PFC-FT2

Capacitor/Reactor Modules
Iron Core Reactors: Each PFC-FT2 includes specially designed, iron core reactors used in series with the capacitors. Each reactor is manufactured under tight control tolerances to ensure quality, constructed with a laminated, low-hysterisis loss iron core, copper windings, precision-controlled air gaps and Class H insulation (1800C).

Available reactor types
Inrush-only: Reactors designed to limit the inrush current which may develop in the capacitors during power up, avoiding damage to switching elements, fuses and capacitors;
De-tuned: Prevent resonance conditions by shifting the capacitor/network resonant frequency to below the first dominant harmonic (usually the 5th);
Tuned: Designed to absorb a majority of the dominant harmonic(s), usually the 5th and/or 7th.

Capacitors
PFC-FT2 features MKP-type capacitors that are low-loss (0.25W/kVAr) and housed in cylindrical aluminum casings. The MKP-type capacitor is a metallized polypropylene film capacitor featuring self-healing properties and an overpressure tear-off fuse. To reduce the effects of electrical and thermal overload and extend operating life expectancy, the capacitors are connected during zero-current crossing and operated in a time-sharing mode (SCAN).

System Technology

Capacitor Group Switching The PFC-FT2 switches capacitor groups on and off using state-of-the-art electronic switches. The connection and disconnection of capacitors occur precisely at zero-current crossing. This smooth connection avoids transient effects typically created by electromechanically switched power factor correction (PFC) systems, extending the life expectancy of the PFC-FT2 dramatically.

SCAN Mode The PFC-FT2 is equipped with a unique SCAN feature that protects capacitors from exploding and contributes to longer life expectancy by reducing over-current and minimizing capacitor heating. The electronic switching element (unlimited operations) connects one capacitor group simultaneously as another group is disconnected. This operation occurs every few seconds, engaging each capacitor group in turn, with total compensation unchanged. This results in mean current reduction due to lower duty cycle (engagement time to cycle time). Together with the unique reactor design, temperature rise of the reactors is substantially reduced and the potential for cabinet overheating is minimized.

Consistent Capacity Conventional electromechanical capacitor banks suffer from an ongoing cumulative reduction in capacity due to the effect of transients during connection and disconnection. This can be especially detrimental in tuned and detuned electromechanically switched systems where changes in the ratio between the capacitors and reactors shift the resonant frequency. This scenario can cause resonance, which can cause extreme damage to equipment in the facility. The PFC-FT2 prevents this scenario, resulting in longer system life, lower maintenance costs and more consistent harmonic filtration over time.

Ideal PFC Control Using exclusive automatic control algorithms and rapid electronic switching, total acquisition time (complete compensation of reactive current) is achieved in 2/3 cycle typical (50Hz = 13.3 ms; 60Hz = 11.1 ms), irrespective of the number of steps required. The power factor is controlled very accurately through an advanced open and closed-loop control & measuring system that uses information from all three phases, as well as accounts for the effect of harmonics (1 through 63). Minimum, maximum and average power factor modes, as well as threshold levels, can be selected for perfect compliance with specific network requirements. The PFC-FT2 includes a unique solution for line-to-line loads, in which it calculates a transformer’s internal currents and compensates accordingly. Third party measurements have proven the PFC-FT2 to be the ultimate solution to offer precise compensation for voltage drop and flickering.

Fast and Accurate Measurements The PFC-FT2 controller uses FFT (Fast Fourier Transform) analysis of all phases each cycle. Power information, system status and detailed logs of events are displayed on a large backlit graphic LCD screen, or via communication using the user-friendly PowerIQ software. PowerIQ Measurement & Analysis Software (optional) This Windows-based software can display the system's status, measurement results and real-time data.