Developing Automatic Meter Reading Systems for Substations in India With NI LabVIEW and CompactRIO
"We developed a flexible substation AMR system with an NI cRIO-9014 embedded real-time controller and a GPRS communication interface to collect data from the remote substation metering device using the NI LabVIEW Real-Time Module."
- Jaswinder Singh, NexGEN Consultancy Pvt. Ltd.
Acquiring accurate and sufficient data to assist in the day-to-day decision-making activities of subtransmission stations and distribution networks for electrical distribution utilities because the electrical network is huge and complex, and it is difficult to improve the situation using the traditional data collection approach.
Developing an advanced automatic meter reading (AMR) system to help utilities access accurate and sufficient data from metering devices and enhance the present electrical distribution network situation in India.
Jaswinder Singh - NexGEN Consultancy Pvt. Ltd.
Ravinder Singh - NexGEN Consultancy Pvt. Ltd.
Abhishek Gaur - NexGEN Consultancy Pvt. Ltd.
Yashwant Shrimali - NexGEN Consultancy Pvt. Ltd.
Deepak Singh - NexGEN Consultancy Pvt. Ltd.
Vaibhav Gupta - NexGEN Consultancy Pvt. Ltd.
We needed an AMR system that could collect data from remote substation metering devices to provide real-time data for long-term data management as well as daily power usage. In addition, the system had to offer automatic reports generation, energy accounting, and graphical representation of the electrical network on a geographic information system (GIS). Also, we needed a system that could help utilities deliver a wide range of services.
Our application addresses the following key challenges with a traditional metering system:
- Dependency on a person for operation
- Large amount of time required for operation
- Human errors
- Limited access to metering device in rural substations
- Collection of data that is inaccurate and cannot be used for reliability analysis
- Inability to perform outage notifications
We developed a flexible substation AMR system with an NI cRIO-9014 embedded real-time controller and a GPRS communication interface to collect data from the remote substation metering device using the NI LabVIEW Real-Time Module. The CompactRIO system provides a good solution for processing data, handling multiple tasks, and communicating with the TCP/IP networking protocol.
The AMR system is used to measure the electrical parameters from feeder metering devices installed at remote substations. We built a GIS-based application to provide a graphical view of the substations at a centralized data center. This software application provides real-time parameters from remote substations that are updated on the GIS.
The software system is divided into five modules:
- Data acquisition from substation metering devices
- Communication between the data center and the CompactRIO controller
- A GIS module
- A substation single-line display/network schematic modeling module
- Reporting and analysis
Figure 1. AMR System Architecture
Data Acquisition From Substation Metering Devices
This module collects data from a network of metering devices installed at incoming and outgoing feeders within the substation. The CompactRIO controller provides a reliable and consistent solution for processing data from the metering devices using Modbus communication protocols. CompactRIO can handle different interfaces including RS232 and analog and digital I/O on a single field-programmable gate array (FPGA), which allows data processing in real time.
The digital I/O module can be used to monitor the status of the circuit breaker and can send a message to the substation in charge via SMS or e-mail if a breaker’s status changes. The module reads the following parameters from the metering device:
- Temper detection
- Maximum demand
- Outage detection
Communication Between the Data Center and CompactRIO
A GPRS module from NI is used as a communication medium that enables communication between the remote station and the data center. The data collected from the AMR interface is transmitted via the GPRS modem using TCP/IP and inserted into a SQL Server database at the data center using the LabVIEW Database Connectivity Toolkit. We built a custom website using the LabVIEW Web publishing tool that provides access to both the real-time and historical data. The system has the capability to log the data to the CompactRIO controller memory in case of a communication failure, and it can retrieve the data when communication is reestablished.
A GIS is used for presenting the location of the power system resources. The idea behind the integration of the GIS and AMRs is to provide the AMR system with a graphical user interface where the electrical network can be visualized, as shown in figures 2 and 3.
The GIS contains special symbols that are dynamically updated with AMR data to continuously represent the current state of the electrical network. The operator has the capability to pan to a desired point on the maps and zoom in or out on that point. The maps automatically change from one level to another at predefined zoom scales to bring up windows containing displays that are familiar to the operator.
Figure 2. The GIS and Substations
Figure 3. The GIS Zoomed In
Substation Single-Line Display
The single-line display (SLD) is used to symbolize substations, the bus configuration of the substations, the transformers, and the breakers. The AMR system updates the metering parameters from the remote substation feeders such as the current in each phase, voltage, power, and energy status of the circuit breakers on the SLD (Figure 4). The detailed parameters can be seen in a separate window (Figure 5). The displayed values are tied to the database and are updated by the AMR system
Figure 4. Substation Single-Line Display
Figure 5. Substation Real-Time Parameters
Network Schematic Modeling
This application has features to draw and document physical electrical network models (substations, HT feeder, transformer, and LT feeder) and can make updates as changes occur (Figure 6). This application is an extension of the AMR system to graphically represent the distribution network and to configure the network elements below the substation level. The data is collected from distribution transformers and pole-mounted metering devices using a handheld device in CSV format. The data collected is then inserted into the database and used for reporting and analysis.
Figure 6. Electrical Network Model
Reports and Analysis
Data collected from the remote metering devices provides the following information and reports:
- Metering devices that were tampered with or are providing readings of zero
- The levels of energy consumed/supplied and energy accounts for a particular duration by a network device (LT feeder, transformer, HT feeder, and substation)
- Maximum demand, voltage levels, current, power consumption/load on each feeder
- Operating condition reports covering peak and base demand, line and transformer/substation loading, power factor, reactive requirements, diversity factor, and voltage conditions
- Reliability reports covering the duration of supply interruptions
- Graphical reports covering load, voltage curves, load duration, and power factor curves
- Maximum demand of LT/HT feeders, transformer, and substations
- Abnormal consumption reports
- Other customized reports such as energy balance, areas of high loss, consumption trends, and load/voltage curve
Figure 7. Graphical Report
Figure 8. Energy Accounting Report
The AMR system we developed using NI hardware and software is a reliable and consistent solution for our power utility. We are able to integrate metering devices, status monitoring, GPRS communication, and software applications such as GIS, data acquisition, SLD, and report generation using a single platform. Because of this, we can avoid the integration issue and reduce development time. The system helps utilities improve electrical network conditions and meets the future challenges of the changing power sector in India.
At the time of this article’s publication, the system had been tested at substations, and we were developing the application to read meters from a number of substations in a distributed network across the geographical region while adding more advanced features to the application.
Explore the NI Developer Community
Discover and collaborate on the latest example code and tutorials with a worldwide community of engineers and scientists.
Who is National Instruments?
National Instruments provides a graphical system design platform for test, control, and embedded design applications that is transforming the way engineers and scientists design, prototype, and deploy systems.