基于Matlab的变频器输出RLC dv/dt滤波器仿真

针对工业变频器驱动感应电机采用长电缆时会产生电压反射的现象,导致感应电机端过电压和高频阻尼振荡的发生,使电机绝缘加速老化,最终造成绝缘击穿等事故的问题,研究了将传输线理论结合电机系统模型分析应用到RLC dv/dt滤波器的详细设计中。首先通过分析长电缆传输时,变频器PWM输出脉冲对电机侧电压的影响,建立了"传输线—滤波器"一体化系统模型,并进行了具体的计算,得出了二阶RLC dv/dt滤波器的基本设计方法,推导出了相应公式以及电缆长度、电缆特性参数、电压反射系数等对滤波器参数的影响,最后用Matlab进行了仿真,并对按照该方法设计的产品进行了模拟实际工况试验测试,将仿真结果与试验数据进行了比较,两者基本吻合。研究结果表明,针对变频器输出dv/dt滤波器的设计,采用该方法具有可行性、有效性和高准确性。

Simulation and design of inverter output RLC dv/dt filter based on Matlab

Aiming at the problems of when as the long cable was connected industry inverter to driving induction motor,led to the voltage reflection was happened,which caused overvoltage and high-frequency damped oscillation,aged and break-down the motor insulation and so on,the transmission line theory with motor system model analysis was studied and applied to RLC dv/dt filters design.First,by analyzing the long cable transmission,the motor side voltage was effected on the inverter PWM output pulse voltage,the transmission line-filter integrated system model was established,deduced specifically,and the fundamental method was presented to design of tow order RLC dv/dt filter.The corresponding formulas were derived and the cable length,cable parameters,voltage reflection coefficient parameters of the filter were found.Finally simulation with Matlab,and the design of the product in accordance with this method were tested specifically.The simulation results were verified by experimental data.The experimental results show that about the method of dv /dt filter design.was feasibility effectiveness and high accuracy.