电力系统中的电力电子转换器设计与优化

电力系统是现代社会不可或缺的基础设施,而电力电子转换器则是电力系统中的核心关键组件。本论文旨在研究电力电子转换器的设计与优化,探索如何提高电力转换效率、降低损耗、增强系统稳定性以及解决潜在的电磁干扰问题。本文主要介绍电力电子器件的基本工作原理,针对不同的电力转换需求,提出了几种常见的电力电子转换器拓扑结构并深入探讨其设计与优化方法。此外,还讨论了电力电子转换器在可再生能源系统中的应用以及与现有电力系统的兼容性问题。

工业大电流负载的电力转换器中IGBT的应用分析

本文介绍了用于工业真空直流电弧炉的电力转换器,分析了带参量电流源的功率转换器和基于带 IGBT 开关的开关模式电源(SMPS)单元转换器的能量性能。带有SMPS单元的转换器具有更高的效率,从而降低了单位能耗。为了提高向大电流直流负载供电的工业电网的电能质量, 分析了一种基于电流源型有源整流器的变频器。

配网智能设备中电力电子智能变压器的研究

随着灵活交流输电系统(flexible AC transmission system,FACTS)(即电力电子)设备的开发以及在高压及超高压输电系统的应用,电力电子元件和其他高新技术材料成本的下降以及近年来对智能电网的开发,已研发出大量如电力电子智能变压器、故障电流限制器、带储能功能的静态同步补偿器、动态电压恢复器及有源电力滤波器等智能配网设备。部分设备如静态同步补偿器、动态电压恢复器和有源电力滤波器已应用于配网系统,部分设备如电力电子智能变压器和故障电流限制器正处于研发的后期和试运行阶段。智能配网设备的广泛应用将为配电系统自动化和智能化的实现、建设和快速发展做出巨大贡献。该文将主要探讨电力电子智能变压器的基本原理、最新的研发、应用及展望。

A new high-performance AC/DC power factor correction switching converter based on one-cycle control technology and active floating-charge technology

A new family of converters,high-performance AC/DC power factor correction(PFC) switching converters with one-cycle control technology and active floating-charge technology,was derived and experimentally verified.The topology of a single-phase CCM and DCM Boost-PFC switching converter was also analyzed.Its operating prniciples and control methods were expounded.Based on these,a new type of AC/DC switching converter circuits for PFC combined with one-cycle control technology was presented herein.The proposed AC/DC switching converter significantly helps improve the converter efficiency and its power factor value.

Study on ultracapacitor-battery hybrid power system for PHEV applications

For the battery only power system is hard to meet the energy and power requirements reasonably, a hybrid power system with uhracapacitor and battery is studied. A Topology structure is analyzed that the uhracapacitor system is connected with battery pack parallel after a bidirectional DC/DC converter. The ultracapacitor, battery and the hybrid power system are modeled. For the plug-in hybrid electric vehicle （PHEV） application, the control target and control strategy of the hybrid power system are put forward. From the simulation results based on the Chinese urban driving cycle, the hybrid power system could meet the peak power requirements reasonably while the battery pack＇ s current is controlled in a reasonable limit which will be helpful to optimize the battery pack＇ s working conditions to get long cycling life and high efficiency.

A Review of Direct Driven PMSG for Wind Energy Systems

This paper presents a comprehensive overview study of the DDPMSG （direct driven permanent magnet synchronous generator） for wind energy generation system. Wind turbine controls are provided. The PMSG （permanent magnet synchronous generator） is introduced as construction and model. Configurations of different power converters are presented for use with DDPMSG in wind systems at variable speed operation and maximum power capture. Control techniques for the system are discussed for both machine-side and grid-side in details. Grid integration is provided with focus on how to insure power quality of the system and the performance at disturbances.

Fault Ride-Through Capability of Full-Power Converter Wind Turbine

In order to ensure power system stability, modern wind turbines are required to be able to endure deep voltage dips. The specifications that determine the voltage dip versus time are called fault r/de-through （FRT） requirements. The purpose of this paper is not only to examine the FRT behavior of a full-power converter wind turbine but also to combine the power system viewpoint to the studies. It is not enough for the turbine to be FRT capable; the loss of mains （LOM） protection of the turbine must also be set to allow the FRT. Enabling FRT, however, means that the LOM protection settings must be loosen, which may sometimes pose a safety hazard. This article introduces unique real-time simulation environment and proposes an FRT method for a wind turbine that also takes the operation of LOM protection relay into account. Simulations are carried out using the simulation environment and results show that wind turbine is able to ride-through a symmetrical power system fault.

On Impulse Switching Functions of Inverters as an Orthogonal System

The paper deals with impulse switching function which are used as exciting functions of one- and multidimensional state-space models of power electronic converters. Obviously, these functions are harmonic but using power converters they can be strongly non-harmonic, sometimes piecewise constants with zero spaces between them. Then, one deals with power series of time pulses. The impulse switching functions which are orthogonal ones can be derived from these series. The new impulse switching functions are created using Z-transform, inverse Z-transform and numerical series/sequences. The impulse switching functions created this way can be used for both steady- and transient state investigation of converters.

Reliability Comparison of MPPT Converter in DCM and CCM Operation

The reliability plays an important role in power electronic systems by which the number of system failures, repair costs, guarantee and etc. are estimated. In this paper first, a boost Maximum Power Point Tracker （MPPT） converter is simulated in Discontinues Conduction Mode （DCM） and Continuous Conduction Mode （CCM） under different output power ratings. For these simulations, all of the inherent parameters of MOSFET and diodes are applied according to the actual types. Then, reliability calculation is done based on MIL-HDBK-217 handbook. Results have shown that the MPPT converter would have better performance from reliability point of view in CCM operating mode.

High Performance Double-Interleaved Dual Boost Converter and 3 Phase Grid Connected Converter for Wind Turbine

This paper proposes a high performance double-interleaved dual boost （DIDB） technique to solve the problems of high ripple current, large inductor size and the requirement of step-up transformer in many case found in the conventional DC-DC boost converter. The 3-phase grid connected converter with decoupling control give an independent control between active and reactive power using the load current feed-forward. With this technique, the disturbance rejection and the output power quality can be improved. Experiments are conducted with three case studies： 1） a test of the DIDB converter to determine current ripple and voltage gain, 2） a test of the 3-phase grid connected converter to determine DC-link voltage regulation, power factor and total harmonic distortion （THD）, and 3） a test of the overall system with a 7.5 kW wind turbine simulator by step and various input wind speeds to determine the output power at the grid side and verify the maximum peak power tracking （MPPT） performance. The results can confirm that the DIDB converter gives lower ripple current and higher voltage gain than the conventional converter. For the grid side, the 3-phase grid connected converter can regulate the DC-link with fast dynamic response to disturbance rejection and low overshoot while complying with the THD standard defined in IEEE 519-1992. In addition, the MPPT controller is able to achieve the maximum energy capture with the various input wind speeds.