Current detecting circuit for overload protection and overcurrent protection of brushless direct current motor
A technology of current detection circuit and brushed DC motor, which is applied in the direction of measurement using digital measurement technology, can solve the problems of affecting control accuracy, saturation of transformer magnetic core, poor accuracy, etc., and achieve simple circuit structure and current detection accuracy High and low cost effect
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Publication Date
- 2014-02-05
- Estimated Expiration
- Not applicable · inactive patent
Smart Images
Figure 1 Figure 2 Figure 3
Abstract
Description
technical field
[0001] The invention relates to a current detection circuit for overload protection and overcurrent protection of a brushless direct current motor. Background technique
[0002] In the electric actuator, the torque limiting mechanism is used to cut off the motor control circuit when the load torque is too large, so that the motor stops until the fault is eliminated, so as to avoid overload, so as to ensure the integrity of the physical structure of the motor and the safety of the operator. The electronic torque detection method can obtain a more accurate torque value through calculation, so in some occasions it has replaced the mechanical torque limiting mechanism that can only qualitatively reflect the magnitude of the torque, and has become a common method for torque detection.
[0003] According to the basic theory of the motor, its torque value can be obtained by calculating the motor current, speed, etc., and the speed is relatively easy to observe. Ther...
Examples
Embodiment Construction
[0011] Such as figure 1 , 2 , 3, the current detection circuit for brushless DC motor overload protection and overcurrent protection, including single-chip microcomputer, current sampling circuit and power module, the current sampling circuit is connected with the single-chip microcomputer and power module respectively; the specific circuit connection is: current sampling In the circuit, pin 1 of the operational amplifier chip U9 is connected to pin 22 of the microcontroller and one end of resistor R48, pin 2 is connected to one end of resistor R55 and the other end of resistor R48, pin 3 is connected to resistor R50 and one end of capacitor C48 , The 6-pin connection of the operational amplifier chip U9, the 5-pin connection with one end of the resistor R56 and the resistor R49, the 7-pin connection with the 9-pin connection of the single-chip microcomputer U10, the 4-pin connection with the public ground GND, and the 8-pin connection with the chip power supply VCC; The 22 p...