(May 16 2025) This software simulates a brushless DC motor and I wrote this software in C# programming language. This software is a robust tool for simulation of brushless DC motor yet it can be said that development of this software is still in progress because I have in mind some more features which I might integrate into it whenever my schedule allows. So I'll write enhanced version of this software when I'll get enough time but I ain't sure about when I'll get sufficient time.
(May 18 2025) Because I wanted to improve this software, I have incorporated some more improvements. I have written the enhanced version of this software. In future, if I will further enhance the software, I will update this repository or I'll create a new one for updated codebase.
- Computes phase currents based on applied voltages, back-EMF, phase resistance, and inductance (adjusted for magnetic saturation).
- Supports fault conditions like phase loss (zero current in a phase) or short circuits (low resistance between phases).
- Calculates back-EMF for each phase, using trapezoidal or sinusoidal waveforms depending on the motor type.
- Transforms phase currents to d-q frame for Field-Oriented Control (FOC) using Park and Clarke transforms.
- Models rotor motion using a second-order system (moment of inertia, friction, and torques).
- Calculates electromagnetic torque (based on currents and torque constant), cogging torque (due to slot effects), ripple torque (harmonic effects), and friction torque.
- Updates rotor angle and speed using a 4th-order Runge-Kutta method for numerical integration.
- Provides speed in RPM and commutation sector for 6-step control.
- Configurable motor type (trapezoidal or sinusoidal).
- Fault injection for phase loss or short circuits.
- Inductance variation due to magnetic saturation.
- Realistic torque components (cogging, ripple) for accurate dynamics.
- Simulates the power electronics driving the motor, converting DC link voltage to phase voltages.
- Supports two switching modes: Ideal (no losses) and Realistic (includes switching and conduction losses, dead time, and slew effects).
- Implements 6-step PWM (for trapezoidal control) or SVPWM (for sinusoidal FOC).
- Converts desired voltages to duty cycles, applying constraints (e.g., maximum DC link voltage).
- Calculates output voltages, accounting for MOSFET on-resistance and dead time distortion in realistic mode.
- Tracks switching losses (based on MOSFET switching energies) and conduction losses.
- Estimates inverter temperature based on power losses and supports thermal derating and shutdown when temperature exceeds thresholds.
- Realistic switching effects (dead time, rise/fall times); Thermal monitoring for protection; Flexible PWM strategies (6-step or SVPWM).
- Updates DC link voltage based on capacitor charge and inverter input current (sum of absolute phase currents).
- Models voltage drop due to ESR and recharge from a nominal voltage source.
- Ensures non-negative voltage.
- Supports overvoltage fault injection (e.g., setting nominal voltage to 32V, above the 30V threshold).
- Dynamic voltage response to load changes; Fault injection for overvoltage testing; Reset functionality to restore nominal conditions.
- Trapezoidal Control (6-Step PWM)
- Uses commutation sector (from rotor angle or fault-affected sensor) to energize two phases at a time.
- Employs PID controllers for current regulation in active phases, with torque demand derived from speed error.
- Applies voltages via the inverter in 6-step mode.
- Sinusoidal Control (FOC)
- PID Mode
- Converts speed error to q-axis current reference using a speed PID controller.
- Sets d-axis current reference to 0 for MTPA or adjusts for field weakening at high speeds.
- Uses two PID controllers to regulate d- and q-axis currents, computing d-q voltages.
- Applies inverse Park and Clarke transforms to convert d-q voltages to phase voltages.
- MPC Mode
- Delegates control to MPC controller model which computes optimal d- and q-axis voltages.
- Transforms voltages to phase voltages for inverter application.
- PID Mode
- MTPA: Maximizes torque per ampere for surface-mount PMSMs.
- Field Weakening: Reduces back-EMF at high speeds, respecting voltage and current limits.
- Adaptive Control: Adjusts PID gains based on estimated resistance and inductance.
- Integrates with fault manager to respect derating factors or stop operation during protection events.
- Uses a discretized state-space model to predict motor behavior.
- Defines cost function with weights for speed error, d- and q-axis current errors, and control effort.
- Performs grid search, respecting voltage and current constraints.
- Selects control inputs minimizing the cost over the prediction horizon (default N=5).
- Accounts for load torque and back-EMF as disturbances.
- Predictive control for improved performance; Constraint handling (voltage, current limits); Tunable parameters for flexibility.
- Computes control output using proportional, integral, and derivative terms.
- Includes integral anti-windup with configurable limits.
- Supports dynamic gain updates and setpoint changes.
- Resets integral and error terms when stopping the motor.
- Anti-windup for stable control.
- Flexible gain tuning.
- Uses Recursive Least Squares (RLS) to estimate motor parameters (phase resistance and inductance).
- Updates estimates based on phase voltages, currents, back-EMF, and current derivative.
- Uses a forgetting factor (lambda = 0.99) to prioritize recent data.
- Maintains a covariance matrix to adapt estimation gains.
- Constrains estimated parameters to realistic bounds (0.1–10 Ω, 0.1–10 mH).
- Skips estimation for low currents (|I| < 0.1 A) to avoid noise.
- Fault Injection
- Phase Loss: Sets a phase current to zero.
- Short Circuit: Connects two phases with low resistance (0.01 Ω).
- Sensor Failure: Simulates stuck or noisy rotor angle sensor.
- Overvoltage: Increases DC link voltage (e.g., to 32V).
- Overcurrent: Flags currents exceeding 10 A.
- Monitors overcurrent (>10 A) and overvoltage (>30 V), triggering shutdowns.
- Applies thermal derating when inverter temperature exceeds 80°C, shutting down at 120°C.
- Provides derating factor (0–1) based on temperature.
- Estimates inverter temperature based on power losses.
- Calculates temperature using a simplified model with thermal capacitance for inertia.
- Includes natural cooling toward ambient temperature (25°C).
- Ensures temperature remains above ambient.
- Supports derating and shutdown logic.
- Integrates all components, updating the system state at each time step.
- Executes simulation in 100 µs sub-steps (100 sub-steps per 10 ms) for numerical stability.
- Handles exceptions by stopping the motor and reporting errors.
- Sets load torque (0–0.1 Nm) and speed reference (0–3000 RPM).
- Centralized system integration.
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