A method and system for calibrating communication delay across a power safety zone

Abstract

This invention discloses a communication delay calibration method and system for traversing a power safety zone. The method includes: Step 1, devices in Zone I and Zone III each set their local RTC clocks to the same time base, and device I simultaneously sends an electrical pulse to device III; Step 2, after receiving the electrical pulse, device III quickly records the millisecond-level difference Δt1 between its local RTC clock time and the time base; Step 3, after waiting for a certain period of time, device I sends a time-stamped data packet of its current RTC clock to device III through a network communication interface; Step 4, after receiving the time-stamped data packet, device III quickly unpacks it and records the difference Δt2 between its local RTC clock time and the time-stamped data packet; Step 5, device III's time synchronization program calculates |Δt2-Δt1| to obtain the difference and performs communication delay calibration. This invention can conveniently and quickly detect communication time errors between physically isolated safety zones in a power secondary system.

Description

Technical Field

[0001] This invention belongs to the field of power system technology, specifically relating to a communication delay calibration method and system for traversing power safety areas. Background Technology

[0002] Security zoning is the structural foundation of the security protection system for power secondary systems. Application systems based on computer and network technologies within power generation, grid, and power supply companies are, in principle, divided into a production control zone and a management information zone (also known as Security Zone III). The production control zone can be further divided into a control zone (also known as Security Zone I) and a non-control zone (also known as Security Zone II). According to power network protection requirements, all data flows from the production control zone must be physically isolated before entering Security Zone III. That is, real-time data flowing out of the production control zone must pass through forward physical isolation equipment, and internal network information and data can only be transmitted unidirectionally.

[0003] In the process of cross-zone unidirectional data transmission, by sending the synchronized system time of Zone I as a data packet to Zone III via UDP, and then receiving it in Zone III and converting it back to the original time stamp, the time of Zone I and Zone III can be made basically consistent, achieving the effect of cross-zone time synchronization. In practice, because the physical isolation device itself is not a direct connection, the time synchronization data packet sent from Zone I will still have a certain delay when it arrives in Zone III, resulting in a certain error between the actual time the device in Zone III receives the data and the time stamp encapsulated in the data packet. It is generally considered that when this error is within 5 milliseconds, it can be considered consistent. However, currently there is a lack of convenient and rapid calibration methods for this error. How to conveniently and quickly test whether the data transmission error of the communication line through the forward isolation device is within the allowable range is a problem that existing technology needs to solve. Summary of the Invention

[0004] The purpose of this invention is to provide a communication delay calibration method for traversing a power safety zone, which solves the technical problem that existing technologies make it difficult to conveniently and quickly detect communication time errors between physically isolated safety zones in a power secondary system, i.e., difficult to perform communication delay calibration.

[0005] The communication delay calibration method for crossing a power safety zone includes the following steps:

[0006] Step 1: Both the device in Zone I and the device in Zone III set their local RTC clocks to the same time base, and the device in Zone I simultaneously sends an electrical pulse to the device in Zone III.

[0007] Step 2: After receiving the electrical pulse, the equipment in Zone III quickly records the millisecond-level difference Δt1 between the local RTC clock time and the time base, thus completing the pulse electrical signal calibration.

[0008] Step 3: After waiting for a certain period of time, the device in Zone I sends a time stamp data packet of the current RTC clock to the device in Zone III through the network communication interface. The time stamp data packet arrives at the device in Zone III after passing through the forward isolation device.

[0009] Step 4: After receiving the time stamp data packet, the equipment in Zone III quickly unpacks it, records the difference Δt2 between the local RTC clock time and the time stamp, and completes the data communication verification.

[0010] Step 5: The time synchronization program of the equipment in Zone III calculates |Δt2-Δt1| to obtain the difference, and the communication delay can be calibrated based on this difference.

[0011] Preferably, in step one, the transmitting chip with built-in embedded program emits an electrical pulse, and in step two, a fast-response circuit triggers the rapid recording of the millisecond-level difference Δt1.

[0012] Preferably, in step two, when the receiving pin of the fast response circuit receives a pulse signal, it immediately triggers the circuit to react on the rising edge and records the time difference between the current RTC clock value inside the III zone device and the time base.

[0013] Preferably, in step three, the Zone I device encapsulates the current millisecond-level time into a time stamp data packet of no more than 8 bytes and sends it to the Zone III device via the UDP network communication protocol.

[0014] Preferably, before communication delay calibration, two communication terminal devices with built-in RTC clocks are set up. The communication terminal devices are respectively located in Zone I and Zone III, corresponding to the control area and management information area. The Zone I device is equipped with a transmitting chip for sending pulse electrical signals, and the Zone III device is equipped with a fast response circuit triggered by receiving pulse electrical signals. The network communication interface of the Zone I device is connected to the network communication interface of the Zone III device through a forward isolation device, and the transmitting pin of the transmitting chip is directly connected to the receiving pin of the fast response circuit through a wire.

[0015] To apply the aforementioned communication delay calibration method, this invention also provides a communication delay calibration system that traverses a power safety zone, comprising a forward physical isolation device, a Zone I device, and a Zone III device. The Zone I device is a communication terminal device located in the control zone, and the Zone III device is a communication terminal device located in the management information zone. Both communication terminal devices are equipped with a precise internal RTC clock. The Zone I device contains a transmitting chip capable of sending pulse electrical signals, and the Zone III device contains a fast-response circuit capable of receiving pulse electrical signals. The fast-response circuit is directly signal-connected to the transmitting chip. The network communication interface of the Zone I device is connected to the network communication interface of the Zone III device via the forward isolation device.

[0016] Preferably, the receiving pin of the fast response circuit is directly connected to the transmitting pin of the transmitting chip via a wire; the forward isolation device is connected to the network communication interfaces of the Zone I device and the Zone III device via a network cable.

[0017] Preferably, the communication terminal device is a time synchronization gateway device, and all of them are programmable embedded devices that can have their hardware time set by the built-in program.

[0018] This invention has the following advantages: This method can be used to verify the internal and external times of a large management information area through actual experiments, testing whether the data transmission error is within the allowable range. Utilizing the near-zero transmission delay of pulse electrical signals via direct wire connection, pulse electrical signals are transmitted directly while time-stamped data packets are being transmitted through a forward isolation device. Comparing the time difference between the two transmission processes accurately calibrates the delay of network signals transmitted through the forward isolation device, solving the problem of the lack of a convenient and quick method for testing communication line data transmission delay errors in existing technologies. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of a communication delay calibration method for crossing a power safety zone according to the present invention. Detailed Implementation

[0020] The following detailed description of the embodiments, with reference to the accompanying drawings, will further illustrate the specific implementation of the present invention, in order to help those skilled in the art to have a more complete, accurate, and thorough understanding of the inventive concept and technical solutions of the present invention.

[0021] like Figure 1 As shown, the present invention provides a communication delay calibration method for crossing a power safety zone.

[0022] Before communication delay calibration, two communication terminal devices with built-in RTC (Real-Time Clock) clocks are set up. The communication terminal devices are respectively located in Zone I and Zone III in the control area and management information area. Zone I device is equipped with a transmitting chip that sends pulse electrical signals, and Zone III device is equipped with a fast response circuit that is triggered by receiving pulse electrical signals. The network communication interface of Zone I device is connected to the network communication interface of Zone III device through a positive isolation device. The transmitting pin of the transmitting chip is directly connected to the receiving pin of the fast response circuit through a wire.

[0023] In this embodiment, the communication terminal device is a time synchronization gateway device. The network communication port between the two time synchronization gateway devices is separated by a forward isolation device. The two devices in the two areas agree on a certain time value, hereinafter referred to as the time base (e.g., 00:00:00:00 on January 1, 2020), and it is built into their respective programs.

[0024] After completing the device connection preparation, the communication delay calibration method provided by the present invention includes the following steps.

[0025] Step 1: The device in Zone I sets its own RTC clock to the time base, and simultaneously, the transmitter chip with the built-in embedded program sends an electrical pulse to the device in Zone III. The device in Zone III also sets its own RTC clock to the same time base at the same time. Generally, the operators in both zones agree on how to set the device's RTC clock, and the time base setting is initiated simultaneously.

[0026] Step 2: After receiving the electrical pulse, the device in Zone III triggers a fast-response circuit and quickly records the millisecond-level difference Δt1 between its local RTC clock time and the aforementioned time base, completing the pulse electrical signal calibration. Since the signal timing is performed through a direct connection between the transmitting chip and the fast-response circuit, the delay of this pulse electrical signal can be considered close to 0.

[0027] Step 3: After waiting for a certain period of time (usually several seconds), the device in Zone I sends a time stamp data packet of the current RTC clock to the device in Zone III through the network communication interface. The time stamp data packet arrives at the device in Zone III after passing through the forward isolation device.

[0028] Step 4: After receiving the time stamp data packet, the embedded program of the Zone III device quickly unpacks it, records the difference Δt2 between the local RTC clock time and the time stamp, and completes the data communication verification.

[0029] Step 5: The time synchronization procedure for Zone III devices calculates |Δt2-Δt1| to obtain the difference. This difference is equivalent to the total time spent by Zone I devices in a series of processes involving cross-zone time synchronization, including communication packetization, network protocol communication, switching of the forward isolation device to allow the time stamp data packet to traverse, and unpacking by Zone III devices. In other words, it represents the time delay in the time synchronization data packet sent from Zone I reaching Zone III. Communication delay calibration can be performed based on this difference.

[0030] Corresponding to the above-mentioned communication delay calibration method, the present invention also provides a corresponding communication delay calibration system for crossing power safety areas, including a forward physical isolation device, a network cable, a conductor, a Zone I device and a Zone III device. The Zone I device is a communication terminal device set in the control area, and the Zone III device is a communication terminal device set in the management information area. Both communication terminal devices are equipped with a precise internal RTC time source (i.e., RTC clock). The RTC clock can self-time. Both communication terminal devices can be time synchronization gateway devices, both of which are programmable embedded devices that can have their hardware time set by the built-in program.

[0031] The device in Zone I contains a transmitting chip capable of sending pulsed electrical signals, which can be triggered by an internal embedded program. The transmitting pin of the transmitting chip is directly connected to the receiving pin of the fast-response circuit via a wire. The device in Zone III contains a fast-response circuit that can be triggered by receiving pulsed electrical signals. When the receiving pin of the fast-response circuit receives a pulsed electrical signal, it immediately triggers the circuit to react on the rising edge (0→1) and records the time difference between the current RTC clock value inside the device in Zone III and the time base. The transmitting pin of the transmitting chip is directly connected to the receiving pin of the fast-response circuit via a wire.

[0032] The Zone I device has a network communication interface, which can encapsulate the current millisecond-level time into a time-stamped data packet of no more than 8 bytes and send it to the Zone III device via the UDP network communication protocol. The Zone III device also has a network communication interface connected to the forward isolation device, used to receive the time-stamped data packet sent from the Zone I device via the forward isolation device. The Zone III device is also used to unpack the time-stamped data packet to obtain the time-stamped data.

[0033] The present invention has been described above by way of example with reference to the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any non-substantial improvements made using the inventive concept and technical solution of the present invention, or the direct application of the inventive concept and technical solution of the present invention to other occasions without modification, are all within the protection scope of the present invention.

Claims

1. A method for calibrating communication delay across a power safety zone, characterized in that: Includes the following steps: Step 1: Both the device in Zone I and the device in Zone III set their local RTC clocks to the same time base, and the device in Zone I simultaneously sends an electrical pulse to the device in Zone III. Step 2: After receiving the electrical pulse, the equipment in Zone III quickly records the millisecond-level difference Δt1 between the local RTC clock time and the time base, thus completing the pulse electrical signal calibration. Step 3: After waiting for a certain period of time, the device in Zone I sends a time stamp data packet of the current RTC clock to the device in Zone III through the network communication interface. The time stamp data packet arrives at the device in Zone III after passing through the forward isolation device. Step 4: After receiving the time stamp data packet, the equipment in Zone III quickly unpacks it, records the difference Δt2 between the local RTC clock time and the time stamp, and completes the data communication verification. Step 5: The time synchronization program of the equipment in Zone III calculates |Δt2 - Δt1| to obtain the difference, and the communication delay can be calibrated based on this difference.

2. The communication delay calibration method for crossing a power safety zone according to claim 1, characterized in that: In step one, an electrical pulse is emitted by a transmitter chip with a built-in embedded program, and in step two, a fast-response circuit triggers the rapid recording of the millisecond-level difference Δt1.

3. The communication delay calibration method for crossing a power safety zone according to claim 2, characterized in that: In step two, when the receiving pin of the fast response circuit receives a pulse signal, it immediately triggers the circuit to react on the rising edge and records the time difference between the current RTC clock value inside the device in zone III and the time base.

4. A communication delay calibration method for traversing a power safety zone according to claim 1, 2, or 3, characterized in that: In step three, the Zone I device encapsulates the current millisecond-level time into a time stamp data packet of no more than 8 bytes and sends it to the Zone III device via the UDP network communication protocol through the forward isolation device.

5. The communication delay calibration method for crossing a power safety zone according to claim 4, characterized in that: Before communication delay calibration, two communication terminal devices with built-in RTC clocks are set up. These communication terminal devices are respectively located in Zone I and Zone III of the control area and management information area. The Zone I device is equipped with a transmitting chip that sends pulse electrical signals, and the Zone III device is equipped with a fast response circuit that is triggered by receiving pulse electrical signals. The network communication interface of the Zone I device is connected to the network communication interface of the Zone III device through a forward isolation device. The transmitting pin of the transmitting chip is directly connected to the receiving pin of the fast response circuit through a wire.

6. A communication delay calibration system for crossing a power safety zone, based on the communication delay calibration method for crossing a power safety zone as described in claim 1, characterized in that: It includes a forward isolation device, a Zone I device, and a Zone III device. The Zone I device is a communication terminal device located in the control area, and the Zone III device is a communication terminal device located in the management information area. Both communication terminal devices are equipped with a precise internal RTC clock. The Zone I device is equipped with a transmitter chip that can send pulse electrical signals, and the Zone III device is equipped with a fast response circuit that can receive pulse electrical signals and trigger them. The fast response circuit is directly connected to the transmitter chip. The network communication interface of the Zone I device is connected to the network communication interface of the Zone III device through the forward isolation device.

7. A communication delay calibration system for traversing a power safety zone according to claim 6, characterized in that: The receiving pin of the fast response circuit is directly connected to the transmitting pin of the transmitting chip via a wire; the forward isolation device is connected to the network communication interfaces of the Zone I device and the Zone III device via a network cable.

8. A communication delay calibration system for traversing a power safety zone according to claim 7, characterized in that: The communication terminal devices are time synchronization gateway devices, and all of them are programmable embedded devices whose hardware time can be set by the built-in program.

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