At a Glance
- Metropolitan Transportation Authority (MTA), New Yort City Transit Authority (NYCT)
- Project Location(s)
- New York City
As New York City Transit (NYCT) placed its latest generation R160 rapid transit cars in service, it experienced “nuisance” substation trips on its busy four-track Queens Boulevard Line (QBL). These trips did not occur due to traction power faults but due to incompatibility between the current draw profile of the new cars and substation protection devices. NYCT needed specialized assistance to understand how to modify substation protection to avoid nuisance trips while maintaining protection from real faults.
LTK used its TrainOps© traction power simulator software to model a mix of R160 and older cars on the QBL. The project area was at the time served by the E, F, R and V trains (V and G now replaced with M) and includes a yard connection to the Jamaica Yard and shops. LTK developed 34 simulation scenarios including normal conditions as well as various degraded power supply scenarios designated by NYCT. TrainOps was used to produce simulated substation and train voltage, current, and power profiles over time. Variance between the power return rail potential and ground potential was also modeled. Transient current characteristics of the R160 cars versus the older DC cars were developed by LTK in order to support NYCT’s selection of feeder breaker transient protection settings.
The TrainOps model’s train performance was calibrated to model real-world train performance. In addition to regular operation, NYCT requested review of substation out of service conditions for each pair of two adjacent substations.