三相有源电力滤波器开关控制策略的研究

发布时间：2018-01-14 10:42

本文关键词：三相有源电力滤波器开关控制策略的研究　出处：《兰州交通大学》2014年硕士论文　论文类型：学位论文

【摘要】：随着电力电子技术和电力电子器件的飞速发展，大量的非线性负载被接入到电网中，由此注入电网系统的大量谐波带来了严重的电能质量问题。随着电网规模的逐渐扩大以及广大用户对电能质量的要求不断提高，如何抑制谐波以改善用电质量正在受到日益广泛的关注。不同于无源滤波等传统滤波方法，有源电力滤波器能够对谐波电流进行实时动态补偿从而达到较好的谐波抑制效果。本文的研究对象是三相三线制并联型有源电力滤波器，通过相应的检测方法和开关控制策略将补偿电流通过公共连接点注入电网，从而达到抑制谐波的目的。本文使用的谐波电流检测方法是基于无锁相环的同步检测法，这种检测方法可以在电网电压畸变的情况下对谐波电流进行较为准确的检测，仿真实验验证了这种方法的正确性和可行性。接下来本文对传统的滞环边带比较控制进行了研究，通过搭建仿真模型得到的波形可以看出其跟踪波形中存在毛刺，即存在局部电流失控现象。通过对滞环边带控制下的系统进行矢量分析，得出了电流局部失控的原因，即由于系统中的各相电流相互关联，所以以单个桥臂状态为控制目标的滞环边带比较控制策略不能通过单独控制某一相的开关状态使该相桥臂按期望值变化。最后本文研究了基于综合误差最小的无差拍控制策略，，分析和推导了该方法的预测机制和运算过程，最后通过Simulink进行了建模和仿真验证。对于直流侧电压控制部分，虽然传统的PI控制法应用较为广泛，但是该方法需要经过较为复杂的参数计算才能达到较优的控制效果。因此，在本文研究的滤波系统中，采用了基于有功功率平衡的控制方法来控制直流侧电容电压，这种方法简单易行，后续的仿真验证了这种控制方法的正确性和可行性。
[Abstract]:With the rapid development of power electronics and power electronics , a large number of nonlinear loads are introduced into the power grid , so the large amount of harmonic waves injected into the power grid system bring serious problem of power quality . As the scale of the power grid is gradually enlarged and the demand of the large number of users on the quality of electric energy is continuously improved , how to suppress the harmonic wave to improve the quality of power is becoming more and more extensive . Unlike the conventional filtering method such as passive filtering , the active power filter can dynamically compensate the harmonic current in real time to achieve better harmonic suppression effect . The research object of this paper is three - phase three - wire parallel active power filter , through the corresponding detection method and switch control strategy , the compensation current is injected into the power grid through the common connection point , so as to achieve the purpose of restraining harmonic . The harmonic current detection method used in this paper is based on a synchronous detection method without a phase locked loop . The detection method can accurately detect the harmonic current under the condition of voltage distortion of the power grid , and the simulation experiment verifies the correctness and feasibility of the method . For the DC side voltage control part , although the traditional PI control method is widely used , the method needs more complex parameter calculation to achieve better control effect . Therefore , in the filter system studied in this paper , the control method based on active power balance is adopted to control the DC side capacitor voltage , and the method is simple and easy , and the subsequent simulation verifies the correctness and feasibility of the control method .

【学位授予单位】：兰州交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN713.8;TM761

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