Field-Oriented Control (FOC) is a technique used to control the torque and speed of three-phase AC induction motors and permanent magnet synchronous motors (PMSMs). Implementing FOC on a microcontroller like the MPC5604P, which is part of NXP's Power Architecture family, involves several steps, including hardware setup, software development, and tuning of control parameters.

MPC5604P Microcontroller: Ensure you have the necessary development tools, such as a debugger (e.g., JTAG or Nexus) and a development board.

Power Stage: You need an inverter bridge (typically using IGBTs or MOSFETs) to drive the motor.

Current Sensors: These are essential for measuring the phase currents, which are used in the FOC algorithm.

Position/Speed Sensor: Depending on the motor type, you may need an encoder or resolver to measure rotor position and speed

Gate Drivers: To drive the power switches in the inverter.

Development Environment: Use an IDE like S32 Design Studio for Power Architecture or any other compatible IDE.

FOC Algorithm: Implement the FOC algorithm, which typically includes the following steps:

Clarke Transform: Converts three-phase currents (Ia, Ib, Ic) to two-phase stationary reference frame (Iα, Iβ).

Park Transform: Converts the two-phase stationary reference frame to the rotating reference frame (Id, Iq).

PI Controllers: Use PI controllers to regulate the Id and Iq currents. Id is typically controlled to be zero for maximum torque per ampere (MTPA) in PMSMs.

Inverse Park Transform: Converts the rotating reference frame back to the stationary reference frame.

Space Vector Modulation (SVM): Generates PWM signals to control the inverter.

ADC Configuration: Configure the ADC to sample the phase currents and DC bus voltage.

PWM Configuration: Set up the PWM module to generate the necessary signals for the inverter.

Timer Configuration: Use timers for precise control of the PWM signals and sampling intervals.

Current Loop Tuning: Tune the PI controllers for the Id and Iq currents. This involves setting the proportional and integral gains to achieve the desired response.

Speed Loop Tuning: If you have a speed control loop, tune the PI controller for speed regulation.

Sensor Calibration: Calibrate the position/speed sensor to ensure accurate measurements.

Safety Features: Implement safety features such as overcurrent protection, overvoltage protection, and thermal protection.

Here is a simplified example of how you might structure your FOC code:

#include "MPC5604P.h"

// Function prototypes
void FOC_Init(void);
void FOC_Update(void);
void ADC_Handler(void);
void PWM_Update(float Vα, float Vβ);

// Global variables
float Ia, Ib, Ic;
float Iα, Iβ;
float Id, Iq;
float Vd, Vq;
float Vα, Vβ;
float theta;

void main(void) {
    FOC_Init();
    while (1) {
        FOC_Update();
    }
}

void FOC_Init(void) {
    // Initialize ADC, PWM, timers, etc.
}

void FOC_Update(void) {
    // Sample currents
    ADC_Handler();

    // Clarke Transform
    Iα = Ia;
    Iβ = (Ia + 2 * Ib) / sqrt(3);

    // Park Transform
    Id = Iα * cos(theta) + Iβ * sin(theta);
    Iq = -Iα * sin(theta) + Iβ * cos(theta);

    // PI Controllers for Id and Iq
    Vd = PI_Controller_Id(Id_ref - Id);
    Vq = PI_Controller_Iq(Iq_ref - Iq);

    // Inverse Park Transform
    Vα = Vd * cos(theta) - Vq * sin(theta);
    Vβ = Vd * sin(theta) + Vq * cos(theta);

    // Space Vector Modulation
    PWM_Update(Vα, Vβ);
}

void ADC_Handler(void) {
    // Read ADC values for Ia, Ib, Ic
}

void PWM_Update(float Vα, float Vβ) {
    // Update PWM registers based on Vα and Vβ
}

Implementing FOC on the MPC5604P involves a combination of hardware setup, software development, and tuning. The example provided is a simplified overview, and actual implementation will require detailed knowledge of the microcontroller's peripherals and the specific motor characteristics. Always refer to the microcontroller's reference manual and the motor's datasheet for detailed information.

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