Air conditioner

Abstract

The invention discloses an air conditioner which comprises a control module, a variable-frequency load and a power supply circuit; the power supply circuit comprises an alternating current module, a direct current boost module and a sampling circuit; the direct-current boosting module is connected with the alternating-current module and the control module respectively; the sampling circuit comprises an alternating current voltage sampling circuit and a direct current voltage sampling circuit which are respectively connected with the alternating current module, the direct current boosting module and the control module and are used for detecting sampled alternating current voltage and sampled direct current bus voltage and transmitting the sampled alternating current voltage and the sampled direct current bus voltage to the control module; the control module calculates an AC voltage peak value, a DC bus voltage and a difference between the AC voltage peak value and the DC bus voltage according to the sampled AC voltage and the sampled DC bus voltage, and records the difference as a peak voltage difference; the control module is configured with a peak pressure difference range and compares the peak pressure difference with the peak pressure difference range; when the peak voltage difference is within the peak voltage difference range, the sampling circuit is judged to be normal; and otherwise, it is judged that the sampling circuit is abnormal. Reliability and safety of operation of the air conditioner are improved.

Description

technical field [0001] The invention relates to the technical field of air conditioning, in particular to an air conditioner. Background technique [0002] The inverter air conditioner adopts the PFC (Power Factor Correction, power factor correction) circuit to perform power factor correction on the AC-DC link. After using PFC, the harmonic content injected by the inverter air conditioner into the power grid can be limited to the lowest level, and the power factor (ratio of active power to apparent power) is close to 1, so as to reduce the harmonic interference of the air conditioner electronic control to the external power grid. [0003] In a general PFC boost circuit, when the sampling resistor of the DC bus voltage detection circuit is badly welded, damaged or drifted and the value of the sampled DC voltage detected is still between the under-voltage protection value and the over-voltage protection value, it is not The PFC is activated as a fault. Since the detected DC ...

AI Technical Summary

Problems solved by technology

[0004] In order to solve the problem of PFC overvoltage or undervoltage caused by the abnormal sampling resistance of the DC bus voltage detection circuit in the prior art, the present invention provides an air conditioner that samples the AC voltage and the DC bus voltage and performs sampling according to the sampling value and setting Value to judge whether the sampling circuit is abnormal, and then solve the problem of overvoltage or undervoltage of the PFC circuit caused by abnormal sampling resistance, and improve the safety and reliability of the air conditioner operation

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