Development of PQ capability chart for grid-connected PV system

Abstract

This report provides brief summary of two-semester Final Year Project (FYP) with School of Electrical & Electronics Engineering. The objective of this FYP is to develop a

detailed model using MATLAB/Simulink software which can produce optimum P corresponding to irradiance data. The model can be able to plot active power set point versus irradiance chart. The chart allows the student to study and analyze voltage, current and power transitions at varying irradiation of Photovoltaic (PV) plant.

The project was firstly focused on developing detailed model using MATLAB/Simulink environment. In detailed model design, irradiance data was injected into PV plant and power output from PV plant would pass through a power condition system (DC-DC-AC converter) before being supplied into the grid. Maximum power point tracker (MPPT) was integrated with DC-DC boost converter to extract maximum power point at specific

irradiance level. Detailed model was successfully designed and tested by using 1kW PV plant specification and simulated irradiance data. Simulink detailed model was also verified with real-time collected data from PV plant (1kW and 2.7kW) by setting real-time irradiance data as an input into detailed model. To obtain real-time data, NI LABVIEW based program was implemented to log real-time data with 1 min interval and develop P/Q capability chart for 1kW and 2.7kW PV plant.

The software enables fast and reliable measurement function including data acquisition, measurement results presentation (Visualization on the screen and generation of report).

From that logged data, Simulink detailed model was successfully verified by comparing real-time logged active power and Simulink output active power. Error percentage was

3.93% for 2.7kW PV plant and 2.62% for 1kW PV plant respectively.

By developing detailed model, it is possible to completely characterize a PV plant in terms of P injection into grid. This P capability chart helps the calculation of units of energy produced.