Inverter-based resource
An inverter-based resource is a source of electricity that is asynchronously connected to the electrical grid via an electronic power converter ("inverter"). The devices in this category, also known as converter interfaced generation (CIG), include the variable renewable energy generators (wind, solar) and battery storage power stations.[1] These devices lack the intrinsic behaviors (like the inertial response of a synchronous generator) and their features are almost entirely defined by the control algorithms, presenting specific challenges to system stability as their penetration increases,[1] for example, a single software fault can affect all devices of a certain type in a contingency (cf. section on Blue Cut fire below). IBRs are sometimes called non-synchronous generators.[2]
Grid-following vs. grid-forming
A grid-following (GFL) device is synchronized to the local grid voltage and injects an electric current vector aligned with the voltage (in other words, behaves like a current source[3]). The GFL inverters are built into an overwhelming majority of installed IBR devices.[1] Due to their following nature, the GFL device will shutdown if a large voltage/frequency disturbance is observed.[4]
A grid-forming (GFM) device partially mimics the behavior of a synchronous generator: its voltage is controlled by a free-running oscillator that slows down when more energy is withdrawn from the device. Unlike a conventional generator, the GFM device has no overcurrent capacity and thus will react very differently in the short-circuit situation.[1] Adding the GFM capability to a GFL device is not expensive in terms of components, but affects the revenues: in order to support the grid stability by providing extra power when needed, the power semiconductors need to be oversized and energy storage added. Modeling demonstrates, however, that it is possible to run a power system that almost entirely is based on the GFL devices.[5]
Vulnerabilities
One of the most studied major power contingencies that involved IBRs is the Blue Cut Fire of 2016 in Southern California, with a temporary loss of more than a gigawatt of power in a very short time.[6]
Blue Cut fire
The Blue Cut fire in the Cajon Pass on August 16, 2016, has affected multiple high-voltage (500 kV and 287 kV) power transmission lines passing through the canyon, throughout the day, thirteen 500 kV line faults and two 287 kV faults.[7] The faults themselves were transitory (plasma discharge) and self-cleared in a short time, but the unexpected features of the algorithms in the photovoltaics inverter software triggered multiple massive losses of power, with the largest one of almost 1,200 megawatts[8] at 11:45:16 AM.[9]
References
- ^ a b c d Gu & Green 2022, p. 1.
- ^ Khan & Minai 2023, p. 1.
- ^ Khan & Minai 2023, pp. 1–2.
- ^ Khan & Minai 2023, p. 4.
- ^ Gu & Green 2022, p. 2.
- ^ Popiel 2020, p. 5.
- ^ NERC 2017, p. v.
- ^ NERC 2017, p. 2.
- ^ NERC 2017, p. 3.
Sources
- Gu, Yunjie; Green, Timothy C. (2022). "Power System Stability With a High Penetration of Inverter-Based Resources" (PDF). Proceedings of the IEEE: 1–22. doi:10.1109/JPROC.2022.3179826. eISSN 1558-2256. ISSN 0018-9219.
- Nabil Mohammed; Hassan Haes Alhelou; Behrooz Bahrani, eds. (28 February 2023). Grid-Forming Power Inverters: Control and Applications. CRC Press. ISBN 978-1-00-083929-6.
- Khan, Akhlaque Ahmad; Minai, Ahmad Faiz (13 January 2023). "Introduction to Grid-Forming Inverters". Grid-Forming Power Inverters. CRC Press. pp. 1–14. doi:10.1201/9781003302520-1.
- Popiel, Caroline Rose (2020). The Incidence of Inverter Incidents: Understanding and Quantifying Contributions to Risk in Systems with Large Amounts of Inverter-Based Resources (MSc). The University of Vermont.
- NERC (June 2017). 1,200 MW Fault Induced Solar Photovoltaic Resource Interruption Disturbance Report (PDF). North American Electric Reliability Corporation.
 | This electricity-related article is a stub. You can help Wikipedia by expanding it. |