Improving Low Voltage Ride Through Capabilities of Grid Connected Residential Solar PV System Using Reactive Power Injection Strategies

摘要

The ever increasing demand of electricity has allowed the application of renewable energy sources in the traditional transmission and distribution networks. However current power system network is designed for the conventional energy sources. Hence, they are vulnerable to the newly injected renewable sources of electricity. The problem lies in the inherent operating constraints of renewable sources. The output of renewable energy sources like solar and wind cannot be accurately predicted. This has given birth to the power system stability and security issues. Even though PV inverters are being used in the low voltage grid at larger scale, they do not support grid during faults. Such first generation PV inverters should be embedded with basic LVRT (Low Voltage Ride Through) capabilities like improving voltage profile and disconnecting the system after predefined time. This paper introduces a MATLAB simulation of 3 phase grid tied inverter which synchronizes with grid during healthy condition and disconnects during faulty condition as per grid requirement. The aim of this simulation is an implementation of the LVRT logic and adding voltage profile improvement capability in 1st generation PV inverters. The focus is on implementing basic LVRT logic for the existing systems. Simulated results validate the basic LVRT ability.