Austrian company OMICRON has rolled out MONCABLO ? a customisable, permanently ?installed system for continuous online monitoring of partial discharge (PD) activity in the electrical insulation of high-voltage (HV) cable systems, including cable terminations and joints
The monitoring system is capable of detecting and locating PD anomalies along the entire length of HV cables. The system is equipped with advanced diagnostic techniques for a reliable evaluation of insulation condition to prevent costly in-service failures at an early stage.
Customisable system design
Thanks to its modular and expandable architecture, MONCABLO can be modified to suit the customer requirements based on the number of cable accessories to be monitored. The system warrants simultaneous PD monitoring of short or long cable links, including buried or tunnel cable systems.
The PD data is synchronously gathered by high-frequency current transformers (HFCTs) installed at the grounding or cross bonding links of each monitored cable accessory, and is transmitted to a data acquisition unit for pre-processing. Multiple data acquisition units are connected to a central computer with fibre optic cable which ensures the galvanic isolation between the high-voltage area and the control room where the central computer is located.
Software with intuitive web interface
The MONCABLO software?s intuitive web interface allows users to remotely configure the monitoring system, to view real-time PD data and historical trends, as well as to analyse the collected raw data. In addition, automated features for PD data evaluation are available via the same web interface. The system can be set up to automatically notify users by email as and when the PD activity exceeds pre-set warning or alarm thresholds. The software also allows the correlation of PD data with the data from third-party sensors (e.g. temperature, oil pressure, etc.) installed on the cable system for complete condition assessment.
IEC 60270 compliant PD measurements
The software permits users to simultaneously view the PD status of all cable accessories in a single overview screen. The PD defects are reliably identified along the entire cable length using a unique patented technology. Such features enable users to make PD measurements for post-installation testing of HV cables.
Advanced technology for convenient PD data evaluation
The high PD measurement sensitivity of the MONCABLO monitoring system is based on advanced OMICRON technology for noise and PD source separation. Multiple PD sources are automatically separated from each other and from external noise through synchronous multi-channel measurements and methods such as the 3-Phase Amplitude Relation Diagram (3PARD) and the 3-Center Frequency Relation Diagram (3CFRD).
Handholding
OMICRON?s dedicated team of service engineers provides users with complete guidance and support during the design, installation, commissioning, set-up and use of the MONCABLO PD monitoring system. OMICRON will also assist with data evaluation and reporting.
Preventing in-service failure of HV cables
HV power cables, terminations and joints are generally factory-tested before installation to ensure quality and reliability. However, mechanical forces during cable laying, hidden imperfections, and flaws caused during the onsite installation of cable accessories can result in partial discharge activity. If undetected, PD will erode the insulation and eventually result in the complete breakdown and in-service failure of the entire cable system. Such failures might lead to unplanned power outages, loss of plant production, adjacent equipment damage, and in some cases, personal injury.
The monitoring of PD activity can aid asset managers in making strategic decisions regarding the repair and replacement of HV cables or accessories and avert untoward incidents. OMICRON has several years of experience in the field of on-line PD monitoring on high-voltage cables with a long list of monitoring projects implemented across the world.
Stand No: H2.D20
