Harmonic Filtration

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Why you need to eliminate harmonics in your electrical systems:

Harmonics are a type of electrical pollution which results in distorted voltage and current wave forms. This negatively impacts your electrical systems by increasing the root mean square (RMS) of the voltage and current, lowering the power factor and deteriorating the quality of the electrical supply. Harmonics in your electrical systems could lead to:

  • Increased energy consumption, thus increased operating costs
  • Poor power quality & efficiency
  • Reduced equipment lifespan & increased maintenance
  • Interference with communication systems & other electronic equipment
  • Reduced power system capacity, reducing reliability
  • Tripped circuit breakers, blown fuses
  • Increased neutral current, leading to overloaded systems & overheating, becoming a potential fire hazard
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    How to get rid of harmonics

    Depending on the harmonic content of an electrical installation, we use either active or passive harmonic filters. We have found that these methods are the most effective and cost-effective.

    Alpha Power is an expert in both power factor correction and harmonic filtration. With over 30 years’ experience, we have successfully helped our clients with solutions across a range of industries and applications.

    Our harmonic filters eliminate or reduce to acceptable levels, distortions caused by harmonics.

    Our harmonic filters

    Alpha Power’s harmonic filtration filters are available in a passive or active range to best suit your application’s requirements. We can conduct a detailed analysis of your network to determine which filter will suit your application best.

    There are two main types of harmonic filters: passive and active. Passive filters use a combination of capacitors and inductors to filter out harmonic frequencies, while active filters use power electronics to actively cancel out harmonics in real-time.

    Not sure which filter you require? We will figure it out for you! Contact us!

    Here are a few key attributes of each filter:

    Active harmonic filtersPassive harmonic filters
    More precise harmonic correction compared to passive filters since they tend to respond quickly to changes in harmonic levelsNo maintenance is required and they typically have a longer lifespan compared to active filters.
    Typically, more expensive than passive filters and require more maintenance.Lower cost and equipment specific.
    Handle higher levels of harmonic distortion than passive filters.Contains no electronic components, making them less vulnerable to general failures and failures caused by power surges.
    Need to be installed in well-ventilated rooms and generate a fair amount of noise (up to 65 dB).No power source is required to function, making them ideal for remote locations.

    Industries we serve

    Our harmonic filters benefit industries that use non-linear loads such as variable frequency drives, soft starters, LED lighting, and uninterruptible power supplies that create harmonic distortion in the electrical system.

    The following is a list of industries we serve:

    1. Data Centres & IT
    2. Manufacturing
    3. Healthcare
    4. Energy & Utilities
    5. Retail & Commercial Buildings
    6. Hospitality & Leisure
    7. Mining & Metals
    8. Chemical & Petrochemical

    The two major contributors to harmonics include electronically controlled equipment and multiple electronic devices connected to your system. The nature of these electronics causes extremely quick pulses, creating a sine wave that becomes non-linear in shape. The end result affects the operation and longevity of your inter-connected systems and equipment.

    By installing harmonic filtration units, these industries can improve power quality, prevent equipment damage, increase efficiency, and reduce operating costs!

    Frequently Asked Questions

    Harmonics are a type of electrical pollution that can negatively impact your electrical system. They are currents or voltages whose frequencies are an integer (whole number: zero, or positive or negative number) multiple of the fundamental frequency. They occur due to a distortion in an electrical network created by non-linear electrical devices such as variable speed drives, DC drives, soft starters, UPS, etc.

    When harmonic currents flow through passive harmonic filters, they are absorbed and dissipated as heat, which improves power quality and reduces the risk of damage to electrical equipment.

    They typically consist of passive components such as inductors and capacitors that are connected in a specific configuration to cancel out harmonic frequencies.

    These filters are wide-spectrum harmonic current sources capable of generating a large range of harmonic currents and use very high-speed switching devices like IGBTs, ensuring a response time of a few milliseconds. They produce counter-harmonic currents in phase opposition to that produced by non-linear loads, and these generated currents are injected into the system in real time, ensuring effective cancellation of all harmonics present in the network.

    They typically consist of a high-performance CPU which controls IGBT’s.

    A total harmonic distortion (voltage) or THD(V) of 2.5% and a total harmonic distortion (current) or THD(I) of 15% are usually considered safe levels.

    Depending on the severity and source of the harmonic distortion, active or passive harmonic filters can be installed to reduce the harmonic levels present in a system. Contact us and one of our experts will get back to you.

    Yes, Alpha Power Solutions can measure the harmonic levels in your electrical systems on your premises. Get started with solutions from Alpha Power!

    Prevent equipment malfunction, shutdown & premature failure with harmonic filtration equipment from Alpha Power Solutions.
    Contact us 010 040 3132 or complete the enquiry form.

    I want to reduce my power/electricity cost

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