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Inverter.md

João Miguel Calado de Freitas requested to merge Inverter into master

Inverter Electro Overview

Overview [3.2]

  • The torque at the motor is controlled subject to the setpoint (accelerator position). The setpoint for the inverters is specified via a higher-level CAN controller.
  • Communication between the inverters and the higher-level controller takes place via a CAN bus 2.0 A. For the CAN message exchange, you can use fixed messages (mode 'Fixed CAN message configuration') or a application-specific configuration (mode 'Free CAN message configuration').
  • Temperature monitoring of the motor and inverter -Torque limitation in the event of overload ,excess temperature, undervoltage or overvoltage in the HV circuit

Servo motor overview [3.2.2]

  • Permanent-magnet synchronous servo motors
  • Mmax/MN = 2.1
  • Field-weakening(1) operation possible, speeds up to 20,000 rpm
  • Digital EnDat encoder
  • KTY temperature sensor
  • Shielded power cable
  • M12 plug for encoder signals and temperature monitoring

System diagram [3.5]

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Technical data – inverter [4.1]

see AMK.pdf in: https://drive.google.com/drive/u/1/folders/1cMZKcCi7UIxwNYLS1W5WkgUyVn7t01hj

Electric [6.3]

Charging and discharging the HV circuit capacitors [6.3.1]

  • The HV circuit capacitors in the inverters must be charged and discharged via an external charging device.
  • The HV circuit capacity is 300 μF in total (75 μF per inverter).
  • Calculation must be done to design discharge and precharge circuits

Cables/Connections

Power Eletronics ground connection [6.3.2]

  • A highly conductive connection must be implemented in the vehicle to provide the ground connection. This is used as a 0 VDC ground for all signal and operating voltages. For vehicles without a metal frame, a ground strap made from a braiding of fine copper wires can be used.

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Motor cable

  • The motor cable must be a shielded cable with tinned copper braiding. The motor cable shield must be connected to the shield for the unconnected cable end of the motor across the surface. Use non-adhesive heat-shrink tubing for this. Press the two pieces of shielding firmly together.

  • At the inverter, the shield must be placed across the surface of the cold plate. Ensure good contact with the cold plate.

    (!)The motor cable shield can prevent interference to a large extent. (Large diameter → skin effect)

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Tinned copper braiding.

HV cable

  • When greater than 1 m, the HV cable must have a copper shield. The end of the shield must be connected to the designated casing ground on the cold plate and on the battery side.

    (!)The end of the shield must NOT be connected to the negative terminal (-) of the HV battery.

Encoder temp. cable

  • The encoder cable shield must be grounded on both sides.
  • Via the circular connector casing on the motor and via the metalized D-SUB casing on the inverter (connection X131).

Power supply board

  • The power supply board GND is connected to the cold plate via the standoffs.

External power supply

  • The 0 VDC connection must be connected to the common vehicle ground.

GND and PE connection – power supply and logic board [6.3.2.1]

  • The cold plate is the PE ground for the inverters. The user is responsible for connecting the cold plate to the vehicle PE with a cable strand/ground strap (10 mm²). The user is responsible for producing the PE connection point on the cold plate. The user can choose where to place the connection point between the cooling channel.
  • The cooling channel must not be damaged when pre-drilling the connection screw for the PE connection.
  • The 0 VDC connection for an external 24 VDC power supply must also be connected to the vehicle PE by the user.

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The PE connection is the same for I1 +I2 and I3 +I4.

Configuration [6.4]

  • The inverter parameters are configured using the AMK AIPEX PRO startup software.
  • The FSE (Formula Student Eletric) function is a special item of firmware in which some of the functionality and setting options for the parameters differ from the default parameter description and the selection options in AIPEX PRO.

Motor parameters [6.4.1]

  • When the system is started up for the first time, the motor parameters are automatically transferred from the encoder database to the inverter.
  • The function is not performed if the motor parameters have already been entered manually.

Prerequisite for the automatic transfer of the data from the encoder database:

  • Encoder cable connected
  • Motor parameters have not already been changed manually
  • The data has been stored in the encoder at the factory

FSE parameters [6.4.3]

  • ID32798 'User list 1'

ID32798 'User list 1' is used to configure the torque limitation when operating within limits. For description of function: See 'Torque limitation' on page 82 (AMK datasheet).

  • Config this list in AIPEX software, choosing parameter values acoording to datasheet
  • Select List in AIPEX and change the data to readable decimal values

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  • The first ID is reserved for list size (Max = 245) , this is important if you want 'Fixed CAN message configuration' or 'Free CAN message configuration'. There are 12 messages in list 1 for fixed CAN BUS, if you want more feautures you can extend the number of parameters in the list, but you have to use Free CAN.

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  • Click the 'Folder' icon to open the list.
  • You can then enter the predefined values in the list elements (or change them).

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Edited by João Miguel Calado de Freitas

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