Wind power plant level testing of inertial response with optimised recovery behaviour

Abstract

This study presents and assesses the outcomes of inertial response tests performed on a transmission systemconnected wind power plant in the Canadian province of Quebec. Frequency signals representing a response to a typical loss of generation event were injected into the wind turbines' control systems to artificially trigger an active power increase. The measurement campaign aimed to fulfil two main objectives. First, to validate the performance of a wind turbine control algorithm designed to optimise the active power behaviour after inertial response activation. Second, to study the correlation between individual wind turbine and wind power plant behaviours during, and immediately after, an inertial response event. This publication offers an update on the capabilities and limitations of type 4 wind turbines for providing inertial response functionalities. Furthermore, it underlines the importance of understanding the various parameters that have an impact on the aggregate inertial response of a wind power plant in reality as well as in dynamic simulations. This publication also addresses how simulations can be used to predict the behaviour of inertial response from wind power plants. Final results suggest that current approaches for integrating and evaluating inertial response from wind power plants in system planning studies should be revisited.

Improved Control Strategy of MMC–HVDC to Improve Frequency Support of AC System

“…This method was verified using the hardware-in-loop method. The authors in [4] suggested that the inertial response constant of a single wind turbine was not the inertial response constant of the wind power system; this was verified using field measurements and simulations. In [5], the author explained in detail the calculation method of the inertia constant of the wind turbine with a formula.…”

“…The grid can be operated in a low-inertia state. Therefore, the power system cannot maintain its frequency stability under normal conditions [4,5]. To consider the transmission distance and system stability adjustment of offshore wind power, it is considered that the MMC-HVDC is used to connect the offshore wind power and onshore AC system, and the active power and reactive power control of MMC-HVDC can provide system stability control for AC systems.…”

“…The detailed MMC-HVDC model in [20,21] uses average-value models, which can simplify the calculation. In [4], a high-level capacity of a type-4 wind turbine farm replaces the traditional SG and penetrates the system, resulting in a reduction in the available inertia of the system and oscillation of the system frequency stability.…”

Continuous provision of synthetic inertia with wind turbines: implications for the wind turbine and for the grid

“…There is a variety of publications from different WTG manufacturer describing such a control strategy and the WTG behaviour during frequency response (e.g. [8,9]). Furthermore, a comparison of different WTGs to a real frequency event can be found in a publication by Hydro Québec [6].…”

Continuous grid frequency support with variable synthetic inertia and feedforward pitch angle adjustment

“…In addition, there are various control schemes tailored to the needs of a specific grid operator, e.g. providing a predefined power increase for approximately ten seconds, if a frequency threshold is violated [9]. All have in common that the WT's active power is altered.…”