多约束储能自适应控制及电能质量提升方法

Multi-constraint adaptive control strategy for energy storage based on VSG

由于风电、光伏等可再生能源发电的不稳定性,可再生能源发电与负荷需求的时空错配给电网的安全可靠运行带来了新的问题。为了解决新能源高比例接入下的电能质量问题,同时保证储能的安全稳定运行,提出了一种综合考虑储能荷电状态(state of charge,SOC)和电能质量提升的多约束储能自适应控制策略。首先,通过Logistic回归模型和指数函数模型分别分析了储能SOC、频率变化率和虚拟惯性之间的动态联系,建立了储能系统运行安全约束分析和频率变化率约束模型,并加权得到储能系统虚拟惯量的自适应控制规律;然后,针对电压越限和电压波动问题,构建了基于节点电压约束模型的储能逆变器功率因数角自适应控制规律;最后,结合某县实际储能工程现状,仿真验证了所提控制策略能够根据储能SOC和频率变化实时改变储能功率输出,快速响应频率波动,有效抑制电压越限和电压波动,有力保障储能并网系统的安全稳定运行。

Due to the instability of renewable energy power generation such as wind power and photovoltaic,the temporal and spatial mismatch between renewable energy power generation and load demand brought new problems to the safe and reliable operation of the power grid.In order to solve the power quality problem under the high proportion of new energy access,a multi-constrained ESS adaptive control strategy is proposed,which comprehensively considers the state of charge(SOC)of ESS and the improvement of power quality.Firstly,the dynamic relationship among SOC,frequency change rate and virtual inertia of ESS is analyzed by Logistic regression model and exponential function model,respectively.The operation safety constraint analysis and frequency change rate constraint model of ESS are established,and the adaptive control law of virtual inertia coefficient of ESS is obtained by weighting.Secondly,aiming at the problem of voltage over-limit and voltage fluctuation,an adaptive control law of power factor angle of ESS inverter based on node voltage constraint model is constructed.Finally,combined with the actual situation of a ESS project,the simulation verifies that the proposed control strategy can change the ESS power output in real time according to the ESS SOC and frequency changes,quickly respond to frequency fluctuations,effectively suppress voltage over-limit and voltage fluctuations,and effectively guarantee the safe and stable operation of the ESS grid-connected system.