Technical Presentations

Lightning Performance Improvement of a 9 MW Photovoltaic Power Plant Connected to a 23 kV Distribution Network892

Abstract
Lightning is one of the main electric hazards a photovoltaic is subjected to. This is due to the large collection area of the plant itself and to the incoming electric lines connected to the plant. Th... see moree main purpose of this paper is to investigate in what cases LV/MV step-up transformers of the PV farm must be protected against overvoltages after a potential lightning strike event. This paper stabilises the lightning assessment simulation process by implementing a computer-based model in EMTP® based on the real engineering design of a 9MW PV plant connected to a 23 kV distribution grid in Chile.

Tag(s): Lightning Photovoltaic, Overvoltage Protection, Step-Up Transformer, Simulation

Experiences in modeling PV plants for grid operators. What is next?865

Abstract
This presentation shows a summary of EMT modelling experiences of PV power plants according to different grid operator requirements. Depending on the study that is demanded, aggregated or disaggregate... see mored representation is needed to characterize the internal network, a simplified method for obtaining an electric equivalent is presented.

Tag(s): PV power plant, average value model, PLL model, power oscillation, voltage oscillation

Optimization of Control Parameters of Grid-Connected PV System in EMTP845

Abstract
It is observed that the controller gain parameters of the PV model have a significant impact on the PV plant’s response during the fault recovery and the PV plant’s interaction with the rest of th... see moree system in general. Manual tuning of the PV park parameter considering multiple fault and contingency scenarios is a time-consuming task and might even be impossible. Optimization techniques such as particle swarm optimization (PSO) can be used to optimize the gain parameters considering fault/ contingency scenarios. The presentation will talk about the implementation of PSO in EMTP using javascript to optimize PV park controller gain parameters.

Tag(s): pv plant, ibr, pso, optimization, scripting, pll, inverter control, inverter based resources, DER

TOV for renewable, evaluating three different grounding technologies783

Abstract
Temporary overvoltages (TOV) are oscillatory overvoltages mainly caused by switching or faults, which are of relatively long duration and undamped or slightly damped. Maximum overvoltages under faulte... see mored conditions can require considerable energy magnitudes absorbed by surge arresters.
These energies may overpass maximum limits and lead to equipment damage.

This project presented a study to identify the maximum TOV at the MV equipment of a PV power plant during fault-clearing events. Two methods of TOV suppression are evaluated, including grounding transformers and fast grounding switches under two different configuraions. An electrical model was elaborated in EMTP to perform the simulation of the transient overvoltage due to the un-balanced fault clearance, considering each inverter of the PV plant. The results show that considering no grounding technologies at the feeders, the energy absorption limit is overpassed in the islanded system.

Therefore, a fast grounding switch or a system with grounding technology at each feeder is needed in order to protect the substation equipment.