The Research Of Measurable Heating System Based On Meter-bus

Nowadays,it is generally used to charge by the construction area in winter heating,which limits the people's awareness of energy conservation greatly.Compared with foreign developed countries in terms of energy saving,the average energy consumption in China is 2-3 times that of the countries with similar climate,the waste is very prominent.In European and the North American heating developed countries,there are many kinds of heating metering methods,such as heat meter method,on-off time and area method,heat allocator method,etc.In this subject,the principle of ultrasonic heat meter and the method of automatic data collection are researched in detail,to design a system of heating measurement and data acquisition,which can work automatically.In this subject includes two parts: ultrasonic heat meter and data collector,based on the meter-bus.The electrical characteristics and physical layer of the meter-bus are investigated in detail.On the basis of simulation by the multisim software,the design of host and slave of the meter-bus are completed,to prepare for communication by the meter-bus.Firstly,the ultrasonic heat meter based on time-difference ultrasonic is designed.By comparing the advantages and disadvantages of various tube structures,the reflective tube structure on the middle axis is designed.The method of measuring the time of ultrasonic propagation is investigated in detail.In order to meet the requirements of measurement accuracy,a special ti me-to-digital chip is used.The temperature measurement method is investigated in detail.In order to meet the demand of low power consumption,the capacitance charging and discharging method is used.In the specific design,the TDC-GP21 chip is used to measure the flow velocity and temperature,and the precision of the designed meter reaches the mainstream level in the industry.Then,the data collector based on the u C/OS II operating system is designed.The data collector is the core device to upload the heat meter data to the remote data center.It can automatically read the data of heat meter,and upload the data to the data center automatically.In order to establish a data transmission network on sundry occasions,adopts the GPRS wireless network on the data collector.In this design,the FATFS file system is used to manage all of the data.Finally,the test result of the ultrasonic heat meter and the data collector are introduced.The ultrasonic heat meter can work stably,and the test results conform to the national 2 level standard.In the design of the data collector,the performance of the meter-bus host module is excellent,and static load capacity of the host module can reach 300 m A.The GPRS wireless network is implemented successfully.The data of heat meter is successfully collected,and the data is uploaded to the data center through the GPRS network accurately.