200 W low cost module integrated utility interface for modular photovoltaic energy systems

This paper describes the design of a utility interface for a 200 W solar cell array. The interface comprises high frequency soft switching PWM power conversion, analog and logic control and protection circuits and an analog maximum power point tracker (MPPT). All circuits are implemented with standard components (no microcontroller) and thus facilitates integration into ASIC components at a later development stage. The design emphasis is on module integration, low cost production and compliance with standards on utility interfacing. The special requirements of utility interfacing and solar cell array utilization are described and the design of the components of the utility interface is described. The theory and design are verified with the implemented laboratory prototype, which shows excellent performance and verifies the operation of the interface.