The influence of generator loss of excitation on bulk power system reliability

Loss of excitation of synchronous generator

“…The loss of excitation is a transient phenomenon of medium speed with the time interface of several seconds (3 to 8 seconds according to [6]). The loss of excitation represents a threat mainly from the following reasons [7]: -stator overloading as result of significant supply of reactive power from the grid (0.4 to 1.9 -multiple of S n ), -warming up of rotor winding influenced by induced currents, -extensive swings of active power, which are typical for asynchronous operation.…”

“…Calculations of dynamic stability of grid after loss of excitation of important generators within the grid should also be considered. Since dynamic simulations are time consuming, use of so called screening technique appears to be more suitable [6]. This technique applies classic calculation of power system load flow with the aim to determine critical machines, or nodes in the grid based on so called grid screens where loss of excitation of generator could have adverse effects.…”

Impact of STATCOM and SSSC on synchronous generator LOE protection

“…In this regard, also the reactive power injected by the generator can be measured, which increases the relay performance speed. In [13], it is shown that in a large power system the LOE in the generator is more dangerous for stability of power system. Load flow is utilized for that purpose in this paper.…”

“…Load flow is utilized for that purpose in this paper. In [13], it is shown that LOE is accompanied by generator voltage drop, and using load power flow results, it is shown the LOE in the generator results in voltage collapse in the power system. Investigations in [14] showed LOE protection in isolated systems with an induction motor.…”

The dynamic performance and temperature distribution of turbine generator under loss of excitation by using coupled FE analysis

“…It is a very complicated transient process involving electromagnetic field, temperature field and motion mutual coupled together. The traditional numerical simulation model is Park model [1,2] , it can not fully consider the effect of the changing speed to parameters of the generator. In this paper, FE model is built by considering the following assumptions: 1) Before the fault, the generator is running at rated, connected to an infinite bus.…”