Reactor (Inductor): Pahayag ug mga Uri
Ang reactor, gikataas usab og inductor, mao ang nag-generate og magnetic field sa kalibutan sa palibot samtang adunay kasinatong nga nag-usbong sa usa ka conductor. Busa, anang tanang conductor nga adunay kasinatong natural nga adunay inductance. Apan, ang inductance sa usa ka straight conductor gamay ra ug nag-produce og dili matibay nga magnetic field. Ang praktikal nga reactors gibuo sa pag-winding sa conductor sa usa ka solenoid shape, gikataas usab og air-core reactor. Aron mapadako pa ang inductance, isulod ang ferromagnetic core sa solenoid, nahimong iron-core reactor.
1. Shunt Reactor
Ang unang modelo sa shunt reactors gigamit sa full-load testing sa mga generator. Ang iron-core shunt reactors nag-generate og alternating magnetic forces sa pagitan sa segmented core sections, resulta niania ang noise levels tipikal nga 10 dB mas taas kaysa transformers sa equivalent capacity. Ang shunt reactors nag-carry og alternating current (AC) ug gigamit aron kompensahan ang system capacitive reactance. Kasagaran sila giconnect sa series sa thyristors aron mahimo ang continuous regulation sa reactive current.
2. Series Reactor
Ang series reactors nag-carry og AC current ug giconnect sa series sa power capacitors aron makabuo og series resonance circuit para sa steady-state harmonics (e.g., 5th, 7th, 11th, 13th harmonics). Ang typical nga series reactors adunay impedance values nga 5–6% ug gisulti nga high-inductance types.
3. Tuning Reactor
Ang tuning reactors nag-carry og AC ug giconnect sa series sa capacitors aron makabuo og series resonance sa specified harmonic frequency (n), resulta niania ang absorption sa atong harmonic component. Ang common nga tuning orders mao ang n = 5, 7, 11, 13, ug 19.
4. Output Reactor
Ang output reactor limita ang capacitive charging current sa motor cables ug restricts ang rate sa voltage rise sa motor windings hangtod sa 540 V/μs. Kasagaran kini required samtang ang cable length sa pagitan sa variable frequency drive (VFD) (4–90 kW) ug ang motor lisud sa 50 meters. Ito usab mag-smoothen sa VFD output voltage (reducing switching edge steepness), minimizing disturbances ug stress sa inverter components sama sa IGBTs.
Application Notes for Output Reactors:
Aron padak-on ang distance sa pagitan sa VFD ug motor, gamita ang thicker cables sa enhanced insulation, kasagaran non-shielded types.
Features of Output Reactors:
Suitable for reactive power compensation and harmonic mitigation;
Compensates for distributed capacitance in long cables and suppresses output harmonic currents;
Effectively protects VFDs, improves power factor, blocks grid-side interference, and reduces harmonic pollution from rectifier units to the grid.
5. Input Reactor
Ang input reactor limita ang voltage drops sa grid side sa panahon sa converter commutation, suppresses harmonics, ug decouples parallel converter groups. Ito usa limita ang current surges resulta sa grid voltage transients o switching operations. Sa panahon ang grid short-circuit capacity sa VFD capacity ratio lisud sa 33:1, ang relative voltage drop sa input reactor dapat 2% para sa single-quadrant operation ug 4% para sa four-quadrant operation. Ang reactor mahimo molihok samtang ang grid short-circuit voltage lisud sa 6%. Para sa 12-pulse rectifier unit, gikinahanglan ang line-side input reactor sa least 2% voltage drop. Ang input reactors gi-usab sa industrial ug factory automation control systems. Installed sa pagitan sa power grid ug VFDs o speed regulators, iya sila suppress surge voltages ug currents generated niining devices, significantly attenuating higher-order ug distorted harmonics sa system.
Features of Input Reactors:
Suitable for reactive power compensation and harmonic filtering;
Limits current surges caused by grid voltage transients and switching overvoltages; filters harmonics to reduce voltage waveform distortion;
Smoothes voltage spikes and rectifier commutation notches in bridge circuits.
6. Current-Limiting Reactor
Ang current-limiting reactors kasagaran gigamit sa distribution circuits. Giconnect sila sa series sa feeder lines branching sa same busbar aron limita ang short-circuit current ug maintain ang bus voltage stability sa panahon sa faults, preventing excessive voltage drops.
7. Arc Suppression Coil (Petersen Coil)
Widely used in resonant grounded systems at 10kV–63kV, arc suppression coils are increasingly of dry-type cast resin design due to the trend toward oil-free substations, especially for systems below 35kV.
8. Damping Reactor (often synonymous with Series Reactor)
Connected in series with capacitor banks or compact capacitors, damping reactors limit inrush current during capacitor switching—similar in function to current-limiting reactors. Filter Reactor: When connected in series with filter capacitors, they form resonant filter circuits, typically used for 3rd to 17th harmonic filtering or higher-order high-pass filtering. HVDC converter stations, phase-controlled static VAR compensators, large rectifiers, electrified railways, and high-power thyristor-based electronic circuits are all harmonic current sources that must be filtered to prevent harmonic injection into the grid. Power utilities have specific regulations regarding harmonic levels in power systems.
9. Smoothing Reactor (DC Link Reactor)
Ang smoothing reactors gigamit sa DC circuits human sa rectification. Tungod kay ang rectifier circuits nag-produce og finite number of pulses, ang output DC voltage adunay ripple, kini kasagaran harmful ug kinahanglan pag-suppress pinaagi sa smoothing reactor. Ang HVDC converter stations equipped sa smoothing reactors aron mapadami ang output DC mahitungod sa ideal posible. Ang smoothing reactors importanti usab sa thyristor-controlled DC drives. Sa rectifier circuits, especially medium-frequency power supplies, ilang pangunahon nga functions include:
Limiting short-circuit current (during inverter thyristor commutation, simultaneous conduction is equivalent to a direct short-circuit at the rectifier bridge output); without a reactor, this would cause a direct short;
Suppressing the influence of medium-frequency components on the utility power grid;
Filtering effect—rectified current contains AC components; high-frequency AC is impeded by the large inductance—ensuring continuous output current waveform. Discontinuous current (with zero-current intervals) would cause the inverter bridge to stop, resulting in an open-circuit condition at the rectifier bridge;
In parallel inverter circuits, reactive power is exchanged at the input; therefore, energy storage elements—reactors—are essential in the input circuit.
Important Notes
Ang reactors sa power grids gigamit aron absorb ang capacitive reactive power generated sa cable lines. Pinaagi sa adjustment sa number sa shunt reactors, ang system operating voltage mahimo mog regulate. Ultra-high voltage (UHV) shunt reactors serve multiple functions related to reactive power management in power systems, including:
Mitigating the capacitive effect on lightly loaded or no-load transmission lines, reducing power-frequency transient overvoltages;
Improving voltage distribution along long transmission lines;
Balancing reactive power locally under light load conditions, preventing unreasonable reactive power flow and reducing line power losses;
Reducing steady-state power-frequency voltage on high-voltage busbars when large generators are synchronized to the grid, facilitating generator synchronization;
Preventing self-excitation resonance that may occur when generators are connected to long transmission lines;
When the reactor neutral is grounded via a small reactor, the small reactor can compensate for inter-phase and phase-to-ground capacitance, accelerating the self-extinction of residual currents and enabling single-pole auto-reclosing.
Ang reactors giconnect either sa series o sa parallel. Ang series reactors kasagaran gigamit para sa current limiting, apan ang shunt reactors commonly gigamit para sa reactive power compensation.
Shunt Reactor: Sa ultra-high voltage long-distance transmission systems, giconnect sila sa tertiary winding sa transformers aron kompensahan ang capacitive charging current sa transmission lines, limita ang voltage rise ug switching overvoltages, ug ensure reliable system operation.
Series Reactor: Installed in capacitor circuits, they are used when the capacitor bank is energized.
