Passive Harmonic Filters

Mirus, a specialized division of Federal Pacific, designs passive harmonic filters to mitigate current distortion at the source of non-linear loads. The Lineator family of harmonic filters addresses a wide range of applications, from standard variable speed drive (VFD) installations to systems requiring advanced performance, environmental durability, or enhanced system stability.

These series-connected filters ensure compliance with IEEE 519 standards while maintaining the highest levels of system efficiency and reliability without the use of complex power electronics.

Technical Overview

⸻ OVERVIEW ⸻

Passive harmonic filters provide a robust, cost-effective solution for protecting upstream electrical infrastructure from the damaging effects of harmonic distortion.

⸻ Applications ⸻

Typical Applications

The Lineator series is specified for critical systems where efficiency and long-term reliability are essential for managing non-linear loads.

A metal industrial electrical device with multiple sections, connectors, and circular components on the bottom, mounted on a metallic frame, isolated on a white background.
⸻ PASSIVE HARMONIC FILTER SOLUTIONS ⸻

Lineator AUHF

The Lineator Advanced Universal Harmonic Filter is designed for 6-pulse VFD applications requiring less than 8% THID performance. With over 100,000 units in service worldwide, the AUHF delivers proven reliability and IEEE 519 compliance.

⸻ PASSIVE HARMONIC FILTER SOLUTIONS ⸻

Lineator HP

The Lineator High Performance is an advanced model engineered to achieve less than 5% THID, matching the harmonic performance of active front-end (AFE) drives.

Three large electrical coils labeled A, B, and C with terminals marked 1, 2, and 3 are connected with thick black wires to six cylindrical components below, likely capacitors or fuses, in an industrial setting.
A close-up of a three-phase transformer with six large, labeled coil windings (A1, B1, C1, A3, B3, C3) mounted vertically in an industrial workshop setting.
⸻ PASSIVE HARMONIC FILTER SOLUTIONS ⸻

Lineator HP2

The Lineator HP2 is a passive harmonic filter purpose-built for EC fan applications, addressing the low DC bus capacitance challenges that cause instability with standard passive filters.

⸻ PASSIVE HARMONIC FILTER SOLUTIONS ⸻

Lineator ED

The Lineator Extreme Duty is specifically designed for harsh environments with high background voltage distortion up to 12% or high ambient temperatures.

Three large electrical coils labeled A, B, and C with terminals marked 1, 2, and 3 are connected with thick black wires to six cylindrical components below, likely capacitors or fuses, in an industrial setting.
The image shows the interior of an electrical transformer or panel, with large yellow coils, copper bus bars labeled A, B, and C, various wires, fuses, switches, and circuit components arranged neatly.
⸻ PASSIVE HARMONIC FILTER SOLUTIONS ⸻

Lineator SUHF (Single-Phase Universal Harmonic Filters)

The Lineator Single-Phase Universal Harmonic Filter is designed to mitigate harmonic distortion from single-phase non-linear loads, improving power quality at the panel or equipment level.

⸻ RATINGS ⸻

Ratings at a Glance

Characteristic

Lineator™ AUHF

Lineator™ HP

Lineator™ HP2

Lineator™ ED

Voltage Class

208 V–690 V

208 V–600 V

208 V–690 V

208 V–690 V

Input Current Distortion (THID)

< 8% at full load

< 5% at full load

< 8% at full load

< 8% at full load

Efficiency

> 99.0%

> 99.0%

> 99.0%

> 99.0%

Power Factor

> 0.95 (30% to 100% load)

> 0.98 (at rated load)

> 0.95 (at rated load)

> 0.95 (at rated load)

*The Lineator ED maintains the same harmonic mitigation performance as the AUHF while providing enhanced environmental durability. Performance may vary depending on system conditions.

Additional solutions, including the Inversine AUSF (Advanced Universal Sine-wave Filter), are available for unit-level, single-phase, and waveform conditioning applications.

⸻ PASSIVE HARMONIC FILTERS ⸻

Is a Passive Harmonic Filter Right for Your Project?

Determining the appropriate harmonic mitigation strategy depends on load variability, efficiency requirements, and the total harmonic distortion limits of your facility. The following table provides a direct comparison between Mirus’s passive and active filtration solutions.

Feature

Passive Harmonic Filter

Active Harmonic Filter

Mitigation Method

Series inductor/capacitor network

Parallel IGBT current injection

Operating Efficiency

> 99%

96%–97.5% (low-voltage)

Harmonic Spectrum

Full wide-spectrum mitigation

Up to 50th harmonic order

High-Frequency Noise

None (No supraharmonics)

Injects switching noise (> 50th)

Maintenance

Minimal (No fans or filters)

Periodic fan and filter service

Response Time

Instantaneous (Passive)

Real-time (< 1ms sensing)

Not sure which applies to your project?

⸻ RESOURCES ⸻

Documentation and Resources

Access technical specifications, installation manuals, and white papers relevant to harmonic filtration.

Filter By Product

Sinewave Filter Comparison

Sinewave Filter Comparison. A typical sinewave filter consists of a 5-12% impedance inductor L combined with a capacitor C (also may include.

The Modern Medical Facility-Hospital Environment

The Modern Hospital/Health Care Environment & Harmonics. Regional Sales Manager – South USA.

Using Lineator AUHF Harmonic Filter with Adjustable Speed Drive equipped with Bypass

31 Sun Pac Blvd., Brampton, Ontario, Canada L6S 5P6 Harmonic Filter. Adjustable Speed Drive equipped with Bypass.

Water and Wastewater Spotlight: A Single Phase Source Harmonic Solution for Three Phase Drive Applications

A SINGLE PHASE SOURCE HARMONIC SOLUTION. VFD and Harmonic filters to single phase service rating per the manufacturer’s instructions, since.

iFly Australia

MIRUS International will provide harmonic mitigation for Australia’s first dedicated wind tunnel facility for.

CNCE TS001 A6 (CNCE Typical Spec)

Treats 5th, 7th, 17th & 19th harmonics as well as the triplens (3rd, 9th & 15th).. reduce loading of neutral conductors, reduce neutral-to-ground voltage and lower harmonic distortion in 3-.

⸻ Additional RESOURCES ⸻
⸻ SUPPORT ⸻

Lifecycle Support

Mirus supports harmonic filtration with technical consultation and simulation tools to ensure optimal system performance and compliance.

⸻ Performance ⸻

Engineered for Performance

Mirus engineers passive harmonic filters with a commitment to energy efficiency and real-world performance. Unlike conventional filters that can fail under voltage imbalance or background distortion, the Lineator is engineered to maintain its mitigation effectiveness in non-ideal grid conditions.


Our passive design eliminates the failure modes associated with power electronics, providing a lower total cost of ownership and a service life that typically matches the life of the connected equipment.

⸻ CONNECT ⸻

Discuss Your Application Requirements

Contact our team to identify the appropriate passive filter configuration for your harmonic mitigation and operational requirements.