Power Semiconductor Converter Research Articles

СИНХРОННИЙ ВИПРЯМЛЯЧ В ІМПУЛЬСНОМУ СТАБІЛІЗАТОРІ ПОСТІЙНОЇ НАПРУГИ НА ОСНОВІ ВИСОКОЧАСТОТНИХ МАГНІТНИХ ПІДСИЛЮВАЧІВ

Requirements for semiconductor power converters with a high level of load current have been formulated. A review of research works addressing the problem of achieving maximum efficiency in DC voltage regulators using synchronous rectifiers based on modern field-effect transistors has been conducted. The proposed methods of synchronous rectification in pulse DC voltage stabilizers utilizing high-frequency magnetic amplifiers are described. These methods rely on the use of existing signals within the converter and eliminate the need for additional components or specialized drivers in their circuitry. The principle of operation is explained, and theoretical oscillograms are provided, which are validated by experimental data. Experimental results on the efficiency of such converters are presented. Specifically, the proposed methods of synchronous rectification in a pulse DC voltage stabilizer based on high-frequency magnetic amplifiers, with an output power of 300–400 W and input DC voltage of 310 V (equivalent to an industrial-frequency network), achieved an efficiency of 95%. References 21, figures 9.

MODEL OF THREE-PHASE ASYNCHRONOUS MOTOR WITH SHORT CIRCUIT ROTOR IN MATLAB PACKAGE

The presented paper examines the specifics of researching the mathematical apparatus of the model of a three-phase АМ with a short-circuited rotor in the matlab package. It has been proven that three-phase АМ with a short-circuited rotor form the basis of a modern electric drive in many branches of industry, agro-industrial complex and transport. A model was developed in the matlab package, which describes the operation of a frequency-regulated electric drive, taking into account theoretical analysis and experimental studies. In the scientific work, the task of combining mathematical modeling and modern computer technologies, which are based on application packages, is fulfilled, which gives the researcher the opportunity to deeply study the processes that occur in all links of the electric drive. With the help of the proposed model, quantitative and qualitative analysis of electromagnetic and electromechanical processes in transient and established modes of operation, research of dynamic mechanical and operational characteristics, analysis of spectral composition and hodographs of spatial vectors of phase voltage and current of an АМ can be carried out. The considered model can be applied not only when powering an asynchronous motor from a three-phase source with a sinusoidal form of voltage, but also when powering it from power semiconductor converters. The scheme of a virtual installation for modeling and researching processes in a three-phase АМ with a short-circuited rotor was developed in the work. The analyzed installation includes the following blocks: three-phase AC voltage source, three-phase AC voltage meter, Selector block, Voltage Measurement block, three-phase АМ under investigation, static torque assignment block, active and reactive power meter, Subsystem block. An analysis of electromagnetic processes in static and electromechanical converters of electrical energy was carried out using the spatial vector method, which has found wide use. With the help of software packages, instantaneous values of symmetrical three-phase variables such as voltage, current, flux linkage were mathematically transformed into one vector.

Analysis and improvement of power quality in the onboard electrical power systems within a self-propelled floating crane

This research addresses electromagnetic compatibility and power quality (EMC and PQ) challenges in shipboard electric power systems (SEPS) with dynamic positioning (DP) capabilities, focusing on the self-propelled floating crane (SPFC) “EXPERT 3.” Our goal is to enhance methodologies for evaluating power quality indicators (PQI) related to voltage and current waveform distortions, specifically in converter-based propulsion complexes (CBPCs) featuring variable-frequency regulated asynchronous drives (VFDs). We investigate harmonic current and voltage distortions, reactive power generation, and power factor (PF) in SEPS “EXPERT 3″ during the operation of VFDs with conventional semiconductor power converters (SPCs). A refined MATLAB model considers equipment and cable network parameters, validating distortion indicators at ship synchronous generators (SGs). PQI compliance with international maritime standards is verified at the point of common coupling (PCC) for various VFD configurations with pulse width modulated (PWM) SPCs and filter-compensating devices (FCDs). We propose an improved controlled FCD (CFCD) incorporating a resonance filter (RF) and a controllable reactor compensator (CRC). CFCD efficiency in various VFD configurations is experimentally validated. We analyze harmonic distortions of voltage and current, including high-frequency (HF) commutations in VFDs with input thyristor-based rectifiers (TBRs), considering parasitic ”phase-hull“ capacitances of cable line segments (CLS). Our study examines harmonics in CBPC-based SEPS in two sub-frequency ranges: low-frequency (LF) − 0 to 2 kHz and high-frequency (HF) − 2 kHz to 500 kHz.© 2017 Elsevier Inc. All rights reserved.

Design Proposals for High-Voltage Stacked Configuration GaN Module

In this paper, the operational verification of the stacked transistor configuration is provided, focusing on the use of GaN transistors. The methodology is based on simulated and laboratory experiments. The stacked transistor configuration appears to be a promising solution to increase the voltage-blocking capability of GaN technology for high-voltage operations. Currently available GaN transistors are manufactured for 650 V of blocking voltage. Devices with a higher voltage-blocking capability are not currently available. Therefore, the stacked module was verified, while the main focus was on the driving circuit design, verification, and testing. For this purpose, two alternatives of GaN transistor technology have been compared. The main goal was to reach 800 V of blocking voltage with acceptable voltage deviation for nominal power of a power semiconductor converter.

ANALYSIS OF THE MAGAMP POWER CONVERTER STABILITY TAKING INTO ACCOUNT OF THE INTERVAL UNCERTAINTY OF THE MAGAMP CORES PARAMETERS

To ensure the functioning of radio electronic equipment (RAE), semiconductor power converters (NPEs) are used, which perform the functions of converting and adjusting the parameters of electrical energy. The modern consumer needs NPEs with a rigid set of operational characteristics - ensuring functional parameters in a wide range of changes in all disturbing factors. The existing principles of NPE construction do not always allow such a set of characteristics to be realized. The article analyzes the stability of the pulse voltage stabilizer based on high-frequency magnetic amplifiers, taking into account the technological spread of their core parameters. The circuit of the voltage stabilizer is presented, its operation is described, the principle of operation of the high-frequency magnetic amplifier is disclosed, and its transfer function in the frequency domain is found. The study is based on the use of interval analysis theory. The conducted analysis of the stability of the NPE, taking into account the interval uncertainty of the parameters of the cores of high-frequency magnetic amplifiers, confirmed their performance both with technological dispersion of the parameters of the cores and with a wide range of changes in all disturbing factors, including the parallel operation of voltage stabilizers on a common load.

Activity of Technical Committee on Semiconductor Power Converter

Activity of Technical Committee on Semiconductor Power Converter

Повышение эффективности электропривода электровоза с управляемым преобразователем возбуждения тяговых двигателей

Purpose: To substantiate the circuit design and algorithms for individual smooth and automatic control of single-phase direct current electric locomotives according to the laws of constant traction force and constant power without breaking the electric locomotive power circuits in order to increase the efficiency of its electric drive with controllable traction motor excitation converters. As a circuit design solution, it is proposed to apply a power electrical circuit with two rectifier-inverter converters for each section of the electric locomotive for bogie-based traction control, as well as individually controlled bridge transistor converters, shunting field windings, for axial traction control within each bogie. Methods: The development of circuit solutions using modern power semiconductor converters; theory of automatic control and design of finite state machines; mathematical modeling of electromagnetic, electromechanical and mechanical processes. Results: The developed control algorithms provide the possibility of obtaining traction characteristics of an electric locomotive that vary according to the laws of constancy of traction force or constancy of power, bringing the traction characteristics of electric locomotives with collector traction motors to the characteristics of electric locomotives with asynchronous traction motors. The calculations performed confirmed the possibility of implementing an algorithm for individual control of traction motor currents and their excitation currents, as well as traction forces, which ensures a smooth increase in the traction force of an electric locomotive.Practical significance: The developed technical solutions applicable in the manufacture of modern and modernization of operated electric locomotives will ensure an increase in the traction properties of singlephase DC electric locomotives and will contribute to an increase in the throughput and carrying capacity of the railway network.

Evaluation of Electric Power Quality in the Ship-Integrated Electrical Power System with a Main DC Bus and Power Semiconductor Electric Drives as Part of the Electric Propulsion Complex

The relevance of the work is connected to the energy efficiency of specialized vessels of the technical fleet. The purpose of the study was to determine and evaluate the power quality indicators associated with the non-sinusoidal shape of the voltage and current curves in the electrical power system of the marine platform support vessel, which contains powerful semiconductor propulsion electric drives, taking into account the inherent and parasitic parameters of the power three-phase cable lines. A simplified one-line diagram of an electric power system with a DC main bus was the object of the study, which was compiled as a result of the analysis of analog systems typical for the indicated type of vessels. The phenomenon of voltage and current distortion caused by the presence of higher harmonics generated by power semiconductor converters in a three-phase ship network was the subject of the research. For the experimental study of the quality of electric power according to the simplified one-line scheme of the electric power system in MATLAB Simulink, its model was created. Based on the proven methods of calculating the ship’s electrical equipment, a methodology was developed for the reliable determination of model parameters. According to the results of the experiment in MATLAB Simulink, qualitative and quantitative indicators were obtained regarding the non-sinusoidality of the linear voltage and current of the three-phase network (curve shapes, amplitude spectra, distortion coefficients), and their comparative analysis with the current norms and standards was performed. In contrast to the previous ones, the methodology for assessing the quality of electricity in the studied electric power system takes into account its circuit, mode features, and the presence of a parasitic capacitance “phase to ground” of a three-phase network, and it can be used in solving similar non-trivial tasks for various similar structurally modified systems.

The Analysis, Modeling, and Control of the Forward DC/DC Converter for the Electric Vehicle

This article deals with the analysis, modeling, and control of the DC/DC converters. Although it is considered with the analysis of the power semiconductor converters in general however it can be applied also to sophisticated electronic devices perfectly suitable for on-board applications of a huge variety of transport vehicles. Specifically, as an example, the Forward type topology is used which offers the advantage of the galvanic isolation of output. The task is to obtain a state space description of the system, the transfer function of the control, and design controller parameters using MATLAB. The state space model and the transfer function is implemented for the ideal and nonideal type of topology, where it is considered with at least some parasitic parameters of circuit elements to get closer to real results of the physical sample and to compare obtained transfer functions based on their frequency characteristics.

Automatic Control System for a Power Semiconductor Converter in Diesel Locomotives with Collector Traction Motors

Automatic Control System for a Power Semiconductor Converter in Diesel Locomotives with Collector Traction Motors

Investigation of the Properties of a Five-Phase Induction Motor in the Introduction of New Fault-Tolerant Control

Multiphase electric motors in cooperation with power semiconductor converters belong to the future of electric drives. This is because of their better properties compared to three-phase motors, such as better fault tolerance. How a multiphase motor will behave in a fault state is very important when using such motors in EV and HEV. This is the basis of the research in this article; we investigate the options for operating a five-phase motor in a fault condition in order to improve the drive qualities during fault operation. The complete mathematical expressions of the five-phase induction motor model in the normal operation as well as in fault operation and also the control modification to improve the properties of the drive are presented. The new five-phase field-oriented control is next described, which improves the drive qualities in four-phase operation and is the first fundamental aspect of the study. Another important aspect of the project is the development of a specific control on a real motor, followed by measurements of properties of a five-phase motor in normal and fault operation of one phase without and with control modification to enhance drive characteristics. The qualities and appropriateness of employing a five-phase motor as a drive in EV and HEV are then determined by comparing these results. Finally, a comparison of motor attributes is shown with and without control adjustment.

Automatic control system of a power semi-conductor converter for diesel locomotives with collector traction motors EVSEEV V.Yu., SAVOS’KIN A.N

Automatic control system of a power semi-conductor converter for diesel locomotives with collector traction motors EVSEEV V.Yu., SAVOS’KIN A.N

Analysis of exact and approximating dependences of active resistance of a conductor on the current frequency based on the influence of skin effect

The operation of semiconductor power converters, which are part of tractionsubstations, frequency-controlled electric drives and other powerful nonlinear loads, cause asignificant emission of higher harmonics of currents to electrical networks. Higher harmonics ofcurrents in electrical networks cause a complex negative effect on the energy efficiency of thenetwork. The increase in power losses in the active resistance under the action of higher harmonicsis due to the increase in the root mean square value of the current and the action of the skin effect.Analytical expressions describing the dependence of the active and impedance of the electricnetwork on the current frequency are determined. Based on them, analytical expressions are obtainedfor the calculation of additional power losses under the action of higher harmonics of currents, whichare due to the skin effect. The dependences of the active resistance of the electric network on thefrequency of higher harmonics are determined on the basis of Bessel equations. The analysis of convergence of the received equations with the data of the international standard IEC 60287-1-1 iscarried out. For the high-frequency zone, simplified approximating dependences are given, whichdetermine the parabolic dependence of the active resistance on the frequency. Simplifiedapproximating dependences of active resistance on the frequency of higher harmonics are obtainedfor engineering calculations. The obtained equations can be used to determine additional powerlosses in the active supports of electrical networks, windings of electric machines, high-frequencytransformers from higher harmonics of currents at different nonlinear loads. In addition, the obtainedexpressions can be used to justify the use of filter-compensating devices.

Energy efficiency of power electronics converters in traction power supply networks at voltage increase

The main features of the procedure for predicting electrical losses in power semiconductor converters of AC-DC and DC-AC systems of high voltage DC traction are presented. The procedure is based on simulation of multi-cycle switching of IGBT modules in combination with simulation of static and dynamic switching losses in traction converter circuits. The models take into account the switching frequency, physical processes in the formation of voltage and current diagrams at transition processes and in the static state of the switch elements. The model of loss assessment using particular types of IGBT modules is the basis for calculating the energy efficiency characteristics of traction converters for advanced high-voltage direct current traction systems.

Current Status and Future Prospects of Marine Semiconductor Power Converters

Current Status and Future Prospects of Marine Semiconductor Power Converters

System Level Simulation of Microgrid Power Electronic Systems

In this paper, we describe a procedure for designing an accurate simulation model using a price-wised linear approach referred to as the power semiconductor converters of a DC microgrid concept. Initially, the selection of topologies of individual power stage blocs are identified. Due to the requirements for verifying the accuracy of the simulation model, physical samples of power converters are realized with a power ratio of 1:10. The focus was on optimization of operational parameters such as real-time behavior (variable waveforms within a time domain), efficiency, and the voltage/current ripples. The approach was compared to real-time operation and efficiency performance was evaluated showing the accuracy and suitability of the presented approach. The results show the potential for developing complex smart grid simulation models, with a high level of accuracy, and thus the possibility to investigate various operational scenarios and the impact of power converter characteristics on the performance of a smart gird. Two possible operational scenarios of the proposed smart grid concept are evaluated and demonstrate that an accurate hardware-in-the-loop (HIL) system can be designed.

ПРОЕКТУВАННЯ СИЛОВИХ ТРАНЗИСТОРНИХ ПЕРЕТВОРЮВАЧІВ ЕНЕРГІЇ ДЛЯ СИСТЕМ АВТОМАТИЗОВАНОГО ЕЛЕКТРОПРИВОДУ ПОСТІЙНОГО СТРУМУ

Purpose. One of the integral parts of modern mechatronic motion modules, where electric motors provide the conversion of electrical energy into useful mechanical action, are power semiconductor converters. At the current stage of industrial development, the use of energy converters as a part of a fully controlled semiconductor switches opens wide opportunities for the development and implementation of highly efficient resource- and energy-saving devices. Methodology. Two types of converters are widely used in automated DC electric drive systems: controlled thyristor rectifiers and pulse-width DC converters, the principle of operation of which is based on the key mode of operation of the regulating semiconductor, which periodically connects the source voltage to the output circuit. The paper presents a laboratory sample of a power semiconductor DC energy converter, which can ensure reliable motor operation in both motor and braking modes. Results. The presented transistor energy converter consists of two main parts: the first part performs the main role – control, and it includes a control unit, a microcontroller, and a device for displaying current information. The second part is a power module, which includes the necessary power supply modules, control drivers and power transistor switches of the converter. To obtain high quality transients of the electric drive system, the circuit is equipped with additional sensors of current, voltage and speed, which takes part in the formation of the control signal and in the protection systems against overvoltage and current jumps. Practical value. The paper substantiates the parameters of the components and proposes developed technical solutions for the construction of a microprocessor control system for a transistor DC energy converter. It is shown that in order to ensure a constant generator mode in automated electric drive systems, where the primary energy converter is an uncontrolled rectifier, it is expedient to install an energy discharge circuit in the DC link. References 18, figures 14.

Reverse Conduction Loss Minimization in GaN‑Based PMSM Drive

Gallium nitride (GaN) devices are becoming more popular in power semiconductor converters. Due to the absence of the freewheeling substrate diode, the reverse conduction region is used in GaN transistors to conduct the freewheeling current. However, the voltage drop across the device in the reverse conduction mode is relatively high, causing additional power losses. These losses can be optimized by adequately adjusting the dead-time issued by the microcontroller. The dead-time loss minimization strategies presented in the literature have the common disadvantage that either additional hardware or specific converter data are needed for their proper operation. Therefore, this paper’s motivation is to present a novel dead-time loss minimization method for GaN-based high-frequency switching converters for electric drives that does not impose additional requirements on the hardware design phase and converter data acquisition. The method is based on optimizing the current controllers’ output with a simple perturb-and-observe tracker. The experimental results show that the proposed approach can minimize the dead-time losses over the whole drive’s operating range at the cost of only a moderate increase in software complexity.

Energy Optimization of the 'Shore to Ship' System-A Universal Power System for Ships at Berth in a Port.

One of the most effective methods of limiting air pollution emissions by ships at a berth in a port is the power connection of ships to the on-shore system. “Shore to Ship” (STS)—A universal system for the connection of the ship’s electrical power network with the on-shore network—ensures the adoption of the voltage and frequency of the on-shore network for the exploitation of various types of ships in the port. The realization of such a system is possible due to the use of semiconductor technologies during the construction of mechatronic systems (i.e., systems that ensure the maintenance of electricity parameters). The STS system ensures energy efficiency for high-power ship systems through the use of an active semiconductor converter. This article presents an analysis of steady state electromagnetic and energy processes, allowing the determination of the active and reactive power and losses in the STS system. The presented analytical research enables the development of a control algorithm that optimizes the system energy efficiency. In the article, the control methods allowing the optimization of the energy characteristics of the system are considered and investigated. On the basis of theoretical studies, a model was developed in the Matlab-Simulink environment, which allowed us to study steady and transient processes in the STS system in order to reduce losses in power lines and semiconductor converters.

Improving the Reliability of Semiconductor Converters

This paper considers the opportunities for improving the reliability of power semiconductor converters by increasing the installed capacity margin and modifying the configuration of power circuit diagrams. As shown by regression analysis, the unit cost of an autonomous voltage inverter with an increase in the installed capacity of the frequency converter rises by about 25%. It is shown that the machine and the semiconductor converter are used most efficiently in six phases, whereas the number of valves in the semiconductor converter is 4m, where m is the number of phases. A further increase in the number of phases does not significantly reduce the phase current, but significantly increases the number of keys in the valve converter. It is shown that an increase in the phase of power circuit layouts allows using the electric machine more fully in terms of capacity and reduce the phase current in semiconductor converters by more than twofold. It is established that the new solutions allow reducing by almost twofold the number of failures in electric drives of more than 500 kW in capacity, while the costs of power electric equipment increase by no more than 25%.