Design and application of handheld auto-tuning pid instrument used in HVAC

The PID control algorithm commonly used in current domestic HVAC system. The difficulty status that the engineering staff encounter at the scene when they tune the parameter were given in this paper. A kind of handheld auto-tuning PID controller, based on frequency domain identification was designed, can identify online system model and give the best control parameters of the the current running system. As examples of application, the paper proposed the use of the controller in the HVAC system, the test results showed that the controller provided the process control engineers with an effective tool. It guaranteed the control parameter optimization, made the tuning time shorter in the HVAC system, and ensured the energy-saving effect of the air-conditioning system.