Research On Photovoltaic Water Pump Group Control System Based On Master-Slave Control

As an important application of photovoltaic power generation and an important extension of stand-alone photovoltaic water pump systems,photovoltaic water pump group control systems have broad application prospects because stand-alone photovoltaic water pump systems cannot match the water demand in various environments.This article mainly studies the characteristics and models of the main components of the photovoltaic water pump group control system,determines the topology of the system,establishes a mathematical model of the multi machine photovoltaic water pump,studies the vector control of the drive motor,and stabilizes the array voltage of the photovoltaic water pump group control system.The main contents include the following.This article studies various important components of the photovoltaic water pump group control system,including the mathematical model of the photovoltaic array,the mathematical model of the driving motor,and the performance characteristics of the water pump.The driving motor is a three-phase asynchronous motor.Based on the existing mathematical model of a single photovoltaic water pump and combined with the equivalent circuit of multiple photovoltaic water pumps,a mathematical model of multiple photovoltaic water pumps is obtained,providing support for the study of photovoltaic water pump group control strategies.Then,the shortcomings of traditional proportional control are analyzed,and the master-slave control is studied in detail.Under the control block diagram of the master-slave control system,the outer voltage loop,inner current loop and flux observation of the host are designed,and the Bode diagram of the open loop transfer function of the voltage loop and current loop is analyzed to verify that it can meet the requirements of system stability.The host vector control simulation and the multi-machine simulation under master-slave control were built in MATLAB/Simulink to verify the feasibility of the rotor flux orientation vector control strategy.In the multi-machine simulation under master-slave control,the photovoltaic water pump system can keep the array voltage stable.In addition,the maximum power point tracking strategy and the current sharing control strategy of the upper computer are designed.Finally,the photovoltaic water pump experimental platform was designed and built.The hardware design mainly includes the main circuit design of the frequency converter,the drive circuit design,the sampling protection circuit design,and the DSP controller circuit design.The system operation program was written based on the CCS7.4 software,and a simple upper computer communication human-machine page was built using Labview.The photovoltaic array is replaced by a programmable DC power supply.On the established photovoltaic water pump experimental platform,the photovoltaic water pump system under the speed sensorless vector control algorithm is tested,and the experimental data is analyzed to verify the feasibility of the master-slave control proposed in this article through experiments.