Hello guys,
I am doing my Master thesis and my master thesis topic is to design a digital controller for controlling a temperature across the heater. For this I already designed a circuit using Ltspice and I am using MSP430f2619 microcontroller. I attached the Circuit and the program for this.
The problem is I should maintain a Constant temperature across the heater around 90 degree and for that I need minimum of 20v power supply and I am supplying it. The resistance of heater [Rh1 and Rh2 in circuit] changes as temperature changes and I should control only one resistor [Rh2(it is variable and varies if temperature changes)]. I should vary the voltage in order to vary the resistance which in turn maintains the constant temperature across the heater.I am using R4(in circuit) resistor to find the current through the heater. From microcontroller I should get a sine wave , the amplitude of the sine wave should vary in order to vary the voltage across the heater so it will changes the resistance and maintains a constant temperature.
In microcontroller program I am finding the error and using PI controller to regulate the voltage and I don't know how to find the Values of P and I and Depending on the error the sine wave amplitude should change.
The frquency should be around 600hz.
For now I try to write a program for DC supply from microcontroller 3v and I tried using PWM signal for controlling the voltage but it is not working and i just took random value for P and I .
I need to generate the sine wave from the microcontroller and not Dc supply and I can use either DAC or PWM to generate it.
I want to know how exactly I should writ the program and how exactly i should design PI controller for this application. Please help me . I am really stuck and it would be really helpful .Thanks in advance
I am doing my Master thesis and my master thesis topic is to design a digital controller for controlling a temperature across the heater. For this I already designed a circuit using Ltspice and I am using MSP430f2619 microcontroller. I attached the Circuit and the program for this.
The problem is I should maintain a Constant temperature across the heater around 90 degree and for that I need minimum of 20v power supply and I am supplying it. The resistance of heater [Rh1 and Rh2 in circuit] changes as temperature changes and I should control only one resistor [Rh2(it is variable and varies if temperature changes)]. I should vary the voltage in order to vary the resistance which in turn maintains the constant temperature across the heater.I am using R4(in circuit) resistor to find the current through the heater. From microcontroller I should get a sine wave , the amplitude of the sine wave should vary in order to vary the voltage across the heater so it will changes the resistance and maintains a constant temperature.
In microcontroller program I am finding the error and using PI controller to regulate the voltage and I don't know how to find the Values of P and I and Depending on the error the sine wave amplitude should change.
The frquency should be around 600hz.
For now I try to write a program for DC supply from microcontroller 3v and I tried using PWM signal for controlling the voltage but it is not working and i just took random value for P and I .
I need to generate the sine wave from the microcontroller and not Dc supply and I can use either DAC or PWM to generate it.
I want to know how exactly I should writ the program and how exactly i should design PI controller for this application. Please help me . I am really stuck and it would be really helpful .Thanks in advance
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