The PDMonitor, which utilizes Ultra High Frequency (UHF), Acoustic Emission (AE) and High Frequency Current Transformer (HFCT) sensors and is designed to conduct real time online monitoring to detect and analyze potential Partial Discharge (PD) signals and insulation faults before they lead to breakdown or catastrophic failure in power assets. The system provides the developing trend of the PD, when occurring, as alarms in real time, thus helping to predict the insulation degradation status of the asset, prevent sudden accidents, and provide an effective database for Condition-Based Maintenance (CBM) of power assets.
The Main Unit connects with sensors by coaxial cables and has built-in memory for storing the data collected. It collects data continuously from the sensors, processes the data and uploads the data to the DSU by optical fibers.
The Diagnostic Server Unit (DSU)
The Diagnostic Server Unit (DSU) receives data from all Main Units through optical fibers and displays the system configuration, monitoring data, diagnostic results, and alarms in real time. It consists of a server, a monitor, a keyboard, switches, etc., which are installed in a standard cabinet. It is usually placed in the monitoring room in a substation/power plant and used by the station operators and/or management personnel.
The system consists of Sensors, Main Units, a Diagnostic Server Unit (DSU), PDMonitor Software, and Coaxial Cables. Signals are collected through the Main Units and then analyzed by the PDMonitor Software. If detected, the PD type and approximate location are identified and maintenance suggestions are provided. The system can support more than 250 Main Units and each Main Unit supports up to 8 channels, totaling 2000 sensors.
Advanced PD Monitoring and Diagnostic Software.
The PDMonitor software is used to control all of the Main Units to collect data, transmit, process, and save the data into the database, as well as analyze the data and provide diagnostic results. It has the following features:
• Displays PRPD, PRPS, φ-q, φ-n, q-n, q-t, and n-t data spectrums with diagnostic results for each channel in real time.
• Identifies the possible PD type according to- the signal characteristics through PMDT’s intelligent diagnostic algorithm.
• Through the statistics and analysis of the historic data, the system displays the developing trend of the PD signals that have been collected. Historical PD data trend statistics can be reviewed over a period of time.
• The database system records and displays all monitoring data as well as spectrums. Data can be viewed using filtering choices such as sensor/sampling time/PD data.
• Built-in Fingerprint Library with PRPD and PRPS characteristics spectrums database of typical PD and noise/disturbance signals.
• Alarms are sent automatically by emails or mobile SMS when the monitored signals reach the pre-set alarm parameters. Alarms are also recorded and can be viewed at any time.
• Supports remote access and database export/import.
Real Time Data Display
Historical Data Analysis