Design and implementation of digital PID controller using FPGA for precision temperature control

In this paper, design scheme for implementation of digital PID controller using FPGA based microcontroller core is presented for temperature control system. The differential equation includes different controller gains, required to be tuned for desired output response. Usually PID control is much used for second or higher order systems. On the other hand, PI and PD controllers are preferred for first order systems. Here controller is implemented to fulfill the demand of achieving and maintaining the temperature of an Al plate to the desired set point temperature with control precision better than 0.1°C, acceptable rise time and settling time. In implementation load used is a first order system as it has single heat transfer element. For FPGA implementation of PID, VHDL is used for code development. Microcontroller core is used for configuring and interfacing to peripherals using C. Libero IDE is used to develop, simulate, synthesis and place & route the design.