Design and Evaluation of a–120Watt DC – DC Amplifier for Solar Cell Module Applications

Abstract – The design, implementation and evaluation of 120Watt dc – dc amplifier for solar cell module applications are presented. The aim of this study is to amplify a low output dc voltage from a 80-Watt, 12V solar cell module, and use the operation principle of chopper amplifier to achieve a high dc voltage that is enough to charge two - 12V, 60AH batteries. A 16 pin dual-in-line SG3524 IC is employed in the design of the system which comprises of astable square wave oscillator that converts the output dc of photovoltaic module to square wave ac, and a class B push – pull employing IRFP 250 MOSFET power driver to amplifier the output of the oscillator and use it to drive the power transformer in the system. With the help of bridge rectifier, RC filter, and switching regulator, a stabilized dc output is obtained to charge the required battery size. Design calculations were done with the aid of MATLAB R2007a software. The results of practical laboratory test carried out show that the oscillator and power amplifier output voltages of 4.5V and 26.0V were achieved respectively. The efficiency of the oscillator stage is ~51.6% in agreement with the calculated design efficiency. Also, the measured efficiency of the amplifier is ~50.0%. The measured output power is ~120.0Watt.