船舶直流电力系统负阻抗特性补偿控制策略

Control Strategy for Negative Impedance Compensation in Ship DC Power System

为解决船舶直流电力系统中恒功率负载负阻抗特性引起的母线电压谐振不稳定现象,提出两种基于输入电压前馈的负阻抗特性补偿控制策略。首先,利用小信号稳定性分析方法推导出系统稳定运行工况。然后,再推导出系统的输入、输出阻抗,通过阻抗稳定判据分析系统的稳定性。进而提出电压前馈的控制方法用于改善系统输入、输出阻抗之间的关系,提高系统的稳定性。最后,在MATLAB/Simulink中进行仿真试验,试验结果表明:基于负阻抗特性补偿的控制策略能够抑制直流母线电压的振荡,提高系统的稳定性。

Two negative impedance compensation control strategies based on input voltage feed forward is devised to solve the voltage instability caused by bus resonance.The steady state of system operation is determined through small signal stability analysis and the input impedance and output impedance are calculated.The stability of the system is analyzed according to the stability criterion based on the impedances.The methods to improve the stability through changing the ratio between the impedances by introducing voltage feed forward into the system are devised.Simulations are performed with MATLAB/Simu1 ink to verify the control strategies.