| 引用本文: | 张 良,闫凯宏,冷祥彪,吕 玲,蔡国伟.基于SOC下垂控制的独立直流微电网协调控制策略研究[J].电力系统保护与控制,2021,49(12):87-97.[点击复制] |
| ZHANG Liang,YAN Kaihong,LENG Xiangbiao,LÜ Ling,CAI Guowei.Research on coordinated control strategy of an autonomous DC microgrid based on SOC droop control[J].Power System Protection and Control,2021,49(12):87-97[点击复制] |
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| 摘要: |
| 储能系统(ESS)作为独立直流微电网的关键组成部分，其主要由多组储能单元(ESUs)组成。针对多组ESUs荷电状态(SOC)均衡速度较慢，在SOC均衡过程中会产生母线电压偏差问题，提出一种改进SOC下垂控制策略。首先，该控制策略根据各储能单元(ESU)的充放电状态和SOC值寻找最优下垂曲线，合理分配负荷功率，减小母线电压偏差。然后通过确定主储能单元进行功率再分配，并在允许范围内动态调整下垂系数，使系统快速收敛到均衡状态，进一步减小该过程中产生的母线电压偏差。此外，考虑当ESS因满充等原因退出运行时，ESS稳压变为光伏系统稳压，光伏系统由变步长MPPT控制切换为带有前馈补偿的下垂控制，确保母线电压稳定和微电网安全运行。最后利用Matlab/Simulink搭建仿真模型，仿真结果表明所提控制策略可在保证SOC快速均衡的前提下，减小母线电压偏差，维持独立直流微电网的稳定运行。 |
| 关键词: 直流微电网 协调控制 幂指数下垂控制 电压前馈补偿 荷电状态 直流母线电压 |
| DOI：DOI: 10.19783/j.cnki.pspc.200734 |
| 投稿时间：2020-06-27修订日期：2020-08-15 |
| 基金项目:国家自然科学基金项目资助(51607031)；吉林市
科技创新发展计划项目资助(20190104138) |
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| Research on coordinated control strategy of an autonomous DC microgrid based on SOC droop control |
| ZHANG Liang1,YAN Kaihong1,LENG Xiangbiao2,LÜ Ling1,CAI Guowei1 |
| (1. School of Power Engineering, Northeast Electric Power University, Jilin 132012, China; 2. China Southern Power
Grid Energy Development Research Institute Company Limited, Guangzhou 510670, China) |
| Abstract: |
| As a key component of the autonomous DC microgrid, the Energy Storage System (ESS) is mainly composed of multiple Energy Storage Units (ESUs). There is a problem in that the State-Of-Charge (SOC) equalization speed of multiple ESUs is slow, and a large bus voltage deviation will be generated during the SOC equalization process. Here we propose an improved SOC droop control strategy. First, the control strategy determines the optimal droop curve according to the charging and discharging state of each Energy Storage Unit (ESU) and the SOC value, distributes the load power reasonably, and reduces the bus voltage deviation. Then, by determining the main energy storage unit for power redistribution, and dynamically adjusting the droop coefficient within the allowable range, the system quickly converges to an equilibrium state, and the bus voltage deviation generated by this process is reduced. In addition, when the ESS is out of operation, the photovoltaic system stabilizes bus voltage, and the photovoltaic system is switched from variable step MPPT control to droop control with feedforward compensation to ensure bus voltage stability and safe operation of the microgrid. Finally, the simulation results in Matlab software indicate that the proposed control strategy can reduce the bus voltage deviation and maintain the stable operation of the autonomous DC microgrid while ensuring the rapid equilibrium of the SOC.
This work is supported by the National Natural Science Foundation of China (No. 51607031) and the Science and Technology Innovation and Development Program of Jilin City (No. 20190104138). |
| Key words: DC microgrid coordinated control power index droop control voltage feedforward compensation state-of-charge DC bus voltage |
