Surge protection equipment and method

Abstract

The present invention provides a surge protection device and method, the device comprising: an acquisition circuit and a control circuit; wherein the acquisition circuit and the control circuit are respectively connected to the protected circuit; the acquisition circuit is used for real-time acquisition of the first current value of the protected circuit , and send the first current value to the control circuit; the control circuit is used to receive the first current value sent by the acquisition circuit in real time, and when it is determined that the first current value of the protected circuit is greater than the first current threshold, send the The circuit sends the first PWM control signal to close the PFC, and records the duration of the first current value greater than the first current threshold, and obtains the second current value of the compressor of the frequency conversion equipment in real time, and determines that the second current value is less than or equal to When the second current threshold is reached, it is judged whether the duration is less than or equal to the preset time, and when the duration is less than or equal to the preset time, a second PWM control signal is sent to the protected circuit to turn on the PFC. This scheme can improve the surge test level of the frequency conversion equipment.

Description

technical field [0001] The invention relates to the technical field of electronic engineering, in particular to surge protection equipment and methods. Background technique [0002] With the popularization of frequency conversion equipment, frequency conversion equipment produces large harmonics due to its high power. Therefore, active power factor correction circuits have emerged as the times require, and have become the mainstream solution adopted by frequency conversion equipment manufacturers to suppress harmonic interference. When using the active power factor correction circuit, due to the characteristics of the air conditioner itself, which has the characteristics of harsh use environment, wide operating power and large load fluctuation, how to ensure the reliability of the active power factor correction circuit has become a research focus. Among the protection functions, overcurrent protection is one of the important contents. [0003] The Chinese patent application...

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Problems solved by technology

[0004] However, when the surge test is performed, the PFC circuit in the prior art will stop the whole inverter device when performing over-current protection, thus reducing the surge test level of the inverter device.

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