Photovoltaic grid-connected inverter test bench

Abstract

The invention belongs to the technical field for testing photovoltaic grid-connected inverters, in particular to a test bench for testing various performance indexes of a photovoltaic grid-connected inverter. The test bench uses a photovoltaic battery array simulating power supply as the input source of the inverter so to displace the original real photovoltaic battery array, and uses a grid characteristic stimulating power supply to displace a large-power resistor load. The photovoltaic battery array simulating power supply can set the needed weather conditions like illumination, environment temperature, wind speed and the like conveniently, output a V-I (voltage-current) curve conforming to the requirements, and overcome the shortages that the real photovoltaic battery array has multiple uncontrollable factors and the installation and maintenance are not convenient. The grid characteristic stimulating power supply can simulate the characteristics like a grid voltage, a frequency, background harmonic waves and the like, can detect the working performances of the inverter under different grid states, and can feed back the output electric energy of the inverter to a public grid, so that the electric energy loss is reduced.

Description

technical field [0001] The invention belongs to the technical field of testing photovoltaic grid-connected inverters, and in particular relates to a testing platform for photovoltaic grid-connected inverters. Background technique [0002] Today, with energy depletion and environmental pollution becoming more and more serious, photovoltaic power generation technology has become a new energy technology that countries all over the world are vying to develop. The photovoltaic grid-connected inverter is the core component of the photovoltaic power generation system, and its performance is related to the utilization rate, reliability and power supply quality of the photovoltaic system. Therefore, it is necessary to have a comprehensive test platform that can detect various performance indicators of grid-connected inverters and ensure that the performance of the inverters meets relevant standards. [0003] However, when testing the inverter at present, the input source of the inve...

AI Technical Summary

Problems solved by technology

[0003] However, when testing the inverter at present, the input source of the inverter usually uses a real photovoltaic cell array or a DC analog power supply, which will bring various uncontrollable factors such as light conditions, ambient temperature, and wind speed. The cost of photovoltaic array is high, and the installation and maintenance are very inconvenient. The load on the output side of the inverter is usually composed of a high-power resistor and an AC voltage stabilizer. The working performance in the waveform state, but the device is a voltage source. In terms of circuit structure and design framework, it is impossible to realize the working state of bidirectional four-quadrant current source and voltage source in one device at the same time, and the output power of the inverter cannot be reversed. It is sent to the power grid, but directly consumed through resistance, which on the one hand causes a lot of waste of electric energy, and on the other hand, it is impossible to detect the performance of the four-quadrant working state of current / voltage between the photovoltaic grid-connected inverter and the grid

Images