强磁场装置有源直流滤波器设计

对强磁场装置电源所需的有源直流滤波器ADF(Active DC Filter)进行了设计,利用脉宽调制(PWM)及并联有源滤波技术提出了新的滤波方案。给出了系统结构并对工作原理进行了说明,论述了该系统的设计方法。根据其实际负载特性,通过检测负载端电压,利用电流的PWM控制技术产生所需电流,通过对负载侧的滤波电容进行充、放电调整负载端电压,从而实现负载电流的低纹波。基于传递函数建立了该系统的数学模型,并对控制系统进行了详细的分析,分析表明该系统具有良好的快速跟踪性能及对谐波很好的抑制效果。最后,给出了仿真结果,验证了该有源滤波器的良好性能,尤其对低次谐波的抑制更为明显。

Design of active DC filter for high magnetic field device

An ADF(Active DC Filter) is designed for the power supply of high magnetic field device,which applies a new scheme based on PWM(Pulse Width Modulation) and parallel active power filter technique.Its structure,principle and design method are presented.According to the actual load characteristics,ADF produces the required currents with PWM control technique and compensates the ripple current by detecting and adjusting the load voltage.By charging and discharging the capacitor at load side,the current ripple through the load becomes very low.Its mathematical model is established based on the transfer function,and the control system is analyzed in detail.Results show that,the system responds quickly and suppresses ripple effectively.Simulation results validate its good performance,especially in low-order harmonic suppression.