These days, it is not uncommon to find non-linear loads in a number of electronic supplies and devices. Now, the main downside of this is the propensity for an increase in harmonic distortion. This, in turn, can result in a number of unpleasant side effects. These include unsystematic breaker tripping, transformer and distribution equipment overheating, and even failure of sensitive equipment. Fortunately, of course, there are a few strategies that you can utilise to control harmonic distortion and prevent these events. Here is what you can try:
Reduce the Harmonic Currents in Loads
The first thing that you should understand is that there are limits as far as reducing harmonic distribution on the current load equipment. This is because most electronic power converters and arcing devices have set characteristics that can’t be manipulated. What you can do, however, is to utilise transformer connections in three-phase systems. The fifth and seventh harmonics can be greatly reduced by phase-shifting half of the 6-pulse power converters in a plant load by 30 degrees. You can then rely on delta-connected transformers to block the flow of zero-sequence harmonics while grounding transformers can shunt these harmonics off the line.
Utilise Line Filters
The next thing that you can try is to include line filters on the input side and output side of a VSD. Now, there are a number of advantages to this solution. For one thing, it is a cost-effective option that is also incredibly durable. As a result, it is well-equipped to absorb any kind of line disturbances, effectively controlling harmonic distortion in the process. This solution is especially effective in reducing the potential for damage done to sensitive equipment. It should be noted, however, that these advantages are a direct result of the quality of line filters. So, if you want to make certain that the product you are choosing is capable of all these performances, you should make certain that you choose a brand such as MTE. This way, you can be certain of the improvements.
Cut Down the Response to Harmonic Distortion
There are also quite a few things that you can do to alter the system’s adverse responses to harmonic distortion. For instance, you can add a reactor as it is capable of detuning the system. This reactor needs to be included between the capacitor and the supply system source. On the other hand, if you are looking to minimise both cost and effort, then you may want to consider simply changing the size of the capacitor. For those that are searching for a truly economical intervention, you may want to reduce the capacitor altogether. Nonetheless, you should be warned that by doing so you will have to contend with a power factor penalty, higher losses, and a lower voltage to boot.
As you can see, there are a few options to rely on, when trying to control harmonic distortion. It is up to you to think about your current operations and determine which solution is best. Then, it is simply a matter of implementing one that works for you and your facilities.
