Design and Application of Changshu Changkelong Square Power Management System

An Kerui Cui Tingyu

Jiangsu Ankerui Electric Appliance Manufacturing Co., Ltd.

Abstract : This paper introduces the power management system of Changke Changkelong Plaza and uses smart power meters to collect various electrical parameters and switch signals at the distribution site. The system adopts the on-site local networking method. After networking, it communicates via the field bus and transmits it to the background. The Acrel-3000 energy management system realizes the real-time monitoring of power distribution circuit substations.

Key words: shopping mall; Changshu Changkelong Plaza; floor; smart power meter; Acrel-3000 type; power management system

0 Overview

Chang Ke Long Xing Guang Tian Di is currently the Changzhou region's largest volume and highest level of full-scale leisure and entertainment shopping center. The project has an overall capacity of 80,000 square meters, five floors above ground and two floors underground. It sits in the core area of ​​the new city and is surrounded by high-rise residential buildings. It is the future core commercial entity of the Shimao Commercial Circle; it radiates high-grade property communities, business office areas, and enterprises and institutions, etc. The customer base will fundamentally improve consumers' shopping, leisure and lifestyle, and create more superior and comfortable consumption space for urban residents.

This project is an electric energy management system for Changshu Changkelong Plaza. According to the requirements of power distribution system management, power management needs to be performed separately on the outlets of floor distribution boxes to ensure the safety, reliability, and efficiency of power usage.

Acrel-3000 low-voltage intelligent power distribution system makes full use of the latest developments in modern electronic technology, computer technology, network technology and field bus technology, and performs distributed data collection 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 realizes 0.4kV power distribution system in Changshu Changkelong Plaza for power monitoring and power management. The monitoring range is 590 ARKRAY self-manufactured multi-function power meters for remote real-time monitoring and power management, including 215 PZ80L-E4/C and 375 DTSF1352-C. The system consists of 590 multi-function power meters, divided into 28 buses. All buses are pulled to the serial server through a shielded twisted pair cable and connected to the duty room monitoring host via a TCP/IP network to achieve data connectivity between the meter on the bus and the monitoring host.

The monitoring system adopts a hierarchical distributed structure, ie 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 on-site MODBUS bus network communication, data acquisition on the spot.

The network communication layer is mainly: serial port server, its main function is to convert RS485 signal into RS232 signal, 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 to connect the wires. 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 main functions of the power management system

2.1 Data Acquisition and Processing

Data acquisition is the basis of power distribution monitoring. Data collection is mainly accomplished by the underlying multi-function network instrumentation, realizing 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.

The data processing mainly displays 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, and store the collected data 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 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 the 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 user modification of accounts and permissions.

2.6 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 Studies

The Changshu Changkelong Plaza power management system monitoring area is a floor distribution box. This project is to implement power monitoring and power management for the floor distribution system.

All circuits in the site adopt PZ80L-E4/KC and DTSF1352-C multi-function meters. It is a network power meter designed for the power management 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, reactive power and other electrical parameters. In addition, this instrument has 2 optically isolated digital input contacts. These contacts can be used with intelligent circuit breakers to achieve remote signaling operation of the circuit breaker. The series of network power meters are mainly used in substation automation, distribution network automation, residential energy management, industrial automation, energy management systems and intelligent buildings and other fields.

The secondary diagram of low-voltage power distribution is shown in figure (2). The main function of the power telemetry is to monitor the electrical parameters of the operating equipment, including: three-phase voltage, current, power, power factor, electrical energy, frequency and other electrical parameters and distribution loops. Three-phase current; remote signal function to display the operating status of field devices, mainly including: switching of the switch, closing operation status and communication failure alarm; when the circuit breaker is dislocated, it will send an alarm signal to remind the user to deal with 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 interface to remind the on-duty personnel to deal with it in time. The load limit can be set freely under the corresponding authority. With history query function. See Figure (3).

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

The parameter reading function mainly inquires into the electrical parameters of the low-voltage outlet circuit. Supports electrical parameter query at any time, with functions such as data export and report printing. The report queries the electrical parameters of each low-voltage circuit on the floor, including: three-phase current, active power and active power, and transformer temperature. 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 names of the loops in this report are associated with the database to facilitate the user to modify the loop name. 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).

Figure (5) 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 communication failure, green indicates normal communication. See Figure (6).

Figure (6) System Communication Structure

4 Conclusion

With the development of society and the wide application of electricity, the power management system has become an inevitable choice for large-scale multi-substation users, such as key projects, landmark buildings, and large-scale public facilities throughout the country. The Acrel-3000 energy management system introduced in this paper is introduced. The application in Changshu Changkelong Plaza can realize the real-time monitoring and power management of the power distribution circuit on the floor. It can not only show the power status of the circuit, but also has the function of network communication. It can be composed of serial server, computer and other power management systems. Convenient remote management of on-duty personnel will help save energy meter reading time and bring information into distribution monitoring. The system analyzes and processes the collected data, displays the running 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 users of substations to solve electricity problems and has achieved good social benefits. [2]

references:

[1]. Ren Cheng, Zhou Zhongzhong. Principles and Application Guide for Digital Meters for Electric Power Measurement [M]. Beijing. China Electric Power Press, 2007. 4

[2]. Zhou Zhongzhong. The product selection and solution of smart grid user end power management and power management system [M]. Beijing. Machinery Industry Press. 2011.10

About the author: Cui Tingyu, male, undergraduate, Jiangsu Ankerui Electric Manufacturing Co., Ltd., the main research direction for intelligent building power supply and distribution monitoring system. Email:el.cn QQ Mobile Phone Fax Website: http://