新型电力系统的惯性低,虚拟直流电机控制可以加强系统惯性和阻尼.多储能变换器应该考虑荷电状态(State of charge,SOC)均衡问题,提高系统稳定性.针对虚拟直流电机控制的多储能SOC均衡问题,利用直流电机机端电压和电枢电流的下垂特性,提出引入SOC离差及变均衡系数的变电枢电阻控制;针对下垂引起的电压偏移问题,采用虚拟直流电机转速补偿,用母线电容瞬时功率替代传统虚拟直流电机控制中电压PI控制,给定系统功率需求,减少比例积分环节个数.以两台蓄电池为例,在 Simulink 中进行仿真,并与参考文献的变电枢电阻函数对比可知,所提控制策略可抑制直流母线电压跌落,调节SOC均衡过程,提高其均衡速度和精度.
Virtual DC Motor SOC Equalization Control
The new power system has low inertia,and virtual DC motor control can strengthen system inertia and damping.State of charge(SOC)equalization should be considered in multi-energy storage converters to improve system stability.Aiming at the multi-energy storage SOC equalization problem of virtual DC motor control,using the drooping characteristics of the DC motor terminal voltage and armature current,the variable armature resistance control with SOC dispersion and variable equalization coefficient is proposed.In view of the voltage offset problem caused by droop control,the virtual DC motor speed compensation is used.The voltage PI control in traditional virtual DC motor control is replaced by instantaneous power of the bus capacitor to give the system power requirements,which reduces the number of proportional integration links.Taking two batteries as an example,simulated in Simulink,and compared with the armature resistance function of the reference,it can be seen that the proposed control strategy can suppress the DC link voltage drop,adjust the SOC equalization process,and improve its equalization speed and accuracy.
Virtual DC motor controlmulti energy storagevariable armature resistancespeed compensationSOC balance
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维普
