Abstract:Input-series output-parallel(ISOP) inverter which consists of low power modules connected in series at input and in parallel at the output, is suitable for the high input voltage and high power conditions. This paper proposes a centralized voltage sharing control strategy to obtain input voltage sharing and output current sharing. In the strategy, input voltage sharing regulator and output voltage regulator are integrated together, and provides control signals are provided to modules. Each module has its own current regulator and main circuit. Input voltage control loop makes high input voltage module with high output current, and low input voltage module with low output current, until input voltage sharing is achieved. When input voltages of modules are equal, all the modules have same reference of current loop, output current sharing is also achieved. This paper analyzes the control strategy, and proposes the design method of the control system by the decoupling theory. Finally, some experimental results are given to verify it.
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