Rising Power quality (PQ) Concerns at Airports

Published On: Sep 30, 2019

The presence of large nonlinear loads in airports, (e.g., 400 Hz ground power units, Air Handling Units, computational systems and servers, and the growing use of electric vehicle battery chargers) creates PQ issues. The PQ can further deteriorate power delivery and develop energy consumption concerns for electric power providers and airports.

INTRODUCTION

Electrical downtime is a suicidal for airports. As Airports undergo transformation to deliver ‘customer experience’ even the smallest power disruption is being amplified by dissatisfied customers. And Customers here include not just the passengers but a vast array of vendors and service providers who are partners in delivering the ‘airport’ experience to the travelers. Continual and quality power supply to various mission-critical systems, including runways and control towers at the airport is not optional. Add to it the increasing number of commercial and business facilities in larger airports, the more they have started to resemble shopping malls with a wide variety of stores and restaurants. From the power usage and impact of power quality of these multitude of loads and its impact on core operations of an airline, the power management at the airport is getting more and more complex.

The cycle times for airport operations are also expected to be reduced with increased automation of the tasks. This in turn poses new challenges in terms of Power Quality for the electrical network. It’s about time, Airports design monitoring systems that provide quality and energy consumption information and predict failures or power disruptions before they occur in order to maintain uninterrupted operations.

IMPORTANCE OF PQ AT THE AIRPORTS

The average passenger traffic at the world’s top 20 busiest airports grew by over 5% in the previous year. But these airports experienced much bigger expansion across a diverse range of systems. Starting from baggage handling, MROs, security and surveillance, runways, parking, cargo, fuel depots, shops and restaurants to sewage, HVAC and other utility operations – if there is one thing that keeps all these systems seamlessly running at the airports it is ‘quality’ power.

…power is money!
Well, usually, airlines would say otherwise – ‘money is their power’. But at the airport, the electrical power has the power to drain a lot of money – not just for the airlines, but airport operations and passengers as well. For instance, Atlanta’s Hartsfield-Jackson International Airport power outage is estimated to cost the Delta Air Lines an estimated loss between $25 to $50 million. Globally, Airports are facing increasing instances of outages and equipment shutdown.

An electrical substation fire caused a major power outage at Hartsfield-Jackson Atlanta International (ATL), the world’s busiest airport. It took several days for the operations to return to normal on the ground, and the National Airspace System had to cancel or divert thousands of flights.
Amsterdam’s Schiphol airport — Europe’s third busiest — was temporarily closed in April when a large power outage hit all operations.
McCarran International Airport in Las Vegas, Nevada, experienced an outage in mid-June resulting in a ground stop, delayed flights, and baggage and screening system shutdowns.
Hamburg airport, one of Germany’s busiest, lost power in early June and was forced to close, leading to flight cancellations that affected 30,000 passengers.

The situation in India is no different. Blame game over IndiGo server & flights’ chaos after power outage –

A power failure at the Airport in Pune allegedly triggered an outage in Indigo’s (one of India’s largest airlines) IT systems.
The AAI authorities claimed the flight disruptions were because of Indigo’s system failures
More than 10 flights were delayed and restoration took about an hour
A source working as ground staff said power outage was a frequent affair at the airport with power suddenly goes off at the terminal building for 15-20 seconds

In early 2011, the IGI Airport in Delhi faced a five-hour power cut

The power disruption had brought operations at IGI airport’s swanky T3 terminal to a standstill, delaying around 80 domestic and international flights.
The T3 terminal, had just completed its first anniversary, plunged into darkness between 1:25 am and 5:45 am due to problem in one of the tripping of transformers that supplies power to the terminal owing to an electrical fault.
Following the tripping, the power supply to entire building was disrupted and operations of baggage handling system, passenger boarding (aero) bridges, piers, escalators and travellators’ came to a standstill.

Improved airport power reliability and availability is the only way to avoid these unplanned downtime issues and improve the customer experience. Airports are rising-up to address this issue, rather steadily, and also in many diverse approaches. In this blog we review some of the key issues that airports face in terms of Power Quality and of how these have been addressed by examples from around the world.

MANAGING PQ IN EXPANSION OF AIRPORTS

Worldwide, the transportation terminal projects posted a year-on-year increase of 61% in 2018 – as per the ConstructConnect’s construction industry snapshot. This included growth in terminals, additional runways and related infrastructure. Almost all the world’s top airports have major expansion plans.

It is estimated that in the USA alone the spend on airport expansion in near future could be appox. $70 b, across 50 projects.
In India, the Govt. plans to launch 100+ new airports to boost the connectivity between Tier II and Tier III cities, as well as modernise the aging facilities in existing airports.

But expansion of facilities needs perhaps more planning and care than a greenfield airport project. The Facilities and maintenance staff have to overcome a number of challenges in order to integrate the power infrastructure capacity needed to accommodate future long-term growth.

What is the potential?
Emergence of devices that respond and automatically resolve PQ issues in the electrical systems provides a huge potential given the unpredictable nature of PQ events. Various AI techniques can be used as per their strength and limitations to build such devices and apply rapid intelligence in real-time. Given below are some of the most popular AI techniques used in case of power system reliability.

Continuous monitoring of key electrical parameters that allows visibility to power data is the first step to improving the PQ. This must be followed with data aggregation and centralized tracking of real-time power conditions. Together, the continuous PQ monitoring tools allow for detailed analysis of power network reliability so that issues can be quickly identified, isolated and resolved. The Facility staff gains with a proactive insight for managing their electrical systems and the condition of their assets.

PQ CONCERNS IN GROUND SUPPORT EQUIPMENT

The increased use of electric ground support equipment (GSE) can adversely affect the quality and the reliability of the electric power system of an airport. The growing use of electric vehicle battery chargers in Ground Support Equipment is a non-linear load and therefore a concern for the airports. Studies that examine the power quality impacts of GSE charging systems on the airport electric distribution system point to overloading of the distribution transformer and/or switchgear as a key concern.

Further, higher THD are likely to be observed if the chargers do not match the performance guidelines based upon IEC 61000-3-4. Mitigation of issues could be complex and might need involvement of multiple agencies to resolve the root causes.

POOR PF IN RUNWAY LIGHTING SYSTEMS

In 2018, the operations at the Heathrow airport were disrupted due to a technical issue in the runway lighting systems.
In May 2018, the runway at Dabolim Airport in Goa had to be closed for several hours due to a fault in runway lighting system. This is a repeat of similar incident some months back. Several flights were diverted at the last-minute creating disruption in schedule and huge inconvenience for the passengers.

Runway lighting systems in airports tend to have a relatively poor PF. The PF could be as low as 0.4 and must be corrected in order to seamlessly switch the runway lights to generator.

Airports are also increasingly shifting to LED light systems that allow for a significant reduction in operating costs offer relatively longer life and lower maintenance costs, coupled with proven brightness and safety for pilots. However, high concentration of LED lights are also considered notorious due to increased harmonics and inrush currents. Both these lead to poor PQ for the electrical network in absence of appropriate mitigation devices.

PQ – THE BLACKBOX OF AIRPORT POWER SYSTEMS

Several systems are affected by poor PQ. In the discussion above, we have highlighted only a few examples to demonstrate the case for improving PQ. There is no doubt about how the PQ of the airport power systems gives a deep insight into the health of electrical network which is not visible otherwise. Similar to the blackbox of the aircraft, PQ parameters can specifically indicate the deep-rooted problems in the electrical network of the airport.

To address PQ concerns, typically, airports have to work on multiple fronts. A very broad outline of the activities includes:

Enhancing effectiveness of preventive and predictive maintenance
Improving both preventive and predictive maintenance techniques for power generator and distribution systems
Establishing an integrated automation system that proactively monitor and fast respond to power outages
Optimise operational costs on electrical power maintenance and long-term device procurement
Assessing the lightning risks and improvements of lightning protection systems
Compliance with numerous international standards for strict power supply and lighting provision
Analytical studies for power quality analysis, power surveys, thermal imaging, load bank testing, training, refurbishment and midlife upgrades, engineering
Several Airports are considering going off-grid to ensure complete control over power systems, own a more reliable source of power, and a better backup system

On the people side, it requires close and continual co-ordination between several roles to improve the PQ. Starting from Airports’ technical services, Power Supply Maintenance, Electrical engineering departments, Aviation Authority, Mechanical engineering, EHS and Facilities department, everyone must be on the same page. PQ provides a strong and common reference point to all the agencies, vendors and equipment manufacturers to improve the health of the airport power systems.