Active Power Decoupling Control for Single-Phase Current Source Rectifier Based on Emulating LC Resonator

The ripple power with double grid frequency inherently exists in a single-phase current source rectifier. To achieve the constant dc-link current, an alternative way is to use an LC resonator tuned at 100 Hz to block the ripple power. However, this method requires large passive components, which will degrade the power density and even the reliability. What is worse, the decoupling performance will be deteriorated when the parameter drifts happen. In this letter, a control strategy based on emulating the output voltage characteristic of the LC resonator is proposed. Then, the decoupling function as the same with using a real LC resonator is achieved. At the same time, no bulky passive components are needed and the issue caused by parameter drifts is also avoided. In addition, the modular design of the LC emulator can be achieved. A prototype was built to verify the effectiveness of the proposed method.