Industries need continuous power to keep their processes running. Utilities strive to ensure the highest possible supply availability for customers. During power distribution, network operators need to comply with regulations to ensure a stable and available power supply. In all cases, manual control of redundant systems is complex and thus prone to human error and time-consuming.
To better manage the increasingly complex demands these industries face, technologies focused on automation and communications are key to creating a self-healing grid that will protect asset-intensive industries from outages, ensure customer satisfaction, and support the Renewable energy is incorporated into the grid in a stable and safe manner.
This is especially important as increased demand on the grid will force power operators to provide a reliable, uninterrupted supply of electricity. Going forward, it is clear that the power systems industry needs to embed two key assets into the future development of the grid: flexibility and resiliency.
Flexibility and resilience
In 2018, the number of power outages in the United States peaked at 5.8 hours per customer. As 2021 rolls around, flexibility will mean quicker responses to unforeseen circumstances such as weather disruptions and supply changes. Therefore, while some basic measures to support the grid require manual operation, the use of technologies such as automatic transmission systems (ATS) and remote terminal units (RTUs) can help support automated decision-making.
Take, for example, a leading power company in northern Hungary. By monitoring and controlling the automated distribution network of pole-top overhead line switches and secondary substations, they are able to uncover fault detection and directional information, and speed up response time in the event of an outage.
The need for our second asset, resilience, best stems from the fragility of global supply chains observed during the Covid-19 crisis. Of course, the energy system is also based on global supply chains, but unlike other industries, national policies are used to mitigate the risk of supply disruptions from local reserves. Countries store natural gas, oil or coal for weeks or even months, and converting these energy carriers into electricity used to be local. But that concept is changing with increasing reliance on geographically concentrated renewable energy sources. The power systems of the future will be more interconnected, and they will operate closer to their limits—and therefore more vulnerable. Since large amounts of wind energy, solar radiation or electricity cannot be stored, new concepts are needed.
So resilience, the ability to survive critical situations rather than focus on avoiding them, will become even more important. This is especially true where systems become more complex and potentially vulnerable with more interconnections. As a result, digital systems will rely more on communication infrastructure. Resilience in this context means that they can still provide essential functionality in case those infrastructures become unavailable.
So how is all this possible?
The first step in a self-healing grid is an RTU-based Automatic Transmission System (ATS), which is especially suitable for avoiding long interruptions in low- and medium-voltage power supplies and is used in small industries, utilities, data centers, transportation in commercial and public buildings middle.
Specifically, the RTU hardware-based ATS function is designed for emergency lights, hazard ventilation, cooling systems, communication systems and delayed transmission in alarm processing and monitoring to ensure continuous power supply in combination with battery systems or generators.
One of Switzerland's largest airports has experienced the system firsthand. The airport has multiple emergency power supply groups. The 16kV medium voltage (MV) network is divided into autonomous sectors. Each sector has a medium-voltage substation (so-called terminal station) as well as several substations. The substation includes the main connection to the terminal station of the ring connection option between the substations. This concept improves the power supply reliability of the building. Use RTUs to autonomously control and monitor all parts of an airport's medium-voltage power supply, ensuring that the millions of passengers, cargo and flights the airport supports are always up and running.
The following is an example of Fault Detection Isolation and Recovery (FDIR) for an open loop configuration:
Grids are making a smart transition to geographic distribution. Maintaining so many devices with limited human resources is a huge challenge for network operators. RTU provides a secure interface for network operators to stay up-to-date and control all assets.
A major high-speed rail line linking the UK with continental Europe is an example of all the technologies working together. To ensure smooth operation, there are multiple substations along the high-speed rail line to ensure that electricity flows to the tracks at all times. The substations are connected through a SCADA software system that collects and interprets data from equipment along the line. Additionally, each substation is equipped with RTUs that execute commands from SCADA systems to ensure safe and reliable power flow.
The electricity landscape is rapidly evolving. Whether the challenge is to find mutually beneficial ways to integrate large amounts of renewable energy, local distributed energy or microgrids, digital substations and other smart grid technologies such as RTU-based ATS systems, it can provide power operators with the power they need to thrive The advantages.
Reviewing Editor: Guo Ting