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1、本科毕业设计外文文献及译文文献、资料题目：Energy and Buildings文献、资料来源：期刊SciVerse Sciencedirect文献、资料发表（出版）日期2013年1月21日院 （部）： 信息与电气工程学院专 业： 电气工程及其自动化班 级： 电气134姓 名： 学 号： 指导教师： 翻译日期： 2017.3.7山东建筑大学毕业设计外文文献及译文外文文献：Energy and Buildings abstract In order to control the temperature and humidity of the greenhouse environment, an
2、 intelligent air conditioner based on an air conditioner, a ZigBee wireless sensor network (WSN) and a fuzzy controller is proposed, designed, and realized in this study. The valves in the intelligent air conditioner are controlled to allow it to operate in one of these four modes: dehumidier, heate
3、r, cooler, and fan blower. The multipoint ZigBee WSN sensor nodes are used to measure the temperature and humidity in the greenhouse.The system uses PIC18F4520 microcontroller as its core to develop the fuzzy controller. Based on fuzzy inference system, the fuzzy controller processes and analyze the
4、 temperature and humidity data collected from the sensors imbedded in the air inlet of the air conditioner and from ZigBee WSN sensor nodes, determines the best operation mode, and issues control commands to maintain a suitable greenhouse environment. The test results show that the performance of th
5、e intelligent air conditioner closely matches the goal and satises the requirements preset by the operator. In addition, a graphical user interface (GUI) is designed to control and monitor the temperature and relative humidity in the greenhouse environment, and the Elipse Power Studio monitoring sof
6、tware is used to construct a monitor platform with internet browser capability. 1. Introduction Agriculture has always been one of the most important industries of developing countries to support their economic development. As time changes and after the WTO (World Trade Organization) was found, it i
7、s clear that ne agriculture is inevitable if future development is to continue. Conventional agriculture is a labor-intense industry and requires a lot of manpower, as opposed to ne agriculture where technologies help to transform many aspects of agriculture. The key to the transformation is the use
8、 of automation equipments to replace human labor. Greenhouse cultivations are widely adopted for market toward high technology threshold and products with high additive value, and to maintain plantation growth by quality control and unaffected by weather, insects, or diseases. The three physical qua
9、ntities which are most important in greenhouse indoor environment control are the temperature, relative humidity, and light. Heat conservation or heater may be applied when the temperature inside the green house is too low. When the indoor temperature is too high, natural or forced ventilation may b
10、e applied if the outdoor temperature is lower than the indoor temperature. The water vapor sprayer or the air cooler may be applied if the outdoor temperature is higher than the indoor temperature. When the indoor humidity is too high, dehumidier or natural moisture absorbing mechanism may be utiliz
11、ed to remove moisture in the air. When the indoor humidity is too low, humidier or water vapor sprayer may be used to regulate the indoor air humidity. Green plants need adequate sunlight for photosynthesis. Shades are used to block excessive sunlight which may also lead to temperature rise, and art
12、icial light is introduced when the sunlight level is low. In the original state, the greenhouse already has shade nets, water sprayer and other facilities to roughly regulate sunlight, temperature and humidity according to the exterior factor. This study proposes the use of an intelligent air condit
13、ioner with heating, cooling and dehumidifying functions that is capable of regulating the indoor temperature and humidity based on the original condition.In a conventional air conditioning system, only one single sensor is often installed at the air inlet to detect the temperature and humidity of th
14、e environment. However, due to the location of the sensor, the effective sensor range is limited to the vicinity around the air conditioning system. In order to obtain more accurate data of the environment conditions of the greenhouse, this study adopts a multi-points measuring structure to collect
15、temperature and humidity data around the greenhouse. The data from the sensors are delivered by a wireless communication system to provide more accurate data input to a more exible intelligent control system. ZigBee, bluetooth and Wi-Fi are among the most common wireless communication protocols in r
16、ecent years. The transmission range of ZigBee is tens of meters; it is more suitable for usage in middle-size greenhouses than bluetooth, and its power consumption and cost are lower than Wi-Fi 68. Therefore ZigBee is chosen as the communication protocol in the intelligent air conditioner proposed i
17、n this study. ZigBee has been successfully deployed by researchers in automatic equipments of agriculture, animal husbandry, and aquaculture.In order to control the temperature and humidity in the greenhouse with accuracy, we need to model the greenhouse environment correctly 14,15. However, it is v
18、ery difcult to construct a precise mathematical model of the environment of the microclimate of the greenhouse because it is nonlinear, time varying, and with large time delay and large hysteretic, along with some other features. Since the fuzzy theorem utilizes linguistic fuzzy variables to describ
19、e a system without constructing a precise mathematical model of the controlled system, it is particularly suited for the greenhouse environment system. This study adopts fuzzy control to compute the values of fuzzy variables of temperature and humidity16,17, deduce control strategy from control rule
20、s, and control the temperature and humidity to meet predetermined criteria. This study uses ZigBee WSN to collect temperature and humidity data in the laboratory which plays the role of a greenhouse, adopts fuzzy control as the core of the intelligent air conditioner,and uses Visual Basic software t
21、o design graphical user interface (GUI) for control, supervision and historic data browsing. Finally,the Elipse Power Studio monitoring software is used to build a monitor platform to provide off-site supervision personnel with information regarding the operation mode and environment status of the g
22、reenhouse, and to send messages such as mobile phone text to maintenance personnel to schedule maintenance or repair when an incident such as a sensor failure occurs.2. Hardware design and installation scheme2.1. Structure of the air conditionerThe air conditioner consists of one indoor unit and one
23、 outdoor unit. There are four major components in the indoor unit: compressor, condenser, expansion device, and evaporator 18. Fin tubes that act either as condenser or evaporator are included in the outdoor unit. The air conditioner operates in one of the ve operation modes: air dehumidier mode, ai
24、r heater mode, air cooler mode, blower fan mode, and automation mode. The operation mode of the air conditioner is controlled by the switching of the valves.2.1.1. Air dehumidier modeThe refrigerant ow in the air dehumidier mode is the red arrow line as shown in Fig. 1. (For interpretation of the re
25、ferences to color in this sentence, the reader is referred to the web version of the article.) High temperature and high pressure gas refrigerant ows out of the compressor, passes through the 4-way valve, and ows through the coil of the indoor condenser coil where it gives off heat, cools down, and
26、turns into liquid form. Then the refrigerant ows through the expansion device B, the indoor evaporator coil, and back into the compressor. The high pressure liquid refrigerant absorbs heat as it expands into gas form and its pressure drops along this path. The blower fan of the indoor unit forces th
27、e supply air to ow into the indoor unit and pass through the evaporator unit to cool down the air so that its temperature drops below the dew point. Thus the water vapor in the air condenses on the surface of the evaporator coil, and the function of dehumidication is accomplished. Then the air ows t
28、hrough the condenser coil and is heated up back to its original temperature as it leaves the air conditioner.Fig.12.1.2. Air heater modeThe refrigerant ow in the air heater mode is the green arrow line as shown in Fig. 1. (For interpretation of the references to color in this sentence, the reader is
29、 referred to the web version of the article.) High temperature and high pressure gas refrigerant ows out of the compressor, passes through the 4-way valve, and ows through the coil of the indoor condenser coil where it gives off heat to the supply air that passes by and turns into normal temperature
30、 and high pressure liquid form. Then the refrigerant ows through solenoid valve A and expansion device A where it releases its pressure and becomes normal temperature and low pressure liquid refrigerant. Finally the refrigerant ows through the n tubes of the outdoor unit, absorbs heat as it expands
31、into low pressure gas refrigerant, and ows back to the compressor. The n tubes play the role of an evaporator. The blower fan of the indoor unit forces the supply air to pass through the condenser coil of the indoor unit. The air is heated up, and its relative humidity is lowered.2.1.3. Air cooler m
32、odeThe refrigerant ow in the air cooler mode is the yellow arrow line as shown in Fig. 1. (For interpretation of the references to color in this sentence, the reader is referred to the web version of the article.) High temperature and high pressure gas refrigerant ows out of the compressor, passes t
33、hrough the 4-way valve, and ows through the n tubes of the outdoor unit where it gives off heat and turns into normal temperature and high pressure liquid form. The n tubes play the role of a condenser. Then the refrigerant ows through the solenoid valve C and expansion device B, releases its pressu
34、re, and turns into normal temperature and low pressure liquid form. The refrigerant then ows into the evaporator coil of the indoor unit, absorbs heat, expands into gas form, and nally ows back into the compressor. The supply air is forced by the blower fan of the indoor unit to ow the evaporator co
35、il and cools down, and its temperature drops below the dew point, thus both functions of cooling and dehumidication are accomplished.2.1.4. Blower fan modeWhen the temperature and the humidity of the controlled environment is within the desired range set in the intelligent air conditioner, only the
36、blower fan of the indoor unit operates to circulate air in the greenhouse.2.1.5. Automation modeIn the automation mode, the intelligent air conditioner automatically determines in which of the above four modes it should operate. The intelligent air conditioner receives the temperature and humidity d
37、ata from the sensors deployed in the environment, compares them with the desired values set by the user, and determines the operating mode. A fuzzy control algorithm and expert experience are adopted to perform the task.2.2. SensorsThe technical parameters of the temperature sensors and the humidity
38、 transducers of the intelligent air conditioner are shown in Table 1. There are 4 sensor nodes in the study system, three of them are ZigBee wireless sensor nodes which are evenly spaced in the laboratory and are embedded with digital humidity and temperature sensors SHT11, and the other sensor node
39、 is installed in the air inlet of the intelligent air conditioner equipped with a temperature sensor LM35 and humidity transducer HF3223.The output signal of the temperature sensor LM35 is amplied by a non-inverse amplier, and sent to the analog-to-digital converter (ADC) of the microprocessor of th
40、e fuzzy controller. Since the error of the temperature sensor is 0.25 and eight bits are utilized by the 10-bit ADC for the A/D conversion, the resolution of conversion is 0.019 V/bit.The output signal of the humidity transducer HF3223 is a periodic signal, and the humidity measured is a function of
41、 the length of the signal period. Because the power of the output signal is very low, an open-collector transistor circuit is used to amplify the signal before it is sent to the CCP (Capture/Compare/PWM) module of the microprocessor of the fuzzy controller to calculate the humidity corresponding to
42、the signal period. SensorTechnical parameterCentigrade temperature sensor(LM35)Linear + 10.0 mV/ scale factorDedicated humidity transducer(HF3223)Rated for full 55 to +150 rangeStable, linear proportional frequencyoutput from 10 to 95% RHDigital humidity and temperature sensor (SHT11)Calibrated with
43、in 5% RH 55% RHRH operating range 0100% RHTemperature operating range 40 to +125 2.3. ZigBee wireless sensor network moduleThe JN5148-EK010 19 evaluation kit for the ZigBee wireless sensor network module based on the JN5148 wireless microcontroller is used in this study. The JN5148 is an ultra low p
44、ower and high performance microcontroller targeted at ZigBee networking application.The network of this study is a star conguration. The measurements of the digital humidity and temperature sensors SHT11 are sent through the ZigBee wireless sensor nodes to the ZigBee coordinator in the network cente
45、r, and the data collected by the ZigBee coordinator are then sent via DuPont line to the Fuzzy controller for further analysis and processing.2.4. MicroprocessorThe PIC18F4520 20 microprocessor is used in this study as the core of the intelligent air conditioner. This microprocessor has two interrup
46、t vectors: high priority interrupt and low priority interrupt. The high priority interrupts are UART and INT0, and the low priority interrupts are INT1, INT2, and CCP. The priorities of the interrupts are dened by the user. When an interrupt request is issued, its priority is determined and an inter
47、rupt mission is executed depending on its interrupt ag. 3. ConclusionThis study integrates ZigBee WSN into a fuzzy controller, designs and builds an intelligent air conditioner, and successfully applies them to the temperature and humidity control of a greenhouse. The use of ZigBee WSN not only meas
48、ures the temperature and humidity closer to the real environment and enables the intelligent air conditioner to achieve desired settings more efciently, but also reduces the installation cost compared to that of conventional connected-by-wire sensors. The GUI can record the entire sensor data receiv
49、ed from the ZigBee WSN sensor nodes and the air inlet of the air conditioner, monitor the temperature and humidity at each environment node, to provide a more suitable plantation environment. The monitor platform in this study, which is built from the Elipse Power Studio monitoring software, can not only browse the internet but also send messages automatic