Three-phase power supply conversion circuit, overcurrent protection method, circuit board and air conditioner

Abstract

The invention discloses a three-phase power supply conversion circuit, an overcurrent protection method, a circuit board and an air conditioner, the three-phase power supply conversion circuit comprises a rectifier module, a current detection module and a controller, the rectifier module comprises a three-phase rectifier bridge and a bidirectional switch assembly, the three-phase rectifier bridge comprises three bridge arms which are connected in parallel, and the bidirectional switch assembly is connected with the three bridge arms. The bidirectional switch assembly comprises three groups of bidirectional switches, each group of bidirectional switches is connected with the midpoint of each bridge arm in a one-to-one correspondence manner, the controller is connected with the current detection module and the bidirectional switch assembly, and the controller is used for receiving a line current value detected by the current detection module and controlling the working state of the bidirectional switch assembly according to an overcurrent protection strategy; according to the embodiment of the invention, the bidirectional switch is directly controlled through the controller, and no extra circuit component is needed to drive the bidirectional switch, so that the use of the circuit component is reduced, the circuit design difficulty is reduced, the probability of false triggering of overcurrent protection is reduced, and the load can continuously and stably operate.

Description

technical field [0001] The invention relates to the field of electronic circuits, in particular to a three-phase power conversion circuit, an overcurrent protection method, a circuit board and an air conditioner. Background technique [0002] At present, inverter air conditioners use three-phase power supply rectification and power supply, and pulse width modulation technology is usually used for power supply control. Since each phase voltage input corresponds to a current, any phase current that is too large will cause damage to the air conditioner. Under the existing technology, in order to shut down the work of the rectifier module when the current is too large, multiple comparators, latches and other circuit components are used to form the control circuit. On the one hand, the design cost and material cost are increased. On the other hand, the newly added The control circuit easily triggers the overcurrent protection by mistake when the air conditioner operates at high f...

AI Technical Summary

Problems solved by technology

[0002] At present, inverter air conditioners use three-phase power supply rectification and power supply, and pulse width modulation technology is usually used for power supply control. Since each phase voltage input corresponds to current generation, excessive current in any one phase will cause damage to the air conditioner.

Under the existing technology, in order to shut down the work of the rectifier module when the current is too large, multiple comparators, latches and other circuit components are used to form the control circuit. On the one hand, the design cost and material cost are increased. On the other hand, the newly added The control circuit is easy to accidentally trigger the overcurrent protection when the air conditioner is running at high frequency or external noise interference, causing frequent shutdowns of the air conditioner. Therefore, the current overcurrent protection method of the three-phase power rectifier power supply is not effective

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