AC power

Inverter

Electrical engineering

Engineering

Control engineering

Analog signal

Artificial intelligence

Voltage

Topology (electrical circuits)

Harmonics

Common-mode signal

Decoupling (probability)

Electronic engineering

Control (management)

Ripple

Grid-tie inverter

Maximum power point tracking

Computer science

Photovoltaic system

Control theory (sociology)

Capacitor

Digital signal processing

IEEE Transactions on Industrial Electronics

To solve the problems of existing nonisolated PV grid-connected inverters, such as leakage current, power pulsation, and harmonic current, a single-phase common-ground-type nonisolated grid-connected inverter with power decoupling capability is proposed in this article. The integration of the traditional boost converter and the switched capacitor technology obtains the structure that the neutral point of the grid is directly connected with the negative terminal of PV array, and the leakage current is eliminated. Due to the time-sharing multiplexing of circuit components, which can achieve power decoupling and high step-up, fewer semiconductor devices are required in proposed inverter. At the same time, the improved control strategy ensures that the inverter can adapt to the voltage ripple of large decoupling capacitor. This article introduces the working principle, mode, performance, and control strategy of the novel topology in detail. Finally, the experimental prototype with rated output power of 320W verifies the superior performance of the inverter.

A Single-Phase Transformerless Common-Ground Type PV Inverter With Active Power Decoupling