Power Management System Transformation Program Introduction
Xiaoqin Yang (East China Architecture Design and Research Institute Co., Ltd., Shanghai 200002, China)
Li Hua (Harbin Urban and Rural Planning and Design Institute, Harbin 150010, China)
Cao Xuehua (Shanghai Ankerui Electric Co., Ltd., Shanghai 201801)
Introduction of Electric Management System
Yang Xiaoqin (East China Architectural Design & Research Institute Co., Ltd., Shanghai 200002, China)
Li Hua(Harbin Urban Planning and Desige Research Institute, Harbin 150010, China)
Cao Xuehua (Shanghai Acrel Ltd., Shanghai 201801, China)
Abstract Acrel-3000 electric energy managent system for a factory distribution system has been Reconstructed to achieve various power distribution circuits for remote monitoring and centralized management, it can automatically calculate the energy consumption per unit output in order to provide a scientific basis for energy-saving The management.The structure,functions and sofeware implementation of the electric energy management system are introducted.The characteristics and communication cable wiring of the ADL rail-installation election energy meter are especially introducted.
Key words Electric energy management system Electric energy meter Rail-installation RS485 communication
Abstract Using the Acrel-3000 power management system, the power distribution system of a certain factory was reconstructed, and the remote monitoring and centralized management of each distribution circuit was realized. The energy consumption per unit of output can be calculated automatically, providing a basis for scientific energy management. . Introduce the structure, function and software implementation of the power management system. In particular, the characteristics of the ADL rail mounted energy meter and the wiring of the communication cable were introduced.
Keywords power management system, energy meter, rail mounting, RS485 communication
1 Introduction
In response to a series of policies and measures formulated by the State Council to promote energy conservation and emission reduction, all walks of life in the country have actively taken measures to save energy and conserve electricity, and have made positive progress. However, whether the implementation of energy-saving schemes for electricity and the widespread adoption of energy-saving equipment for energy use have really played a role in energy saving, scientific assessment must be conducted with a reasonable assessment and management mechanism.
A company's plant has a phase 1 power distribution room and 2 power distribution rooms, providing production, lighting, air-conditioning and other electricity. The original power distribution system is only equipped with the power meter of the power department on the total line of the whole plant. The manager can only know the total amount of electricity provided by the power department in each month. Wherever there is, whether there is wasted energy and whether the energy-saving measures have received the desired results, business managers are not very clear. Urgently a reasonable energy assessment mechanism to achieve the scientific management of electrical energy.
In response to the above problems, and according to customer requirements, the original distribution system was reconstructed. The transformed Acrel-3000 energy management system not only enables remote monitoring and centralized management of each distribution circuit, but also realizes The monitoring equipment carries out classification of energy statistics, multi-rate energy statistics, eight-hour group energy consumption statistics, daily energy consumption statistics, and monthly energy consumption statistics, and automatically calculates energy consumption per unit of energy consumption, which provides scientific basis for energy conservation management.
2 Project Analysis
The power management system is to add a power meter with a communication interface on the basis of the original transmission and distribution cabinet, and remotely transmit the power parameters to the monitoring center, thereby realizing a centralized, remote monitoring and management of a low-voltage power distribution transformation project.
To realize the statistics of the power consumption of each machine, and to collect the energy data of each outlet circuit, one energy meter must be installed in each outlet circuit. However, the traditional metering table on the market generally adopts the traditional wall-mounting method. The installation method is bulky and inconvenient to install. The distribution cabinets of the original distribution system of the company are all drawer cabinets. Current meters and signal indicators have been installed on the panel of the original drawer cabinet. The installation space is very small and it is not possible to add any traditional energy meter to the drawer panel. The components installed inside the drawer are already very tight, and it is impossible to install a traditional energy meter or a digital power network instrument.
If measuring lines are taken from each circuit transformer, a new meter box is re-placed next to the power distribution cabinet, and the meter is centrally installed in the meter box. This method will make the cable from the meter box to the power distribution cabinet particularly large. In view of the large number of power distribution circuits in the company's power plant, the installation wiring is more troublesome, and the maintenance and repairs will be more difficult later, adding so many cables and cables. The new meter box will also increase the user's economic costs, so this method is not desirable.
Taking into account various factors such as instrument installation, commissioning and post-maintenance, the ADL series rail-mounted energy meter was eventually selected. The series of meters can be easily installed on the guide rails on the rear of the power distribution cabinet. It is not necessary to re-open the holes in the power distribution cabinet, and it is not necessary to lead a large number of cables to the new meter box. The installation is convenient and saves a large number of cables and meters. The cost of the box, and this kind of one-on-one measurement, is also very clear and convenient for the future maintenance of the system.
ADL series rail energy meters all have a standard RS485 communication interface, adopt Modbus RTU international standard communication protocol, and connect the instrument network through the instrument's communication interface, and finally achieve centralized monitoring and management in the monitoring center.
3 ADL Rail Mount Energy Meter
ADL series rail-mounted energy meter includes single-phase multi-rate meter and three-phase multi-rate meter. This series of energy meter is small in size, beautiful in appearance, modular in structure, and can be mounted on 35mm standard rails. Figure 1 shows the appearance and installation of ADL series instruments.
ADL series rail-mounted energy meter supports two connection modes of one-time access and two-time access. It can be used not only in low-voltage power distribution cabinets, but also in terminal distribution boxes. The maximum size of ammeter is 20(80)A.
ADL series rail-mounted energy meter not only has flexible and convenient features in appearance and wiring, but also has the following advantages in function and performance:
a. Measure positive and negative active power, automatic power flow direction identification and indication, with 4 rates and total energy metering function.
b. Time-division and multi-rate function, 4 hours rate and 8 hours can be set during the day period, and the minimum time unit within the period is 1 minute.
c. The monthly rollover function can be used to count the total power consumption and time-sharing power of the previous month, the previous month and the current month, and be used for the settlement of monthly electricity charges and the monitoring of electricity usage.
d. Real-time monitoring function, measuring display voltage, current, frequency, power, power factor.
e. Output interface. With photoelectric isolation of the power pulse data output interface, can be used for calibration and implementation of DCS (Distribution Control System) remote transmission, RS485 communication interface can achieve remote meter reading and load monitoring.
4 System Components The power management retrofit system employs a hierarchical distributed computer network architecture, namely, a bay layer, a communications layer, and a station control layer, as shown in FIG.
Shielded twisted-pair wires are used for bus-type connection between the meters, and they enter the monitoring host through the communication expansion card. Figure 3 shows the ADL meter communication cable wiring diagram. Through the networking of the secondary equipment of the distribution system, the monitoring host is reached via the communication network, and the field devices of the decentralized distribution center are connected as a whole.
The monitoring center is configured to monitor computers, printers, UPS power supplies and necessary auxiliary equipment. The Acrel-3000 energy management software completes the remote acquisition and data processing of each power meter.
5 Software Implementation and System Functions
5. 1 software implementation
The upper computer software uses Acrel-3000 configuration software, through the software for device configuration, database variable configuration, interface design, etc., to complete the software on the host computer software monitoring and power management.
5. 2 System Functions
The entire system realizes the collection and statistics of all loop energy of the first-phase power distribution room and the second-phase power distribution room, remote automatic meter reading, energy statistics and other functions, including:
a. Remote power parameter measurement, including real-time power, spread power, total power, and statistics by each monitoring device.
b. Operation status monitoring, communication error alarm.
c. User management, different user rights have different operation functions, each level of authority has password modification operation function and permission error prevention function.
d. The energy report enables time-based query of all energy reports and is divided into five types: minutes, hours, team, day, and month, including total, sharp, peak, flat, and grain rate power and electricity consumption.
e. Electrical energy bar graph, real-time energy column graph display of any circuit energy, including total, sharp, peak, level and valley energy.
f. Summary table, all monitoring equipment energy summary, according to the time period query, automatic calculation of electricity consumption for any period of time.
g. Unit energy consumption, automatic calculation of unit output energy consumption, and printing and exporting. The unit output energy consumption calculation interface is shown in Figure 4.
h. Print and export, all reports and interfaces can be printed, or exported in EXCEL, WORD format.
6 Conclusion
The system has been debugged and accepted. At present, it has been successfully put into operation. The refresh time of the system software screen is less than 1s, and the remote signal processing accuracy is greater than 99.9%. The entire system runs safely and stably, which greatly facilitates the use of the user.
The application of ADL rail-type energy meter has practical significance for accurately measuring electric energy, saving installation space and saving engineering cost. Compared with traditional wall-mounted electric meter, the ADL rail-type electric energy meter has compact size, simple shape, flexible wiring, and convenient installation. The simplification and centralization of the management system provide convenience.
The system completely calculated each monitoring equipment according to the customer's requirements, calculated the number of energy sharing of the common equipment and the energy consumption per unit of production, and made four types of reports: minute, hour, day, and month. The convenient electrical energy database report has greatly reduced the user's investment in the power meter reading labor, provided an intuitive basis for the managers to perform internal measurement assessment, and laid the foundation for further energy conservation management and implementation of energy-saving measures.
references
1 Ren Chengcheng, Zhou Zhong. Principles and Application Guide for Digital Power Meters. Beijing. China Electric Power Press, 2007:
