Technical Presentations

Switching of Inductive Currents and Dimensioning of RC-Snubbers with PAMSUITE846

Abstract
In order to control the voltage in distribution and transmission networks shunt reactors can be used for compensation of reactive power. Due to the switching of their inductive currents, unacceptable ... see moreswitching transient voltages might occur which can lead to damage of equipment. Furthermore, the breaker must be able to withstand the transient recovery voltage (TRV), amplitude and rate of rise (RRRV) respectively. One possibility to mitigate these switching transients are so-called RC Snubbers. They have to be dimensioned according to the topology and the values of R and C can be optimized with the PAMSUITE tool. In this presentation the modelling and the results of the TRV due to shunt reactor switching is discussed and the mitigation with RC Snubbers with the help of PAMSUITE is shown.

Tag(s): TRV, PAMSUITE, snubber, switching

Impact of Power Transformer Energization on Relay Protection Operation844

Abstract
One of the main causes of the incorrect operation of transformer relay protection are inrush currents. The transient inrush current occurs when energizing the unloaded transformer, and it is a consequ... see moreence of the transformer core saturation. This paper presents analysis of transients caused by energization of 300 MVA three-phase autotransformer with stabilizing winding and voltage ratios 400/115/10,47 kV.

Using the PAMSUITE Toolbox in EMTP, many simulations were performed to show the impact of model’s parameters on the amplitude and duration of inrush currents as well as the probability of 2nd harmonic differential current amplitude occurrence. Simulation results show that controlled switching reduces inrush currents amplitudes and increases 2nd harmonic content in differential currents. A Protection Toolbox in EMTP was used for modelling CT saturation and operation of transformer’s differential protection relay.

Based on the simulation results the optimal differential protection settings were determined, and the probability of false relay protection operation was calculated.

Tag(s): transformer, energization, inrush, differential, protection, harmonics, bctran, pamsuite

Synchronous condenser transformer energization with PAMSUITE781

Abstract
In engineering studies, getting the necessary input data for performing EMTP simulations may be one of the most challenging tasks.
Indeed, the characteristics of the system under study are usual... see morely badly known for a number of reasons: sometimes they are known with some inaccuracy.
For example when parameters are associated with tolerances; sometimes, the characteristics are completely unknown, for example when the equipment is very old and the datasheets are not available, or when the study is about a future project for which many equipment characteristics are not known yet.

Transformer Energization Study Case with PAMSUITE742

Abstract
<h2 class="title">EMTP Europe User Conference 2019 </h2> <p class="tagline"><b>The EMTP User Conference pres... see moreentations are now available online!</b></p> <p id="text-intro"><b>Transformer Energization Study Case with PAMSUITE</b><br> A number of EMTP studies require parametric simulations. It is namely the case for transformer energization where many uncertain parameters can greatly influence the simulation results. This presentation will show how these kinds of studies can be quickly and easily carry out with PAMSUITE, the EMTP toolbox for parametric studies.