Design and Application of Nexteer Automotive Systems (Suzhou) Co., Ltd. Power Monitoring System

Qi Xiaoqing

Jiangsu Ankerui Electric Appliance Manufacturing Co., Ltd.

Abstract: The power monitoring system of Nexteer Automotive Systems (Suzhou) Co., Ltd. is introduced. Intelligent power meters are used to collect various electrical parameters and switching signals at the distribution site. The system adopts a combination of fiber networking and local networking. After the network is transmitted to the back-end through the fiber network, the Acrel-2000 power monitoring system is used to realize real-time monitoring of power distribution circuit substations.

Keywords: Large manufacturing company; Nexteer Automotive Systems (Suzhou) Co., Ltd.; 0.4KV Substation; Intelligent Power Meter; Acrel-2000; Power Monitoring System

0. Overview

Nexteer Automotive Systems (Suzhou) Co., Ltd. is located in the east of South Zhongxin Road, Fengli Street, Xietang Town, Suzhou City. The factory covers an area of ​​approximately 4.6 hectares and a total investment of 45 million US dollars.

This project is the power monitoring system of the distribution center set up by Nexteer Automotive for the North-South substation. According to the requirements of power distribution system management, it is necessary to perform power monitoring on the low-voltage distribution outlets in the two substations of the two factories of the Nexteer North and South, and also to access the power distribution of the five large air compressors in the workshop. Circuits to ensure the safety, reliability and efficiency of electricity use.

Acrel-2000 low-voltage intelligent power distribution system takes full advantage of the latest developments in modern electronic technology, computer technology, network technology and fieldbus technology, and conducts distributed data acquisition and centralized monitoring and management of the power distribution system. The secondary equipment of the distribution system is networked. Through the computer and the communication network, the field devices of the decentralized power distribution station are connected into an organic whole, and the remote monitoring and centralized management of the power grid operation is realized.

1. System Structure Description

The monitoring system mainly implements the 0.4kV distribution system of Nexteer Automotive 2 substations for power monitoring and power management. The monitoring range is for two 0.4KV transformer substations, low-voltage line cabinets, connection cabinets and feeder cabinets. 105 Ankerui own DINSF1352-CF rail-mounted energy meters and five air compressor distribution circuits in the workshop. Kerui's self-steering rail-type energy meter with model number DTSF1352-CF can realize remote real-time monitoring and power management in the background through the monitoring of the above-mentioned monitoring range. The system has 73 multifunction power meters in the Southern District Substation and 3 multifunction power meters in the South Air Compressor circuit. The bus is connected to the South District Central Acquisition Unit in 5 buses, and 31 multifunction instruments in the North Substation. And North District air compressor 2 multi-function instrument, divided into 4 buses to access the North Branch Center acquisition device, and then pull the fiber optic network to the main engine room monitoring host, to achieve the bus on the meter and monitoring host data connectivity.

The monitoring system adopts a hierarchical distributed structure, namely station control layer, communication layer and bay layer; as shown in Figure (1):

Figure (1) Low-voltage network topology

The main equipment for the bay is: Ankerui multi-function network power meter, switch, analog acquisition module and intelligent circuit breaker. These devices are corresponding to the corresponding primary equipment installed in the electrical cabinet, these devices are used RS485 communication interface, through the scene MODBUS bus and fiber network network communication, data acquisition on the spot.

The main network communication layer is: serial port server and network switch. Its main function is to convert RS485 signal into TCP/IP signal and complete the data exchange between the field layer and station control layer.

Station control management: equipped with high-performance industrial computers, monitors, UPS power supplies, printers and other equipment. The monitoring system is installed on the computer to collect and display the operating status of the field equipment and display it to the user in the form of human-computer interaction.

The above network instruments all adopt RS485 interface and MODBUS-RTU communication protocol. RS485 adopts shielded wire transmission. Generally, two wires are used for connection. The connection is simple and convenient. The communication interface is half-duplex communication, that is, both parties can receive and send data. Only data can be sent or received at the same time. The maximum data transmission rate is 10Mbps.

The RS485 interface is a combination of balanced drivers and differential receivers. It has enhanced noise immunity and allows up to 32 devices to be connected on the bus. The maximum transmission distance is 1.2 km.

2. The main functions of the power monitoring system

2.1 Data Acquisition and Processing

Data acquisition is the basis of power distribution monitoring. Data collection is mainly completed by the underlying multi-function network instrument to achieve local real-time display of remote data. The signals that need to be collected include: three-phase voltage U, three-phase current I, frequency Hz, power P, power factor COSφ, power Epi, and remote device operating status.

Data processing is mainly to display the electrical parameters collected according to requirements in real time and accurately to the user, so as to meet the requirements of automation and intelligence of the power distribution monitoring. At the same time, the collected data is stored in the database for user query.

2.2 Human-computer interaction

The system provides simple, easy to use, and good user interface. Using the Chinese interface, the CAD graphic shows the electrical main wiring diagram of the low voltage distribution system, shows the status of the distribution system equipment and the corresponding real-time operating parameters, the screen timing switching tour; dynamic refresh of the screen in real time; analog display; switch display; continuous Record display and so on.

2.3 Historical events

The historical event viewing interface provides convenient and friendly human-computer interaction for the user to view fault records, signal records, operation records, and over-limit records that have occurred. You can view the platform through historical events. You can easily locate your own according to your requirements and query conditions. The historical events that you want to view provide you with good software support for the overall system operation.

2.4 Database Establishment and Query

It mainly completes remote measurement and remote signal acquisition, and establishes a database to generate reports regularly for users to query and print.

2.5 User Rights Management

For different levels of users, different permission groups are set to prevent the losses caused by human misoperation to production and life, and to realize the safe and reliable operation of the distribution system. You can use user management to perform user login, user logout, password change, and add/delete operations to facilitate the user's modification of accounts and permissions.

2.6 Running load curve

The load trend curve function is mainly responsible for regularly collecting incoming lines and important loop current and power load parameters, and automatically generating running load trend curves to facilitate users to know the operating load status of the equipment in a timely manner. Click the corresponding button or menu item of the screen to complete the switching of the corresponding function; you can view the real-time trend curve or historical trend line; the selected curve can be translated, zoomed, range conversion and other operations to help the user to enter the line trend analysis and fault recall. Analyzing the entire system's operating status provides intuitive and convenient software support.

2.7 Remote Report Query

The main function of the report management program is to design the report style according to the needs of the user, and the data processed in the system is filtered, combined and statistically generated to generate the report data required by the user. This program can also be based on the needs of users of the report file to save, print or summon save, print mode. At the same time, this program also provides users with management functions for generated report files. The report has the functions of freely setting the query time to realize daily, monthly, and annual energy statistics, data export, and report printing.

3. Case study

The monitoring area of ​​Nexteer Automotive Systems (Suzhou) Co., Ltd. power monitoring system is 2 substations and large workshop air compressors. The monitoring scope of this project is the low-voltage incoming line cabinet and the contact cabinet of the 0.4KV low-voltage circuit in the power distribution center. The distribution circuit of feeder cabinets and air compressors provides remote real-time monitoring and power management through distributed networking.

The DTSF1352-CF DIN rail multi-function meter is used for the in-out line circuit. It is a network power meter designed for the power monitoring needs of power systems, industrial and mining enterprises, public facilities, and intelligent buildings. It can measure all conventional power parameters such as: Three-phase voltage, current, active power, reactive power, power factor, frequency, active power, and reactive power, and the meter is equipped with one optically isolated switch input contact. The series of network power meters are mainly used in substation automation, distribution network automation, residential power monitoring, industrial automation, energy management systems and intelligent buildings.

The secondary diagram of low-voltage power distribution is shown in figure (2). The function has the power of telemetry to mainly monitor the electrical parameters of the operating equipment, including: three-phase voltage, current, power, power factor, electrical energy, frequency and other electrical parameters and three out of the loop Phase current; Remote signal function Realize the running status of the display field equipment, mainly including: switch's dividing, closing running status and communication failure alarm; When the circuit breaker is dislocated, it will send an alarm signal to remind the user to handle the fault in time.

Figure (2) Secondary diagram of low voltage distribution

The remote signaling and telemetry alarm functions mainly complete the monitoring of the switching operation status and load incoming line of the low-voltage outlet loops, and indicate the specific alarm position and audible alarm to the switch displacement and load over-limit pop-up alarm interfaces, prompting the on-duty personnel to deal with them in time. With history query function. See Figure (3).

Figure (3) Real-time remote alarm information map and historical telemetry alarm information query

Parameter reading function, mainly for the low-voltage outlet circuit of the electrical parameters into the line query, with data export and report printing functions. The report queries the electrical parameters of the low-voltage loops on the incoming and outgoing lines, which mainly include: three-phase current, active power, and active power. The names of the loops in this report are associated with the database to facilitate the user to modify the loop name. See Figure (4).

Figure (4) Parameter reading

The electricity consumption report function can select the time period to inquire, supports the accumulated electricity inquiry at any time, and has the functions of data export and report printing. Provide accurate and reliable power report for duty personnel. The name of each loop of this report is associated with the database, which is convenient for the user to modify the loop name. In addition, a multi-rate meter reading meter is also set. As shown in the figure below, the precise power consumption of each distribution circuit in a certain period of time, the user can directly print the report, and can be saved to other locations in EXCEL format. See Figure (5) and Figure (6).

Figure (5) Energy Report

Figure (6) Multi-rate Energy Report

The schematic diagram of the system communication structure mainly shows the networking structure of the system. The system adopts a hierarchical distributed structure and simultaneously monitors the communication status of the equipment at the bay level. Red indicates normal communication and green indicates communication failure. See Figure (7).

Figure (7) System Communication Structure

The load trend curve interface allows you to visually check the load operation of the loop. View real-time and historical trend curves, click the corresponding button or menu item to complete the switching of corresponding functions; help the user to enter the trend analysis and fault recall, with curve printing function. Provides intuitive and convenient software support for analyzing the health of the entire system. See Figure (8).

Graph (8) Trend Graph

Air compressor curve interface can be intuitively viewed five air compressor circuit load curve, and five air compressor curve comparison, with curve print function. It provides intuitive and convenient software support for analyzing the operating status of air compressor power consumption. See figure (9).

Figure (9) Air compressor curve

In the limit setting interface, the upper and lower limits of the alarm can be customized according to the on-site requirements. The quantities covered include: current, voltage, power, and power factor. This setting is updated in real time and does not require restarting the software. It is convenient, flexible, and flexible. It provides intuitive and convenient software support for follow-up users to facilitate the management of power supply and distribution. See figure (10).

Figure (10) limit setting diagram

4 Conclusion

With the development of society and the wide application of electricity, the power monitoring system has become an inevitable choice for large-scale multi-substation users, such as key construction projects, landmark buildings, and large-scale public facilities throughout the country. The Acrel-2000 power monitoring system introduced in this paper is introduced. In the application of Nexteer Automotive Systems (Suzhou) Co., Ltd., real-time monitoring and power management of power substation low-voltage distribution circuits can be realized. It can not only show the power status of the circuit, but also has the function of network communication, and can be used in industrial The network switch, serial port server, computer and other components constitute the power monitoring system, which facilitates the remote management of the on-duty personnel of the substation, which helps to save the time of energy meter reading and brings informatization into the power distribution monitoring. The system analyzes and processes the collected data, displays the operating status of each distribution circuit in the substation in real time, has a pop-up alarm dialog box and voice prompts for the closing and closing of the load, and generates various energy reports and analysis curves. Graphics, etc., to facilitate remote meter reading and analysis, research. The system is safe, reliable, and stable. It provides real and reliable basis for substation users to solve power problems, and has achieved good social benefits. [2]

references:

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[2].Zhou Zhouzhong, et al. Product Selection and Solution for Smart Grid User-end Power Monitoring and Power Management System[M]. Beijing. Machinery Industry Press. 2011.10