SLAU927A March   2024  – June 2024 MSPM0G3507

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Hardware Setup
    1. 2.1  EVM Hardware Setup
      1. 2.1.1 EVM Hardware Support
    2. 2.2  Pin Configurations for IPD Usage
    3. 2.3  Pin Configurations for PWM Outputs
    4. 2.4  Pin Configurations for ADC Currents
    5. 2.5  Pin Configurations for ADC Voltages
    6. 2.6  Pin Configurations for Faults
    7. 2.7  Pin Configurations for GPIO Output Functions
    8. 2.8  Pin Configurations for SPI Communication
    9. 2.9  Pin Configurations for UART Communication
    10. 2.10 External Connections for Evaluation Boards
  6. 3Software Setup
    1. 3.1 Software Support
  7. 4GUI Setup
  8. 5Register Map
    1. 5.1 User Control Registers (Base Address = 0x20200400h)
    2. 5.2 User Input Registers (Base Address = 0x20200000h)
    3. 5.3 User Status Registers (Base Address = 0x20200430h)
  9. 6Basic Tuning
    1. 6.1 System Configuration Parameters
      1. 6.1.1 Configuring System Parameters from GUI
      2. 6.1.2 Motor Resistance in Milliohms (mΩ)
      3. 6.1.3 Motor Inductance in Microhenries (μH)
      4. 6.1.4 Saliency of IPMSM Motor
      5. 6.1.5 Motor BEMF Constant
      6. 6.1.6 Base Voltage (V)
      7. 6.1.7 Base Current (A)
      8. 6.1.8 Maximum Motor Electrical Speed (Hz)
    2. 6.2 Control Configurations for Basic Motor Spinning
      1. 6.2.1 Basic Motor Startup
        1. 6.2.1.1 Disable ISD
        2. 6.2.1.2 Motor Start Option - Align
        3. 6.2.1.3 Motor Open Loop Ramp
        4. 6.2.1.4 Motor Open Loop Debug
      2. 6.2.2 Controller Configuration for spinning the Motor in Closed Loop
        1. 6.2.2.1 PI Controller Tuning for Closed Loop Speed Control
        2. 6.2.2.2 Testing for Successful Startup Into Closed Loop
    3. 6.3 Fault Handling
      1. 6.3.1 Abnormal BEMF Fault [ABN_BEMF]
      2. 6.3.2 Monitoring Power Supply Voltage Fluctuations for Voltage Out of Bound Faults
      3. 6.3.3 No Motor Fault [NO_MTR]
  10. 7Advanced Tuning
    1. 7.1 Control Configurations Tuning
      1. 7.1.1  Initial Speed Detection of the Motor for Reliable Motor Resynchronization
      2. 7.1.2  Unidirectional Motor Drive Detecting Backward Spin
      3. 7.1.3  Preventing Back Spin of Rotor During Startup
      4. 7.1.4  Gradual and Smooth Start up Motion
      5. 7.1.5  Faster Startup Timing
      6. 7.1.6  Stopping Motor Quickly
      7. 7.1.7  Flux Weakening : Operating Motor at Speeds Higher than Rated Speed
      8. 7.1.8  Maximum Torque Per Ampere : Improve Efficiency of IPMSM Motors
      9. 7.1.9  Preventing Supply Voltage Overshoot During Motor Stop.
      10. 7.1.10 Protecting the Power Supply
      11. 7.1.11 FOC Bandwidth Selection
  11. 8Hardware Configurations
    1. 8.1 Direction Configuration
    2. 8.2 Brake Configuration
    3. 8.3 Main.h Definitions
    4. 8.4 Real Time Variable Tracking
  12. 9Revision History

7.1.10 Protecting the Power Supply

Protecting the power supply from drawing higher current or potential voltage overshoots is important in battery operated applications or applications that do not have an internal overcurrent or overvoltage protection built into the power supply.

Step 1: When the load on the motor increases, the device draws higher current from the power supply. To limit the current drawn from the power supply, enable bus current limit [BUS_CURRENT_LIMIT_ENABLE] and configure the bus current limit [BUS_CURRENT_LIMIT] to protect the power supply from drawing higher current.

For example, limiting the current drawn from power supplies such as batteries is required because the battery life depends on the charge and discharge cycles. Enabling the bus current limit limits the power supply current by limiting the speed of the motor.

Step 2: When a command is issued for the motor to decelerate, based on the deceleration rate, energy from the motor can be pumped back to the power supply, increasing the supply voltage to levels that are possibly unsafe for electronics. Enable the antivoltage surge [AVS] to protect the power supply from voltage overshoots that override any deceleration limit set by any other register and automatically apply a safe deceleration rate.

Figure 7-2 shows overshoot in power supply voltage when AVS is disabled. Motor decelerates from 100% duty cycle to 10% duty cycle at a deceleration rate of 70000Hz/s. Figure 7-3 shows no overshoot in power supply voltage when AVS is enabled.

Power Supply Voltage and Phase Current Waveform When AVS is DisabledFigure 7-2 Power Supply Voltage and Phase Current Waveform When AVS is Disabled
Power Supply Voltage and Phase Current Waveform When AVS is EnabledFigure 7-3 Power Supply Voltage and Phase Current Waveform When AVS is Enabled