Modeling HVAC System And Design Of Embedded Controller

HVAC is often used to meet the needs of industrial process or satisfy human comfort. Due to humans or machines at all times by convection, radiation and evaporation which three heat transfer modes to discharge excess heat to keep your body temperature or machine temperature is within proper range. HVAC design of computer control system is based on the day-to-day running of the system is essentially a non-steady state of dynamic design, this resulted in HVAC system design and warm-up design of ventilating and air conditioning control system seriously out. Need a relatively advanced control algorithm for real-time control.Immune genetic algorithm, also known as immune algorithm, is subject to the principle of biological immune system inspired by the basic framework of the genetic algorithm, combined with the immune system of specific information processing mechanism developed a new algorithm can effectively improve the premature convergence defects, and significantly improves the global and local search capabilities. The immune PID parameter tuning algorithm is applied to technology, and significantly enhance the ability of PID parameter tuning to improve the efficiency of PID control for industrial control has a certain practical significance.Firstly, it is established to a model of HVAC system. Second, this is the method of the fuzzy immune HVAC system P,I,D parameter tuning, and ARM-based hardware platform, with RTX real-time operating system, to achieve this control algorithm, to design a control based on fuzzy immune algorithm device. In order to achieve the nonlinear, large delay, large inertia, multi-interference characteristics of central air conditioning system to achieve good control.The main research content and innovations are as follows:(1) Fuzzy immune PID control algorithm in the central air conditioning system in the study.HVAC control commonly used PI or PID control method and parameter tuning for P, I, D problem is key issue. Based on biological immune mechanisms, immune algorithm came into being, and fuzzy algorithm and immune algorithm combines PID control applied to the traditional method, fuzzy immune PID algorithm. This algorithm provides better control effects. First establish a nonlinear and lagged in this chapter, inertia, interference characteristics of central control models of HVAC systems, and fuzzy-immune-PID parameter tuning method applied to central air conditioning system control, simulation by Matlab, found that the control has a very good improvement.(2) ARM-based embedded controller hardware platform design.From ARM Holdings is a leading semiconductor intellectual property (IP) provider, and therefore the development of digital electronic products at the core position.ARM Cortex TM-M3 processor has excellent computational performance and exceptional system response to events, low dynamic and static power, high-performance low-cost features.STM32F103 series is based on the Cortex TM-M3 core, by a leading semiconductor manufacturer ST introduced SOC chip.The chip is clocked at 72MHz, integrated ADC, DAC, UART, I2C and other peripherals, very suitable for HVAC system main control chip. Based on STM32F103RBT6 we have designed an embedded hardware platforms, including the smallest MCU system; signal acquisition circuit; communication circuits; LCD interface circuit; control circuit of output circuit; data storage circuit; and other major parts. On this platform, it is realization to the software of fuzzy immune PID algorithm.(3) Fuzzy Immune Control Algorithm in the realization of the embedded controller.In STM32F103RBT6 hardware platform, the company launched by ARM MDK development environment, the use of widely used industrial control field of the RTX real-time operating system, the fuzzy immune algorithm in the central air conditioning system software research, design based on fuzzy immune PID algorithm embedded central HVAC controller. The software functions of embedded controller are TFT 1.6-inch true colour LCD human-computer interaction interface; upports USB, CAN, serial, and other means of communication; real-time clock, history, data acquisition, controlling output, the beep alarm and so on.