CN114537153A

CN114537153A - Isolation system for high-low voltage signals of motor controller

Info

Publication number: CN114537153A
Application number: CN202011336071.0A
Authority: CN
Inventors: 卢尚钰; 黄鹏辉; 潘毅宏; 丁祥根; 李育
Original assignee: Shanghai Automobile Gear Works
Current assignee: Shanghai Automobile Gear Works
Priority date: 2020-11-25
Filing date: 2020-11-25
Publication date: 2022-05-27
Anticipated expiration: 2040-11-25
Also published as: CN114537153B

Abstract

An isolation system for high and low voltage signals of a motor controller, the isolation system comprising: the method comprises the following steps: the low-voltage power supply, the isolated power supply, the low-voltage difference linear voltage stabilizer, the two isolated circuits, the first bus circuit and the second bus circuit are arranged at the low-voltage input interface, the isolated circuits are used for isolating the input low-voltage power supply, the CAN signal and the awakening signal, the communication between a high-voltage area and a low-voltage area is directly realized by changing the position of signal isolation without additionally adding devices, the running state of the motor controller CAN be more conveniently monitored more comprehensively, and the effect that the isolation is not needed when the signals inside the motor controller are interacted is achieved.

Description

Isolation system for high-low voltage signals of motor controller

Technical Field

The invention relates to a technology in the field of motor control, in particular to an isolation system for high-low voltage signals of a motor controller.

Background

The low-voltage power supply of the existing new energy automobile motor is provided by a low-voltage storage battery, and the high-voltage power supply is provided by a power battery. The motor controller adopts two ways of power supplies, in order to guarantee normal operating, prevent that the device from damaging, need keep apart high-low pressure in the controller inside. However, due to the cost and space limitations of the motor controller, the above-mentioned prior art cannot adopt a large number of isolated chips inside the controller, so that only in the large amount of information interaction existing between the high-voltage area and the low-voltage area, the most critical signal for the system operation is selected to be transmitted, and the operation state of the controller cannot be comprehensively monitored and accurately controlled.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides an isolation system for high-low voltage signals of a motor controller, wherein an isolation circuit is arranged at a low-voltage input interface to isolate input low-voltage power supply, CAN signals and wake-up signals, and the communication between a high-voltage area and a low-voltage area is directly realized by changing the isolation position of the signals without additionally adding devices, so that the running state of the motor controller CAN be more conveniently and more comprehensively monitored, and the effect of enabling the signals in the motor controller to be interacted without isolation is achieved.

The invention is realized by the following technical scheme:

the invention relates to an isolation system for high-low voltage signals of a motor controller, which comprises: low pressure plug connector, isolation power, low dropout linear regulator, two isolation circuit, first bus circuit and second bus circuit, wherein: the isolation power supply receives a low-voltage power supply signal from the low-voltage connector and respectively converts the low-voltage power supply signal into a power supply used by the functional circuit of the motor controller and a power supply used by the isolation circuit; the low-dropout linear regulator receives a low-voltage power supply signal from a low-voltage connector and respectively outputs power supplies to the first bus circuit and the two isolation circuits; the first bus circuit which has the awakening function and is always in the working state outputs a CAN awakening signal according to an awakening request from the CAN bus and generates a control signal of the first isolating circuit which is always in the working state after the CAN awakening signal and a key ignition signal from the low-voltage plug connector are jointly input into an OR gate so as to awaken a motor controller functional circuit; the motor controller functional circuit outputs power supplies of the second isolation circuit and the second bus circuit, communication signals and calibration signals of the first bus circuit and the second bus circuit are further transmitted when the second isolation circuit is in a working state, the communication function of the motor controller and the whole vehicle is achieved through the first bus circuit, and the calibration and debugging functions are achieved through the second bus circuit.

Technical effects

Compared with the prior art, the isolation circuit is arranged at the low-voltage input position of the motor controller, so that other devices of the motor controller are all positioned in a high-voltage area, and internal data interaction and control are not required to pass through the isolation circuit. By placing the isolation circuit at the low voltage input, the number of channels required is also significantly lower than in conventional schemes, which facilitates cost and space control.

Drawings

FIG. 1 is a schematic view of an isolation system of the present invention;

FIG. 2 is a schematic diagram of a motor controller with an isolation system according to the present invention.

Detailed Description

As shown in fig. 1, the present embodiment relates to a system for isolating high and low voltage signals of a motor controller, which includes: low pressure plug connector, isolation power, low dropout regulator LDO, two isolation circuit 1, 2, first bus circuit CAN0 and second bus circuit CAN1, wherein: the isolation power supply receives a low-voltage power supply signal KL30_ LV from a low-voltage connector and respectively converts the low-voltage power supply signal KL30_ LV into a power supply KL30_ HV power supply used by a power supply controller functional circuit and a 5V _ HV power supply used by the isolation circuit 1; the LDO receives a low-voltage power signal KL30_ LV power from a low-voltage connector and outputs 5V _ LV power to a first bus circuit CAN0 and two isolation circuits 1 and 2 respectively; the first bus circuit CAN0 with the function of waking up and always in working state outputs a CAN wake-up signal according to the wake-up request from the CAN bus and generates a control signal of the first isolation circuit 1 always in working state after being input into an OR gate together with a key ignition signal KL15 from a low-voltage plug connector so as to wake up the motor controller functional circuit; the motor controller function circuit outputs 5V power supplies of the second isolation circuit 2 and the second bus circuit CAN1, when the second isolation circuit 2 is in a working state, communication signals TXD0_ LV, TXD0_ HV, calibration signals CAN1H _ LV and CAN1L _ LV signals of the first bus circuit CAN0 and the second bus circuit CAN1 are further transmitted, the communication function of the motor controller and the whole vehicle is realized through the first bus circuit CAN0, and the calibration and debugging functions are realized through the second bus circuit CAN 1.

The KL30_ LV power supply supplies power for the 12V low voltage provided by the storage battery.

The power supply KL30_ HV power supply which is output by the isolated power supply and is used by the functional circuit of the motor controller completely places all functional circuits in the motor controller in a high-voltage area, so that direct data interaction can be carried out between the logic control part and the driving part.

The KL30_ LV power supply supplies power to the 12V low voltage power supply provided by the storage battery.

As shown in fig. 2, a motor controller with the isolation system according to this embodiment includes: the isolation system, the drive chip without isolation function, the drive amplifying circuit, the IGBT, the microcontroller chip, the CPLD, the drive part voltage sampling circuit, the power management module, the rotary transformer circuit and the peripheral circuit, wherein: in the low-voltage region: the microcontroller chip acquires the rotation speed and position information of the motor through the resolver circuit, acquires phase current information through the current sampling circuit, receives an instruction through the CAN bus and then sends a PWM waveform to the CPLD, and the CPLD controls the IGBT to be switched on and off according to a fault signal and the PWM waveform; in the high-pressure zone: the driving amplification circuit and the hardware ASC logic circuit control the IGBT, and the sampling circuit acquires high-voltage region state information and transmits the high-voltage region state information to the isolation chip; the isolation system receives a power supply from a low-voltage connector, a key ignition signal KL15 and a wake-up request from a CAN bus and outputs a wake-up signal to the power supply management module to enable the motor controller to work, and after the motor controller works, the microcontroller chip communicates with the outside through TXD0_ HV, RXD0_ LV, TXD1 and RXD1 to obtain a control command from the CAN bus. And then monitoring FLT, PWM feedback and current sampling value state information through control enable, RST, PWM, ASC request, SPI1 and SPI2 signals, so that the motor operates according to a control command.

The microcontroller chip in this embodiment is implemented using, but not limited to, infineon aurixtc 277.

The driving part voltage sampling circuit is directly connected to the microcontroller chip for sampling, and an AD conversion chip and an isolation chip are saved.

According to the invention, the isolation module is arranged at the input interface of the motor controller, namely, the isolation module is moved forward, so that the number of required isolation channels is saved, the cost is reduced, the number of signals in the motor controller is increased, and the operation of the motor controller can be controlled more accurately.

The foregoing embodiments may be modified in many different ways by those skilled in the art without departing from the spirit and scope of the invention, which is defined by the appended claims and all changes that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Claims

1. An isolation system for high and low voltage signals of a motor controller, comprising: low pressure plug connector, isolation power, low dropout linear regulator, two isolation circuit, first bus circuit and second bus circuit, wherein: the isolation power supply receives a low-voltage power supply signal from the low-voltage connector and respectively converts the low-voltage power supply signal into a power supply used by the functional circuit of the motor controller and a power supply used by the isolation circuit; the low-dropout linear regulator receives a low-voltage power supply signal from a low-voltage connector and respectively outputs power supplies to the first bus circuit and the two isolation circuits; the first bus circuit which has the awakening function and is always in the working state outputs a CAN awakening signal according to an awakening request from the CAN bus and generates a control signal of the first isolating circuit which is always in the working state after the CAN awakening signal and a key ignition signal from the low-voltage plug connector are jointly input into an OR gate so as to awaken a motor controller functional circuit; the motor controller functional circuit outputs power supplies of the second isolation circuit and the second bus circuit, communication signals and calibration signals of the first bus circuit and the second bus circuit are further transmitted when the second isolation circuit is in a working state, the communication function of the motor controller and the whole vehicle is achieved through the first bus circuit, and the calibration and debugging functions are achieved through the second bus circuit.

2. A motor controller having the isolation system of claim 1, comprising: the isolation system, the drive chip without isolation function, the drive amplifying circuit, the IGBT, the microcontroller chip, the CPLD, the drive part voltage sampling circuit, the power management module, the rotary transformer circuit and the peripheral circuit are arranged in a low-voltage area: the microcontroller chip acquires the rotation speed and position information of the motor through the resolver circuit, acquires phase current information through the current sampling circuit, receives an instruction through the CAN bus and sends a PWM waveform to the CPLD, and the CPLD controls the IGBT to be switched on and off according to a fault signal and the PWM waveform; in the high-pressure zone: the driving amplification circuit and the hardware ASC logic circuit control the IGBT, and the sampling circuit acquires high-voltage region state information and transmits the high-voltage region state information to the isolation chip; the isolation system receives a power supply from the low-voltage connector, a key ignition signal and a wake-up request from the CAN bus and outputs the wake-up signal to the power supply management module to enable the motor controller to work, and after the motor controller works, the microcontroller chip communicates with the outside to obtain a control instruction from the CAN bus and enable the motor to operate according to the control instruction.