SPWM Carrier Synchronization Method Based on CAN Bus

Carrier synchronization is traditionally implemented in analog method in parallel operation of power modules. Carrier connection of modules is via wires paralleled with communication wires of modules. These signals may be mutual interfered and affected by power circuit. Therefore, reliability of parallel system is reduced. This paper developed a digital carrier synchronization method based on CAN bus, in which realizing digital communication per carrier period and carrier synchronization of parallel power electronics modules through only one pair of CAN bus. The experiment uses TMS320F2812 with CAN peripherals as control chip and designed two parallel inverters. The experiment verified that the proposed method is feasible and has good anti-interference ability.