Street lamp management is a high-tech and difficult task in urban management. With the increase in the number of street lighting facilities, the drawbacks of traditional manual management are becoming more and more obvious. (1) It consumes a lot of manpower and material resources, and greatly increases the management cost; (2) It cannot realize the monitoring of the running condition of the street lamp facilities, resulting in the lag of the facility failure information, and cannot be maintained in time, affecting the safety of citizens at night. There are many potential safety hazards; (3) When the power supply situation of the power grid changes, the feed power of the street lamp facility cannot be controlled in real time with the change of the grid voltage, resulting in a large amount of energy waste, reducing the use efficiency of the electric energy and shortening the service life of the lamp. . Along with the rapid development of digital technology and network technology, people have researched the digitalization and network management of street lighting systems, which not only can save energy and extend the service life of lamps, but also improve the management level of urban construction and guarantee. The safety of citizens traveling at night reduces the incidence of traffic accidents.
With the improvement of people's living standards, the monitoring of public street lights has become more and more important after years of research and practice, although the current domestic street lamp monitoring system has reached a certain level in terms of functions, technical performance and work reliability.
However, there are still many shortcomings in the regulation and areas for improvement. Intelligent, networked, real-time, precise and dynamic have become the inevitable trend of the development of modern urban road lighting management system.
1 system model design and system communication mechanism 1 system model design Intelligent street lamp monitoring system mainly consists of monitoring center, intelligent street lamp controller and fund project: Shandong Province technical innovation project intelligent power saving technology (200891907009).
Research and development of the direction of automatic control technology.
It consists of a street light node. The monitoring center PC centrally manages the operation of the entire streetlight monitoring system, including remote real-time control, system operation information collection and monitoring. The intelligent street light controller is responsible for intelligent lighting control, analysis and execution management center instructions and collection and reporting operation data of the road sections under its jurisdiction. The street light node is responsible for the control and status detection of a single street light. GPRS is used for data transmission between the intelligent street lamp controller and the monitoring center, and power line carrier communication is used for data transmission between the street lamp node and the intelligent street lamp controller. The system model is as shown: system model First, through the collection of illumination, the intelligent street lamp controller determines whether the street lighting system (made up of tens or even hundreds of street lamps in a street) needs to be turned on, and if it needs to run, the power is required. The switch unit is used to complete the soft start of the street light. After the street lamp is turned on, the acoustic sensor installed on the road surface collects the acoustic signal emitted by the vehicle flow and the human flow, and the intelligent street lamp controller issues control information, and the power switch unit controls the contactless transformer to determine the output voltage of the street lamp. If the real-time vehicle and human traffic are large, the illumination needs to be high, and the system automatically increases the output voltage of the street lamp according to the demand; on the contrary, the system automatically reduces the output voltage of the street lamp.
1.2 System Communication Mechanism Each slave in the system is assigned a unique slave address. When the host communicates with the slave, the host first calls a slave address, wakes up the called slave, and performs data exchange between the master and slave. The slaves that are not called continue their work. The MCU controls the correct reception of address and data signals by setting and resetting the multi-machine communication control bit SM2. When the data is returned, the data or address is distinguished by setting TB8 to 0 or 1.
The communication protocol stipulates: (1) The MCU communicates in Mode 3, the address frame is indicated by 1, and the data frame is represented by 0; (2) The baud rate of communication is set (3) Address frame 01H~FFH, representing the slave Address; (4) 00H is a control command that is sent to all slaves in the form of an address frame, and commands each slave to resume SM2=1 and wait for the receiving state.
2 system hardware design 21 intelligent street lamp controller hardware is mainly composed of sound sensor, photoelectric sensor, signal amplifier, V / F converter, microcontroller, trigger circuit and switch circuit.
The optical signal is converted into an electrical signal by the photoelectric sensor, and the electrical signal is amplified, A/D converted, and sent to the microprocessor to control the switch of the street lamp. The sound signal is converted into a voltage signal by the sound sensor, and the voltage signal is sent to the A/D analog-to-digital converter through the amplifier, and the voltage signal is converted into a frequency pulse signal, and different frequency pulse data is obtained according to the sound size, and sent to the micro After the processor, through a series of calculations and analysis, the control signal can be obtained, and then the data is sent to the D/A digital-to-analog converter to be converted into an analog signal, which is sent to the trigger circuit, and finally the trigger circuit drives the power switch unit. By controlling the turn-off of the switch unit, the controlled object can obtain the corresponding voltage, and its hardware structure diagram is as shown.
21.1 Microprocessor This system uses the AT89S52 single-chip microcomputer. The AT89S52 is a low-power, high-performance 8-bit CMOS microcontroller with 8k bytes of flash programmable/erase read-only memory. , non-volatile storage technology manufacturing. The FPEROM on the chip allows the program memory to be reprogrammed online or with a general purpose nonvolatile memory programmer.
AT89S52 single-chip microcomputer is stable in high temperature environment. It supports online programming ISP. It does not need a dedicated programmer to facilitate debugging. It provides an efficient and flexible solution for many embedded control applications. Its role is to drive the connection between GPRS module and external network. Receive and process the data packet uploaded by the GPRS module, assemble or generate the data packet to be transmitted to the GPRS module control relay to open and close, and calculate the collected data.
2 is the connection port of the A/D conversion circuit, P13, P15, P17 are the connection ports of the D/A conversion circuit, P1 4 is the interface of the sound sensor, and P16 is the interface of the light sensor.
The GPRS module of the 212GPRS wireless communication module system uses the wireless data transmission module MC35i of Siemens to support data, SMS, voice and fax services. The MC35i is a next-generation GSM/GPRS dual-mode module that is fully compatible with the previous generation of the MC35 and TC35i. The compact design provides users with a simple, in-line wireless GPRS connection. The MC35i's GPRS permanent online feature provides the fastest data transfer rate.
The MC35i module has 40 pins that are routed through a ZIF (ZeroInsertionFor) connector. These 40 pins can be divided into five categories, namely power supply, data input/output, SIM card, audio interface and control. The first to the 14th feet are the power supply part: 1~5 is the power supply voltage input terminal VBATT+, 6~10 is the power supply ground GND, 11 and 12 are the charging pins, 13 is the external output voltage (for the external circuit), 14 is the ACCU TEMP is a thermistor with a negative temperature coefficient. 24~29 card pins, and the other I is CCIN, CCRST, CCIO, CCCLK, CCVCC and CCGND.33~40 are voice interfaces, used to connect the phone handle. 15, 30 , 31 and 32 feet for the control part: 15 is the ignition line IGT (Ignition) When the TC35i is powered on, it must be given to the IGT - a module with a low level greater than 100ms is started; 30 is RTCbackup), the module is controlled by the AT command. The AT command can be used to realize the setting of module parameters to realize the transmission and reception of data. The peripheral electrical diagram is as shown.
After the hardware connection is completed, before the GPRS Internet operation, the GPRS module must first be set. The main setting work has the following 38400 commands, the baud rate is set to 384001/s or other suitable baud rate, and the default communication speed setting mobile terminal class is B, that is, monitoring multiple services at the same time; Only one type of service can be run, that is, only GPRS can be used at the same time, or GSM voice communication can be used.
To activate the GPRS function, if it returns OK, the GPRS connection is successful; if it returns ERROR, it means that GPRS fails. At this time, it should be checked whether the GPRS service of the S1M card has been opened, whether the GPRS module antenna is correctly installed, etc. The 2 street lamp node street lamp node mainly completes the sending, power-off control and line state detection functions of the street lamp line, and at the same time ensures remote control. In the special case of failure, it can be switched to the manual control mode for manual control, and a manual control/automatic control switch button is added. Its control signal is given by the microprocessor and the feedback control result is returned to the microprocessor. At the same time, the collected voltage, current, power consumption, accumulated power consumption, power factor, and undervoltage and overvoltage detection results are uploaded. The current and power information is also used as auxiliary information for cable condition monitoring.
3 system software design system software mainly includes two parts: (1) data acquisition and transmission part, is the AT89S52 single-chip computer as the core program design; (2) monitoring center management software design part. The monitoring center data management interface uses VB6 0 programming, and the program of the single-chip microcomputer in the intelligent street lamp controller is based on the KE1L development platform written in C51 language. This can shorten the development cycle, reduce the development cost, make the program easy to debug and maintain, high reliability, readability and portability. 1 Intelligent street lamp controller software design The main task of the control software is system initialization, timing signal Sampling, analysis of the sampling results and output of control signals.
31.1 Main program The program initialization includes initialization of the timer and counter, and initialization of the D/A digital-to-analog converter. The function is to determine the working mode, input control word and load data. The acquisition switch for the sound data by the timer interrupt program is collected by the data acquisition subroutine and sent to the data processing subroutine. After processing, the control signal is output, and the main program is notified after the delay. The main program flow chart is as shown.
31.2 Communication Protocol The host first issues a set of reading commands. The intelligent street lamp controller sends the collected data back to the host, and can also set the field parameters. The data communication protocol is as follows: I controller address I hair length I function code I data field ILRC check I end code I, where the function code mainly includes: 03H (read save register), 06H (preset single register), 10H ( Preset multiple registers); the data field is mainly composed of the data register address, the number of registers and the register preset data.
31.3 Fuzzy Control Algorithm Intelligent control is the door edge science, which uses the logical thinking of human beings to control objects. The types of control of intelligent control include hierarchical hierarchical intelligent control, expert control, neural network control and fuzzy control. After analysis, the system selects fuzzy control and gives a specific algorithm based on the actual situation.
According to the working condition of the street lamp system, the fuzzy control has three linguistic variables: noise input variable deviation E, noise deviation change rate EC and output control quantity U, wherein the noise input variable deviation is divided into large (PB), large (PS), Medium (Z) and 5 levels represent the whole situation of on-site noise; the rate of change of noise deviation is also divided into five cases, namely, strong rate of change (PB), strong (PS), medium (Z), and weaker ( NS), weak (NB). Each linguistic variable is represented by 5 language values: negative NB = "2 negative small NS = "1, zero Z = 0, positive small PS = l positive large PB = 2 output control quantity U is the same as E and EC , for 5 levels range. Therefore, its control rule table can use the following relationship: Nearly 2 monitoring center software design The host communication interface of this system is written by VB6 0 communication control MSComm, MSComm control has perfect function of serial port data transmission and reception, and good human-machine interface. . The communication terminal software includes receiving and collecting data, transmitting control commands, parameter settings, and the like, and operating in the form of an interface.
Table 1 Test results Average voltage (V) Average current (A) Total electricity measurement time Non-power saving state 1 month Power saving state 1 month Power saving rate 5 Conclusion GPRS-based intelligent street light monitoring system integrates advanced automatic stabilization Pressure technology, environmental integrated intelligent control technology, computer technology and wireless communication technology have greatly improved the street lamp management level and service quality, and realized the concept of reasonable lighting, beautifying lighting and safe lighting. After field testing, the system has less harmonic content and high power saving rate, achieving multiple effects such as intelligent power saving and extended lamp life. Therefore, the use of the system to transform the traditional street lamp management system is a method with less investment, quick effect and high efficiency, which is worth promoting.
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