The controlled reactive-power compensator of an electric locomotive

A device for the precise compensation of the reactive power of an electric locomotive is considered. The device is designed based on a passive compensator, a boosting transformer and a self-commutated voltage inverter. The simulation of various locomotive operation modes proved the high efficiency of the suggested compensator design.     

静止无功补偿器对电力系统性能改善的综述

随着电力电子技术、微处理技术和控制技术的发展,柔性交流输电系统FACTS(Flexible AC Transmission System)的出现,为电力系统急待解决问题提供了新的手段或策略。静止无功补偿器(SVC)作为FACTS家族的成员之一,对电力系统性能的改善也已取得了可喜的成绩。因此,从静止无功补偿器提高稳态输送容量、提高暂态稳定性、增强系统阻尼抑制低频振荡、缓解次同步谐振、预防电压不稳定或控制电压的波动、改善直流输电系统的性能等六个方面进行综述。     

一种新型可连续调节的无功补偿装置

为实现工厂配电网大容量连续无功补偿,设计了一种基于S7-200 PLC的新型智能无功补偿装置.该装置充分利用S7 -200强大的模块功能、通信功能以及先进的程序结构,完成对电压、电流、功率因数等参数的测量,以实现无功功率补偿.以S7-200为控制器,接触器投切电容器进行粗调,感应调压器连续调节电容器两端电压进行细调,可...     

Novel reactive power controllers for the STATCOM and SSSC

The paper investigates the dynamic operation of both static synchronous compensator (STATCOM) and static synchronous series compensator (SSSC) based on a new model comprising full 48-pulse GTO voltage source converter for combined reactive power compensation and voltage stabilization of the electric grid network. These key FACTS devices are power electronic GTO converters connected in parallel or series with the power system grid and are controlled by novel decoupled controllers. The complete digital simulation of the STATCOM and SSSC within the power system is performed in the MATLAB/Simulink environment using the power system blockset (PSB). The STATCOM scheme and the electric grid network are modeled by specific electric blocks from the power system blockset while the control system is modeled using Simulink. Two novel controllers for the STATCOM and SSSC are presented in this paper based on a decoupled current control strategy to ensure stable operation of the STATCOM under various load excursions. A novel control scheme for the static synchronous series compensator (SSSC) is also implemented to provide a full controllable series compensating (buck/boost) injected voltage over a specified capacitive and inductive range, independently of the magnitude of the transmission line current. The series reactive compensation scheme with an external dc power supply can also compensate for any voltage drops across resistive component of the transmission line impedance. The novel decoupled controller uses a phase locked loop (PLL) with a novel reduced inherent time delay to improve the transient performance of the SSSC. The performance of both STATCOM and SSSC schemes connected to the 230 kV grid are evaluated. The proposed novel control schemes for the STATCOM and SSSC are fully validated by digital simulation.     

基于模糊PI的Boost PFC变换器的控制改进

为了减小开关变换器电流畸变对电网供电质量的影响,同时提高负载电压的动态响应性能,本文针对一个实际的单相功率因数校正装置设计改进控制方案。在建立小信号模型的基础上,根据其频域特性设计了相应的补偿器,并将电压环控制环节改进为模糊PI控制器。仿真运行结果表明,本文所设计的Boost PFC变换器的输出电压波形得到很好的改善,有效提高了电网供电质量。     

Application of an extreme control system to operate the reactive power compensator of an electric locomotive

Efficient use of fuel and energy resources is a high-priority area in the energy development strategy of railway transport up to 2030 adopted by OAO Russian Railways. Currently, ac electric locomotives with power rectifier–inverter transformers make up the majority of the usable fleet, in the range of 0.65 to 0.85. This is a cause of not only significant energy losses in the network of traction energy supply, but also restrictions affecting the speed of the locomotive. The energy characteristics of ac electric locomotives can be imptoved via compensation of the reactive power component. The reactive power compensator consists of series-connected capacitor C and inductance L connected to the secondary winding of the transformer. The LC circuit parameters are calculated for reactive power compensation of an electric locomotive in the nominal operation mode. In this article, a reactive power compensation device for electric locomotive made based on a regulated passive compensator was considered. The management of reactive power compensator is carried out by means of extreme control method. It is shown that the extreme control method for a reactive power compensator does not provide for direct calculation of the reactive power of an electric locomotive and significantly simplifies the management structure of a reactive power compensator.     

一种基于DSP的动态无功补偿装置

钢厂电弧炉等冲击性负荷接入电网,会引起电网电压波动与闪变、三相不平衡、电压电流波形畸变等电能质量问题。研究设计了一种基于DSP的滤波电容器＋晶闸管相控电抗器（FC＋TCR）型动态无功补偿装置。装置依据Steinmetz三相不平衡负荷的补偿原理,采用先进的DSP芯片TMS320F2812作为控制器的核心,保证了系统的实时响应速度和控制精度。试验显示,该装置能有效抑制电网电压的波动与闪变,改善系统三相不平衡度。     

复合型电流质量调节装置的研究

提出了一种级联型复合电流质量调节装置主电路拓扑,与传统拓扑相对比,采用了双PWM变换技术.PWM整流器为装置提供了稳定的直流电压,实现输入功率因数近似为1,同时实现了直流电压与输出电流的解耦控制.逆变侧采用谐波与无功统一补偿的控制策略,并采用输出电流直接PI闭环反馈控制,保证良好的电流跟踪效果.最后设计了一套基于DSP+FPGA控制的低压实验原理样机,验证了所提出的主电路拓扑及控制策略的可行性和有效性.     

一种新型级联多电平动态电压恢复器的研究

动态电压恢复器(DVR)是一种电压型电能质量补偿装置,串联在电网和负载之间,用于保障负载侧的电能质量.提出了一种新型级联多电平DVR,两个H桥功率单元级联构成一个逆变单元,并依靠整流电路给逆变单元直流侧电容器提供能量.装置采用电容器耦合方式串入电网,选用数字信号处理器(DSP)、现场可编程门阵列(FPGA)和复杂可编程逻辑器件(CPLD)构成控制系统.进行了详细的硬件和软件设计,实际运行测试结果表明,该级联多电平DVR响应速度快,能够迅速、有效地产生补偿电压,保证了负载侧的用电质量.     

10 kV配电网无功优化自动化控制系统设计

设计开发了一套基于功率因数和电压双控的、分布式的配电网无功优化自动化控制系统,作为控制参数的功率因数通过TCP/IP协议从调度自动化系统开放的服务端口获得,电压参数由下位控制机从现场的电压互感器获得。为保证10 kV干线出口功率因数和下位控制机现场电压合格,提出了补偿器投切的控制策略。详细介绍了上位机控制软件的架构和设计方法,采用多线程技术实现了该软件。上位机和下位控制机之间采用GPRS进行通信,制定了相应的控制协议。实践证明,所设计的10 kV配电网无功优化自动化控制系统使10 kV干线首端功率因数稳定在整定范围之内（0.95～1.00）,且系统运行可靠。     

新型静止无功补偿器稳定系统电压的研究

介绍一种基于PWM技术的新型静止无功补偿器。研究该补偿器在稳定系统电压方面的作用,分别对它在小扰动和大扰动情况下的工作状况进行分析,证明在工作范围内新型静止无功补偿器对系统电压有很大的支撑作用,可有效稳定系统电压。该补偿器具有结构简单、控制方便、响应速度快等特点。采用单机无穷大系统对补偿器进行开环和闭环控制仿真研究,验证该补偿器能维持装设点的电压并提高其电压稳定性。     

Design and Implementation of Adaptive Neuro–Fuzzy Inference System Based Control Algorithm for Distribution Static Compensator

This article focuses on the design and implementation of a distribution static compensator using an adaptive neuro–fuzzy inference system based controller. The distribution static compensator is controlled to provide power quality improvement, such as power factor correction, harmonics compensation, load balancing, and voltage regulation. Active and reactive power fundamental components of load currents are extracted using d-q theory. A distribution static compensator is realized using a voltage source converter. Both simulation and experimental results prove the effectiveness of the control algorithm under non-linear loads. The adaptive neuro–fuzzy inference system based controller works satisfactorily for power factor correction and harmonics reduction under balanced as well as unbalanced load conditions. Test results clearly depict the dynamics of the performance of the system under steady state as well as dynamics under load change and load unbalancing.     

变电站无功电压综合调节的模糊控制研究

研究了一种通过补偿电容器组和有载调压的主变压器相配合进行联合控制系统无功电压的方法。在推导出大型变电站的二次母线装设可投切的补偿电容器组和有载调压的主变压器相配合进行联合控制的模型基础上,提出了一种模糊控制方法。该系统将电压偏差和功率因数偏差作为模糊输入变量进行模糊化,经过模糊推理,并通过解模糊化运算给出控制信号作用于有载调压变压器和电容器组。结合实际电站系统参数对该系统进行仿真试验,仿真结果表明该控制系统稳定可靠,控制效果好。     

配电系统大功率交流电弧炉电能质量问题及方案治理研究

根据典型参数搭建电弧炉供配电系统，采用电弧炉现场录波数据作为负荷模型，以此为平台对电弧炉运行时给系统带来的电能质量问题进行详细分析，包括负荷谐波、不平衡以及母线电压波动等。以电能质量治理为目标，综合设计补偿方案：无源电力滤波器用于滤除负荷谐波电流，降低连接母线电压的总谐波畸变(total harmonic distortion, THD)，而变压器隔离的链式DSTATCOM配合瞬时电流分相控制方法，能够分相快速对负荷相电流进行控制，补偿负荷不平PSCAD/EMTDC中构建仿真系统，对基于现场数据模型的衡、抑制母线电压波动和闪变现象的产生。在电弧炉系统和补偿方案进行研究，最后给出了仿真结果用以表明所提治理方案的有效性。     

Design method considering the frequency band of the disturbance in the DC link voltage control system of hybrid electric vehicle driving systems

DC link voltage variable systems with DC/DC converter are used in hybrid electric vehicles for improving the power of the system by boosting the DC link voltage. Voltage feedback control using only proportional compensator has been proposed as a control method for the DC/DC converter. The control system can be easily designed, but there is a possibility that a steady‐state error occurs in the DC link voltage. In this paper, a proportional integral compensator is proposed to eliminate the steady‐state error of the DC link voltage in DC link voltage feedback controllers. In addition, when designing the gain of the compensator, the frequency band of the disturbance is considered. The proposed method is verified through experiments on the downsizing model.     

基于p-q-r理论的UPQC直接控制策略

阐述了p-q-r瞬时功率理论的原理,提出了基于该理论的统一电能质量控制器(UPQC)的直接控制策略,探讨了将其用于三相四线非线性及不平衡系统中的实现方法。着重介绍了p-q-r参考波形的产生方法,以及串联补偿电流和并联补偿电压的计算方法,并将其应用于非线性不平衡负载在电源电压不平衡及电压跌落情况下UPQC直接控制策略中。分析了控制策略的原理,推导出相关运算公式,给出了详细的控制框图。Matlab/Simulink仿真结果表明,采用该方法可以有效地消除非线性及不平衡负载对电网的影响,使电网输入功率因数为1,同时,串联补偿器隔离了电网电压对负载电压的扰动,并联补偿器给负载提供三相平衡及正弦的额定电压,不受电网电压变化的影响。     

基于UPQC的三相电流平衡补偿控制

统一电能质量控制器(UPQC)控制单元中既要控制静止同步无功补偿器(STATCOM)又要控制静止同步串联补偿器(SSC),灵活性和速动性降低且成本较高。对UPQC补偿装置进行具体的修改,UPQC的补偿原理主要是通过SSC交流侧输出一串联的电压以改变负载的实际工作电压,对STATCOM部分不要实施控制,故将UPQC中STATCOM部分的全控型电力电子器件换成二极管,从而得到了UPQC装置。以广东某一变电站为例,计算并用Matlab进行了仿真,结果表明,该补偿装置提高了控制的灵活性和速动性,且降低了成本。     

具有谐振抑制功能的新型SVC拓扑设计及控制方法

提出一种新型静止无功补偿器的拓扑结构及相应的控制方法。为了提高装置的补偿性能,引入了重复控制。针对10kV电网系统的10MVA不控整流负载,设计了新型静止无功补偿系统。仿真结果表明:新型静止无功补偿器能有效抑制无源滤波器与电网发生的谐振,具有谐波补偿精度高、响应快的特点,适用于高压大容量无功功率和谐波补偿的场合。     

基于PIC的TSC型动态无功补偿器

以PIC18F4520单片机为控制核心,采用电压、电流互感器和有效值检测电路检测电网参数,运用C语言编程,开发了一种适用于低压配电网的晶闸管投切电容器(TSC)型动态无功补偿器,实现无功功率和功率因数相结合的控制策略,避免轻载时投切振荡。通过控制晶闸管导通时刻投切电容器,实现功率因数的提高和电能质量的改善,具有动态响应快、无投切冲击等优点。试验结果证明,该TSC型动态无功补偿器硬件电路设计合理,整个装置运行稳定、可靠。     

电器试验中计算机数据检测与处理技术

如何利用计算机对有触点电器试验中的电气参数的数据进行检测、处理与显示,如电压、电流、频率和功率因数等参数,是计算机控制电器试验装置的关键技术之一。先介绍电器试验中的电压、电流信号的计算机检测技术;然后介绍采用快速傅立叶变换（ＦＦＴ）计算电压频率和功率因数的方法。