Protective Engineered Safety is developing a world-first technology to tackle a long-standing rail safety challenge: reliable detection of both AC and DC high-voltage lines.
The new AC/DC GoUpSafely system is designed to give operators of rail, tram and light rail networks a tool that until now has not existed – the ability to automatically identify live DC lines during mobile operations.
While alternating current (AC) detection systems are widely used, direct current (DC) has proven far harder to sense. Unlike AC’s dynamic, oscillating fields, DC produces a static electric field that is difficult to measure outdoors where dust, moisture and other electrical “noise” can interfere with readings.
Protective’s Managing Director Karl Rosewarne said the company had been exploring this gap for some time.
“Originally, the DC detection component was included in our 2017 Patent application. We initially concentrated our efforts on the more prevalent A/C detection. However, we were approached by John Holland Group last year to revisit the DC detection. Since then, we have been working diligently to create a bespoke technology that would reliably provide this capability,” he said.
The solution uses sealed static field sensors that can detect the subtle, constant gradient produced by a DC source. Rated to IP68, the units are dust-tight and water-resistant, making them suitable for the harsh rail corridor environment where traditional open-plate field mills can fail.
Machine-mounted protection
The company says the system has the potential to move rail safety beyond reliance on human spotters, who are prone to error and fatigue. By mounting the GoUpSafely sensors directly on maintenance machines or emergency response vehicles, detection can be integrated into the operator’s live controls.
If a hazard is identified, the system could even be linked to motion controls to stop the vehicle automatically.
Testing and refinement
Protective has been validating the GoUpSafely technology through in-house simulations, laboratory trials and field testing. These trials are focused on ensuring the system remains accurate in the electrically “busy” environment of the rail corridor, where stray currents, weather effects and electromagnetic interference from heavy plant equipment can produce false readings.
To counter this, the system incorporates motion-aware filtering, which cross-checks sensor data with the machine’s own movement to avoid nuisance alarms. Karl said testing so far had been encouraging. “So far, the preliminary testing has given us solid positive results. We’re now in the final testing stage, building a full specification scaled-down replica of the DC network that is currently in use within the Australian and European rail networks to conduct our live testing phase. We can then take the solution, once proven, and transform the prototypes into a viable commercial product ready for clients to use,” he said.
The technology is close to full commercial readiness, but is expected to be launched for general use soon. The company is continuing final refinements before a broader rollout.
As rail networks adopt mixed voltages, battery power and renewable integrations, Protective believes the AC/DC GoUpSafely system could set a new global benchmark for high-voltage safety in the sector.