Mitigating Harmonics and Inrush Currents in Power Systems #
Series ReactorsOverview #
In recent years, the widespread use of industrial semiconductor devices has led to an increase in harmonics within electrical circuits. These harmonics can cause various failures in power systems and present challenges such as frequent inrush currents, especially in applications involving automatic power factor regulators (APFR).
Series reactors are an effective solution for mitigating these issues. By integrating series reactors into the circuit, it is possible to limit both harmonic currents and inrush currents to capacitors. This not only helps to extend the operational life of capacitors and electromagnetic contactors but also enhances the overall reliability of the power system.
Key Features #
- Harmonic Suppression: Series reactors are designed to inhibit high-order harmonics, reducing the risk of power system failures.
- Inrush Current Limitation: They effectively limit inrush currents during frequent switching, particularly in APFR applications.
- Extended Equipment Life: By controlling current surges, series reactors help prolong the lifespan of capacitors and electromagnetic contactors.
Technical Specifications and Performance Standards #
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Applicable Standards:
- CNS 9094
- JEC-182
- JEC 2210
- IEC 60289
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Class of Insulation and Temperature Rise:
- Dry type: Class H, coil temperature rise below 120°C (resistance method)
- Oil type: Class A, coil temperature rise below 65°C (resistance method), oil temperature rise below 65°C
- Cast resin type: Class F, coil temperature rise below 95°C (resistance method)
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Installation:
- Dry and oil types are suitable for indoor use
- Oil type can be used for both indoor and outdoor applications
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Ambient Temperature:
- Operating range: -20°C to +45°C (24-hour average temperature below 35°C)
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Capacity Tolerance:
- -5% to +10%
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Maximum Permissible Current:
- Up to 120% of rated current (effective value of synthetic current, with the 5th harmonic current less than 35% of the fundamental current in the reactor circuit)
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Rated Short-Time Current:
- 25 times the rated current for 2 seconds
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Voltage Withstand (AC Test Voltage):
Rated Voltage (U) AC Test Voltage (kV) U ≤ 0.22 2 0.22 < U ≤ 1 4 1.1 < U ≤ 3.3 10 6.6 16 12 28 24 50