一种新型串联混合型有源电力滤波器

提出一种新型可调电抗器的控制方式,其基本思路为:检测变压器一次侧的电压作为参考信号,采用一个电力电子逆变器跟踪该电压产生一个可调电压,并将该可调电压施加到变压器的二次侧,则变压器一次侧呈现为可调电抗器。将该可调电抗器应用到有源电力滤波器中,提出了一种新型串联混合型有源滤波器,可调电抗器串联在电力系统和谐波源之间时,检测变压器一次侧的谐波电压并采用电力电子逆变器产生一个谐波电压施加到变压器的二次侧,当施加到二次侧的谐波电压和一次侧的谐波电压满足一定关系时,则变压器一次侧对基波呈现变压器一次侧的短路阻抗,而对于谐波呈现为一个高阻抗,起到了隔离谐波的作用。该滤波器具有逆变器容量小、滤波效果好等优点。采用电压型谐波源和电流型谐波源的实验结果证明了该原理的有效性。

A Novel Series Hybrid Active Power Filter

A novel variable reactor based on transformer is proposed. In the variable reactor, a transformer is chosen, the primary winding voltage is detected and functions as a reference signal. A voltage source inverter is adopted to generate an adjustable voltage, which is applied across the secondary winding of the transformer. When the secondary controlled voltage is proportional to the primary winding voltage, the equivalent impedance of primary winding of the transformer will change continuously. The novel variable reactor can be applied to an active power filter. When the variable reactor is connected in series between the power utility and harmonic source, check the harmonic voltage of the primary winding and a voltage source inverter is used to follow so as to generate a voltage, which is applied across the secondary winding of the transformer. When the applied harmonic voltage and the fundamental current component of the power utility satisfy a definite relation, the series transformer will appear as a very low impedance to the fundamental harmonic and high impedance to harmonics. The novel series active power filter features low capacity, excellent filtering characteristics and easier strategy. The experimental results from two types of harmonic sources have verified the validity of the novel series active power filter. This work is supported by National Natural Science Foundation of China (No. 51477060, No. 51277081).