基于混合静止能量的虚拟转动惯量控制技术

首先在频率动态变化过程中,建立蓄电池的电池储能、超级电容器的电容储能与同步发电机的机械动能间的能量转换关系,阐述源于2种静止能量的混合储能系统的虚拟转动惯量的定义。其次,根据蓄电池和超级电容器的充放电特性,利用2种储能单元间的功率协同调节,提出含电池储能与电容储能的虚拟转动惯量的控制策略。该控制策略通过监测系统频率波动,根据2类储能元件的功率调节特性及荷电状态,协同调用2种静止能量,以模拟同步发电机组的惯性响应。最后,通过搭建含混合储能的光伏微电网仿真系统,验证了所提控制策略能够充分利用混合储能设备中存储的静止能量快速虚拟出惯性响应,显著改善系统频率的稳定性。

Virtual moment inertia control based on hybrid static energy storage

Firstly, the energy conversion relationship between battery energy storage, capacitor energy storage of super-capacitors and mechanical kinetic energy of synchronous generator is established in the process of frequency dynamic fluctuation, and the definition of virtual inertia of HESS(Hybrid Energy Storage System)derived from two kinds of static energy is defined. Secondly, based on the charging and discharging characteristics of batteries and super-capacitors, a HESS cooperative control strategy is proposed by using power co-regulation between two energy storage units. By monitoring the frequency fluctuation of the system, the control strategy transfers energy of battery and super-capacitors to imitate inertial response of synchronous generator in consideration of characteristic of power control and SOC(State Of Charging) by monitoring frequency fluctuation. Finally, a photovoltaic micro-grid containing HESS is set up to validate the effectiveness of the control strategy. The simulative results show that the strategy can make full use of the static energy stored in HESS to rapidly virtualize the inertial response and significantly improve the frequency stability of system.