【作者】 徐明；

【导师】 周林；

【作者基本信息】 重庆大学 ， 电气工程， 2007， 硕士

【摘要】 非线性负载的大量使用,造成电力系统中的谐波问题日益严重,迫切需要对其进行治理。有源电力滤波器(Active Power Filter,简称APF)是目前治理谐波相当有效的装置之一,其谐波电流检测方法和控制方法是决定其性能的关键性环节。本论文就APF的控制方法进行了研究,主要内容如下:首先介绍了几种单周控制(One-cycle Control,简称OCC)策略在单相APF中的应用情况,分析了各自的原理,给出了各自的控制电路及电流波形,重点对它们进行了稳定性分析。分析结果显示,在相同的电路参数下,双向互补策略的稳定性最好,能够达到全局稳定。针对定时控制瞬时值比较法应用于APF时存在局部稳定性问题,本文运用双向互补思想,提出了一种双向互补的瞬时值比较法对其进行改进,并对此进行了仿真研究。仿真结果说明,与传统的定时控制瞬时值比较法相比,将这种控制方法应用于单相APF和三相APF中不仅能极大地扩展系统的稳定工作范围,而且能减小补偿电流误差。同时,在此基础上,提出了一种不需电流检测电路的双向互补瞬时值比较控制APF,这种APF参照双向互补单周控制APF结构,让电源电流跟随电压波形变化,因而不需电流检测环节,极大简化了电路结构。与双向互补单周控制APF相比,这种不需电流检测的双向互补瞬时值比较控制APF电路简单,控制方便,而且补偿效果好。仿真结果验证,不管是单相还是三相系统,这种APF都能很好地补偿谐波和无功电流。最后,在仿真基础上,对双向互补瞬时值比较控制的单相APF进行了实验研究,并设计调试了试验样机,结果验证了这种APF的可行性。更多还原

【Abstract】 The widespread use of nonlinear loads is leading to harmonic problem becoming increasingly serious in power system, so it is in urgent need of compensation for the harmonics. Recently active power filters (APF) is a viable equipment to eliminate the harmonics and its performance depends on the method and the control techniques. This paper studies control methods of APF and the main contents are as follows:At the beginning, several one-cycle control (OCC) strategies in single-phase APF are illustrated and their principles are presented in the paper, the stability of OCC approaches is analyzed and compared. The analysis results show that under same circuit parameters double-direction compensation control strategy is most stable, besides, by means of double-direction compensation control strategy the global stability can be realized.Because the time-control instantaneous comparison method has a problem of localized instability when it is used in APF, this paper presents an improved method based on double-direction compensation control strategy and researches its simulation. Simulation results verify that, compared with the typical time-control instantaneous comparison method, the stability region is enlarged and the error between compensating current and referenced signal is reduced by the double-direction compensation instantaneous comparison controlled APF in single-phase and three-phase system.Furthermore, double-direction compensation instantaneous comparison controlled APF without current-detection circuit is presented. The novel APF consults the OCC APF to let input current follow input voltage change and needn’t detect current, thus the system circuit simplification. In contrast with double-direction compensation OCC controlled APF, the double-direction compensation instantaneous comparison controlled APF without current-detection circuit has a simple circuit, an easy control and a good compensation performance. Simulation results prove that the harmonic and reactive current is eliminated by the proposed scheme not only in single-phase but also in three-phase system. Finally, the experimental research of single-phase APF with double-direction compensation instantaneous comparison control is built based on the simulation and experiment sample is obtained. The experimental results confirm the feasibility of this scheme.更多还原