Temperature Control Simulation in C++

This tutorial demonstrates how to implement and simulate a temperature control system using C++. The system uses a proportional control algorithm to regulate temperature.

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C++ Controller Implementation

The following C++ class implements the temperature control logic with camelCase naming conventions.

TempControl.h

#pragma once

class TempControl {
public:
    TempControl(float setPoint, float proportionalGain);

    void update(float currentTemp);

    float getHeaterPower() const;
    float getTemperatureError() const;

private:
    float setPoint;
    float proportionalGain;
    float heaterPower;
    float temperatureError;
};

TempControl.cpp

#include "TempControl.h"

TempControl::TempControl(float setPoint, float proportionalGain)
    : setPoint(setPoint), proportionalGain(proportionalGain), heaterPower(0), temperatureError(0) {}

void TempControl::update(float currentTemp) {
    // Calculate error between setpoint and current temperature
    temperatureError = setPoint - currentTemp;

    // Apply proportional control
    heaterPower = proportionalGain * temperatureError;

    // Limit heater power between 0 and 100%
    if (heaterPower > 100.0f) {
        heaterPower = 100.0f;
    } else if (heaterPower < 0.0f) {
        heaterPower = 0.0f;
    }
}

float TempControl::getHeaterPower() const {
    return heaterPower;
}

float TempControl::getTemperatureError() const {
    return temperatureError;
}

This class calculates the heater power based on the error between the desired temperature (setPoint) and the current temperature.

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Simulation Class Integration

The TempControl class is integrated into a simulation class that inherits from the CppModel framework’s Simulation class.

SimulateTempControl.h

#pragma once
#include <cppmodel/Simulation.h>
#include "TempControl.h"

class SimulateTempControl : public CppModelBase::Simulation
{
public:
    SimulateTempControl(std::string apiKey);
    void runCyclic(double simulationTime) override;

private:
    TempControl* tempController;
};

SimulateTempControl.cpp

#include "SimulateTempControl.h"

SimulateTempControl::SimulateTempControl(std::string apiKey)
    : CppModelBase::Simulation(apiKey), tempController(nullptr)
{
    name = "TempControl";

    time = 60;       // Run simulation for 60 seconds
    stepSize = 0.1;  // Simulation step size, 100ms
}

void SimulateTempControl::runCyclic(double simulationTime)
{
    if (tempController == nullptr) {
        // Initialize the TempControl object with inputs from CppModel
        float setPoint = inputs["Setpoint"];
        float proportionalGain = inputs["ProportionalGain"];
        tempController = new TempControl(setPoint, proportionalGain);
    }

    // Read current temperature input
    float currentTemp = inputs["CurrentTemperature"];

    // Update the temperature controller
    tempController->update(currentTemp);

    // Update the simulation outputs
    outputs["HeaterPower"] = tempController->getHeaterPower();
    outputs["TemperatureError"] = tempController->getTemperatureError();
}

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Main Program

The following main.cpp file runs the simulation:

main.cpp

#include "SimulateTempControl.h"

int main(void)
{
    SimulateTempControl sim(CPPMODEL_API_KEY);
    sim.simulate();
    return 0;
}

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CMake Configuration

To compile the project and link it with the CppModel library, use the following CMake configuration:

CMakeLists.txt

project(TempControlCpp)

add_definitions(-DCPPHTTPLIB_OPENSSL_SUPPORT)

add_executable(SimulateTempControl TempControl.cpp SimulateTempControl.cpp main.cpp)
if (WIN32)
  target_link_libraries(SimulateTempControl CppModelBase crypto ssl crypt32 ws2_32)
else()
  target_link_libraries(SimulateTempControl CppModelBase crypto ssl)
endif()

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Simulation Results

After execution, the results of the simulation can be found in workspace.cppmodel.com.