Power filters are electronic circuits designed to locate and eliminate surges, harmonic transient currents, spikes, and other unwanted signals in power distribution systems and electrical equipment such as computers, television sets, and other devices. There are many different types of power filters. Examples include power line filters, power supply filters, microwave filters, and harmonic line filters. A power line filter removes impurities and artifacts from an alternating current (AC) that energizes components. In addition, power line filters protect equipment from potentially damaging voltage surges. A power supply filter helps reduce conducted noise to acceptable limits for equipment. A microwave filter is used to eliminate unwanted frequency components in the output from microwave transmitters. Microwave filters are typically inserted between a power amplifier and an antenna. Higher harmonics generated by phase control firing of thyristors require the implementation of a harmonic filter, so that the harmonics do not break through the AC distribution system. Harmonic filters require tuning to line and load conditions. Other power filters are also commonly available.

There are several ways in which power filters function. A power line filter protects components and enhances system performance. Some examples of power filter specifications include filtered digital outlets, filtered analog outlets, 210 joules/18,000 amperes surge capacity, and 1800 Watts/15 Amps power/current capacity. Harmonic filters utilize and AC variable frequency and variable torque drive applications. Harmonic filters will meet the guaranteed maximum levels of total harmonic current distortion (THID) all the way from no load to full load. Additionally, a harmonic filter will not cause power system resonance or attract harmonics from other non-linear loads. When utilizing a microwave filter, it is necessary to estimate the drift of the passband frequency due to thermal expansion due to high power loads, but also possibly from harsh environmental conditions. Power filters can be designed and manufactured to meet most industry specifications.

Power filters are electronic circuits designed to locate and eliminate surges, harmonic transient currents, spikes, and other unwanted signals in power distribution systems and electrical equipment such as computers, television sets, and other devices. There are many different types of power filters. Examples include power line filters, power supply filters, microwave filters, and harmonic line filters. A power line filter removes impurities and artifacts from an alternating current (AC) that energizes components. In addition, power line filters protect equipment from potentially damaging voltage surges. A power supply filter helps reduce conducted noise to acceptable limits for equipment. A microwave filter is used to eliminate unwanted frequency components in the output from microwave transmitters. Microwave filters are typically inserted between a power amplifier and an antenna. Higher harmonics generated by phase control firing of thyristors require the implementation of a harmonic filter, so that the harmonics do not break through the AC distribution system. Harmonic filters require tuning to line and load conditions. Other power filters are also commonly available.

There are several ways in which power filters function. A power line filter protects components and enhances system performance. Some examples of power filter specifications include filtered digital outlets, filtered analog outlets, 210 joules/18,000 amperes surge capacity, and 1800 Watts/15 Amps power/current capacity. Harmonic filters utilize and AC variable frequency and variable torque drive applications. Harmonic filters will meet the guaranteed maximum levels of total harmonic current distortion (THID) all the way from no load to full load. Additionally, a harmonic filter will not cause power system resonance or attract harmonics from other non-linear loads. When utilizing a microwave filter, it is necessary to estimate the drift of the passband frequency due to thermal expansion due to high power loads, but also possibly from harsh environmental conditions. Power filters can be designed and manufactured to meet most industry specifications.

Power filters are used in many applications. Some examples include adjustable speed motor drives, uninterruptable power supplies (UPS), welders, battery chargers, mission critical facilities electronic welders, water treatment facilities, and elevator drives. Power filters should adhere to electromagnetic interference (EMI) and radio frequency interference (RFI) emissions standards.