An Implementation of Cable Resistance in Modified Droop Control Method for Parallel-connected DC-DC Boost Converters

For load current sharing between parallel-connected DC-DC boost converters, a modified droop method with varying cable resistance is presented in this paper. The droop method provides a suitable current sharing in the system because there is no intercommunication link between the parallel-connected modules. However, when the cable resistance is considered, a small mismatch in output voltage of parallel-connected converters leads to circulating current and unequal load current sharing between two modules. To resolve this issue without using a communication link between modules, the modified droop method based on cable resistance implementation is proposed to improve the load current sharing. This can be established by adjusting the output voltage for each converter of the parallel-connected converters individually and according to modified load regulation characteristic of the droop method. The effectiveness of the proposed method is demonstrated using Matlab/Simulink simulations.