Technical Presentations

Reactive Power Energy Management, Analysis of Reactive Power Consumption in Solar Power Plant847

Abstract
For any Power Plant, it is aimed to have maximum Energy Generation and yielding for the Power Output. Solar power plant comprises PV cells, framing array by connecting with each solar panel and then c... see moreonnected with step-up transformer (Inductive element) by cable network (capacitance formed). The energy generated by PV cells are being converted by Solar inverters (Power electronics) and operated at almost Unity Power Factor.
It has been observed that with export of Active energy and increasing output, there is also import of Reactive energy varying with solar generation. The Tariff charges are involved and applicable for Reactive Power Consumption in said solar power plant. Active energy also imported during evening and night hours in absence of solar generation to run critical equipments and trend between active and reactive energy has been observed vice versa.
As per the State Tariff regulations, beneficiary must pay/gets paid for reactive power drawl/supply which is decided and bounded by the system voltage limit (e.g. 97% to 103% of Rated system voltage).

Considering varying MVAR absorption phenomena associated with active power generation and effect of supply voltage, it has been decided to study and model solar generation in EMTP. Different cases have been simulated in EMTP software. Major sources consume Reactive Power identified from modelling and matched observation with actual recorded data. Mitigation technique for reactive power compensation has been studied and modelled. Rating for reactive power compensation source has been validated. Switching phenomena associated with reactive power compensation technique along with voltage profile at different points has also been studied and appropriate rating for switching devices/switchgear has been suggested.
Detail study and simulation results will be shared during presentation.

Tag(s): reactive power, compensation, pv park, inverter

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

Switching overvoltages studies for Live Working791

Abstract
In order to obtain the distances required to perform live working maintenance on the Uruguayan transmission network under secure conditions, electromagnetic transient (EMT) studies are conducted to ob... see moretain the maximum switching overvoltage that can be found in 500-150 kV transmission network. Two different approaches were considered for these studies. On one hand, a simple approach is used, analyzing line switching transients on simplified two line network models. On the other hand, a detailed approach is considered, analyzing line switching overvoltage transients on a complete network model.


This complete model considers 500 kV and 150 kV overhead lines, 500/150 kV transformers, cables, reactive power shunt compensation, hydraulic and thermal generators. Electromagnetic transient studies and the complete network model are performed in EMTP software. Finally, a comparison between the results obtained considering each approach is performed.

STATCOM Integration into a DFIG-based Wind Park and its impact on WP HVRT capability753

Abstract
<p>This presentation presents a research on static synchronous compensator (STATCOM) integration into a doubly-fed induction generator (DFIG) based wind park (WP) in order to fulfill the... see more grid code requirement for power factor control. The STATCOM impact on the WP high voltage ride-through (HVRT) capability is also analysed.</p><p>The WP HVRT capability is assessed by analyzing the responses to a parametric voltage waveform. The external system is represented by a Thevenin equivalent. The pre-described voltage waveforms are applied to the Thevenin source in order to assess the conformity of the HVRT capability to Hydro-Quebec specifications. An actual WP is considered where the simulation model includes all details regarding collector grid and overvoltage protection. The simulations consider various wind turbine (WT) and medium voltage (MV) feeder outage scenarios as well as STATCOM usage for reactive power compensation. A transient function is also proposed for the STATCOM to improve the WP HVRT capability. The simulation results demonstrate that, STATCOM usage provides a noticeable improvement in HVRT capability of the WP, especially with the proposed transient function.</p>