Research On Optimal Control Of Microgrid Energy Storage Inverter

With the energy shortage caused by the continuous development of society,microgrid distributed generation has become one of the effective solutions,so the energy storage system has attracted the attention of a wide range of researchers.The energy storage inverter is the core part of the microgrid energy storage system,and it is the key to realize the two-way energy flow.The stable operation of the energy storage inverter requires a reasonable control strategy,so the control strategy of the energy storage inverter has important research significance.This article first introduces the research background and significance of microgrid energy storage inverters,and expounds the research status and future development direction of energy storage inverters.Then the principle of bidirectional energy flow of the energy storage inverter is introduced,the main circuit topology of the energy storage inverter is analyzed,and the mathematical model of the energy storage inverter is established in the three-phase stationary coordinate system and the two-phase stationary coordinate system.And analyzed the principle of SPWM and SVPWM control technology.Based on the overall scheme of the energy storage inverter,the hardware of the energy storage inverter is designed.First design the high-frequency transformer and switching tube of the bi-directional DC-DC converter,then design the control chip and power supply of the energy storage inverter control circuit,and the power switching tube,LC filter circuit and driving circuit in the power circuit Design,and finally design the voltage and current sampling circuit.Aiming at the working state of the energy storage inverter in both energy storage mode and inverter mode,a voltage and current double closed-loop control strategy control strategy for the bi-directional DC-DC converter under the two states is proposed,and the MATLAB / SIMULINK simulation software Build a simulation model and verify thecontrol strategy.Then,a voltage and current double closed loop control strategy for the main controller of the energy storage inverter under two working states is proposed,and a simulation model is established under MATLAB / SIMULINK simulation software to verify the effectiveness of the control strategy.Aiming at the steady-state error in the operation of the energy storage inverter system,a control strategy for energy storage inverters based on repetitive control was proposed.The stability and convergence index of the repetitive controller were analyzed respectively.Finally,the simulation software MATLAB / SIMULINK verified the effectiveness of the control strategy.Aiming at the problem that the microgrid economic dispatch is complicated due to the addition of the microgrid to the energy storage system,a microgrid power economic allocation strategy based on a consensus algorithm is proposed.The microgrid distributed power is derived by analyzing the economic dispatch strategy and the consistency algorithm The power allocation strategy under the minimized cost was verified by the simulation software MATLAB / SIMULINK.