Design and Implementation of 1.5 kW Solar Pumping System

Abstract

Solar Water Pumping System (SWPS) is increasingly popular in remote areas where grid is not available or unreliable. This system is mainly used for irrigation purpose in farming and household purpose. Ministry of New and Renewable Energy(MNRE) gives subsidy on this product, hence product is designed to satisfy the requirement of MNRE. As per MNRE norms either DC motor or AC motor is used. In this topology induction motor along with submersible pump is used. In this project 1.5 kW induction motor is used. On the basis of motor rating solar panel rating is decided to be 1.8 kW considering losses in the system. In this project the main focus is to design boost converter which boosts the voltage obtained from solar panel whose power rating is1.8 kW. This boost voltage acts as a DC-link voltage for 3-‑ Ø inverter. 3-‑ Ø inverter is developed which converts DC voltage to AC voltage. This AC voltage generated is given to induction motor which runs the submersible pump. Maximum Power Point Tracking (MPPT) algorithm is implemented to obtain maximum power from the solar panel under different solar irradiation and temperature. In this topology incremental conductance method is used to obtain maximum power from solar panel. Modulation index of inverter is controlled by sine-triangle Pulse Width Modulation (PWM) technique. PWM along with V/F method is implemented for the control of inverter which results in the control of speed of induction motor when the output from solar panel changes. Design and simulation verification of the system is performed in PSIM software. After satisfactory results are obtained in simulation,hardware is carried out. Hardware setup is tested on resistive load. Once the required output is obtained on resistive load, hardware setup is tested on motor-pump set. Hence with obtained output necessary corrections are made to enhance the performance of the product. This topology can be synchronized with the AC drive to use the grid supply when solar energy is not available.