【作者】 刘丽丽；

【导师】 田铭兴；

【作者基本信息】 兰州交通大学 ， 电工理论与新技术， 2010， 硕士

【摘要】 由于非线性负载的大量应用,电网的谐波污染问题日益严重,并由此产生了一系列的电能质量问题,同时用户对电能质量又提出了更高的要求,因而谐波治理问题已迫在眉睫。混合有源电力滤波器因其较好地克服了无源电力滤波器和有源电力滤波器各自的缺点并实现了优势互补,以较低的成本获得了较好的滤波效果和稳定性,而日益受到人们的重视,成为高压、大功率电力系统的主要谐波抑制装置。本文在兰州供电公司110kV变电站10kV馈电网的谐波治理背景下,对新型并联混合有源电力滤波器的电气参数设计方法进行深入研究。首先,详细分析有源电力滤波器的各种拓扑结构,并在此基础上选择适合高压、大功率系统的有源电力滤波器拓扑结构进行深入分析；研究新型并联混合有源电力滤波器在检测电网谐波电流控制方式、检测负载谐波电流控制方式及两者相结合的复合控制方式下的工作原理。其次,采用一种改进的遗传算法来优化新型并联混合有源电力滤波器中无源电力滤波器的电容参数,以投资成本、无功补偿性能及滤波效果三方面作为目标进行综合考虑；利用阈值制约两个适应度函数,一方面使得种群进化逐步进入约束空间,另一方面又保证具有潜力的染色体不会被过早地淘汰；同时,以不同的概率对染色体进行选择操作,使种群朝着三个目标最佳协调点的方向进化；引入混沌算子来克服早熟收敛现象；编写MATLAB语言的多目标优化程序,求得无源电力滤波器的电容参数。再者,根据无源部分电气参数的优化结果对系统有源部分的参数进行较为详细的设计,包括有源滤波器、耦合变压器、输出滤波器及直流侧电容；利用MATLAB/SIMULINK软件建立混合滤波系统的仿真模型并进行仿真,仿真结果表明采用多目标优化方法设计的滤波器参数具有较好的滤波效果；根据新型并联混合有源滤波系统的参数优化流程设计图形用户界面,使用户的学习和操作更为方便。最后,推导最小电容安装容量法和无功补偿容量法的工程方法设计无源滤波器参数的过程,并得出滤波器参数的工程设计结果；从经济性、无功补偿性能和滤波效果三方面分别对工程设计方法和多目标优化方法得出的混合滤波器参数进行性能对比分析。结果表明,由工程设计方法得出的滤波器参数只能满足部分设计指标的要求,而通过多目标优化方法得出的滤波器参数具有良好的经济性和谐波抑制性能,并兼顾无功补偿的作用,验证多目标优化方法设计新型并联混合有源电力滤波器参数的正确性和优越性。更多还原

【Abstract】 Because of the wide-range application of nonlinear load, the harmonic pollution to power system has become more and more serious, and has brought a series of power quality problems. At the same time, higher demands on power quality are proposed by users. As a result, the problem of harmonic controlling is imminent. Novel Parallel Hybrid Active Power Filter (NPHAPF) has been paid more and more attention and become the most important harmonic eliminating device in the high voltage and big power system, because it overcomes the shortcomings of passive power filter and active power filter, and gets a better filtering effect and stability at lower cost. Under the harmonic eliminating background of lOkV power distribution network at 11OkV substation in a power company, a profound study is penetrated on the parameters design of NPHAPF.Firstly, the topology which is appropriate for high voltage and big power system is selected based on the analyses of various active power filter topology, and analysis it deeply. Furthermore, the work principles under the command mode of testing power system harmonic current, load harmonic current and a combination of them are studied.Secondly, an improved genetic algorithm is proposed to solve the problem of passive power filter capacitor parameters of NPHAPF, and the objective is set by considering invest, reactive power compensation and filtering effects. Using the threshold values to restrict these two fitness functions, on one hand, making the populations evolve gradually into the constrainted space, on the other hand, making the potential chromosomes will not be eliminated untimely. At the same time, the chromosomes selection operations are produced by different probabilities to make sure the population evolution towards the direction of the best tuning point of three targets. Besides, the chaos operator is introduced to overcome the phenomenon of premature convergence. The PPF capacitor parameters are realized by the multi-objective optimal program in MATLAB.What’s more, a detail analysis is paid on the parameters design of the active part according to the optimal result of passive filter, including active filter, coupling transformer, output filter, and DC side capacitor. Based on the software of MATLAB/SIMULINK, a simulation model of hybrid filtering system is established and simulated, and the simulation results show that the designed parameters by multi-objective optimal method have a better filtering effect. Furthermore, the graphical user interface is designed based on the parameters optimal process of NPHAPF, which makes users learn and operate more conveniently.Finally, the theories of engineering design methods are deduced to obtain the filter parameters, such as minimal capacitor installed capacity and reactive power compensation capacity method. Then, using the designed parameters by multi-objective optimal method and engineering design methods, the hybrid filter performances are compared on the aspects of cost, reactive power compensation and filtering effect. The results show that the filter parameters which are designed by engineering methods only meet some demand of the design indicators. However, the multi-objective optimal method can get a good effect on the economy and harmonic elimination, as well as the reactive power compensation, thus reveals its correctness and superiority of multi-objective optimal method for NPHAPF parameters design.更多还原