Table of Contents
IEC TR 61850-90-17: Power Quality, PQDIF and WebPQ®
The integration of power quality data into IEC-61850-based station and control system environments is becoming increasingly relevant for utilities, industrial plants and critical infrastructures. The technical report IEC TR 61850-90-17 describes an IEC-61850-based approach for integrating and transmitting power quality measurement data, events and records.
The focus is on communication between power quality instruments, Substation Automation Systems (SAS), SCADA systems and downstream evaluation or import tools. In practice, however, pure control system integration does not cover all requirements of continuous power quality operation.
For live transparency, structured historisation, alarming, device management and IT security, additional platform functions are required. A dedicated power quality platform such as WebPQ® therefore complements standardised integration into IEC-61850 environments with functions for continuous operation.
Key Takeaways
- IEC TR 61850-90-17 provides a technical framework for integrating power quality data, events and records into IEC-61850-based automation environments.
- PQDIF is used as an exchange format for power quality data such as events, characteristic values and records.
- COMTRADE is typically used for fault and transient recordings as well as fault records.
- SCADA systems are suitable for operational management, visualisation and process integration, but they are not specialised for in-depth power quality workflows.
- WebPQ® supports continuous power quality data processing, live visualisation, reporting, alarming, device management and IT security.
Communication of Power Quality Data in Accordance with IEC TR 61850-90-17
IEC TR 61850-90-17 describes how PQ-related data can be transferred between power quality instruments and clients using IEC 61850 concepts. The aim is interoperable communication in utility automation environments.
In general, three central applications are distinguished: live data via MMS, event-oriented messages and records as file transfer via MMS File Services.
Live Data via MMS
Current measured and status values can be provided via MMS using the client/server principle. This includes read and reporting functions for monitoring tasks as well as near-real-time applications, depending on the respective parametrisation.
Events
Power quality events can be reported in an event-oriented manner. Such messages or triggers can be integrated into SCADA workflows, for example as an alarm or as the starting point for an analysis process.
In practical SAS and SCADA environments, this approach is often implemented in such a way that power quality and fault record measurement data are provided in a standardised manner to the control system or to downstream evaluation and import tools.
The focus is not on mapping a complete power quality analysis platform in the control system. Instead, the decisive factor is the standardised integration of PQ information and records into existing IEC 61850 infrastructures.
Data Formats for Power Quality and Fault Records: PQDIF and COMTRADE
Established exchange formats are used for the transmission of power quality and fault data. PQDIF and COMTRADE are particularly relevant. IEC TR 61850-90-17 references these formats in the context of transmitting power quality information and fault records to substation and SCADA systems.
| Format | Application Area | Technical Classification |
|---|---|---|
| PQDIF IEEE 1159.3 | Power quality data, events, characteristic values and records | PQDIF is a standardised exchange format for PQ data and supports cross-manufacturer toolchains. In practice, however, structure and implementation can vary depending on the manufacturer, device, firmware and version. |
| COMTRADE | Fault and transient recordings, fault records and waveforms | COMTRADE is a widely used format for fault analysis and event investigation. It is typically used when high-resolution fault records or waveforms need to be evaluated. |
Why Are Standardised Formats Important?
Standardised formats facilitate the integration of power quality data and fault records into existing system landscapes. They provide a common basis for data exchange, import chains and downstream evaluation processes.
The practical challenge is that the specific implementation can differ depending on the manufacturer and device version. For reliable operation, consistent data structures, monitored import processes and clear interface processes are therefore decisive.
Evaluation of the IEC-61850-Based Approach in SAS and SCADA Environments
The IEC-61850-based approach offers several advantages for integrating power quality data into station and control system environments. At the same time, typical limitations arise when requirements go beyond pure data transfer.
Advantages
- Standardised embedding: Existing engineering and communication structures in IEC 61850 stations can be used.
- System integration: Power quality information and records can be made available in a familiar SAS or SCADA system logic.
- Interoperability goal: The approach is suitable when PQ data is required in the control system context for operational processes, overviews or defined import chains.
Typical Limitations
- File-based mechanisms: PQDIF and COMTRADE are often exported, transferred and imported as files. This can limit timeliness for near-real-time applications.
- SCADA role distribution: SCADA systems are primarily designed for operational management, visualisation and process integration, not for in-depth power quality workflows.
- Operation and security: Device management, update processes, auditability and PQ-specific data quality management typically have to be solved additionally.
What Does This Mean in Practice?
If all application goals have to be achieved, a large number of interfaces often has to be managed. This can result in redundant data transfers and increased complexity in the management of device and interface versions.
PQDIF File Import versus Continuous Data Transfer
PQDIF is an exchange format. Its operational effectiveness depends heavily on the respective integration process. In classic PQDIF import chains, data is exported from the device, transferred and then imported into a tool or SCADA system.
In practice, this often leads to time delay, additional integration and operating effort as well as an increased risk of data gaps. Particularly with many measuring points and large data volumes, batch or file processes can reduce operational efficiency.
These points are particularly relevant if power quality is not only to be documented, but also used continuously for live overview, alerting and rapid incident investigation. Pure file import is often not sufficient for this. Scalable data processing with live transparency, historisation and alarming is required.
| Aspect | Classic File Import | Continuous Data Processing |
|---|---|---|
| Timeliness | Data is packaged and processed downstream. | Measured values and events can be evaluated continuously. |
| Operating effort | Export, transfer, import jobs and monitoring of job chains are required. | Data flows can be operated centrally and continuously. |
| Data quality | Data gaps can occur if process chains are not monitored continuously. | Continuous historisation supports a consistent data basis. |
| Scalability | Many measuring points increase the effort required for file and batch processes. | A central data pipeline supports larger measurement systems more efficiently. |
Requirements for Operation, IT Security and Device Management
Scalable power quality operation typically requires more than the pure transfer of data points or records to the control system. Functions that support the continuous operation of many measuring points are decisive.
These include a scalable data pipeline, live transparency, alarming, reproducible compliance reports and defined processes for operation, IT security and device management. Especially with many permanently installed power quality measurement systems, data flows, device status, user rights and updates must remain centrally controllable.
In the A. Eberle system environment, permanently installed PQSys components such as PQI-LV, PQI-DA smart and PQI-DE form the measurement technology basis for scalable power quality monitoring.
| Requirement | Relevance for PQ Operation |
|---|---|
| Scalable data pipeline | Many measuring points and high data volumes must be processed with a consistent time base and structured historisation. |
| Live transparency and alarming | Current status, trends, limit violations and events must be detected in a timely manner. |
| Reproducible compliance reports | Standardised evaluation and reporting provide a traceable basis for technical measures. |
| IT security in operation | Role and authorisation models, auditability as well as defined update and operating processes support secure operation. |
| Device and fleet management | Central parametrisation, maintenance and controlled rollouts simplify operation throughout the entire life cycle. |
WebPQ® as a Platform for Continuous Power Quality Data Processing
From Pure IEC 61850 Integration to a Dedicated PQ Platform
WebPQ® complements pure SAS and SCADA integration with a dedicated power quality platform that addresses continuous operation. The platform supports live visualisation, structured historisation, reporting, alarming, device management and IT security.
For normal operation, data can be prepared and transmitted in such a way that a reduced continuous data stream is possible. In the event of a fault, high-resolution recordings such as fault recording or DFR can be used specifically. WebPQ® therefore combines efficient data processing with detailed event analysis.
In combination with PQI-DE, PQI-DA smart and PQI-LV, this creates an end-to-end system for power quality measurement, fault record acquisition, analysis, reporting and fleet management.
Continuous Recording and Live Values
Live visualisation and evaluation enable rapid assessment during operation. Structured historisation creates a consistent data basis across many measuring points.
Alarming and Reporting
Notifications, alarms and automated report generation support the transition from measurement data to actionable power quality measures.
Device Management and IT Security
Central administration, parametrisation, user rights management, audit logging and fleet management including firmware updates support secure operation over the life cycle.
User-Friendly Interface
Efficient analysis, report generation and the derivation of measures to stabilise the grid support practice-oriented use.
WebPQ®
Central Platform for Power Quality Data, Reporting and Device Management
WebPQ® supports the continuous processing of power quality data from permanently installed measurement devices and fault recorders. The platform enables live visualisation, structured historisation, reporting, alarming, secure access and central fleet management.
IEC 61850, PQDIF and WebPQ® Working Together
IEC TR 61850-90-17 provides a technical framework for integrating power quality data and records into IEC-61850-based system environments. WebPQ® extends this approach with platform functions that are decisive for the ongoing operation of large measurement systems.
While the IEC-61850-based approach primarily supports structured integration into SAS and SCADA environments, WebPQ® addresses additional requirements from daily power quality operation. These include live transparency, historisation, reporting, alarming, device management and IT security.
| Function | IEC-61850-Based Approach | WebPQ® |
|---|---|---|
| Data transfer | MMS, events and file services | Continuous, bandwidth-optimised direct communication |
| Records | PQDIF and COMTRADE as relevant exchange formats | Use of continuous data streams and high-resolution recordings in the event of a fault |
| Analysis | Integration into the SAS/SCADA context and downstream evaluation chains | Dedicated power quality analysis, trend evaluation, reporting and alarming |
| Operation | Standardised integration into existing IEC 61850 infrastructures | Device management, fleet management, user rights management and audit logging |
Summary and Conclusion
IEC TR 61850-90-17 provides a technical framework for integrating power quality data and records, for example PQDIF and COMTRADE, into IEC-61850-based SAS and SCADA environments. This supports interoperability between measurement devices, substation automation and control systems.
For efficient and scalable power quality operation with high data volumes, however, additional platform functions are decisive. These include continuous data acquisition, live transparency, structured historisation, alarming, reproducible evaluation and secure operating and update processes throughout the device life cycle.
Device and fleet management, patch and device management as well as auditability are essential components of an overall solution against the background of increased cybersecurity requirements. These requirements go beyond pure control system integration and are addressed by a dedicated power quality platform such as WebPQ®.
- Standardised integration: IEC TR 61850-90-17 supports the structured integration of PQ data, events and records into IEC 61850 system landscapes.
- Continuous operation: Additional platform functions are required for live transparency, alarming, historisation and rapid incident investigation.
- Secure scalability: Device management, IT security, audit logging and fleet management support secure operation across many measuring points.
Author
Lukas Rappel
Business Development Manager - PQSys
FAQ - Frequently Asked Questions
What does IEC TR 61850-90-17 describe in relation to power quality?
IEC TR 61850-90-17 describes how power-quality-related data can be transferred between measuring and recording devices and clients using IEC 61850 concepts. The aim is interoperable communication in utility automation environments.
Which applications are distinguished in IEC TR 61850-90-17?
What is PQDIF?
PQDIF is a standardised exchange format for power quality data such as events, characteristic values and records. It supports cross-manufacturer toolchains, but practical implementation can differ depending on the manufacturer, device, firmware and version.
What is COMTRADE?
COMTRADE is a widely used format for fault and transient recordings. It is typically used for fault analysis and event investigation, especially when high-resolution waveforms or fault records need to be evaluated.
Why is pure SCADA integration often not sufficient for power quality?
SCADA systems are primarily designed for operational management, visualisation and process integration. In-depth power quality analyses, consistent PQ reports, trend and event evaluations across many measuring points as well as device management and IT security functions are often implemented in specialised power quality systems.
What advantages does WebPQ® offer for continuous power quality operation?
WebPQ® supports continuous recording, live values, structured historisation, alarming, reporting, device management and IT security. WebPQ® therefore complements pure SAS or SCADA integration with functions that are decisive for operating many measuring points and large data volumes.
When is a dedicated power quality platform useful?
A dedicated power quality platform such as WebPQ® is useful when PQ data is not only to be documented, but also used continuously for live overview, alarming, trend evaluation, compliance reports and rapid incident investigation. This is particularly relevant with many measuring points, high data volumes and increased requirements for IT security and device management.
