SLLU363 may   2023 MCF8315A

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
    1. 1.1 Hardware and GUI Setup
      1. 1.1.1 Jumper Configuration
      2. 1.1.2 External Connections
      3. 1.1.3 Connecting to the GUI
        1. 1.1.3.1 Connect to computer
        2. 1.1.3.2 Connect to the GUI
        3. 1.1.3.3 Verify Hardware Connection
  5. 2Essential Controls
    1. 2.1 Recommended Default Values
    2. 2.2 Device and Pin Configuration
      1. 2.2.1 Speed Input Mode
    3. 2.3 Control Configuration - Motor Parameters
      1. 2.3.1 Maximum Motor Electrical Speed (Hz)
    4. 2.4 Control configuration - Closed Loop
      1. 2.4.1 Current Limit for Torque PI Loop
    5. 2.5 Testing for Successful Startup into Closed Loop
    6. 2.6 Fault Handling
      1. 2.6.1 MPET IPD Fault [MPET_IPD_Fault]
      2. 2.6.2 MPET BEMF Fault [MPET_BEMF_Fault]
      3. 2.6.3 Abnormal BEMF Fault [ABN_BEMF]
      4. 2.6.4 Lock Current Limit [LOCK_LIMIT]
      5. 2.6.5 Hardware lock Current Limit [HW_LOCK_LIMIT]
      6. 2.6.6 No Motor Fault [NO_MTR]
  6. 3Basic Controls
    1. 3.1 Device and Pin Configuration
      1. 3.1.1 Power Saver or Sleep Mode for Battery Operated Applications
      2. 3.1.2 Direction and Brake Pin Override
    2. 3.2 System Level Configuration
      1. 3.2.1 Tracking Motor Speed Feedback in Real Time
      2. 3.2.2 Improving Acoustic Performance
      3. 3.2.3 Protecting the Power supply
      4. 3.2.4 Monitoring Power Supply Voltage Fluctuations for Normal Motor Operation
    3. 3.3 Control Configurations
      1. 3.3.1  Motor Parameter Estimation to Minimize Motor Parameter Variation Effects
      2. 3.3.2  Initial Speed Detection of the Motor for Reliable Motor Resynchronization
      3. 3.3.3  Unidirectional Motor Drive Detecting Backward Spin
      4. 3.3.4  Preventing Back Spin of Rotor During Startup
      5. 3.3.5  Faster Startup Timing
      6. 3.3.6  Gradual and Smooth Start up Motion
      7. 3.3.7  Improving Speed Regulation
      8. 3.3.8  Stopping Motor Quickly
      9. 3.3.9  Preventing Supply Voltage Overshoot During Motor Stop.
      10. 3.3.10 Protecting Against Rotor Lock or Stall Condition
      11. 3.3.11 Maximizing Thermal Efficiency and Increasing Thermal Performance
      12. 3.3.12 Mitigating Electromagnetic Interference (EMI)
      13. 3.3.13 Faster deceleration

3.3.5 Faster Startup Timing

Startup time is the time taken for the motor to reach the target speed from zero speed. For applications that require quick startup time, we recommend choosing either Initial Position Detection (IPD) or Slow first cycle as the startup method.

Option 1: Initial Position Detection (IPD)

Step 1: Select IPD [MTR_STARTUP] as the motor startup method.

Step 2: Increase IPD current threshold [IPD_CURR_THR] to rated current of the motor.

Step 3: Increase IPD clock value [IPD_CLK_FREQ] to higher frequency up to a value where the device does not trigger IPD frequency fault. Check Section 3.3.4 (Step 3) for more details.

Step 4: Select IPD repeating times [IPD_REPEAT] to 1 time.

Step 5: Select Open loop current limit [OL_ILIMIT] to be the same as Current limit for Torque PI Loop [ILIMIT].

If the device triggers Lock current limit [LOCK_LIMIT], it is recommended to increase [LOCK_ILIMIT] upto the stall current of the motor. Configuring this to a value higher than motor stall current will overheat or damage the motor.

Step 6: Increase Open loop acceleration coefficient A1 [OL_ACC_A1] and Open loop acceleration coefficient A2 [OL_ACC_A2].

Note:

A1 and A2 can be increased until open loop current reaches Lock detection current threshold [LOCK_ILIMIT]. Open loop current can be measured using oscilloscope. Increasing Open loop acceleration coefficient A1 [OL_ACC_A1] and Open loop acceleration coefficient A2 [OL_ACC_A2] might trigger LOCK_LIMIT. If this happens, reduce A1 and A2 until LOCK_LIMIT no longer triggers.

Step 7: Select Minimum BEMF for handoff [AUTO_HANDOFF_MIN_BEMF] to 0 mV.

If the device triggers Abnormal BEMF [ABN_BEMF] fault, then it is recommended to increase the [AUTO_HANDOFF_MIN_BEMF].

Step 8: Keep increasing ramp rate for reducing difference between estimated theta and open loop theta to 2 deg/ms.

Step 9: Increase Closed loop acceleration rate [CL_ACC]

Note:

LOCK_LIMIT fault handling:

Closed loop acceleration rate [CL_ACC] can be increased until closed loop current reaches Lock detection current threshold [LOCK_ILIMIT]. Closed loop current can be measured using oscilloscope. Increasing closed loop acceleration rate [CL_ACC] might trigger LOCK_LIMIT. If this happens, reduce closed loop acceleration rate [CL_ACC] until no longer triggers.

Option 2: Slow first cycle

Step 1: Select Slow first cycle as the motor startup method in [MTR_STARTUP].

Step 2: Select Align or slow first cycle current limit [ALIGN_OR_SLOW_CURRENT_ILIMIT] to be the same as Current limit for Torque PI loop [ILIMIT].

Step 3: Keep increasing Align or slow first cycle current ramp rate [ALIGN_SLOW_RAMP_RATE] until the open loop current reaches 100% of the rated current of the motor.

Step 4: Follow Step 5 to Step 9 in Option 1.