Brushless motor vehicle maintenance tutorial
6 power MOSFET tube according to certain requirements in turn, can realize brushless motor A, B, C three-phase winding alternating power, complete commutation requirements, motor normal operation. In the electric vehicle brushless motor controller, the 6 power tubes 22 through use of electricity and 33 electric mode, 22 power that every moment there are two power tubes and electricity, 33 electricity that every moment there are three power tubes energized simultaneously. For the 22 way power, the power tube must press VT1, VT2, VT2, VT3, VT3, VT4, VT4, VT5, VT5, VT6, VT6, VT1, VT1, VT2, and the power order, the motor can work properly. For the 33 electric power tube, according to the VT1, VT2, VT3; VT2, VT3, VT4; VT3, VT4, VT5; VT4, VT5, VT6; VT5, VT6, VT1; VT6, VT1, VT2; VT1, VT2, VT3?? the order of electricity, the motor can operate normally.
2. power tube front stage drive circuit6 MOSFET power tube drive circuit to drive the electronic commutator before, because the 6 MOSFET tube 3 of the same bridge arm, the driving circuit of the same 3 bridge arm is the same, so the power tube pre driver circuit is composed of 3 groups of the same circuit structure, brushless the motor power is a typical tube before driving circuit for a brushless controller, there are 3 such circuits, driving 3 arm bridge.3. singlechip main control circuitThe MCU main control circuit is the core part of the brushless motor controller, motor, switch to the Holzer signal signal, overcurrent detection signal and braking signals are directly input to the microcontroller processing by the microcontroller, and the microcontroller output electronic commutator three arm drive signals to control the operation of the motor. The MCU main control circuit is the heart of the brushless motor controller. PIC16F72 microcontroller control chip is the mainstream of the current electric vehicle brushless motor controller, brushless motor is made of PIC16F72 brushless controller in the typical application circuit, including the main input and output signals of the brushless motor controller, SPSIG terminal signal, the signal after fifth feet of resistance R69 and R68 network into the microcontroller according to the change of the voltage signal of the MCU, foot, pulse width decided to output the driving signal, which determines the speed of the motor. Currently, the market for electric vehicles to turn the output signal voltage is generally 1~4.2V,
1. electronic commutatorThe basic difference between brushless motor and brush motor is that the electronic commutator of brushless motor instead of the mechanical commutator of brush motor, so the control method is very different, and the complexity is improved obviously. In the brushless motor controller, 6 power MOSFET tubes are used to form an electronic commutator. MOSFET VT1, a VT4 pipe bridge brushless motor phase winding A, VT3, VT6 bridge brushless motor phase winding B, VT5, VT2 bridge arm C brushless motor phase winding, in any case, the same bridge arm of the two tube can not turn on at the same time, otherwise you'll burn tube.
Basic principleElectric vehicle brushless controller is mainly composed of single-chip microcomputer control circuit, power tube pre driver circuit, electronic commutator, Holzer turn signal detection circuit, signal circuit, detection circuit, less power limiting / overcurrent detection circuit, signal circuit, brake speed limiting circuit, power supply circuit components, working principle of the main circuit are described below
