Photovoltaic inverter DC component failure

What causes a two-stage PV inverter to fail?

Since the two-stage PV inverter has an intermediate DC/DC link, there is a certain voltage difference between the PV module and DC capacitor, and the fault coupling degree of undervoltage is lower than that of overvoltage fault. According to the fault location, the fault causes can be divided into two types: DC short circuit and sampling error.

Why do PV inverters fail?

Some authors discuss inverter failures due to the issues of reactive power control. The PV inverters operate at unity power factor, but as per the new grid requirements, the PV inverters must operate at non unity power factor by absorbing or supplying reactive power to control the grid voltage and frequency.

What causes coupling in DC side of photovoltaic inverter?

There are multiple fault causes coupling in DC side of photovoltaic inverter. The changes of voltage, current and power are derived by fault mechanism analysis. The differences of failure feature are used to locate the fault cause. 1. Introduction

Does central inverter failure affect PV power plant availability & Roi?

This paper reviewed several publications which studied the failures of the PV power plant equipment’s and presented that the central inverter failures rate is the highest for the PV power plant equipment’s which affected negatively in both PV power plant availability and ROI.

What is DC overvoltage fault in inverter?

2.2. DC overvoltage fault The condition of DC overvoltage fault in inverter is that the DC capacitor voltage exceeds maximum allowable voltage Umax and maintains for a period of time, which triggers overvoltage protection and causes the inverter to stop.

What is failure causes analysis of grid-connected inverters?

The central inverter is considered the most important core equipment in the Mega-scale PV power plant which suffers from several partial and total failures. This paper introduces a new methodology for Failure Causes Analysis (FCA) of grid-connected inverters based on the Faults Signatures Analysis (FSA).