SLLU374 November   2024 MCF8329A

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Hardware Design and Setup
    1. 2.1 Board Design
      1. 2.1.1 External MOSFET Selection
      2. 2.1.2 Gate Resistor Selection
      3. 2.1.3 Bootstrap and GVDD Capacitor Selection
      4. 2.1.4 Current Shunt Resistor Selection
      5. 2.1.5 VREG MOSFET Selection
      6. 2.1.6 Additional External Power Stage Components
  6. 3Connecting to the GUI
  7. 4Spinning Into Closed Loop
    1. 4.1 Essential Configuration
      1. 4.1.1 Loading Recommended Default Values
      2. 4.1.2 Setting Base Current
      3. 4.1.3 Setting Current Limits
      4. 4.1.4 Setting Voltage Limits
      5. 4.1.5 Input the Motor's Phase Resistance and Inductance
      6. 4.1.6 Maximum Electrical Speed (Hz)
      7. 4.1.7 Run MPET to Identify Motor Parameters
        1. 4.1.7.1 Skipping MPET Measurements
    2. 4.2 Testing for Successful Startup Into Closed Loop
  8. 5Basic Controls
    1. 5.1 Speed Input Mode
    2. 5.2 Preventing Back Spin of Rotor During Startup
    3. 5.3 Faster Startup Timing
    4. 5.4 Improving Speed Regulation
    5. 5.5 Limiting and Regulating Supply Power
    6. 5.6 MTPA Tuning
    7. 5.7 Motor Studio Optimization Wizards
  9. 6Fault Handling
    1. 6.1 MPET BEMF FAULT [MPET_BEMF_FAULT]
    2. 6.2 Abnormal BEMF Fault [ABN_BEMF]
    3. 6.3 Lock Current Limit [LOCK_LIMIT]
    4. 6.4 Hardware Lock Current Limit [HW_LOCK_LIMIT]
    5. 6.5 No Motor Fault [NO_MTR]
    6. 6.6 Abnormal Speed [ABN_SPEED]

5.6 MTPA Tuning

Maximum torque per ampere (MTPA) is a feature in the MCF8329A to maximize the torque generated per ampere of current for salient motors. To enable MTPA, set MTPA_EN to 1b and set the SALIENCY_PERCENTAGE to a non-zero value by setting the Lq and Ld values if they are provided in the device-specific data sheet.

MTPA Settings Figure 5-6 MTPA Settings
Note: If the motors Ld or saliency percentage is not known, the approximate SALIENCY_PERCENTAGE can be determined by following the steps below:
  1. Set the SALIENCY_PERCENTAGE to 0x1h
  2. Set the CTRL_MODE to Current Control mode
  3. Provide a speed command.
  4. While the motor is spinning, increment the SALIENCY_PERCENTAGE value by 1h until the motors speed begins to decrease.
Saliency Register Figure 5-7 Saliency Register