Comsys has released a application note explaining the detailed advantages of using central filtering of many drives rather than installing separate low harmonic drives. A central active harmonic filter is often the cheapest and most efficient answer to maintain code compliance.
Read the report here: Global-vs-Local-Compensation_Application_Note
Schaffner launches an updated version of its rack mounted active harmonic filter with higher efficiency and heat tolerance as we understand.
Schaffner reports:
The modular design of ecosine active sync always allows a suitable filter size to be supplied and, in addition, the 60 A modules can be easily fixed to the wall or integrated into system control cabinets. Simply slide in and wire up – a filter from up to 300 A per cabinet is ready.
Comsys has supplied Active Harmonic Filters to multiple offshore supply vessels. Bourbon Offshore, one of the biggest operators of offshore service vessels is using active filtering on their Evolution series of MPSVs. Filtering is employed on the main busbar to comply with class regulations. For a full report on the project and the result see here:
Bourbon Offshore Case by Comsys
The new PHF generation “ecosine evo” is designed for the most demanding harmonic mitigation tasks with front-end 6-pulse rectifiers.
Even partial load situations causing harmonic currents can be effectively mitigated. The introduction of a modular system allows the Ecosine Evo passive harmonic filter to deliver optimally tailored solutions for your particular installation. The solution is easily adapted by simply plugging in the suitable module where needed. For more information, watch this:
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.
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.
Applying ADF Power Tuning active filters from Comsys to battle both power factor correction and harmonic filtering resulted in:
Active Filtering just got simpler with Sensorless Control
Comsys has released a new solution for controlling the Active Harmonic
Filter. The sensorless active filter control reduces the cost and
complexity of the system as it does not require any current transformer
sensors.
In this case study they describe the retrofit on a small diesel
electric powered oil tanker, Fox Luna. The sensorless active filtering
approach is well equipped for protecting sensitive loads from dirty grids.
In this case study of the Luzern Conference Center in Switzerland, Schaffner demonstrate the full utility of the active harmonic filter application. The active filters are distributed throughout the building to compensate not only harmonics but also power factor correction as well as load balancing.
Leave it to the Swiss to adapt to multifunctional tools.
Vacon joins Danfoss as the second tier 1 drives manufacturer to integrate an active harmonic filter with a drive to lower harmonics. Vacons stand-alone NXC range previously offered 12 pulse as well as active front end drive solutions.
The Low Harmonic NXC was recently shown at a large exhibition in Sweden and is reportedly offered on a project by project basis but will become a standard offering in the near future. The system shown, verifies the smaller foot print and weight of the Active Filter drive system compared to the more common Active Front End drives. The active filter NXC also has a lower power loss, which is becoming more important as the EN 50598-2 standard is introduced.
Active Harmonic Filters 