DC (direct-current) converter voltage-sharing technology with multiple modules having series inputs and parallel outputs

With the fast development of power electronic technologies, the development of power electronic system integration techniques becomes a tendency. In application situations of high-voltage input and large-current output, a DC (direct-current) converter system with multiple modules having series inputs and parallel outputs can be used widely. The key problem of the DC (direct-current) converter system with multiple modules having series inputs and parallel outputs is to ensure voltage sharing of input ends of all modules in the system. For the purpose of realizing the voltage sharing, a voltage loop, a current loop and a voltage-sharing ring are traditionally used to control, each module is required to input voltage detection signals, the circuit is complicated and the control difficulty is high. The invention provides a voltage-sharing technology among modules at input ends, thus realizing the voltage sharing of the multiple modules at the input ends. The control characteristics are as follows: a voltage-current dual-loop control method is adopted, voltage sampling is output voltage sampling, current sampling is the total current sampling of the current output of each module, and each module is controlled by the same duty ratio, thus realizing the voltage sharing at the input ends. The circuit is controlled simply and certain redundancy is provided.