Grid-connected photovoltaic alternating current voltage stabilizer using photovoltaic electricity for active energy supplementation

Abstract

The invention relates to a grid-connected photovoltaic alternating current voltage stabilizer using photovoltaic electricity for active energy supplementation. The grid-connected photovoltaic alternating current voltage stabilizer comprises a solar panel, a direct current conversion circuit, an input industrial frequency voltage transformer, an inverter circuit, an output industrial frequency isolation voltage transformer and an anti-thunder SPD, wherein two taps of the input industrial frequency voltage transformer and the output industrial frequency isolation voltage transformer are respectively connected with first and second tap shunt control switches; the control []signal input ends of the two tap shunt control switches are respectively connected onto an output port of a comparison control circuit; the input end of the comparison control circuit is connected at the output end of a voltage amplitude phase monitoring circuit; the input port of the voltage amplitude phase monitoringcircuit is connected onto the primary end of the output industrial frequency isolation voltage transformer; the anti-thunder SPD is connected in parallel onto a secondary electrode end of the output industrial frequency isolation voltage transformer. By automatically changing the input industrial frequency voltage or the output alternating current voltage, an electric network is charged at the ultralow electric network voltage; an inside circuit is used for realizing the electric complete isolation protection with the external electric network; the continuous work in a thunderstorm period is ensured.

Description

technical field [0001] The invention relates to a grid-connected photovoltaic AC voltage stabilizer, in particular to a photovoltaic AC voltage stabilizer that can normally follow the power grid to work under the condition of ultra-low grid voltage. Background technique [0002] Grid voltage fluctuation is a very normal power supply phenomenon. There are many reasons for grid voltage fluctuations. The obvious ones include changes in the power generation capacity of the power supply system and changes in the power load of the grid. (distribution transformer copper loss) and line loss (line copper loss). When the power generation capacity decreases, the load is too heavy, or the copper loss of the mains grid increases with the increase of the ambient temperature within a certain period of time, the grid voltage will be too low. At this time, some users at the back end of the grid cannot use it normally. Therefore, these users use the AC voltage stabilizer to increase the pow...

AI Technical Summary

Problems solved by technology

Generally, when the solar output power is at its maximum, the grid line loss is also at the maximum value. At this time, most of the power supply voltage of the end line at the low-voltage end of the grid exceeds the -15% requirement, but at this time the grid-connected photovoltaic inverter cannot work normally. Therefore, it loses the role of the best photovoltaic power supplement to stabilize the grid voltage

[0010] In addition, lightning strike is a natural disaster, and solar power generation is a large investment. Without reliable lightning protection technology and measures, it cannot play a good role in this investment.

Images