Virtual DC Motor SOC Equalization Control

doi:10.11985/2024.01.018

Abstract

Abstract:

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.

Key words: Virtual DC motor control, multi energy storage, variable armature resistance, speed compensation, SOC balance

CLC Number:

TM33

XU Min, ZHAO Qiaoe. Virtual DC Motor SOC Equalization Control[J]. Journal of Electrical Engineering, 2024, 19(1): 169-176.

Figures/Tables 16

References 20

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参数	数值
母线电压参考值U_ref/V	400
蓄电池端电压U_bat/V	100
额定转速ω_n/(rad/s)	314
蓄电池1初始SOC	0.6
蓄电池2初始SOC	0.5
惯性系数J/(kg·m²)	8
阻尼系数D	2
转矩系数C_T	18.4
每极磁通Φ/Wb	0.069 8