有源电力滤波器在不同的应用场合需为负载提供不同的无功功率。为此,提出了一种有源电力滤波器输出无功的可控方法。该方法利用电网负载电流或电网电压产生基波因子,再和电压控制器的输出相乘产生电网电流的控制信号,使得有源电力滤波器能够在滤除谐波时有选择性地补偿无功功率,可以补偿无功或不补偿无功,克服了传统有功平衡控制方法只能实现谐波和无功功率同时补偿（不适合应用于大容量无功功率负载）的缺点,适合于更多的应用场合;并且该方法无需坐标变换,算法简单;此外,该方法还不需要锁相环电路,硬件成本低。实验结果验证了该方法的有效性和正确性。“,”To meet the requirments of various applications of active power filter, a direct detecting method for fundamental component of load current was proposed to produce the reference current. The fundamental factor was abstracted from the load current or the supply voltage, and was multiplied the fundamental component or the fundamental active component of load c filter can eliminate harmonic together with full-compensation of reactive p method overcomes the disadvantages of the conventional active power ba reactive power when eliminating harmonic. Additionally, the experimental is effective and simple. by output of voltage controller to obtain urrent. As a result, shunt active power ower and only eliminate harmonic. This lancing method which must compensate results demonstrate the proposed method