Development of grid-tie home electricity supply system (GHESS) using solar energy

• Main Author: See, Kok Leng.
• Other Authors: Wang Peng
• Format: Theses and Dissertations
• Language: English
• Published: 2014
• Subjects: DRNTU::Engineering::Electrical and electronic engineering
• Online Access: http://hdl.handle.net/10356/55304
• Institution: Nanyang Technological University

The title of this dissertation is Development of Grid-Tie Home Electricity Supply System (GHESS) Using Solar Energy. This report covers the concept, design and implementation details of a GRESS using solar photovoltaic energy as the main source of energy. A simulation model was constructed and simulated using the Matlab® Simulink software and a functional prototype was physically built and tested. The system performance data of the functional prototype was collected for analysis and verification with the design and simulated data. The GRESS comprises mainly the DC-DC boost converters, Sine Wave PWM Inverters, high frequency power line filters and a power electronic controller system. Literature review on DC-DC converters, Sine wave PWM inverters, filter and grid inverter technologies provides a basic building block in the system design concept. Performance of the DC-DC boost converter and Sine wave PWM inverter prototypes were tested individually and verified with the simulated data before integrated as a total system. The main component of the control system is a enhanced flash 8-bit microcontroller from Miocrochip. The model selected is PIC18F4431 clocking at 40MHz. It has 8 channels of 14-bit complementary output power control PWM modules and 9 channels of 10-bit AID inputs which are sufficient and suitable for this application, controlling both the DC-DC converter and the inverter concurrently and independently. Familiarization of the Microchip MPLAB embedded "C" programming environment is essential for developing the source code program for the microcontroller. A Matlab software algorithm is written to generate 20kHz PWM pulse sequence tables for different modulation indexes. For human user interface, a 40 columns by 4 rows characters LCD display is programmed to display the system status and conditions. For system stability and control, a digital PID controller with anti-windup protection is implemented to improve the response of the DC-DC boost converter. Literature review for various MPPT algorithms was done and the Perturb and Observation method is implemented due to is simplicity in programming.