CN103036625A - Design method of detecting system for telecontrol remote terminal unit (RTU) and information channel - Google Patents

Abstract

A design method for telecontrol RTU and channel detection system, which confirms that the structure of RTU and channel monitoring system should be a distributed control system, that is, each substation is equipped with a front-end computer; the power dispatching center uses an industrial control computer for centralized management and control ; The CSD data communication method of the GSM system is applied to realize the two-way data communication between the on-site main control unit and the monitoring center; and the alarm information is transmitted to the mobile phone of the management personnel by means of a short message; the CPU is first initialized; Carrier frequency channel data, and then judge the fault according to relevant principles; if the system is found to be abnormal, start the GSM communication module to send the fault information to the background monitoring center. The invention has the advantages of being used for monitoring the voltage and current conditions of RTU or other equipment. With remote signaling and remote control functions, it can perform remote control operations on RTU or other equipment. The data during the operation is stored in the database for reference.

Description

Design method of a telecontrol RTU and channel detection system

technical field

The invention relates to the technical field of control systems, in particular to a design method for a telecontrol RTU and a channel detection system.

Background technique

During the operation of the substation, real-time monitoring is required by the remote power dispatching center. Upload relevant operating parameters and status information to the dispatching center through channels, optical fiber cables, etc., and send control instructions to the RTU of the substation.

However, in this operation process, it often occurs that the substation loses signal contact with the power dispatching center for some reason, and the power dispatching center cannot judge whether the RTU operation of the substation is wrong and the RTU system crashes, so that the data cannot be uploaded, or Communication failed due to channel failure. As a result, system management and safety production are affected or even accidents occur.

Contents of the invention

The purpose of the present invention is to accurately monitor the relevant equipment of the substation, and especially provides a design method of the telecontrol RTU and channel detection system.

The present invention provides a kind of telecontrol RTU and channel detection system design method, it is characterized in that: the scheme determination of described telecontrol RTU and channel detection system design method:

Confirm that the structure of the RTU and channel monitoring system should be a distributed control system, that is, each substation is equipped with a front-end computer. The power dispatching center uses an industrial control computer for centralized management and control; the following four communication methods are available:

[1] Still use the original communication channel of the substation, that is, optical cable or cable;

[2] Using the telephone communication network;

[3] Adopt wireless trunking communication network;

[4] Utilize the GSM public wireless mobile communication network;

Among the above communication methods, the first method can effectively judge the general failure of RTU and channel, but it cannot judge the simultaneous failure of RTU and channel or the high bit error rate of the channel, but it is more practical, low in cost and has no maintenance cost;

The second method is available, but it is still a wired transmission method. If the telephone line is interrupted due to external damage and natural disasters, the system will also fail to work normally.

The third way is to use the wireless cluster communication method to overcome the shortcomings of the first two methods, but it needs to establish a communication base station, and its communication distance is limited by the transmission power. Perform maintenance on communication systems.

The fourth communication method is a communication method based on the GSM public wireless mobile communication network. It does not require network maintenance and can communicate with voice, data and short messages. This communication method has the characteristics of low cost of use, unlimited communication distance, stable communication effect, and reliable data transmission. Through the comparison of the schemes, only the first and fourth communication ways are developed separately to suit the needs of different users.

System structure and working principle:

Use the telecontrol channel itself to realize the fault detection system structure as shown in Figure 1:

This device is installed on the RTU side and always monitors the receiving channel of the RTU. When the signal of the receiving channel is normal, the device is in the monitoring state and does not affect the normal communication of the RTU. When the receiving channel signal has no carrier frequency and the signal level is lower than -40DB, this device throws off the RTU sending channel, and sends the RTU status to the dispatcher using the CDT protocol. This device can collect 8 channels of RTU state quantities and 8 channels of analog quantities (0-30V), and has two channels of remote control;

Using GSM communication to realize the fault monitoring system structure: as shown in Figure 2

The whole system is composed of three parts: the front-end machine part installed on the site of each substation, the background monitoring center system and the GSM wireless public communication system;

The front-end computer completes the collection of various telemetry signals, remote signaling signals and carrier frequency signals of the substation. When an abnormal situation occurs, the relevant data is uploaded to the background monitoring center through the GSM wireless communication system, and various instructions and data transmitted from the monitoring center can also be received and related operations can be performed.

The background monitoring center receives the on-site data uploaded by the front-end computer, and can realize sound and light alarm. The working status and carrier frequency channel data of the front-end computer can be retrieved at any time, and various operation commands can be sent to the front-end computer to download relevant data.

GSM wireless mobile communication system GSM (Global Sysent Mobilecommunication) is a global mobile communication system. It is a relatively mature, perfect and most widely used system in the mobile communication system based on time-division multiple access technology. It is currently the main mode of my country's public mobile communication network. The system mainly provides voice, short message, data and other services. Based on the communication mode of data service and short message, it can be made into a data communication system for transmitting various detection, monitoring data signals and control commands. At present, it has been used in remote monitoring, positioning and navigation, personal communication terminals, etc. in the fields of military, national defense, and industry. Since our country has already established a perfect GSM public mobile communication network, the application of the above-mentioned system does not need to set up a dedicated communication network, nor does it require a large amount of system maintenance costs.

This system mainly uses the CSD data communication mode of the GSM system to realize the two-way data communication between the on-site main control unit and the monitoring center. And the alarm information is transmitted to the mobile phone of the management personnel by means of SIM short message.

Due to the adoption of GSM CSD data mode and SIM short message data communication mode, this system has the characteristics of strong real-time performance, perfect automatic data processing function, fast transmission speed, strong anti-interference ability and good compatibility.

Use the telecontrol channel itself to realize the fault detection design principle: as shown in Figure 3

The core of this device is the N80C196KB16-bit single-chip microcomputer of INTEL company. The channel management part uses the AM7910 chip to detect the quality of the channel, and uses a relay to switch the channel. The data collection part completes the collection of YC and YX data. The remote control execution part can directly act on the AC and DC power supply or the reset circuit of the RTU. The data interface part can interface with RTU or other devices to realize mutual monitoring. The display part of the panel can display the working status of RTU, channel status, YX status, etc.

Using GSM communication to realize fault detection front-end computer hardware and software design principles:

In order to meet the aforementioned technical requirements, determine the structure of the front-end machine as shown in Figure 4

The front-end machine mainly takes the single-chip microprocessor C8051F020 as the core, and expands two carrier frequency interfaces on the periphery of the single-chip microprocessor, one 12-bit telemetry signal interface with eight input ports, and one remote signal input interface with eight input ports. Two remote control switch output ports, one RS-232 serial communication interface and status indicator array.

The single-chip microprocessor C8051F020 is a fully integrated mixed-signal system-on-a-chip, fully compatible with the 8051 instruction set.

C8051F020 is a system-on-a-chip that works independently. Using C8051F020 for RTU and channel monitoring system can greatly reduce peripheral components, give full play to the high-speed characteristics of F020, and greatly improve the integration of the system.

The function of the carrier frequency channel interface is to read the converted carrier frequency channel data into the single-chip microprocessor. Two pieces of FSK modem chip AM7910 are used to realize the conversion of uplink and downlink carrier frequency data. AM7910 is a FSK modem chip specially used for low-speed serial analog channels. It is characterized by supporting CCITT V.21, V.23, Bell 103, and Bell 202 protocols, and the communication rate is 300-2400bit/s. The peripheral circuit is simple, and the use of external jumpers can realize multiple protocols, multiple rates, and multiple working modes.

Because the single-chip microprocessor C8051F020 has two serial communication interfaces UART, but one of them has been assigned to the GSM communication module. Therefore, only one serial communication interface is available for the two channels of uploading and downloading frequency. In order to meet the conversion requirements of the upper and lower frequency channels, a serial/parallel data conversion circuit is designed by using a MCS-51 series single-chip microcomputer 89C2051. In this way, one of the two carrier frequency channels uses a piece of AM7910 to directly convert the carrier frequency data and send it to a serial interface of C8051F020. Another carrier frequency channel data is converted by AM7910 and sent to the serial interface of 89C2051 microcontroller, then preprocessed by 89C2051, and converted into parallel data, and the parallel carrier frequency data is sent to the parallel interface of C8051F020. The principle diagram of the carrier frequency channel is shown in Figure 5.

For the telemetry signal interface, the highest input voltage is required to be ±30V, and the highest input voltage of the A/D converter on-chip of the C8051F020 single-chip microprocessor is +3V. As for the input voltage of +30V, a resistor divider voltage attenuation circuit is used to reduce the input voltage of +30V to +3V input. In order to measure the input voltage of -30V, an operational amplifier is designed for inverting amplification, and the input voltage of -30V is reduced to +3V input. The two circuits are designed on the same circuit board, and the positive and negative inputs are switched by a short-circuit jumper method. Using the on-chip programmable amplifier and related software, the automatic switching of 0-30V; 0-15V; 0-7.5V gears can be realized, which greatly simplifies the measurement work and improves the test accuracy. The level conversion circuit is shown in Figure 6.

In the remote signaling signal interface, a photoelectric coupler is used to isolate the input remote signaling signal from the system, reducing the impact of external interference on the system. Remote signaling interface circuit, as shown in Figure 7.

GSM communication module: GSM communication module adopts industrial communication module TC35T of Siemens Company. TC35T has four transmission modes of voice, data, short message and FAX; it works in the GSM-900MHz and 1800MHz frequency band; the working power supply is 8-30V; ; Data transmission adopts AT command set; externally provides standard RS232 interface and power interface. When applying, connect the single-chip microprocessor C8051F020 with the standard RS232 serial port chip and the serial port of TC35T directly with a cable, and then it can be used.

Before using the TC35T module, a computer must be used to initialize the TC35T offline, and store the setting parameters in the TC35T.

Since the module no longer receives other AT commands in the data communication mode, it can only perform data transmission. Therefore, it is necessary to use the "+++" command to switch from data mode to command mode.

The main program flow of the front-end computer software is shown in Figure 8. In the flowchart, the CPU is first initialized. Afterwards, telemetry, remote signaling, and carrier frequency channel data are collected separately, and then faults are identified according to relevant principles. If the system is found to be abnormal, start the GSM communication module and send the fault information to the background monitoring center.

The design method of the telecontrol RTU and channel detection system is a communication based on the GSM network which can simultaneously monitor the RTU device and the channel carrier online. The main station centrally displays the RTU uploaded data of each sub-station, judges the fault, and realizes the multi-functional monitoring system such as remote control, telemetry, and remote signaling for the sub-stations.

The design method of the telecontrol RTU and channel detection system can realize online monitoring of RTU and channels, and has the functions of fault judgment, alarm, storage, and message display, and the remote terminal has the functions of telemetry, remote signaling, remote control, and channel fault judgment , Use GSM channel to realize online monitoring of RTU and channel, for any type of telecontrol RTU and channel.

Advantages of the present invention:

The telecontrol RTU and the channel detection system design method described in the present invention are used for monitoring the voltage and current conditions of the RTU or other equipment. With remote signaling function, it is used to monitor the action status of related equipment in the substation or the related status of RTU. With remote control function, it can perform remote operation on RTU or other equipment. Monitoring the channel status includes monitoring whether the channel data is correct or not, and can read the channel data at any time for research and judgment when needed. When the remote voltage is too low or the remote signal is dislocated or the channel data is wrong, it should be reported to the monitoring center and alarmed in time. All the data in the above operation process are stored in the database for future reference.

Description of drawings

Below in conjunction with accompanying drawing and embodiment the present invention is described in further detail:

Figure 1 is a structural diagram of the fault detection system realized by using the telecontrol channel itself;

Fig. 2 is a structural diagram based on the GSM wireless public communication system;

Figure 3 is a schematic diagram of the fault detection design using the telecontrol channel itself;

Fig. 4 is a block diagram of the front-end machine system;

Fig. 5 is a schematic diagram of a carrier frequency channel;

Fig. 6 is a schematic diagram of the telemetry interface circuit;

Fig. 7 is a schematic diagram of the remote signaling interface circuit;

Fig. 8 is a flowchart of the main program of the front-end computer software.

Detailed ways

Example 1

This embodiment provides a kind of telecontrol RTU and channel detection system design method, it is characterized in that: the scheme determination of described telecontrol RTU and channel detection system design method:

Confirm that the structure of the RTU and channel monitoring system should be a distributed control system, that is, each substation is equipped with a front-end computer. The power dispatching center uses an industrial control computer for centralized management and control; the following four communication methods are available:

[1] Still use the original communication channel of the substation, that is, optical cable or cable;

[2] Using the telephone communication network;

[3] Adopt wireless trunking communication network;

[4] Utilize the GSM public wireless mobile communication network;

Among the above communication methods, the first method can effectively judge the general failure of RTU and channel, but it cannot judge the simultaneous failure of RTU and channel or the high bit error rate of the channel, but it is more practical, low in cost and has no maintenance cost;

The second method is available, but it is still a wired transmission method. If the telephone line is interrupted due to external damage and natural disasters, the system will also fail to work normally.

The third way is to use the wireless cluster communication method to overcome the shortcomings of the first two methods, but it needs to establish a communication base station, and its communication distance is limited by the transmission power. Perform maintenance on communication systems.

The fourth communication method is a communication method based on the GSM public wireless mobile communication network. It does not require network maintenance and can communicate with voice, data and short messages. This communication method has the characteristics of low cost of use, unlimited communication distance, stable communication effect, and reliable data transmission. Through the comparison of the schemes, only the first and fourth communication ways are developed separately to suit the needs of different users.

System structure and working principle:

Use the telecontrol channel itself to realize the fault detection system structure as shown in Figure 1:

This device is installed on the RTU side and always monitors the receiving channel of the RTU. When the signal of the receiving channel is normal, the device is in the monitoring state and does not affect the normal communication of the RTU. When the receiving channel signal has no carrier frequency and the signal level is lower than -40DB, this device throws off the RTU sending channel, and sends the RTU status to the dispatcher using the CDT protocol. This device can collect 8 channels of RTU state quantities and 8 channels of analog quantities (0-30V), and has two channels of remote control;

Using GSM communication to realize the fault monitoring system structure: as shown in Figure 2

The whole system is composed of three parts: the front-end machine part installed on the site of each substation, the background monitoring center system and the GSM wireless public communication system;

The front-end computer completes the collection of various telemetry signals, remote signaling signals and carrier frequency signals of the substation. When an abnormal situation occurs, the relevant data is uploaded to the background monitoring center through the GSM wireless communication system, and various instructions and data transmitted from the monitoring center can also be received and related operations can be performed.

The background monitoring center receives the on-site data uploaded by the front-end computer, and can realize sound and light alarm. The working status and carrier frequency channel data of the front-end computer can be retrieved at any time, and various operation commands can be sent to the front-end computer to download relevant data.

GSM wireless mobile communication system GSM (Global Sysent Mobilecommunication) is a global mobile communication system. It is a relatively mature, perfect and most widely used system in the mobile communication system based on time-division multiple access technology. It is currently the main mode of my country's public mobile communication network. The system mainly provides voice, short message, data and other services. Based on the communication mode of data service and short message, it can be made into a data communication system for transmitting various detection, monitoring data signals and control commands. At present, it has been used in remote monitoring, positioning and navigation, personal communication terminals, etc. in the fields of military, national defense, and industry. Since our country has already established a perfect GSM public mobile communication network, the application of the above-mentioned system does not need to set up a dedicated communication network, nor does it require a large amount of system maintenance costs.

This system mainly uses the CSD data communication mode of the GSM system to realize the two-way data communication between the on-site main control unit and the monitoring center. And the alarm information is transmitted to the mobile phone of the management personnel by means of SIM short message.

Due to the adoption of GSM CSD data mode and SIM short message data communication mode, this system has the characteristics of strong real-time performance, perfect automatic data processing function, fast transmission speed, strong anti-interference ability and good compatibility.

Use the telecontrol channel itself to realize the fault detection design principle: as shown in Figure 3

The core of this device is the N80C196KB16-bit single-chip microcomputer of INTEL company. The channel management part uses the AM7910 chip to detect the quality of the channel, and uses a relay to switch the channel. The data collection part completes the collection of YC and YX data. The remote control execution part can directly act on the AC and DC power supply or the reset circuit of the RTU. The data interface part can interface with RTU or other devices to realize mutual monitoring. The display part of the panel can display the working status of RTU, channel status, YX status, etc.

Using GSM communication to realize fault detection front-end computer hardware and software design principles:

In order to meet the aforementioned technical requirements, determine the structure of the front-end machine as shown in Figure 4

The front-end machine mainly takes the single-chip microprocessor C8051F020 as the core, and expands two carrier frequency interfaces on the periphery of the single-chip microprocessor, one 12-bit telemetry signal interface with eight input ports, and one remote signal input interface with eight input ports. Two remote control switch output ports, one RS-232 serial communication interface and status indicator array.

The single-chip microprocessor C8051F020 is a fully integrated mixed-signal system-on-a-chip, fully compatible with the 8051 instruction set.

C8051F020 is a system-on-a-chip that works independently. Using C8051F020 for RTU and channel monitoring system can greatly reduce peripheral components, give full play to the high-speed characteristics of F020, and greatly improve the integration of the system.

The function of the carrier frequency channel interface is to read the converted carrier frequency channel data into the single-chip microprocessor. Two pieces of FSK modem chip AM7910 are used to realize the conversion of uplink and downlink carrier frequency data. AM7910 is a FSK modem chip specially used for low-speed serial analog channels. It is characterized by supporting CCITT V.21, V.23, Bell 103, and Bell 202 protocols, and the communication rate is 300-2400bit/s. The peripheral circuit is simple, and the use of external jumpers can realize multiple protocols, multiple rates, and multiple working modes.

Because the single-chip microprocessor C8051F020 has two serial communication interfaces UART, but one of them has been assigned to the GSM communication module. Therefore, only one serial communication interface is available for the two channels of uploading and downloading frequency. In order to meet the conversion requirements of the upper and lower frequency channels, a serial/parallel data conversion circuit is designed by using a MCS-51 series single-chip microcomputer 89C2051. In this way, one of the two carrier frequency channels uses a piece of AM7910 to directly convert the carrier frequency data and send it to a serial interface of C8051F020. Another carrier frequency channel data is converted by AM7910 and sent to the serial interface of 89C2051 microcontroller, then preprocessed by 89C2051, and converted into parallel data, and the parallel carrier frequency data is sent to the parallel interface of C8051F020. The principle diagram of the carrier frequency channel is shown in Figure 5.

For the telemetry signal interface, the highest input voltage is required to be ±30V, and the highest input voltage of the A/D converter on-chip of the C8051F020 single-chip microprocessor is +3V. As for the input voltage of +30V, a resistor divider voltage attenuation circuit is used to reduce the input voltage of +30V to +3V input. In order to measure the input voltage of -30V, an operational amplifier is designed for inverting amplification, and the input voltage of -30V is reduced to +3V input. The two circuits are designed on the same circuit board, and the positive and negative inputs are switched by a short-circuit jumper method. Using the on-chip programmable amplifier and related software, the automatic switching of 0-30V; 0-15V; 0-7.5V gears can be realized, which greatly simplifies the measurement work and improves the test accuracy. The level conversion circuit is shown in Figure 6.

In the remote signaling signal interface, a photoelectric coupler is used to isolate the input remote signaling signal from the system, reducing the impact of external interference on the system. Remote signaling interface circuit, as shown in Figure 7.

GSM communication module: GSM communication module adopts industrial communication module TC35T of Siemens Company. TC35T has four transmission modes of voice, data, short message and FAX; it works in the GSM-900MHz and 1800MHz frequency band; the working power supply is 8-30V; ; Data transmission adopts AT command set; externally provides standard RS232 interface and power interface. When applying, connect the single-chip microprocessor C8051F020 with the standard RS232 serial port chip and the serial port of TC35T directly with a cable, and then it can be used.

Before using the TC35T module, a computer must be used to initialize the TC35T offline, and store the setting parameters in the TC35T.

Since the module no longer receives other AT commands in the data communication mode, it can only perform data transmission. Therefore, it is necessary to use the "+++" command to switch from data mode to command mode.

The main program flow of the front-end computer software is shown in Figure 8. In the flowchart, the CPU is first initialized. Afterwards, telemetry, remote signaling, and carrier frequency channel data are collected separately, and then faults are identified according to relevant principles. If the system is found to be abnormal, start the GSM communication module and send the fault information to the background monitoring center.

The design method of the telecontrol RTU and channel detection system is a communication based on the GSM network which can simultaneously monitor the RTU device and the channel carrier online. The main station centrally displays the RTU uploaded data of each sub-station, judges the fault, and realizes the multi-functional monitoring system such as remote control, telemetry, and remote signaling for the sub-stations.

The design method of the telecontrol RTU and channel detection system can realize online monitoring of RTU and channels, and has the functions of fault judgment, alarm, storage, and message display, and the remote terminal has the functions of telemetry, remote signaling, remote control, and channel fault judgment , Use GSM channel to realize online monitoring of RTU and channel, for any type of telecontrol RTU and channel.

Claims (3)

1. a telecontrol RTU and channel detection system design method, is characterized in that: the scheme determination of described telecontrol RTU and channel detection system design method: Confirm that the structure of the RTU and channel monitoring system should be a distributed control system, that is, each substation is equipped with a front-end computer; the power dispatching center uses an industrial control computer for centralized management and control; the following four communication methods are available: [1] Still use the original communication channel of the substation, that is, optical cable or cable; [2] Using the telephone communication network; [3] Adopt wireless trunking communication network; [4] Utilize the GSM public wireless mobile communication network; Among the above communication methods, the first method can effectively judge the general failure of RTU and channel, but it cannot judge the simultaneous failure of RTU and channel or the high bit error rate of the channel, but it is more practical, low in cost and has no maintenance cost; The second method is available, but it is still a wired transmission method. If the telephone line is interrupted due to external damage or natural disasters, the system will also fail to work normally; The third way is to use the wireless cluster communication method to overcome the shortcomings of the first two methods, but it needs to establish a communication base station, and its communication distance is limited by the transmission power. maintenance of communication systems; The fourth communication method is a communication method based on the GSM public wireless mobile communication network. It does not require network maintenance and can communicate with voice, data and short messages. This communication method has low usage costs and unlimited communication distance. The communication effect is stable, the data transmission is reliable, etc.; through the comparison of the schemes, only the first and fourth communication methods are developed separately to meet the needs of different users; System structure and working principle: Use the telecontrol channel itself to realize the fault detection system structure, install it at the RTU end, and always monitor the receiving channel of the RTU. When the receiving channel signal is normal, the device is in the monitoring state, which does not affect the normal communication of the RTU; when the receiving channel signal has no carrier frequency When the signal level is lower than -40DB, this device throws off the RTU sending channel, and uses the CDT protocol to send the RTU status to the dispatcher; this device can collect 8-way RTU state quantities and 8-way analog quantities (0-30V) , and has two remote control; Using GSM communication to realize the structure of the fault monitoring system: the whole system consists of three parts: the front-end machine part installed on the site of each substation, the background monitoring center system and the GSM wireless public communication system; The front-end computer completes the collection of various telemetry signals, remote signaling signals and carrier frequency signals of the substation; when an abnormal situation occurs, the relevant data is uploaded to the background monitoring center through the GSM wireless communication system, and various information transmitted from the monitoring center can also be received. Various instructions and data and related operations; The background monitoring center receives the on-site data uploaded by the front-end computer, and can realize sound and light alarm; it can retrieve the working status and carrier frequency channel data of the front-end computer at any time, send various operation commands to the front-end computer, and download relevant data; This system mainly uses the CSD data communication method of the GSM system to realize the two-way data communication between the on-site main control unit and the monitoring center; and transmits the alarm information to the mobile phone of the management personnel by means of SIM short message; Due to the adoption of GSM CSD data mode and SIM short message data communication mode, this system has the characteristics of strong real-time performance, perfect automatic data processing function, fast transmission speed, strong anti-interference ability, and good compatibility; Use the telecontrol channel itself to realize the design principle of fault detection: use INTEL's N80C196KB16-bit single-chip microcomputer, the channel management part uses the AM7910 chip to detect the quality of the channel, and uses a relay to switch the channel; the data acquisition part completes the collection of YC and YX data ;The remote control execution part can directly act on the AC and DC power supply or reset circuit of the RTU; the data interface part can interface with the RTU or other devices to realize mutual monitoring; the panel display part can display the working status, channel status, YX status, etc. of the RTU; Utilize GSM communication to realize fault detection front-end machine hardware and software design principles: In order to meet the aforementioned technical requirements, the structure of the front-end machine is determined: the front-end machine mainly takes the single-chip microprocessor C8051F020 as the core, and expands two on the periphery of the single-chip microprocessor. Carrier frequency interface, one 12-bit telemetry signal interface with eight input ports, one remote signal input interface with eight input ports; two remote control switch output ports, one RS-232 serial communication interface and status indicator array; The single-chip microprocessor C8051F020 is a fully integrated mixed-signal system-on-chip, fully compatible with the 8051 instruction set; Devices, give full play to the high-speed characteristics of F020, greatly improving the integration of the system; The function of the carrier frequency channel interface is to read the carrier frequency channel data into the single-chip microprocessor after conversion; two FSK modem chips AM7910 are used to realize the conversion of uplink and downlink carrier frequency data; AM7910 is a dedicated low-speed FSK modem chip for serial analog channel, which is characterized by supporting CCITT V.21, V.23, Bell103, Bell202 protocol, communication rate 300-2400bit/s; Because the single-chip microprocessor C8051F020 has two serial communication interfaces UART, but one of them has been assigned to the GSM communication module; therefore, only one serial communication interface is available for the two channels of uploading and downloading frequency; in order to meet the above For the conversion requirements of the download frequency channel, a serial/parallel data conversion circuit is designed by using a MCS-51 series microcontroller 89C2051; in this way, one of the two carrier frequency channels uses a piece of AM7910 to directly convert the carrier frequency data, And send it to a serial interface of C8051F020; another carrier frequency channel data is sent to the serial interface of 89C2051 single-chip microcomputer after being converted by AM7910, and then preprocessed by 89C2051, and converted into parallel data, and the parallel carrier frequency data is sent to into the parallel interface of C8051F020; For the telemetry signal interface, the maximum input voltage is required to be ±30V, while the maximum input voltage of the on-chip A/D converter of the C8051F020 single-chip microprocessor is +3V; for the input voltage of +30V, a resistor divider attenuation circuit is used to The input voltage of +30V is reduced to +3V input; in order to measure the input voltage of -30V, an operational amplifier is designed for inverting amplification, and the input voltage of -30V is reduced to +3V input; the two circuits are designed on the same circuit board, using Short-circuit jumper method to switch positive and negative input; using on-chip programmable amplifier and related software, automatic switching of 0-30V; 0-15V; 0-7.5V gear can be realized, which greatly simplifies the measurement work and improves the test precision; In the remote signaling signal interface, a photoelectric coupler is used to isolate the input remote signaling signal from the system, reducing the impact of external interference on the system; GSM communication module: GSM communication module adopts industrial communication module TC35T of Siemens; TC35T has four transmission modes of voice, data, short message and FAX; it works in GSM-900MHz and 1800MHz frequency range; working power supply is 8-30V; baud The rate is 300bps-115kbps, and the automatic baud rate is set at 1200bps-115kbps; the data transmission adopts the AT command set; the standard RS232 interface and power interface are provided externally; the single-chip microprocessor C8051F020 is equipped with a standard RS232 serial port during application The chip is directly connected to the serial port of TC35T with a cable, and it can be used; Before using the TC35T module, a computer must be used to initialize the TC35T offline, and store the setting parameters in the TC35T; Since the module no longer receives other AT commands in the data communication mode, it can only perform data transmission; therefore, it is necessary to use the "+++" command to switch from the data mode to the command mode; In the flow chart, the CPU is first initialized; after that, telemetry, remote signaling, and carrier frequency channel data are collected respectively, and then fault identification is carried out according to relevant principles; if any abnormality is found in the system, the GSM communication module is started to send the fault information to the background monitoring center. 2. according to the telecontrol RTU described in claim 1 and channel detection system design method, it is characterized in that: described telecontrol RTU and channel detection system design method, can carry out a kind of monitoring to RTU device and channel carrier online simultaneously Based on GSM network communication; the main station centrally displays the RTU uploaded data of each sub-station, judges the fault, and realizes the multi-functional monitoring system such as remote control, telemetry, and remote signaling for the sub-stations. 3. according to the telecontrol RTU described in claim 1 and channel detection system design method, it is characterized in that: described telecontrol RTU and channel detection system design method, can realize the on-line monitoring to RTU and channel, have fault judgment, Alarm, storage, and message display functions. The remote terminal has the functions of telemetry, remote signaling, remote control, and channel fault judgment. It uses the GSM channel to realize online monitoring of RTU and channel, and is used for any type of telecontrol RTU and channel.

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