Standards governing distiortion parameters in the electric grid such as IEEE 519, G5/4, EN 61000, EN 50160 and D-A-CH-CZ among others most often require voltage harmonic distortion to be below 5-8%. These are all recommended, not obligatory practices.
Although adherence to standards such as IEEE 519 is not obligatory, more and more utilities and other parties of interest are using these standards as a benchmark to place demands on their customers. This is a way for them to be able to guarantee disturbance free delivery on their end. It is also used as a part of an active environmental agenda to show a decreased energy usage and reduced energy costs for many energy intensive processes.
One way to meet the new requirements is to simply reduce the harmonics to an acceptable level. Many modern active harmonic filters can pinpoint the harmonic orders that are contributing, and the compensation power can be optimized to meet the requirements in the most cost efficient way.
The modern Active Harmonic Filter is one of the most efficient harmonic solutions the market today. Filters are commonly available in a 208 – 480V version and a 480 – 690V. The Active Harmonic Filter can be combined with 6 pulse drives and will be placed in parallel with the load, minimizing the need of compensation power to 20 – 30 % of the load. The parallel placement will also ensure the redundancy in the design, which is a major advantage in a critical applications. Modular solutions, which are now more commonly available gives a dynamic and agile solution to work for future improvements to existing machinery. This is all in keeping with the spirit of standards such as the IEEE 519 toward a sustainable energy future.