Key Steps and Considerations in Commissioning Substations

Several methods for commissioning substations provide utilities and developers with ways to effectively maintain project schedules. It is widely known in many industries that testing the entire system, as installed, is the best way to ensure performance and system availability.

Here’s an overview of the key steps in commissioning substation protection systems:

  • Test the entire system as installed
  • Provide load to ensure current transformers have enough current to operate
  • Avoid risk by not having to use customer load
  • Test the entire protection system (because when using the grid for load testing, you may have to bypass some protection)
  • Apply a reactive load if the desire is to test distance relays

Changing the tap settings on a transformer is a common way to provide conditions for testing. Considerations when choosing this test method on transformers include:

  • Potential damage to transformers from load imbalance
  • Derived load is highly reactive and will not simulate actual conditions for more complex relays
  • Will not properly test distance, directional overcurrent, power directional or other relays that use current and voltage to operate properly
  • Requires multiple relay settings be manually changed or overridden to “force” the system to test the protection relays
  • Metering may need to be bypassed to perform the test
  • Many protection relay faults are not likely to be discovered

When a new substation is constructed or a substation is upgraded, it must be tested before going live. The commissioning process involves turning on the facility operations, determining what works, identifying any issues and then fixing problems prior to the operation going on-line. Following established standards and proven processes helps ensure a successful utility commissioning.

Download ComRent’s Latest eBook…

For a detailed discussion on utility commissioning, download ComRent’s latest eBook – “Understanding the Commissioning Process for Utility Systems.” This resource discusses the importance of following established standards and proven processes during utility commissioning. It will explain how successful commissioning can lead to greater control, more efficient operations and lower costs.

ComRent’s team of experts is ready to help ensure your system is successfully commissioned. We are offering a complimentary consultation to review your project and propose the right load bank solution for your requirements. Contact us today.

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