Design And Implementation Of AC Photovoltaic Water Pump System

In the current social development pattern of macro control,the world still faces many potential crisis of survival,such as fossil energy shortage,environment pollution situation is increasingly serious,people have to pay close attention to the future to solve the problem of energy.Therefore,the introduction and application of new energy has brought the gospel of the new era for mankind.Among them,the rational use of solar energy has become more worthy of attention.As an important application of the new energy industry,the photovoltaic water pump system has its own remarkable characteristics,such as zero pollution,high reliability and so on.In areas with abundant sunshine and rich underground water resources,it is more necessary to adopt and promote it.In general,the research of photovoltaic water pump system came into being,and it is of great significance in today's society.To put it simply,the working mechanism of photovoltaic pump system is essentially the integrated operation mechanism that interconnects and integrates various disciplines such as optics,machine,electricity and control technology.This paper focuses on the following aspects: the composition of photovoltaic pump system,the selection of machine and pump system,the characteristics of solar photovoltaic array,the maximum power point tracking control strategy and the control strategy of the system.Based on the research situation of photovoltaic pump system at home and abroad,this paper has a deep understanding of its application and technology status,and puts forward an overall control strategy and operation structure suitable for AC photovoltaic pump system,and enables it to run efficiently.Also part of the solar photovoltaic pump system,was analyzed its working principle,and to establish a mathematical simulation model.In addition,in the meantime,in order to maximize the output of the photovoltaic array using solar energy,the characteristics of the AC inverter process system taken into account is relatively complex,PV array voltage range is larger,the motor speed control system is convenient to realize the simple idea of using DC bus voltage space vector pulse width modulation high rate(Space Vector Pulse Width Modulation,SVPWM)variable frequency modulation algorithm(Varuabke Viktage Varuabke Frequency,VVVF)control technology.Aiming at the problem of Maximum Power Point Trackig(MPPT)of photovoltaic array,a new control algorithm called improved variable step perturbation and observation method is proposed through a series of theoretical analysis and comparison of different conventional algorithms.Both in the simulation environment of Matlab/Simulink or under the overall test platform,this new algorithm can show better performance performance.Meanwhile,according to the control strategy implemented by the AC photovoltaic water pump system,the corresponding hardware circuit and software design of DC/DC boost converter and DC/AC inverter are made respectively,and the corresponding local hardware simulation results are obtained.Finally,by using the experimental platform and simulation model,the simulation experiment and the simulation results of the designed system can be seen in the selection of the PV array size and can make the system reliable operation and achieve the maximum power point,and the inverter in the system can output three phase sine wave(the load motor adopts star connection),the voltage is 220 V and the waveform is stable,that is,it can satisfy the running conditions of three-phase asynchronous motor,and then drive the pump to carry water lifting operation in application.The whole experiment shows that the design of the system can achieve the expected work goal and run steadily.