Design Of Household Pv Inverter Based On Electric Energy Router

In order to reduce the impact of a large number of household PV inverters connected to the grid and improve the use of photovoltaic power generation for household use “self-use”,and in order to facilitate the future to be able to do distributed generation and energy management of household loads as background.This paper studies the design of household photovoltaic inverters based on energy routers.Energy routers have the advantage of "local consumption." The energy router can make the photovoltaic power generation and the load as a whole conducive to energy management and reduce the impact of traditional photovoltaic power generation on the power grid.The most important part is inverters in new energy generation.Photovoltaic inverters are the converter devices specific to electrical energy conversion.Photovoltaic inverters are important devices for realizing photovoltaic power generation.This paper focuses on energy conversion and stored.This article first analyzes the structure of the household energy router.According to the structure of the household energy router,the battery is selected to realize bidirectional flow of the battery and the DC bus through the BUCK-BOOST circuit.The topology of the inverter selects a single-phase full-bridge inverter circuit.The control strategies of the battery when working in BUCK mode and BOOST mode were separately studied and verified by simulation.For the large number of traditional household PV inverters distributed at the ends of the grid,most of them do not have the function of dynamic reactive power compensation,and one of the functions of the energy router is reactive power compensation.This paper studies the control strategies of dual-function household PV inverters that implement power generation with unit power factor and dynamic reactive power compensation.The second-order generalized integrator is used to reconstruct two-phase quadrature vector and the load current is detected through instantaneous reactive power theory to obtain the required reactive current component.From the active power component of the power control link to the grid,the reactive current component on the load and the active current component obtained from the power control component are combined to obtain the reference current of the current inner loop.The current inner loop uses a PI and repeat control strategy in parallel to ensure steady-state performance while using PI control to enhance system dynamic performance.The Simulink simulation verifies the dual functions of the household PV inverter,which can generate dynamic power and reactive power compensation at the same time with unit power factor.In order to improve the "spontaneous use" rate,according to the structure of the energy router,adding an interface of controlling the heat storage load.When the photovoltaic output is greater than the general load demand,energy can be stored through the heat storage load.Finally,the above analysis is verified by simulation software.Finally,a 3kW photovoltaic inverter experimental platform was designed,and the specific parameter calculation and device selection were given.Software protection and hardware protection circuits,voltage and current sampling conditioning circuits,and zero-cross comparison circuits were designed.And gives the software flow chart of the system work.