[关键词]
[摘要]
分布式电源在微电网中渗透率越来越高,其间歇性对系统电压稳定性的影响不容忽视。电力弹簧(ES)作为一种新型电压控制装置,能有效抑制关键负载(CL)两端的电压波动。为了减小负载变化对ES调压能力的影响,提出一种考虑非关键负载(NCL)变动的电力弹簧自适应控制策略。介绍了ES的拓扑结构及限制运行条件的理论基础;根据αβ坐标系变化的方法检测母线电压暂降,确定是否将ES投入系统;参考电压计算模块计算出需要提供的补偿电压后,与实际值的误差输入到PI控制器中,经人工鱼群算法(AFSA)动态调整PI控制参数,在保证CL电压稳定基础上缓解NCL变化对ES调压能力的影响。仿真结果表明:所提控制策略能够在保证CL电压稳定基础上有效缓解不同工况下负载变化造成的电压不稳定问题。
[Key word]
[Abstract]
The penetration rate of distributed power in the microgrid was higher and higher, and the impact of its intermittence on the stability of the system voltage could not be ignored. Electric spring (ES) was a new type of voltage control device that could effectively suppress voltage fluctuations across critical loads (CLs). In order to reduce the influence of load changes on the voltage regulation capability of ES, an adaptive control strategy of ES considering variation of noncritical load (NCL) was proposed. The topological structure of ES and the theoretical analysis of restricting operation conditions were introduced. The voltage sag was detected by the method of changing αβcoordinate system to determine whether the ES was put into the system. After calculating the compensating voltage with reference voltage calculation module, the error relative to the actual value was input into the PI controller. The PI control parameters were dynamically adjusted by artificial fish swarm algorithm (AFSA) to alleviate the influence of NCL variation on the basis of ensuring the stability of CL voltage. The simulation results showed that the proposed control strategy could effectively alleviate the voltage instability caused by load changes under different operating conditions on the basis of ensuring CL voltage stability.
[中图分类号]
V 242.3
[基金项目]
国家自然科学基金项目(61275038);上海市“科技创新行动计划”地方院校能力建设专项项目(19020500700)