Motor Terminal Voltage Acquisition Circuit and Its Application

Abstract

The invention discloses a motor end voltage acquisition circuit. The motor end voltage acquisition circuit comprises a first first-order low-pass filtering module, a voltage division network module, asecond first-order low-pass filtering module, an isolation operational amplifier and the like, the input end of the first first-order low-pass filtering module is connected to the end portion of themotor and is used for filtering a first high-frequency component; the voltage division network module is used for carrying out voltage division on the signal output by the first first-order low-pass filtering module; the input end of the second first-order low-pass filtering module is connected to the output end of the voltage division network module and is used for filtering a second high-frequency component; the isolation operational amplifier is used for isolating input and output signals. Isolated acquisition of the end voltage is achieved by the aid of the isolation operational amplifier,the resistor, the capacitor and the like, acquisition of the end voltage of the motor can be achieved by the aid of fewer devices and lower resistor power consumption, hardware cost is reduced, the size of the circuit is reduced, strong and weak electricity isolation is achieved, and reliability of the circuit is improved beneficially.

Description

technical field [0001] The invention relates to a motor, in particular to a motor terminal voltage acquisition circuit, which belongs to the field of electronic technology. Background technique [0002] When the rim motor is running, it is necessary to detect the three-phase voltage at the end of the motor in real time for the calculation of the internal motor model of the controller. The three-phase end voltage of a conventional motor is generally detected by a voltage Hall sensor. However, the voltage Hall sensor is large in size, at least three are required in the application, and the cost is high, and the front end of the sampling resistor needs to select the resistor according to the input current of the Hall sampling, the resistor has high power consumption and serious heat generation, which will affect the reliability. . Contents of the invention [0003] The main purpose of the present invention is to provide a motor terminal voltage acquisition circuit, so as to ...

AI Technical Summary

Problems solved by technology

However, the voltage Hall sensor is large in size, at least three are required in the application, and the cost is high, and the front end of the sampling resistor needs to select the resistor according to the input current of the Hall sampling, the resistor has high power consumption and serious heat generation, which will affect the reliability.

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