CN114462180A

CN114462180A - Design based on improved Linux system station terminal

Info

Publication number: CN114462180A
Application number: CN202011244324.1A
Authority: CN
Inventors: 韩国良; 熊少义
Original assignee: Beijing Hezong Science & Technology Co ltd
Current assignee: Beijing Hezong Science & Technology Co ltd
Priority date: 2020-11-10
Filing date: 2020-11-10
Publication date: 2022-05-10

Abstract

The design mainly relates to the optimization of the implementation process of the station terminal, the improvement of efficiency and the improvement of compatibility. The device is composed of the following modules: the system comprises a main processing unit (a core board and a main control board), a sampling control unit (a sampling board and a control output board), a permanent magnet mechanism control unit and a human-computer interaction unit (a display panel), wherein each station terminal comprises the core board, four sampling boards (64 channel telemetering), two control output boards (16-channel remote control) and three control input boards (96 remote signaling). The main control board processes the remote measuring, remote signaling and remote control signals in real time, and achieves the purposes of monitoring, protecting, fault detecting and fault isolating.

Description

Design based on improved Linux system station terminal

Technical Field

The invention relates to the field of power distribution network automation, in particular to a design of a practical power distribution terminal based on an improved Linux system.

Background

In the traditional station terminal design and manufacturing process, a multi-CPU cooperative mode is usually adopted for processing, the main control CPU, the telemetry board CPU, the telecommand board CPU and the display board CPU are mainly arranged, namely the main control CPU is responsible for processing functions such as protocols, protection logics, fixed values and the like, the telemetry board CPU is responsible for sampling and calculating effective values, the telecommand board CPU is responsible for monitoring and uploading telecommand data, and the display board is responsible for displaying data processing and fixed value modification.

Because each telemetering plate is provided with an independent CPU, data synchronization between the telemetering plates has a large error, so that the power precision does not reach the standard, for example, the tenth loop power is calculated by adopting the voltage acquired by the first telemetering plate and the current acquired by the second telemetering plate, and the precision of power, energy consumption and power factor cannot meet the requirement due to the asynchronous sampling of two different sampling plates.

The remote communication board CPU reports the input signal of the remote communication board, the system requires 2ms for remote communication resolution, and the time scale of the displacement time event of the remote communication of the system is accurate to millisecond level, so that the remote communication board card needs to be calibrated with the main control board CPU by microsecond level and needs to be stored in power failure, the requirements of storage of the remote communication board card and data stored in power failure of hardware are increased, and the design complexity is improved.

The rated current of a station terminal is usually 1A or 5A, and the sampling resistor in the circuit design can be determined only by knowing the rated current of an order in advance in the production process, so that great troubles are brought to production and stock, and even the resistor is attached by mistake.

The panel is processed using the variables of the CPU and then displayed. However, due to different use occasions, the requirements for the display screens are different, so that each different display screen needs to perform corresponding different data processing, which brings great difficulty to development and production.

Because the display screen CPU needs to interact with the main control CPU, the main control CPU needs to interact with the remote signaling board CPU, the main control CPU needs to interact with debugging software, the main control CPU needs to interact with the background main station, and the main control CPU needs to interact with the cascade equipment, the complex and multi-CPU cooperation brings great difficulty to development, the requirement on the number of developers is high, and the requirement on the interaction rule is accurate and strict.

Disclosure of Invention

In order to solve the defects of the prior art, the scheme provides the station terminal which is simple in structure, convenient to develop and applicable to multiple high-efficiency occasions.

The technical scheme adopted by the invention for solving the technical problems is as follows:

a design based on an improved Linux system station terminal is characterized in that: the device is composed of the following modules: the system comprises a main processing unit (a core board and a main control board), a sampling control unit (a sampling board and a control output board), a permanent magnet mechanism control unit and a human-computer interaction unit (a display panel), wherein each station terminal comprises the core board, four sampling boards (64 channel telemetering), two control output boards (16-channel remote control) and three control input boards (96 remote signaling). The main control board processes the remote measuring, remote signaling and remote control signals in real time, and achieves the purposes of monitoring, protecting, fault detecting and fault isolating.

As a preferred embodiment of the present invention, the main processing unit (core board + main control board) is responsible for acquisition of telemetry data, scanning of telemetry data, transmission and fault judgment of remote control instructions, protocol implementation, fault recording, flexible protocol configuration, software remote update, fixed value remote download, and other functions, the sampling control unit (sampling board + control output board) does not have an independent CPU, the main control performs real-time sampling by an improved Linux system, synchronous sampling requirements can be achieved for different telemetry boards, and finally microsecond-level delay errors can be achieved by software calibration, which is close to real values to a great extent, and power, energy consumption, and power factors can also meet precision requirements.

As the preferred embodiment of the invention, the change of the remote signaling is directly transmitted to the main control CPU by hardware, and the time error of the occurrence moment does not exist, so the microsecond precision can be realized on the resolution and the remote signaling anti-shake, and the requirement of a power grid is met. The remote communication board does not need to be synchronous with a CPU clock, save timestamps and the like, so that the design is greatly simplified, and the design cost is reduced.

As a preferred embodiment of the invention, the rated current of a station terminal is usually 1A or 5A, and the device switches the sampling resistor through a hardware simulation switch component, so that the rated current can be selected through software, thereby reducing the probability of errors in the production process and greatly reducing the risk brought by errors in the production process.

As a preferred embodiment of the invention, the different use occasions have different requirements on the display screen, the main control CPU processes data, places the data to be displayed in the BUF according to the preset size, sends the data to the display screen CPU through the data line, the display screen receives the BUF and directly displays the data without data processing, and only basic display drive is provided for different display screens without other processing. The application range of the product is improved, and the development workload is reduced.

Compared with the prior art, the invention has the following beneficial effects: in the design of the station terminal, the synchronism of sampling data is improved, the parameter precision of power, power factors and the like is improved, the remote signaling processing speed is improved, the remote signaling resolution and anti-shake are more accurate, the rated current range is flexibly selected, the production error is reduced, and the application range of products is expanded.

Drawings

FIG. 1 is a schematic block diagram of the present invention;

FIG. 2 is a schematic circuit diagram of a sampling control unit (voltage and current sampling) according to the present invention;

FIG. 3 is a schematic diagram of a sampling control unit (remote signaling sampling) circuit of the present invention;

FIG. 4 is a schematic diagram of a sampling control unit (remote sampling) circuit of the present invention;

fig. 5 is a schematic circuit diagram of a permanent magnet mechanism control module of the present invention.

Detailed description of the invention

The following is a more detailed description of the present invention with reference to specific preferred embodiments, and the specific embodiments of the present invention are not limited to these descriptions. For those skilled in the art to which the invention relates, several simple deductions or substitutions may be made without departing from the spirit of the invention, which should be construed as the scope of the invention.

As shown in fig. 1, the present invention provides a design based on an improved Linux system station terminal, and the design mainly relates to optimization of a station terminal implementation process, efficiency improvement and compatibility improvement. The device is composed of the following modules: the system comprises a main processing unit (a core board and a main control board), a sampling control unit (a sampling board and a control output board), a permanent magnet mechanism control unit and a human-computer interaction unit (a display panel), wherein each station terminal comprises the core board, four sampling boards (64 channel telemetering), two control output boards (16-channel remote control) and three control input boards (96 remote signaling). The main control board processes the remote measuring, remote signaling and remote control signals in real time, and achieves the purposes of monitoring, protecting, fault detecting and fault isolating.

As shown in fig. 2, the core board CPU reads data of 4 pieces of AD7616 of the AD chip through an AM335X _ GPMC _ AD 0-AM 335X _ GPMC _ AD15 data bus, samples the data of 4 pieces of AD7616 through the GPMC bus, samples 128 points every period (20 ms), that is, reads the data once every 20ms/128 time interval, directly processes the data, and corrects time errors between different chips through software calibration to achieve data sampling synchronization to the maximum extent.

As shown in fig. 3, the telecommand board signals DZYX 01-DZYX 32 generate parallel-to-serial signals through the isolation circuit and then through 74HC165, sampling through 3 gpio of the core board CPU, while the DZYX 01-DZYX 32 signals generate interrupt signals through 1 gpio of the core board CPU through the gate. If the remote signaling generates displacement, the gate circuit generates a corresponding interrupt signal to inform the CPU to read the remote signaling data.

As shown in fig. 4, the core board CPU generates YCD01 — YCD08 signals through 3 gpio controls 74HC165, and YCD01 — YCD08 signals operate relays on the remote control board through isolation and drive circuits.

As shown in fig. 5, the CPU of the core board sends out remote control signals G1_ N1 and G1_ N2 to control the turn-on of the IGBTs, and the signals G1_ N3 and G1_ N4 are signals obtained by taking a logical not signal for the signals G1_ N1 and G1_ N2. G1_ N1, G1_ N2G 1_ N3 and G1_ N4 realize large instantaneous current and reverse current by turning off 4 IGBTs at high speed, thereby driving the permanent magnet mechanism to operate.

Claims

1. A design based on an improved Linux system station terminal is characterized in that:

(1) a main processing unit: the whole device is processed by adopting a main control CPU, the main control CPU adopts an improved real-time Linux system, the functions of sampling 128 points in each period of 64 sampling channels and sliding window protection judgment once in each 3 sampling points are perfectly realized, the functions of relative real-time protection judgment, fault recording, protocol flexible configuration, software remote updating, fixed value remote downloading and the like are realized, meanwhile, in order to adapt to different display control panels (different occasions require different sizes, types and resolutions of the panels), all display processing is carried out at a CPU end, the display control panel only carries out simple display and does not carry out frame switching processing, namely, the main control CPU sends BUFs which need to be displayed after processing to a display panel through a data line, and the display panel directly puts the BUFs into a display cache; (2) a sampling control unit: the remote control board is composed of a sampling board, a remote control board and a remote communication board, wherein the board cards of the type have no independent CPU and are directly connected with a main processing unit through data lines or signal lines, so that on one hand, the synchronism of sampling can be ensured, and simultaneously, the timeliness of signals such as remote control signals and the like can also be ensured; (3) permanent magnet mechanism control unit: for the mechanism of the permanent magnet mechanism, the control unit is required to be added, the control unit receives a switching-on/off signal sent by a CPU end and controls the energy storage capacitor to realize larger instantaneous current by means of a high-speed switch such as an IGBT (insulated gate bipolar transistor), so that the permanent magnet mechanism is driven to act, and meanwhile, the control unit can monitor the charging and discharging voltage of the energy storage capacitor in real time to determine whether normal switching-on/off operation can be carried out; (4) a human-computer interaction unit: for different application requirements, different human-computer interaction requirements such as size, resolution and background color can be met, and for different requirements, the unit directly places the BUF processed by the main processing unit into a display buffer without performing other processing, so that the increase of development work caused by different display panels is reduced to the maximum extent.

2. The design of the terminal based on the improved Linux system station according to claim 1, wherein the device adopts the improved Linux system, a sampling part adopts 4 pieces of 16-channel AD sampling chips, a CPU reads real-time data from the sampling chips, and then performs certain calibration on the sampled data to achieve efficient synchronization, so as to provide more accurate data for calculation of telemetry values and judgment of protection; in addition, because the rated current of the station terminal is usually 1A or 5A, the device switches the sampling resistor through the analog switch, so that the rated current can be selected through software, and the probability of errors in the production process is reduced.

3. The design of the terminal based on the improved Linux system station is characterized in that the device adopts a protocol highly unified, unified protocols IEC101(IEC104) are adopted for a display panel, maintenance software, an extended remote signaling remote control board and equipment cascading, and a hardware-supported can bus is used for expanding and cascading, so that the expandability and the practicability of the system are enhanced.