IMD (Insulation Monitoring Device) Application Location and Expected Effects in Railway Systems
IMD (Insulation Monitoring Device) measures the insulation resistance between the track and the ground (ground) in real time in the ungrounded (IT) system within the railway system.
It is a monitoring device. When IMD is applied in railway system, the location and effect are as follows.
Applicable location
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Ungrounded (IT) system : All electrical systems that use ungrounded methods, such as railway traction power (DC and AC/DC), vehicle-mounted energy storage systems (ESS), and renewable energy linkage facilities.
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Main control panel and power conversion unit (PCS) side : Sections that require real-time insulation monitoring in the main control panel of the railway system, power conversion unit (PCS) of the vehicle, etc., or require a quick response in the event of an accident.
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Large network sections : Critical distribution sections where maintenance is complex and minimizing downtime is critical.
Applicable Effect
Real-time insulation status monitoring and early warning
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IMD monitors insulation resistance in real time while the line is live, and immediately generates an alarm when insulation degradation or leakage current (ground fault) occurs.
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This can help prevent electrical accidents and greatly improve safety.
Ensuring driving continuity
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Even when the first insulation fault (first ground fault) occurs, the system can continue to operate without stopping. This is the greatest advantage of the ungrounded (IT) system, ensuring the continuity of railway operation.
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Planned maintenance is possible through alerts and fault location tracking rather than immediate shutdown.
Fault location tracking and maintenance efficiency
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IMD provides fault location tracking capabilities to quickly identify the location of an accident and maximize maintenance efficiency.
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Minimize downtime in large rail networks.
Reduce costs and improve system reliability
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Reduce equipment loss, system downtime, and maintenance costs due to electrical accidents.
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It is possible to build a predictive maintenance system through real-time data analysis, which increases reliability and efficiency in the long term.
Compliance with international standards and safety regulations
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By applying IMD that complies with international standards such as IEC 61557-8, global safety standards can be satisfied.
Difference between IMD application and DC leakage current relay (DC relay)
|
division |
IMD(Insulation Monitoring Device) |
DC Leakage Current Relay |
|
Surveillance method |
Real-time monitoring of insulation resistance of non-grounded (IT) systems |
Leakage current detection and immediate shutdown |
|
Driving continuity |
Continue driving on first failure (alarm only) |
Immediately shuts off and stops operation when leakage current is detected |
|
Fault location tracking |
possible |
Impossible |
|
Applicable to |
Ungrounded AC/DC systems (railway, ESS, etc.) |
Mainly for DC circuits and non-critical circuits |
|
Maintenance efficiency |
height |
Low (fault location cannot be tracked) |
IMD is essential for sections where continuous operation is important, such as core power systems of railway systems and vehicle-mounted ESS, while DC Relay can be applied as an auxiliary for non-critical circuits where cost is important.
conclusion
In railway systems, applying IMD (Insulation Monitoring Device) to the main power lines, control panels, and vehicle-mounted ESS of the ungrounded (IT) system can achieve various effects such as real-time insulation monitoring, early warning, fault location tracking, securing operation continuity, improving maintenance efficiency, and reducing costs. This plays a very important role in maximizing the safety, reliability, and operational efficiency of the railway system.