Improved 2 kW solar inverter with wide input voltage range

In case of medium voltage (several tenth up to several hundred volts) solar inverter applications a DC-to-DC converter for voltage level adaptation is required. To rise the overall efficiency of the inverter a synchronized multiphase PWM concept was chosen. Both, the DC-to-DC converter and the mains coupled DC-to-AC inverter can be realized as multiphase stages. In our case only the DC-to-DC converter is realized as a multiphase system. In this paper a 120 V-240 V DC(input) to 230 V AC(output)/2 kW converter is derived. In the current paper the development of the inverter is described, realization hints are given and the efficiency of the complete inverter is compared to a conventional solution.