Tagged: Power Factor Correction

Enabling a seamless Champions League final in Istanbul with Active Harmonic Filter

Service Partner: Wömner Power Quality Solutions
Location:Istanbul, Turkey
Industry: Sports Venue
Timeline: 2020-2023

Background

When Istanbul was selected to host the 2020 Champions League Final, the Turkish Football Federation contracted Renaissance Construction to renovate the city’s Olympic Stadium as the venue. Although the final was delayed until June of 2023 due to the pandemic, the work proceeded as scheduled and Wömner Power Quality Solutions, Comsys’s partner in Istanbul, was selected to ensure that no power quality issues would disrupt the prestigious event.

Challenge

Predicting what could go wrong during the final is difficult for various reasons. Firstly, power is peak during games, which take place only two or three times a month at most. Secondly, the stadium is supplied from several medium voltage (MV) substations, each having two backup transformers making the measurement of energy consumption complex due to the uncertainty of not knowing which of the three transformers is being utilized. Thirdly, a total of 25 km of MV underground cable creates 180 kVAR of capacitive power per hour. During game time reactive power is balanced, but on no load condition capacitive power is there and because it is on MV level it cannot be easily measured due to the position of the meter, which is 6 km away. And finally, two large scoreboards with a lot of power electronic equipment were installed for the final, creating harmonics.

The customer’s main priority was on harmonics and trips due to these, as well as on reactive power management. Normally, other power quality issues are quite small.

Solution

A total of seven Comsys ADF P100N active harmonic filters were installed by Wömner; two at each of the three main substations for the stadium, and one additional unit at a smaller utility substation.

Result

Since the filters were installed in early 2020, the customer has experienced no problems due to capacitive penalties and game nights have been safe and secure. The Active Harmonic Filter technology is successfully compensating harmonics and preventing capacitive penalties.

Active + Passive = Hybrid

Active Harmonic Filters are becoming cheaper and very competitive compared to other active mitigation solutions such as Active Front End, which we explained here.  In some applications that are not too dynamic, a passive harmonic filter makes perfect sense to reduce the investment. A combination of active and passive filters can be the best solution to reduce the investment cost while still being able to cope with dynamic loads. In such an application the passive harmonic filter focuses on the dominant harmonic component.  This solution is currently used by for example the German auto industry in their production lines.

PQ Nosswitz, a German power quality solutions firm, devised a system to allow a flexible combination of active harmonic filters and passive harmonic filters to enable the most flexible and cost efficient solution for every project.

 

Active Harmonic Filter Application in Ba Na Hills, Vietnam

Here is a great showcase of the effects of applying active harmonic filters on a cable car installation made by Power More in Vietnam. Ba Na Hills Mountain Resort are holders of three Guiness Records – Longest single rope cable car system, Longest distance between stations and Heaviest cable roll. For Ba Na Hills, power quality is a question of safety and service quality. With total harmonic distortion 5 times higher than the national regulated level, Ba Na Hills were facing several problems.

  • Station to station communcation was interrupted
  • Power factor penalties
  • Damaged PFC capacitor units
  • Inerference with PFC controller
  • Reduced motor effeciency in generator mode to 50%

Applying ADF Power Tuning active filters from Comsys to battle both power factor correction and harmonic filtering resulted in:

  • Eliminated risk of PFC failures
  • Eliminated power factor penalties
  • Increased motor efficiency to 100%
  • Improved cable speed

Harmonics and Notches in Dynamic Test Load

Active Harmonic Filters Improve Dynamic Test-Bed

A major pioneer in the manufacturing industry caused problems on the power supply network with their dynamic test bed. Here, an installation of the right combination of active harmonic filters now compensates harmonics up to the 100th order with great results. Both harmonics and voltage notches are reduced to enable top performance of the equipment.

Case Background

Dynamic test load before harmonics compensation

Before Compensation:
– Very high distortion on current
– Note the severe voltage notches

The test benches, owned by the development department of a major European production plant, are used to test components in the development phase. Varying test conditions can be programmed, which gives the test bench very dynamic properties.

Harmonics Compensation Challenge

The same transformer is connected to two parts of the test bench. With a very dynamic load whose load current amplitude can change from zero to maximum in approximately 100 ms, it was impossible to run both parts of the test bench simultaneously. The voltage notches of up to 25% in combination with very high harmonic disturbances prevented this. This caused serious delay in the testing facility as well as exceeding the limits in EN61000-2-4.

Active Harmonic Filters – the Solution

To solve the power quality issues, several active harmonic filters were installed to compensate the disturbances. Two 200/480V filters were installed together with one 100/480V filter that in combination compensate all frequencies up to the 100th harmonic order. The first two filters can be used to compensate lower harmonics while the third compensates for higher order harmonics and interharmonics. The three units were configured to share the

load with the 100/480V filter working on higher orders only. This resulted in extremely short response times and considerably lowered load disturbances.

Dynamic load after harmonics compensation

After Compensation:
– Very low distortion on both voltage and current
– Note the reduced notches

Harmonics Compensation – the Result

Thanks to the active harmonic filter installation, voltage notches could be reduced to 10%. In addition, harmonics were lowered to the required level stipulated in EN61000-2-4. Now, both test benches can be run simultaneously without any of the problems caused by poor power quality.