PFC (Power Factor Correction) fault detection method for direct-current variable frequency air conditioner controller

Abstract

The invention discloses a PFC (Power Factor Correction) fault detection method for a direct-current variable frequency air conditioner controller, comprising the following steps of: (1) detecting an overvoltage value Up and an undervoltage value Ud of a direct-current bus voltage of a direct-current variable frequency controller, and detecting a direct-current voltage U by a direct-current bus voltage detection circuit arranged on the direct-current variable frequency controller; (2) when U is less than or equal to Ud or U is more than or equal to Up, immediately stopping a pressing machine, and reporting overvoltage and undervoltage protection faults; (3) detecting the maximum direct-current voltage Umax and the minimum direct-current voltage Umin when PFC is in normal regulation within the allowable voltage range; (4) when the direct-current bus voltage works within the range that U is more than or equal to Umin and is less than or equal to Umax, determining that PFC is in normal regulation and the pressing machine normally works without PFC faults; and (5) when U is more than or equal to Ud and is less than or equal to Umin or U is more than or equal to Umax or less than or equal to Up, reporting the PFC faults. With the PFC fault detection method, PFC regulation faults can be reported in time, therefore, the faults can be found as earlier as possible and maintained in advance, and the pressing machine can be prevented from burning so as to lower cost.

Description

technical field [0001] The invention relates to the technical field of DC frequency conversion air conditioner electric control, in particular to a PFC fault detection method for a DC frequency conversion air conditioner controller. Background technique [0002] Today's energy saving has become one of the hottest topics at present, and the state encourages energy saving. Therefore, the more energy-saving and comfortable DC inverter air conditioner instead of the fixed frequency air conditioner is the current and future development trend of the air conditioning industry. This is actually the case. Now the main air conditioners of major air conditioner manufacturers use DC inverter air conditioners. Inverter air conditioner controllers are relatively complex, and basically more than 80% of DC inverter air conditioners are controlled by PFC compensation. There are many types of PFC, but all PFC (power factor corrector) function is to adjust the PFC switch by detecting the DC ...

AI Technical Summary

Problems solved by technology

The PFC adjustment of DC inverter air conditioners on the market is only unidirectional, that is, when the PFC adjustment needs to be turned on, the control board circuit controls the PFC to work, but the main controller cannot detect whether the PFC control plays a regulating role, so If the PFC is abnormal, it cannot play a regulating role, and the user cannot know

In order to ensure that the controller works within a relatively large input voltage range, generally the compressor can operate with or without the PFC turned on, but when the PFC needs to be turned on, if the PFC does not actually work due to circuit problems or interference problems or other abnormal conditions Adjustment, at this time the compressor is running in a state where the voltage and current are unreasonable

When the compressor will run at unreasonable voltage or current for a long time, the service life of the compressor will be greatly shortened, which will greatly increase the maintenance cost