Certain events and situations such as lightning strikes, switching operations and fault conditions occurring in day to day operation of a MV or HV power system in a commercial or industrial set-up may give rise to voltage disturbances, more commonly known as Transient Recovery Voltages or Switching Transients. They may not be fatal in their first occurrence but repeated exposure to these transients will reduce the lifespan of power system equipment and may also disturb the stability of the power system putting the entire installation at a risk of shutdown or failure of certain critical equipment.
A Transient Stability Study seeks to improve the reliability of the system under study by minimizing the damaging effects of frequently occurring transients in a power system with the aid of industry standard mitigation methods.
A Transient Stability Study is a two stage process comprising of:
- Identification and Quantization of Transients
The concerned power system under consideration is critically analyzed and modeled using an Electromagnetic Transients Program (EMTP) to discover the root cause of transient disturbance and once identified, a ‘worst case scenario’ is simulated in the program. Key parameters of the transient disturbance such as its magnitude, rate of rise, duration, frequency and energy are extracted from the simulation.
- Designing a Suitable Mitigation Scheme
A suitable mitigation scheme is selected and designed, according to the parameters extracted from the simulation and the characteristic frequency response of the system under consideration, in order to provide the best all round solution for reduction of transients to a safe level.
Some of the mitigation schemes AllumiaX has expertise in, incorporate snubbers and surge arrestors as transient suppressors.
Expected Study Outcomes & Recommendations
The system under consideration is fully evaluated for its ‘worst case’ transient condition and made more robust in response to transients through corrective action recommended by transient stability study. It is therefore expected that:
- System equipment will have a prolonged life and will require less reactive maintenance due to being less prone to damages caused by transients.
- Overall reliability of the system will increase.
A comprehensive set of deliverable reports is provided presenting the findings and recommendations of the transient stability study. The deliverable may be expected to include:
- Detail of the original system under consideration.
- Detail of the simulated system in the Electromagnetic Transient Stability Program.
- Identification of the source of transient disturbance.
- Detail of the worst case transient encountered and its parameters.
- Detail of the simulated system in the Electromagnetic Transient Stability Program after the addition of the mitigation method.
- Design parameters and specifications of the recommended mitigation method.
- Recommended installation practice and location of the mitigation method.
- International standards and code compliance throughout the study process.
All studies conducted by AllumiaX, LLC are in full compliance with the international standards of IEEE, NEC and NFPA.