Capacitors for Power Factor Correction, Saving Power & Money

Explain how current in a three-phase ac system generates magnetic fields and electric fields between phases. Clarify why capacitors lead, inductors lag, and resistors stay in phase, with XL, XC, and frequency.

Explain the meaning of the phase angle phi between voltage and current in capacitive and inductive loads, and how 50Hz and 60Hz translate this angle into time delay.

Learn how voltage, current, and phase angle define active, reactive, and apparent power, and how energy equals power times time in single- and three-phase systems, including power factor.

Explore the power triangle, linking active power P, reactive power Q, and apparent power S, and learn how the power factor cos phi governs efficiency and correction.

Explore how power factor links active power, reactive power, and apparent power. Capacitors in parallel supply reactive current, reduce source current, and improve the source power factor.

Illustrates how parallel capacitors with a 24 kW, 0.8 lagging motor raise the source power factor from 0.8 to 1 and reduce current from 45.6 A to 36.48 A.

Demonstrate power factor correction using a parallel capacitor with a 24 kW, 0.8 lagging induction motor, reducing source power from 30 kVA to 24 kVA and boosting PF to 1.

Demonstrate power factor correction by analyzing a leading synchronous motor with inductive and capacitive loads, showing how reactive power is reduced and transformer efficiency is improved.

Identify the main sources of reactive power to correct power factor, including synchronous motors, synchronous condensers, and static capacitors, and learn how reducing source reactive power improves efficiency.

Explain the meaning of reactive power and how capacitors supply reactive power to inductive loads, improving power factor while reactive energy is returned to the source.

Explain first method to calculate capacitor reactive power for power factor correction, using q capacitor = p source (tan phi old - tan phi new) to reduce source reactive power.

Calculate the capacitor reactive power to improve source power factor from 0.8 to 0.9 for 400 kW, using difference between tan phi old and tan phi new, yielding 106.4 kvar.

Use a different method to compute capacitor reactive power for correcting a source power factor from 0.8 to 0.9, illustrating the power triangle with S, P, and Q.

Learn the table method for calculating capacitor reactive power to improve power factor, using multiplying factors k from the tables and applying q capacitor = p source × k.

Calculate the capacitor reactive power Q capacitor using the table method to improve the power factor from 0.8 to 0.9 for a 400 kW motor, yielding 106.4 kilobars.

Use an excel sheet method to calculate capacitor reactive power for power factor correction; input active power and old and new power factors to get reactive power and factor k.

Compare three capacitor bank locations for power factor correction—global, sector, and individual—using reactive power calculations to raise pf from 0.7 to 1.0 and determine per-phase capacitance.

Capacitors improve power factor by supplying reactive power near loads, reducing reactive current and overall losses, while improving voltages and enabling new loads.

Explore how a medium voltage capacitor bank provides reactive power for power factor correction via regulator-controlled stages and series reactors, with components like surge arresters, isolating switches, and current transformers.

Explore the internal construction of capacitor units, from dual metal plates and dielectric to partial capacitors arranged in series and parallel, with safety features like discharge resistors and fuses.

Explore the construction of an 11 kV medium voltage capacitor unit, including partial capacitor units, brown paper saturated with oil insulation, aluminum foil plates, and the discharge resistor with fuse.

Explain why medium voltage capacitor banks fail, focusing on unbalanced capacitance and neutral current. Highlight preventive measures such as internal discharge resistors, interlocks, series reactors, surge arresters, and tests.

Compute reactive power and capacitor current to raise the power factor from 0.65 to 0.95 for a 400 V three-phase induction motor, and evaluate reductions in source kVA and current.

Power factor correction shows adding a parallel 150 kw synchronous motor to 800 kw induction motors at pf 0.8, raising to 0.93 and calculating active, reactive, and apparent powers.

Evaluate power factor correction using a delta-connected capacitor bank to raise pf to 0.95, calculate reactive power, current reductions, and kVA savings for four induction motors.

Explore a factory case study on power factor correction using a capacitor bank to raise PF from 0.785 to 0.95, assess energy savings, payback period, economics, and transformer current reductions.

The factory case study analyzes 12 induction motors at 6.6 kV with PF 0.785 and demonstrates a three-stage capacitor bank to improve PF to 0.95 and assess economic benefits.

Demonstrate capacitor bank based power factor correction, calculating year-long energy savings, 33.491 MWh, and a 7% economic return with a 0.25-year payback for a 66 kV factory network.

Concludes a factory case study on capacitor bank installation that improves power factor from 0.785 to 0.95, quantifying current reductions and a 3.58 MVA transformer power gain.