Photovoltaic direct current power generation system with energy storage equipment and control method thereof

Abstract

The invention discloses a photovoltaic direct current power generation system with energy storage equipment and a control method thereof. The photovoltaic direct current power generation system with the energy storage equipment comprises three photovoltaic arrays, three BOOST converters, two pieces of energy storage equipment, two bi-directional DC / DC converters, a resistive load and a constant power load. According to the control method provided by the invention aiming at the system, two working modes, namely, an MPPT control mode and a constant voltage output mode, are set for the BOOST converters; three working modes, namely, a BUCK mode, a BOOST mode and a cutting-off mode, are set for the bi-directional DC / DC converters; the working modes of the BOOST converters and the bi-directionalDC / DC converters are reasonably switched by a controller according to the working state of the system; the integration of the photovoltaic arrays and the energy storage equipment is realized, so thatthe stability of a direct current bus is ensured, and meanwhile, the solar energy received by the photovoltaic arrays is utilized at maximum efficiency; and the controller can make fast adjustment toensure the stability of the voltage of the direct current bus under special conditions that the light intensity is weakened, a load changes suddenly and the like.

Description

technical field [0001] The invention belongs to the field of DC micro-grid control of power systems, relates to a control algorithm for automatic control of photovoltaic energy storage systems, and specifically designs a control algorithm based on MPPT control, voltage closed-loop control, current tracking control, and current compensation control And a photovoltaic energy storage system controlled by the control algorithm. Background technique [0002] A solar power system that is not connected to the grid is called an off-grid photovoltaic power system. The energy of this photovoltaic power generation system comes only from the solar cell array. At night or when there is insufficient light, the solar array will not be able to provide enough energy for the load. Therefore, in order to ensure the reliability and stability of the off-grid photovoltaic power generation system, the system must be equipped with energy storage equipment to store and regulate electric energy. W...

AI Technical Summary

Problems solved by technology

The principle of master-slave control is to set the equipment that directly participates in the DC bus voltage regulation as the master control unit, and the rest as slave control units; the peer-to-peer control method makes each part have the same role, and only needs to adjust itself through feedback, avoiding the need for master control. The control unit communicates with the Internet, but the peer-to-peer operation mode in the independent state reduces the robustness of the system and weakens the overall anti-interference ability

Images