing the frequency behavior of the PM with the simulated response. Moreover, the HF conducted disturbances, generated by the PM and measured in the dc link, have been compared with the simulation results verifying the proposed model. [ABSTRACT FROM AUTHOR]

Reliable operation of the smart grid requires assurance of the electromagnetic compatibility of sensitive smart metering systems and power electronic converters, which introduce high-level electromagnetic interference. As it has been experimentally shown, currently available, normalized, and frequency domain tests are ineffective for the evaluation of data transmission error hazards. The mathematical time-domain model proposed in this paper enables assessment of the probability of errors occurring in a given transmission signal for known interference parameters. The validity of the model and its practical applicability have been experimentally verified. [ABSTRACT FROM PUBLISHER]

This paper is dealing with the characterization of the electromagnetic compatibility of the direct current (dc) motors. It acts as the complements of the works achieved recently for the modeling of dc motor impedances. The contact mechanisms between the brushes and the collector blades which cause the electromagnetic interferences (EMIs) are explained and modeled. Knowing the operating conditions of the current intensity, voltage, and speed, EMIs are measured and analyzed in radio frequencies from 100 kHz to 108 MHz. The behavioral model proposed is based on Norton's equivalent circuit where the motor is assumed as a current generator representing the EMI source, associated in parallel with its impedance model. Specific identification methods are used to quantify the EMI model parameters. It is shown that the model is in good correlation with the measurement. The model was applied for estimating the conducted EMI generated by a dc motor with its filters, and then, validations with different dc motors were performed. [ABSTRACT FROM PUBLISHER]

Presented in this paper are the results of research connected with common mode (CM) interference generated by ac/dc/dc power electronic interfaces, which will very probably be commonly used in the future vehicle-to-grid systems. The results obtained show that the conducted CM interference generated by these converters in a low-voltage grid can be coupled to a medium-voltage (MV) network and observed at distant points under overhead MV lines. The developed passive CM voltage compensator dedicated for ac/dc/dc interfaces is recommended as an effective method for conducted interference reduction, preventing both aggregation and flow of interference in distant circuits. [ABSTRACT FROM PUBLISHER]

High-frequency (HF) models of electrical motors and power converters are greatly important for electromagnetic compatibility characterization of electrical drives and for electromagnetic interference (EMI) filter design. In this paper, an accurate and effective method for the characterization and tuning of HF models (150 kHz–30 MHz) for induction motors has been proposed based on experimental measurements of the motor impedance. Impedance measurements have been taken in three different configurations: between all the six winding terminals which are shorted and grounded; between the three input terminals which are shorted and grounded (common mode); and between one input terminal and the other two which are shorted (differential mode). Once an HF motor model structure has been chosen and modeled using a state-space representation, its parameters have been tuned using genetic algorithm to match the real impedance in each corresponding configuration. Comparison between the experimental impedance measurements and the model impedance estimate are shown for all the tested configurations, in order to validate the model within the frequency range of interest for EMI. [ABSTRACT FROM PUBLISHER]

This paper provides a comprehensive guideline for the design of a single-phase PFC targeting for minimal volume, as it is highly relevant for ultracompact integrated systems. It is shown, how different operation modes (continuous, boundary, and discontinuous conduction mode) may influence the design and consequently the achieved power density. Furthermore, the effect of interleaving of several boost stages is analyzed as a measure for compactness increase. Finally, the selection of the appropriate switching frequency in order to achieve an overall optimized system is discussed. In this way, the design of the crucial components is carried out, namely, the boost inductor, including a volume optimization through a thermal connection to the heat sink; the output capacitor considering the rms current stress; and the input filter, which is designed for compliance with high-frequency electromagnetic compatibility standards, taking into account the quasi-peak detection measurement of the test receiver equipment. [ABSTRACT FROM AUTHOR]

The design of a single-phase boost power-factor- correction (PFC) circuit is associated with a large variety of considerations, such as the following questions. Which operation mode should be selected (e.g., continuous or discontinuous operation)? How many interleaved boost cells are advantageous? Which switching frequency should be selected? What is the optimum number of EMI input filter stages? Which semiconductor technology should be chosen? All these issues have a significant influence on the converter efficiency and power density. In this paper, the aforementioned questions are addressed for exemplary specifications of the PFC (300-W output power, 400-V output voltage, and 230-V mains voltage), whereby the focus in the design is mainly put on very high power density. As a result, different design points are identified and comparatively evaluated. By considering different aspects such as volume, losses, capacitor lifetime, and also cost issues (e.g., by additional current sensors or expensive silicon carbide devices), a dual-interleaved PFC operated in discontinuous conduction mode at 200 kHz is selected. With an experimental prototype, a superior power density of 5.5 kW/L and a system efficiency of 96.4% are achieved, which is close to the values predicted by the design procedure. Furthermore, measurements verify a near-unity power factor (PF = 99.7%) and the compliance with electromagnetic compatibility conducted noise emission standards. Finally, it is investigated to which extent the power density could be further increased by an integration of the input filter in the PCB. [ABSTRACT FROM AUTHOR]

Impulsive noise is known to be one of the most damaging types of wideband interference present in wireless communications systems, such as Universal Mobile Telecommunications Systems, Bluetooth, and Digital Video Broadcasting-Terrestrial. In order to quantify how impulsive noise degrades the quality of service (QoS) of a particular system and to evaluate the electromagnetic compatibility (EMC) requirements of a practical receiver under realistic impulsive noise conditions, it is necessary to use a flexible and modular impulsive noise generator. The primary objective of this paper is to present a low-complexity and highly flexible impulsive noise generator whose software module is implemented in a digital signal processor. In contrast to existing commercial equipment, the software implementation preserves the statistical characteristics of the measured impulsive noise parametars. In the proposed implementation, the generator presents two levels of flexibility that make it especially suitable for performing QoS tests and EMC conformance testing in realistic impulsive noise scenarios. First, the application is independent of the noise source under study. Second, the modularity of the testbed makes the generation of impulsive interference in different frequency bands possible. Experimental results confirm the feasibility and achievable performance of the proposed testbed. [ABSTRACT FROM AUTHOR]

Adjustable-speed drives involve common-mode voltages, which generate common-mode currents flowing to the ground through stray capacitances of electric machines. These currents are known to provoke premature motor-bearing failures, as well as electromagnelic interferences disturbing neighbor electronic devices. Furthermore, high-voltage applications involve high levels of these conducted emissions, which must be lowered by using bulky and expensive filters. This paper aims at elaborating a new pulsewidth-modulation (PWM) strategy in order to reduce the common-mode currents generated by three- level neutral-point-clamped inverters. The proposed strategy also provides the ability to balance the neutral point of the dc-bus capacitors. Experimental results both in time and frequency domains confirm that the new PWM improves the electromagnetic-compatibility behavior of the drive compared with conventional strategies. [ABSTRACT FROM AUTHOR]

For a three-phase buck-type pulsewidth modulation rectifier input stage of a high-power telecommunications power supply module, a differential-mode (DM) electromagnetic compatibility (EMC) filter is designed for compliance to CISPR 22 Class B in the frequency range of 150 kHz-30 MHz. The design is based on a harmonic analysis of the rectifier input current and a mathematical model of the measurement procedure including the line impedance stabilization network (LISN) and the test receiver. Guidelines for a successful filter design are given, and components for a 5-kW rectifier prototype are selected. Furthermore, formulas for the estimation of the quasi-peak detector output based on the LISN output voltage spectrum are provided. The damping of filter resonances is optimized for a given attenuation in order to facilitate a higher stability margin for system control. Furthermore, the dependence of the filter input and output impedances and the attenuation characteristic on the inner mains impedance are discussed. As experimentally verified by using a three-phase common-/Differential-Mode separator, this procedure allows accurate prediction of the converter DM conducted emission levels and therefore could be employed in the design process of the rectifier system to ensure compliance to relevant EMC standards. [ABSTRACT FROM AUTHOR]