Voltage-limiting circuit system of mining switching power supply with increased input voltage range

Abstract

The invention provides a voltage limiting circuit system of a mine switching power supply for expanding an input voltage range. The voltage limiting circuit system comprises a voltage limiting processing circuit, a feedback circuit, an output circuit and a power supply circuit. The output circuit has an input end connected with the output end of the pre-stage processing circuit of the mine switching power supply, and an output end connected with one end of the primary winding of a flyback transformer of a flyback converter circuit of the mine switching power supply. The input end of the feedback circuit is connected to the input end of the output circuit and the output end of the feedback circuit is connected to the feedback signal input end of the voltage limiting processing circuit. Thefeedback circuit is used for detecting the voltage value of the DC power output by the pre-stage processing circuit and inputting a voltage detection signal to the voltage limiting processing circuit.The voltage limiting processing circuit has a control end connected with the output circuit and is used to limit the voltage when the DC power is higher than the rated voltage of the flyback converter circuit. The power supply circuit is used to provide working power for the voltage limiting processing circuit. The voltage input range of the mine switching power supply is effectively expanded.

Description

technical field [0001] The invention relates to a switching power supply circuit, in particular to a voltage-limiting circuit system of a mining switching power supply that increases the input voltage range. Background technique [0002] The switching power supply is the most important equipment in mining equipment. The switching power supply for mining is generally composed of two parts, one is the pre-processing circuit, which is used to rectify and filter the input AC power, and also perform anti-surge protection. The DC output from the pre-processing circuit is input to the flyback conversion circuit for voltage stabilization and conversion, and then provided to the load equipment. However, the input range of the existing mining switching power supply has certain limitations, that is: each mining switch The power supply has a rated input voltage range. When it exceeds this voltage range, the switching power supply cannot be used and must be replaced with a power supply o...

AI Technical Summary

Problems solved by technology

[0002] The switching power supply is the most important equipment in mining equipment. The switching power supply for mining generally consists of two parts, one part is the pre-processing circuit, which is used to rectify and filter the input AC power, and also perform anti-surge protection. The DC output from the pre-processing circuit is input to the flyback conversion circuit for voltage stabilization and conversion processing, and then provided to the load equipment. However, the input range of the existing mining switching power supply has certain limitations, that is: each mining switch The power supply has a rated input voltage range. When it exceeds this voltage range, the switching power supply cannot be used and must be replaced with other grades of power supply. Therefore, using the existing switching power supply in mines will increase the cost of use and adapt to Moreover, the existing underground coal mine input power supply voltage includes four input voltage levels of 127VAC / 220VAC / 380VAC / 660VAC. When the highest 660VAC AC input is exceeded, the existing mining switching power supply cannot be used. Using other equipment for decompression treatment will further increase the cost of use, and it is inconvenient to use

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