CN201868845U

CN201868845U - Optical longitudinal differential protection device

Info

Publication number: CN201868845U
Application number: CN2010206436613U
Authority: CN
Inventors: 王成修
Original assignee: SHANGHAI SUNRISE POWER AUTOMATION CO Ltd
Current assignee: Shanghai Sunrise Power Technology Co., Ltd.
Priority date: 2010-12-06
Filing date: 2010-12-06
Publication date: 2011-06-15
Anticipated expiration: 2020-12-06

Abstract

An optical longitudinal differential protection device relates to the field of communication technology, and solves the technical problems that the hardware cost is lowered and the software design is simplified. The device comprises a CPU (Central Processing Unit) and an FGPA (Field Programmable Gate Array), wherein the FGPA is internally provided with a signal modulation module, a signal demodulation module, an FIFO (First In First Out) transmitting module, an FIFO receiving module, a data frame coding module, a data frame decoding module, a parallel-to-serial conversion module and a serial-to-parallel conversion module; the input end of the FIFO transmitting module and the output end of the FIFO receiving module are respectively connected with a parallel communication port of the CPU; the output end of the FIFO transmitting module sequentially connects the data frame coding module and the parallel-to-serial conversion module with the input end of the signal modulation module; and the output end of the signal demodulation module sequentially connects the serial-to-parallel conversion module and the data frame decoding module with the input end of the FIFO receiving module. The device provided by the utility model has low hardware cost and simple software design.

Description

A kind of equipment for protecting optical fibre longitudinal difference

Technical field

The utility model relates to the communication technology, particularly relates to a kind of technology of equipment for protecting optical fibre longitudinal difference.

Background technology

Relaying protection is the important leverage of power system safety and stability operation; and the development of Fibre Optical Communication Technology makes optical fiber obtain application more and more widely in relaying protection, is that the Current Differential Protection of medium just is being subjected to more and more paying close attention to and applying because of the incomparable various advantages of other protection forms are arranged with optical fiber.

The optical-fiber longitudinal difference protection of electric power system is by the optical fiber communication interaction data by two protective devices that are in diverse location; and realize sampling realize longitudinal difference protection synchronously; must adopt synchronous communication between two protective devices, and both sides can extract information lock in time easily in data flow.

As shown in Figure 2; the existing fiber longitudinal differential protecting equipment is all by the CPU(central processing unit), synchronous serial chip, FPGA(programmable gate array) form; in FPGA, be built-in with signal modulation module and signal demodulation module; the input of the output of signal modulation module and signal demodulation module is connected to optical fiber transport channel through interface conversion circuit; utilize the synchronous serial chip to realize the transmitting-receiving and the encoding and decoding of data, utilize FPGA that serial data is carried out the signal modulation and demodulation and make its suitable Optical Fiber Transmission.The mode that the synchronous serial chip that the existing fiber longitudinal differential protecting equipment adopts adds FPGA has the high defective of hardware cost; and the synchronous serial chip is encoded to data according to the HDLC agreement; when coding, need utilize opening flag and closing the location that flag realizes frame head and postamble of HDLC agreement; because its form of opening flag and pass flag is " 01111110 "; for guaranteeing to open flag; close the uniqueness of flag; therefore when digital coding except; close and just insert one " 0 " in other outer data of flag whenever to 5 continuous " 1 " automatically; when data decode except; close in other outer data of flag and just delete one " 0 " automatically to 5 continuous " 1 " whenever; but because the data of transmission are real-time change; make the number of in Frame, inserting " 0 " also change; and then make that it also is uncertain adopting the Frame length of this coding method; make that the required time of every frame data transmission is also different; therefore must carry out frame head identification when data frame transfer earlier realizes synchronously; and then time-delay reading of data; its software processes process more complicated, software design is cumbersome.

The utility model content

At the defective that exists in the above-mentioned prior art, it is low that technical problem to be solved in the utility model provides a kind of hardware cost, the simple equipment for protecting optical fibre longitudinal difference of software design.

In order to solve the problems of the technologies described above, a kind of equipment for protecting optical fibre longitudinal difference provided by the utility model, comprise CPU and FPGA, described CPU is provided with the parallel communications mouth, be built-in with the signal modulation module that is used for serial signal is modulated to fiber-optic signal among the described FPGA, and be used for fiber-optic signal is demodulated into the signal demodulation module of serial signal, each is connected to optical fiber transport channel through interface conversion circuit the input of the output of described signal modulation module and signal demodulation module, it is characterized in that: also be built-in with the transmission fifo module among the described FPGA, receive fifo module, the Frame coding module, the Frame decoder module, parallel serial conversion module, string and modular converter;

The output of the input of described transmission fifo module and reception fifo module is connected respectively to the parallel communications mouth of CPU;

The output of described transmission fifo module connects Frame coding module, the parallel serial conversion module input to the signal modulation module successively;

The output of described signal demodulation module connects string successively, and also modular converter, Frame decoder module arrive the input that receives fifo module.

The equipment for protecting optical fibre longitudinal difference that the utility model provides; use single FPGA to substitute the combination that original synchronous serial interface chip adds FPGA; energy economize on hardware cost; and adopted 10 " 0 " as frame head; adopted 1 " 1 " as the boundary mark will between the byte; and fill complete " 1 " to the room between the packet afterbody as bell idles at check code; therefore what the data content that no matter sends is; total energy guarantees the uniqueness of frame head; and say for specific should being used for; the data volume of its transmission is certain; therefore the length and the transmission time of whole Frame are also fixed; apply for the read operation of CPU after receiving terminal can finish receiving whole Frame again, can simplify software design.

Description of drawings

Fig. 1 is the structured flowchart of the equipment for protecting optical fibre longitudinal difference of the utility model embodiment;

Fig. 2 is the structured flowchart of existing fiber longitudinal differential protecting equipment.

Embodiment

Below in conjunction with description of drawings embodiment of the present utility model is described in further detail, but present embodiment is not limited to the utility model, every employing analog structure of the present utility model and similar variation thereof all should be listed protection range of the present utility model in.

As shown in Figure 1, a kind of equipment for protecting optical fibre longitudinal difference that the utility model embodiment is provided, comprise the CPU(central processing unit) and the FPGA(programmable gate array), described CPU is provided with the parallel communications mouth, be built-in with the signal modulation module that is used for serial signal is modulated to fiber-optic signal among the described FPGA, and be used for fiber-optic signal is demodulated into the signal demodulation module of serial signal, each is connected to optical fiber transport channel through interface conversion circuit the input of the output of described signal modulation module and signal demodulation module, it is characterized in that: also be built-in with among the described FPGA and send the FIFO(first in first out) module, receive the FIFO(first in first out) module, the Frame coding module, the Frame decoder module, parallel serial conversion module, string and modular converter;

The synchronized communication method of the equipment for protecting optical fibre longitudinal difference that the utility model embodiment is provided is characterized in that, in advance length of data package is made as fixed length, and with the format setting of packet is:

Frame head+Frame+check code+bell idles;

Wherein, frame head is 10 " 0 ", inserts one " 1 " between frame head and the Frame as boundary mark will, inserts one " 1 " after each byte in the Frame as boundary mark will, and check code is the CRC(cyclic redundancy) check code, bell idles is complete " 1 ";

When sending data, CPU sends into data to be sent earlier and sends in the fifo module, send one again and send order to sending fifo module, send and send the data to the Frame coding module after fifo module is received the transmission order, the Frame coding module according to default data packet length and form to the data of the receiving packing of encoding, and the packet after will encoding sends to parallel serial conversion module, parallel serial conversion module sends to the signal modulation module after the packet of receiving is converted to serial signal, and the signal modulation module sends to optical fiber transport channel by interface conversion circuit after serial signal is modulated to fiber-optic signal;

When receiving data, fiber-optic signal in the optical fiber transport channel is sent to the signal demodulation module by interface conversion circuit, the signal demodulation module sends to string and modular converter after fiber-optic signal is demodulated into serial signal, string and modular converter send the Frame decoder module after serial signal is converted to the parallel data bag, the Frame decoder module is decoded to the data of receiving according to default data packet length and form, decoded data are sent into and are received in the fifo module, after reception fifo module reception data finish, by sending interrupt mode notice CPU, the reading of data from receive fifo module of having no progeny during CPU receives.

Claims

1. equipment for protecting optical fibre longitudinal difference, comprise CPU and FPGA, described CPU is provided with the parallel communications mouth, be built-in with the signal modulation module that is used for serial signal is modulated to fiber-optic signal among the described FPGA, and be used for fiber-optic signal is demodulated into the signal demodulation module of serial signal, each is connected to optical fiber transport channel through interface conversion circuit the input of the output of described signal modulation module and signal demodulation module, it is characterized in that: also be built-in with the transmission fifo module among the described FPGA, receive fifo module, the Frame coding module, the Frame decoder module, parallel serial conversion module, string and modular converter;