Abstract: The instantaneous power of single-phase inverter load contains double frequency pulsating power component,which leads to the existence of second harmonic current in the input source. Taking PV-storage microgrid as an example,the harmonic current suppression method is proposed based on notch filter and quasi-proportional resonant controller. Under the action of above two controllers,the inductor branch shows high impedance at double frequency and low impedance at non-double frequency,which not only realizes the second harmonic current suppression,but also meets the dynamic needs. Aiming at the problems of poor dynamic performance and reducing harmonic suppression ability caused by improper controller parameters,an optimization strategy of suppression parameter group based on particle swarm optimization（PSO）is proposed. Since PSO has the advantages of high accuracy and fast convergence speed,it is convenient to obtain the optimal suppression parameter group,which takes dynamic quality,steady state and harmonic suppression ability into account. The experimental results verify the effectiveness of proposed method and optimization strategy.