High-speed optical fiber longitudinal differential protection data transmission circuit

Abstract

The utility model discloses a high-speed optical fiber longitudinal differential protection data transmission circuit, which belongs to the technical field of power system relay protection and comprises an optical fiber longitudinal differential protection MCU (microprogrammed control unit), an optical module, an Ethernet MAC (media access control) layer and an Ethernet physical layer, the Ethernet MAC layer and the Ethernet physical layer are connected with each other, and the optical fiber longitudinal differential protection MCU is in communication connection with a user-defined data protocol processor. The optical fiber longitudinal differential protection MCU is connected with the Ethernet MAC layer, and the Ethernet physical layer is connected with the optical module. The optical fiber longitudinal differential protection device has the advantages of being simple in circuit and high in transmission rate, has the advantages of being low in cost, high in communication rate, simple in circuit, easy to configure and the like, can improve the reliability of a longitudinal differential protection program, and guarantees the real-time performance of optical fiber longitudinal differential data transmission.

Description

TECHNICAL FIELD

[0001] The utility model mainly relates to the electric power system relay protection technical field, concretely is a kind of high-speed optical fiber longitudinal differential protection data transmission circuit. BACKGROUND

[0002] Optical fiber longitudinal differential protection is mainly to utilize optical fiber channel fast transmission line opposite real-time protection data to this side, and the side utilizes Kirchhoff's current law to calculate a kind of line fault fast judgment protection element.Optical fiber longitudinal differential protection constitutes and is shown in Fig. Figure 1 The key of protection element is to utilize optical fiber channel fast transmission protection data.The content of channel transmission is mainly the sampling value of three-phase current, zero-sequence current or the real part or imaginary part of its phasor, in addition, it also contains some state quantity, command quantity, synchronization information, CRC code and other contents.The sensitivity and rapidity of protection element action depend on the transmission speed of optical fiber longitudinal differential protection data.Simple, fast and reliable transmission method is particularly important.

[0003] At present, there are mainly two kinds of optical fiber differential protection data transmission in the market: one is to utilize 2M ultra-low speed optical module to connect directly transmission protection data through TTL (Transistor-Transistor Logic) level and UART (Universal Asynchronous Receiver Transmitter) receiving and transmitting feet of optical fiber longitudinal differential protection MCU (Micro Control Unit), as shown in Fig. Figure 2 The advantage is that the circuit is simple, and the disadvantages are that 1. the electrical signal is not modulated, which is easy to cause optical saturation; 2. the data transmission rate is lower than 2M, which cannot transmit a large amount of data signals in real time; 3. the transmission delay is large, which causes problems in data synchronization of reference side protection and synchronous side; two, the sending end utilizes programmable device FPGA (Field Programmable Gate Array) or CPLD (Complex Programmable Logic Device) to convert the electrical signal into a signal suitable for transmission in optical fiber through coding, level conversion, serial-parallel conversion and other conversion links. The receiving end utilizes FPGA (Field Programmable Gate Array) or CPLD (Complex Programmable Logic Device) to convert the signal into data that can be recognized by optical fiber longitudinal differential protection MCU (Micro Control Unit) through decoding, level conversion and parallel-serial conversion; the receiving and transmitting processing signal structure is shown in Fig. Figure 3 The advantage is that high-speed optical fiber longitudinal differential data transmission can be realized. The disadvantages are that the circuit is complex, the cost is high, and the FPGA (Field Programmable Gate Array) needs to be programmed using hardware language, which has a high implementation threshold. UTILITY MODEL CONTENT

[0004] The utility model discloses technical scheme provides a kind of high-speed optical fiber longitudinal differential protection data transmission circuit, to solve the technical problem that the optical fiber longitudinal differential protection data transmission mode cannot have the advantages of simple circuit and fast transmission rate in the background technology.

[0005] The utility model discloses technical scheme provides a kind of high-speed optical fiber longitudinal differential protection data transmission circuit, to solve the technical problem that the optical fiber longitudinal differential protection data transmission mode cannot have the advantages of simple circuit and fast transmission rate in the background technology.

[0006] A kind of high-speed optical fiber longitudinal differential protection data transmission circuit, including optical fiber longitudinal differential protection MCU and optical module, further include the Ethernet MAC layer and Ethernet physical layer connected with each other, the optical fiber longitudinal differential protection MCU is connected with custom data protocol processor communication, the optical fiber longitudinal differential protection MCU is connected with Ethernet MAC layer, and the Ethernet physical layer is connected with optical module.

[0007] As a kind of implementation, the optical fiber longitudinal differential protection MCU itself has Ethernet MAC layer, the Ethernet physical layer is borne in the Ethernet chip containing only physical layer, and optical fiber longitudinal differential protection MCU is connected by MII interface and Ethernet physical chip.

[0008] As a second implementation, the optical fiber longitudinal differential protection MCU itself does not have Ethernet MAC layer, but has Ethernet interface, the Ethernet MAC layer and Ethernet physical layer are borne in the Ethernet chip of SPI interface MAC layer and physical layer integration;Optical fiber longitudinal differential protection MCU is connected by SPI interface and Ethernet chip.

[0009] As a third implementation, the optical fiber longitudinal differential protection MCU itself does not have Ethernet interface;The Ethernet MAC layer and Ethernet physical layer are borne in the Ethernet chip of MAC layer and physical layer integration of support FMC bus;Optical fiber longitudinal differential protection MCU is connected by FMC bus port and Ethernet chip.

[0010] Specifically, the data packet of custom data protocol includes sending end address, receiving end address, sending length, sending point number, receiving point number, sending time, channel delay, transmission data and frame check sequence, sending end address occupies 1 byte, receiving end address occupies 1 byte, sending length occupies 2 bytes, sending point number occupies 1 byte, receiving point number occupies 1 byte, sending time occupies 2 bytes, channel delay occupies 2 bytes, transmission data occupies 24-1024 bytes, and frame check sequence is generated by Ethernet MAC layer check.

[0011] Specifically, the Ethernet MAC layer is used to realize the frame check sequence of data;

[0012] And / or, the Ethernet physical layer device is integrated with all conversion modules between electrical signal and optical signal inside.

[0013] Specifically, in the working state, the Ethernet chip is set to the optical port mode and the transceiving mode.

[0014] Compared with the prior art, the utility model has the advantages of:

[0015] The utility model discloses a point-to-point data transmission feature is mainly realized to the optical fiber longitudinal differential protection, discards the complex communication protocol in the Ethernet, utilizes the Ethernet chip, and the high -speed transmission of optical fiber protection data is realized through the Ethernet PHY (physical layer) and MAC (media access control) layer plus self -defining data protocol. Specifically, the utility model discloses the transmission of Ethernet chip, and the high -speed transmission in the optical fiber after the physical layer modulation of electric signal through the Ethernet chip. Transmission rate can reach 100M or 1000M, and the current Figure 2 The transmission mode can not real -time transmission mass signal, and the transmission delay big shortcoming. The Ethernet chip is low in price, and can realize configuration through the register, and the use is convenient, and the Figure 3 The transmission mode circuit copy, the shortcoming of high price, configuration complexity. Then the utility model is simple and reliable, and the Figure 2 The corresponding transmission mode circuit is simple and Figure 3 The corresponding transmission mode transmission rate is fast.

[0016] The utility model discloses a optical fiber longitudinal differential protection MCU and PHY (physical layer) chip and MAC (media access control) chip interface are easy, and reliable high -speed conversion of electric signal to optical signal can be realized through simple peripheral interface circuit. The Ethernet chip physical layer is integrated with all conversion modules between electric signal and optical signal, and only needs simple configuration to use. Thus can avoid the external complex synchronization, handshake protocol, avoids the drive of optical fiber transceiver module, 4B / 5B coding, and the design of parallel data to serial data conversion circuit. Utilize the MAC layer of Ethernet to realize the FCS (frame check sequence) of data, reduces the data check of longitudinal differential protection program to receiving program, improves the reliability of longitudinal differential protection program.

[0017] The utility model discloses a optical fiber longitudinal differential protection's feature, adopts self -defining data protocol, avoids the complex protocol in the Ethernet protocol for network communication, thereby making the design of system more simple, more easily guaranteeing the real -time of optical fiber longitudinal differential data transmission.

[0018] Summarizing, the utility model has the advantages of low cost, high communication rate, simple circuit, easy configuration and the like.

[0019] The utility model will be explained in detail in the following with the specific embodiment and the accompanying drawing. DRAWINGS

[0020] Figure 1A schematic diagram of a fiber optic longitudinal differential protection in the prior art is shown in Figure 1.

[0021] Figure 2 A schematic diagram of a 2M ultra-low speed optical port and MCU interface transmission mode in the prior art is shown in Figure 2.

[0022] Figure 3 A schematic diagram of an FPGA processing signal transmission mode in the prior art is shown in Figure 3.

[0023] Figure 4 A schematic diagram of the present application in Embodiment One is shown in Figure 4.

[0024] Figure 5 A schematic diagram of the present application in Embodiment Two is shown in Figure 5.

[0025] Figure 6 A schematic diagram of the present application in Embodiment Three is shown in Figure 6.

[0026] Figure 7 A flow chart of the specific process of transmitting and receiving data in the present application is shown in Figure 7. DETAILED DESCRIPTION

[0027] In order to facilitate the understanding of the present application, the present application will be described more fully below with reference to the accompanying drawings, in which several embodiments of the present application are given. However, the present application can be realized in different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present application more thorough and comprehensive.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs. The terminology used in the description of the present application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0029] Embodiment One: Please refer to the accompanying drawings Figure 4 A high-speed fiber optic longitudinal differential protection data transmission circuit, comprising:

[0030] The fiber optic longitudinal differential protection MCU (micro control unit) itself has an Ethernet MAC (media access control) layer, which is used to manage the sending and receiving of data frames and encapsulate data processed by the custom data protocol processor into Ethernet frames or extract data of the custom data protocol from the received Ethernet frames; the fiber optic longitudinal differential protection MCU communicates with the custom data protocol processor;

[0031] Ethernet chip, only contains physical layer, used to convert Ethernet frame into a signal suitable for transmission on the optical fiber, and the signal received from the optical fiber into Ethernet frame; MCU (micro control unit) through MII (media independent interface) and Ethernet chip physical layer connection, optical fiber differential protection MCU (micro control unit) through MII (media independent interface) interface transmission data;

[0032] Optical module, used to convert electrical signals into optical signals, and convert optical signals into electrical signals, the optical module is connected with Ethernet physical layer device;

[0033] Custom data protocol processor, used to define the format and rules of data transmission; custom data protocol data packet consists of table 1 content, sender address occupies 1 byte, receiver address occupies 1 byte, sending length occupies 2 bytes, sending point number occupies 1 byte, receiving point number occupies 1 byte, sending time occupies 2 bytes, channel delay occupies 2 bytes, transmission data occupies 24-1024 bytes, and FCS (frame check sequence) is generated by MAC (media access control) layer check. Refer to the attached Figure 1 The reference side and the synchronous side of the optical fiber longitudinal differential protection are connected through the optical fiber to transmit the custom data protocol data packet, realize high-speed data interaction, realize the synchronization of the sampling data of the reference side and the synchronous side, and further realize the monitoring and protection of the line fault.

[0034] Table 1 custom data protocol data packet content

[0035] Example two: the difference between this embodiment and example one is:

[0036] Please refer to the attached Figure 5 The optical fiber longitudinal differential protection MCU (micro control unit) itself does not have Ethernet MAC (media access control) layer, but has Ethernet interface; select SPI (serial peripheral) interface MAC (media access control) layer and PHY (physical) layer integrated chip; MCU (micro control unit) is connected with Ethernet chip through SPI (serial peripheral) interface and transmits and reads data through SPI port.

[0037] The others are the same as example one.

[0038] Example three: the difference between this embodiment and example one is:

[0039] Please refer to the attached Figure 6The optical fiber longitudinal differential protection MCU (micro control unit) itself does not have an Ethernet interface; a MAC (media access control) layer and a PHY (physical layer) integrated chip supporting an FMC (Flexible Memory Controller) bus is selected; the optical fiber longitudinal differential protection MCU (micro control unit) is connected with the Ethernet chip through an FMC (Flexible Memory Controller) bus port and transmits data through the FMC (Flexible Memory Controller) bus.

[0040] Other embodiments are the same as embodiment one.

[0041] The specific process of data receiving and sending in the utility model is shown in Figure 7 After power on, the Ethernet chip is first initialized and set, then the Ethernet chip is set to work in the optical port (fiber interface) mode, and then the Ethernet is set to the receiving and sending mode. When the optical fiber longitudinal differential protection MCU (micro control unit) needs to send data, the sending time is recorded in the data packet, and the data is sent through the DMA (direct memory access) mode. When the data is received, the optical fiber longitudinal differential protection MCU (micro control unit) interface is interrupted, and the interrupt time is recorded. When there is receiving and sending error, the Ethernet chip is restarted through the RESET (reset) pin for reset.

[0042] The three connection modes provided in embodiments one to three are simple and reliable, and can take into account Figure 2 the advantages of simple circuit and Figure 3 fast transmission rate of corresponding transmission mode, and can avoid Figure 2 , Figure 3 the defects of optical fiber differential protection data transmission shown in the description. Since the utility model uses an Ethernet chip for transmission, the electrical signal is modulated by the physical layer of the Ethernet chip and transmitted at high speed in the optical fiber. The transmission rate can reach 100M or 1000M. The defects of current Figure 2 transmission mode, such as inability to transmit a large amount of signals in real time and large transmission delay, can be effectively solved. The Ethernet chip is low in price and can be configured through a register, which is convenient to use, and effectively solves the defects of Figure 3 transmission mode, such as circuit duplication, high price and complex configuration.

[0043] The utility model has been described above in conjunction with the drawings, and obviously the specific implementation of the utility model is not limited by the above mode, as long as the method concept and technical solution of the utility model are adopted for this non-essential improvement, or the concept and technical solution of the utility model is directly applied to other occasions without improvement, which is within the protection scope of the utility model.

Claims

1. A high-speed fiber optic longitudinal differential protection data transmission circuit, comprising a fiber optic longitudinal differential protection MCU and an optical module, characterized in that: Further comprising an interconnected Ethernet MAC layer and an Ethernet physical layer, the fiber longitudinal differential protection MCU is in communication connection with a self-defined data protocol processor, the fiber longitudinal differential protection MCU is connected with the Ethernet MAC layer, and the Ethernet physical layer is connected with an optical module.

2. The high-speed fiber optic current differential protection data transmission circuit of claim 1, wherein: The fiber longitudinal differential protection MCU itself has an Ethernet MAC layer, and the Ethernet physical layer is borne in an Ethernet chip containing only a physical layer, and the fiber longitudinal differential protection MCU is connected with the Ethernet physical chip through an MII interface.

3. The high-speed fiber optic current differential protection data transmission circuit of claim 1, wherein: The fiber longitudinal differential protection MCU itself does not have an Ethernet MAC layer, but has an Ethernet interface, the Ethernet MAC layer and the Ethernet physical layer are borne in an Ethernet chip with an integrated SPI interface MAC layer and physical layer, and the fiber longitudinal differential protection MCU is connected with the Ethernet chip through an SPI interface.

4. The high-speed fiber optic current differential protection data transmission circuit of claim 1, wherein: The fiber longitudinal differential protection MCU itself does not have an Ethernet interface, the Ethernet MAC layer and the Ethernet physical layer are borne in an Ethernet chip supporting an FMC bus, and the fiber longitudinal differential protection MCU is connected with the Ethernet chip through an FMC bus port.

5. A high-speed fiber optic current differential protection data transmission circuit according to any one of claims 2-4, characterized in that: The data packet of the self-defined data protocol comprises a sending end address, a receiving end address, a sending length, a sending point number, a receiving point number, a sending time, a channel delay, transmission data and a frame check sequence, the sending end address occupies 1 byte, the receiving end address occupies 1 byte, the sending length occupies 2 bytes, the sending point number occupies 1 byte, the receiving point number occupies 1 byte, the sending time occupies 2 bytes, the channel delay occupies 2 bytes, the transmission data occupies 24-1024 bytes, and the frame check sequence is generated through the Ethernet MAC layer.

6. A high-speed fiber optic current differential protection data transmission circuit according to any one of claims 2-4, characterized in that: The Ethernet MAC layer is used for realizing frame check sequence of data; And / or, the Ethernet physical layer device internally integrates all conversion modules between electrical signals and optical signals.

7. A high-speed fiber optic current differential protection data transmission circuit according to any one of claims 2-4, characterized in that: In the working state, the Ethernet chip is set as an optical port mode and a transceiving mode.

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