Controller Research Of VRV Central Air-Conditioning Based On Embedded System

VRV (Variable Refrigerant Volume) central air conditioning system is more and morewidely used in all kinds of buildings because of its energy efficiency and energy savingand comfort. At present, the research on VRV system is focus on the control strategy andcontroller design, and how to realize the operation of the stability and reliability. In view ofthe above content, this thesis conducted research in the following two aspects.This thesis analyzed the VRV system control technology development presentsituation at home and abroad, then combined fuzzy control and PID control method andcarried on the Matlab simulation research for VRV system. After that, this thesis designed aembedded terminal controller based on the control strategy. Hardware was a embeddeddevelopment board based on ARM11kernel and S3C6410processor; it selected WindowsCE6.0as the operating system on account of its widely used in industrial control field. Thecontroller included the design of peripheral circuit, cutting and burning of the kernel, thedesign of driver and application. Realized the following functions:(1)collect the refrigeranttemperature of the evaporator inlet and outlet;(2)take fuzzy PID operation of the deviationand deviation rate with superheat;(3)output analog voltage signal to control electronicexpansion valve.Through the simulation experiment concluded that fuzzy PID strategy can achieve astable status of superheat accurately and little overshoot. The ARM11embedded controllerbased on this control strategy is good to meet the system requirements. It’s powerful dataprocessing ability can realize the optimization of the air conditioning system operation.