SAS load shedding

[SESA586716]

Below is the requirement that need to verify from the CPU866e/T500 controller.

We have a requirement of Substation Automation System (SAS) wherein contingency based load shedding is envisaged. There would be approximately 200 IOs. (all digital) and numerical relay communication over IEC 61850. The scheme is to monitor the incomers & load feeders for dynamic load shedding purpose. There will be total 6 different incomers and 50 different feeders for load shedding monitoring.

The incomer / feeder status ( On , Off, Trip) will be a digital input & while commands breaker open & close shall be done using digital Output by means of hardwired control. The dynamic load shedding scheme is based on the runtime MW reading of each incomer & load feeders, the MW data shall be read using IEC 61850 protocol. Based on numerical calculations the actual load shedding shall be initiated as per various contingencies and priority of load shedding.

Now we reach out to you for a solution which will help to meet the timelines for overall load shedding sequence as mentioned below:

The load shedding sequence shall be initiated based on any contingencies by means for any digital input or logical combination. The maximum total time to achieve the load shedding is within 70 ms. The digital output shall drive the interposing relay (response time ~15 ms) which then lead to breaker opening in the field. This entire cycle from sensing of digital input till interposing relay pickup (including interposing relay time) shall be less than 70ms.

We believe with Telvent RTU CPU866e / T500 we can achieve this stringent timeline, help us to provide the confirmation on achieving the timelines.

The Total time 70 ms will be calculated as:

Total Time (70ms) : Input sensed by RTU+ Processing the logics + Processing the output +Interposing relay (~15 ms).

In view of the above scenario can you help us with confirmation that  for above requirement  can we achieve the 75ms timeline with  CPU866e/T500 (Telvent) offer.