【作者】 王刚；

【导师】 曾林锁； 程祥；

【作者基本信息】 沈阳工业大学 ， 电力系统及其自动化， 2007， 硕士

【摘要】 无功控制对于交流传输系统已经成为一个重要的课题。因为大多数负荷都消耗无功功率(例如感应电机)。负荷和负荷的功率因数的改变能引起终端电压的很大改变。这将导致由于电压过低而影响负荷功能的执行或者由于过电压引起绝缘的损坏。这就需要在适当的地方进行无功补偿。传统的无功补偿设备有同步调相机、固定容量的电容器、开关控制的并联电抗器等，这些设备可满足一定范围的无功补偿要求，但存在响应速度慢、故障维护困难等缺点，难以满足现代快速控制的要求。STATCOM是一种静止同步无功补偿器，它的容量或感应输出电流能独立于交流系统电压，STATCOM比SVC有着更快速和动态的反应，通常没有必要增加额外的滤波网络。目前，国内国际上所投入使用的STATCOM多为电压源逆变器型(VSI)，而另外一种基于电流源逆变器的STATCOM(CSI)也是一种潜在的拓扑结构，在国内和国外还没有被广泛的研究和应用，它通过直流侧的电感经逆变器输出电流来使STATCOM吸收和发出无功，达到无功调节的目的。与电压源型STATCOM相比，它可以直接控制于补偿电流，不需要与交流系统间有磁场的耦合。本文将主要进行以下工作：建立能反映装置主要特性的数学模型，我们可以采用输入输出的建模方法来建立STATCOM装置的数学模型；根据补偿器要实现的功能和应用的场合来决定采用开环控制、闭环控制或者两者相结合的控制策略；利用MATLAB附带的动态通用仿真软件包SIMULINK对其进行系统级建模仿真；电流源型STATCOM的软件和硬件的初步设计。本文阐述基于电流源逆变器(CSI)STATCOM的电路结构，工作原理，数学模型。它的特点是以通过控制电感线圈的电流来实现对无功的控制。电流源逆变器(CSI)STATCOM的优点在于对并联补偿电流的直接控制。这种结构不需要耦合磁铁。由于半导体的串联配置，导体损耗相对较高。但随着电力电子技术的快速发展，如果有更好的半导体器件的出现，这种电流源逆变器(CSI)STATCOM将具有广泛应用的潜力。更多还原

【Abstract】 Reactive power control has been an important issue since the emergence of the ac transmission system, because the most loads consume are reactive power (for example induction motors). The load and load power factor change can cause large amplitude variation in receiving end voltage, which will degrade the performance of the load due to the undervoltage or cause insulation damage to the load due to the overvoltage. So the compensation on proper location is necessary. Traditional reactive power compensation equipment, such as rotary condenser, capacitor, electric reactor, can suffice the demand of compensation, but it has many shortcoming, for example slow response speed and difficult maintenance of accident. So it is difficult for traditional reactive power compensation equipment to meet the demand of modern fast control. STATCOM is a static synchronous generator operated as shunt-connected static var compensator whose capacitive or inductive output current can be controlled independent of the ac system voltage. It has faster dynamic response than the SVC. Presently most of these commercialized STATCOMs are based on the voltage source inverter (VSI). Another potential topology that can be applied to STATCOM is current source inverter (CSI). It can absorb and generate reactive power through the current produced by converter. Compared with the voltage source converter STATCOM, it can control the compensation current and needn’t has magnetic Field Coupling with ac system.In this chapter, some work would be done as followed:(1) Derive the mathematical model of the STATCOM on the fundamental frequency model. We want to build the mathematical model that can reflect main character of CSC STATCOM and don’t pay attention to some device current at some time. So we use input and output modeling method to built the mathematical model of CSI STATCOM.(2) Design of control for CSI STATCOM. The control is based on the fundamental model of the CSI based STATCOM. There are two control objectives: one is to regulate the dc inductor current; the other is to design a controller to regulate the bus voltage. We decide to use open-loop control strategy or close-loop control strategy according to what CSI STATCOM function. (3) Do some simulation and experimental work on CSI STACOM and Simulation of the dynamics using SimuLink. According to the mathematical model have been built, we can do some simulation and experimental work using MATLAB and SimuLink.In this chapter, The advantage of the CSI topology is the direct control of the current for shunt compensation. No coupling magnetics are needed for this topology. Due to the configuration of semiconductors in series, the conduction loss is relatively high. If better semiconductors are available, this topology can be potentially widely used.更多还原