CN114537153B

CN114537153B - Isolation system for high-low voltage signals of motor controller

Info

Publication number: CN114537153B
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: 2023-09-26
Anticipated expiration: 2040-11-25
Also published as: CN114537153A

Abstract

An isolation system for high and low voltage signals of a motor controller, the isolation system comprising: comprising the following steps: the invention sets an isolation circuit at the low-voltage input interface to isolate the input low-voltage power supply, CAN signal and wake-up signal, and directly realizes the communication between the high-voltage area and the low-voltage area by changing the isolation position of the signal without adding extra devices, thereby more conveniently and comprehensively monitoring the running state of the motor controller and achieving the effect that the signal interaction inside the motor controller does not need to be isolated.

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 and 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 paths of power supply, and in order to ensure normal operation and prevent damage of devices, high and low voltages are required to be isolated in the controller. However, due to the cost and space limitation of the motor controller, the above-mentioned prior art cannot adopt a large number of isolation chips inside the controller, so that the most critical signals for the system operation can be selected for transmission only in a large amount of information interaction between the high-voltage area and the low-voltage area, 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 an input low-voltage power supply, a CAN signal and a wake-up signal, and under the condition that no additional device is required to be added, the communication between a high-voltage area and a low-voltage area is directly realized by changing the isolation position of the signals, so that the running state of the motor controller CAN be monitored more conveniently and comprehensively, and the effect that the signal interaction inside the motor controller does not need to be isolated is achieved.

The invention is realized by the following technical scheme:

the invention relates to an isolation system for high and low voltage signals of a motor controller, which comprises: the low-voltage power supply comprises a low-voltage plug connector, an isolated power supply, a low-voltage difference linear voltage stabilizer, two isolated circuits, a first bus circuit and a second bus circuit, wherein: the isolation power supply receives the low-voltage power supply signal from the low-voltage connector and converts the low-voltage power supply signal into power supplies for the motor controller functional circuit and the isolation circuit respectively; the low-voltage difference linear voltage stabilizer receives the low-voltage power supply signal from the low-voltage connector and outputs power supply to the first bus circuit and the two isolation circuits respectively; the first bus circuit with the wake-up function and always in the working state outputs a CAN wake-up signal according to a wake-up request from a CAN bus and generates a control signal of the first isolation circuit always in the working state after being input into an OR gate together with a key ignition signal from a low-voltage plug-in unit so as to wake up a motor controller function circuit; the motor controller functional circuit outputs the power supply of the second isolation circuit and the second bus circuit, when the second isolation circuit is in a working state, communication signals and calibration signals of the first bus circuit and the second bus circuit are further transmitted, the communication function between the motor controller and the whole vehicle is realized through the first bus circuit, and the calibration and debugging functions are realized through the second bus circuit.

Technical effects

Compared with the prior art, the invention places the isolation circuit at the low-voltage input position of the motor controller, so that other devices of the motor controller are all in a high-voltage region, and internal data interaction and control are not needed to pass through the isolation circuit. The number of channels required to place the isolation circuit at the low voltage input is also significantly lower than conventional approaches, facilitating cost and space control.

Drawings

FIG. 1 is a schematic diagram 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, this embodiment relates to a system for isolating high and low voltage signals of a motor controller, including: the low-voltage plug-in unit, isolated power supply, low dropout linear regulator LDO, two isolation circuits 1, 2, first bus circuit CAN0 and second bus circuit CAN1, wherein: the isolation power supply receives the low-voltage power supply signal KL30_LV from the low-voltage connector and converts the low-voltage power supply signal KL30_LV into a power supply KL30_HV power supply for a motor controller functional circuit and a 5V_HV power supply for the isolation circuit 1 respectively; the low dropout linear regulator LDO receives a low voltage power signal KL30_LV power supply from the low voltage connector and outputs 5V_LV power supply to the first bus circuit CAN0 and the two isolation circuits 1 and 2 respectively; the first bus circuit CAN0 with the wake-up function and always in the working state outputs a CAN wake-up signal according to a wake-up request from a CAN bus and inputs the CAN wake-up signal and a key ignition signal KL15 from a low-voltage plug-in unit together with an OR gate to generate a control signal of the first isolation circuit 1 always in the working state so as to wake up a motor controller function circuit; the motor controller functional circuit outputs a second isolation circuit 2 and a 5V power supply of a second bus circuit CAN1, when the second isolation circuit 2 is in a working state, communication signals TXD0_LV, TXD0_HV, a calibration signal CAN1H_LV and a CAN1L_LV 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 function is realized through the second bus circuit CAN 1.

The KL30_LV power supply supplies 12V low-voltage power to the storage battery.

The power KL30_HV power supply used by the functional circuit of the power supply controller for isolating the power supply output is used for placing all the functional circuits in the motor controller in a high-voltage area, so that direct data interaction can be performed between the logic control part and the driving part.

The KL30_LV power supply supplies 12V low-voltage power to the storage battery.

As shown in fig. 2, a motor controller with the isolation system according to the present embodiment includes: above-mentioned isolation system, do not have drive chip, drive amplifier circuit, IGBT, microcontroller chip, CPLD, drive partial voltage sampling circuit, power management module, rotation change circuit and peripheral circuit of isolation function, wherein: in the low pressure region: the microcontroller chip obtains the rotating speed and position information of the motor through the rotating and changing circuit, obtains phase current information through the current sampling circuit, receives instructions through the CAN bus and then sends PWM waveforms to the CPLD, and the CPLD controls the IGBT to be turned on and turned off according to the fault signals and the PWM waveforms; in the high pressure region: the drive amplifying circuit and the hardware ASC logic circuit control the IGBT, and the sampling circuit obtains the state information of the high-voltage area and transmits the state information to the isolation chip; the isolation system receives a power supply from the low-voltage connector, a key ignition signal KL15 and a wake-up request from the CAN bus and outputs the wake-up signal to the power management module to enable the motor controller to work, and when the motor controller works, the microcontroller chip communicates with the outside through TXD0_HV, RXD0_LV, TXD1 and RXD1 to acquire a control instruction from the CAN bus. And then, monitoring FLT, PWM feedback and current sampling value state information through control enabling, RST, PWM, ASC request, SPI1 and SPI2 signals, so that the motor operates according to a control instruction.

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

The driving part voltage sampling circuit is directly connected to the micro controller chip for sampling, so that the AD conversion chip and the 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 partially modified in numerous ways by those skilled in the art without departing from the principles and spirit of the invention, the scope of which is defined in the claims and not by the foregoing embodiments, and all such implementations are within the scope of the invention.

Claims

1. An isolation system for high and low voltage signals of a motor controller, comprising: the low-voltage power supply comprises a low-voltage plug connector, an isolated power supply, a low-voltage difference linear voltage stabilizer, two isolated circuits, a first bus circuit and a second bus circuit, wherein: the isolation power supply receives the low-voltage power supply signal from the low-voltage connector and converts the low-voltage power supply signal into power supplies for the motor controller functional circuit and the isolation circuit respectively; the low-voltage difference linear voltage stabilizer receives the low-voltage power supply signal from the low-voltage connector and outputs power supply to the first bus circuit and the two isolation circuits respectively; the first bus circuit with the wake-up function and always in the working state outputs a CAN wake-up signal according to a wake-up request from a CAN bus and generates a control signal of the first isolation circuit always in the working state after being input into an OR gate together with a key ignition signal from a low-voltage plug-in unit so as to wake up a motor controller function circuit; the motor controller functional circuit outputs the power supply of the second isolation circuit and the second bus circuit, when the second isolation circuit is in a working state, communication signals and calibration signals of the first bus circuit and the second bus circuit are further transmitted, the communication function between the motor controller and the whole vehicle is realized through the first bus circuit, and the calibration and debugging functions are realized through the second bus circuit.

2. A motor controller having the isolation system of claim 1, comprising: the isolation system, the driving chip without isolation function, the driving amplifying circuit, the IGBT, the microcontroller chip, the CPLD, the driving part voltage sampling circuit, the power management module, the spin-on circuit and the peripheral circuit are arranged in a low-voltage area: the microcontroller chip acquires the rotating speed and position information of the motor through the rotary transformer 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 turned on and turned off according to the fault signal and the PWM waveform; in the high pressure region: the drive amplifying circuit and the hardware ASC logic circuit control the IGBT, and the sampling circuit obtains the state information of the high-voltage area and transmits the 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 management module to enable the motor controller to work.