I = Current In Amps. V = Volts.

voltage ( V. ) current (I) slope = resistance (R)

The “I” is thought to have been meant to represent “Intensity” (of electron flow), and the other symbol for voltage, “E,” stands for “Electromotive force.” From what research I’ve been able to do, there seems to be some dispute over the meaning of “I.” The symbols “E” and “V” are interchangeable for the most part.

Current is the rate at which electrons flow past a point in a complete electrical circuit. At its most basic, current = flow. It expresses the quantity of electrons (sometimes called “electrical charge”) flowing past a point in a circuit over a given time.

Thus, electrons and holes conduct electric current in semiconductors. When voltage is applied, the electrons (negative charges) move from negative end of the battery to the positive end of the battery. A flow of negative charges in a circuit will produce the current same as the flow of positive charges produce.

The most economical power factor for a consumer is: 0.84 lagging. 0.9 lagging. 0.95 lagging.

A lower power factor causes a higher current flow for a given load. As the line current increases, the voltage drop in the conductor increases, resulting in a lower voltage at the equipment. With an improved power factor, the voltage drop in the conductor is reduced, improving the voltage at the equipment.

Benefits of Power Factor Correction

• Reduced Demand Charges.
• Increased Load Carrying Capabilities In Existing Circuits.
• Improved Voltage.
• Reduced Power System Losses.
• Reduced Carbon Footprint.

Power factor correction (PFC) aims to improve power factor, and therefore power quality. It reduces the load on the electrical distribution system, increases energy efficiency and reduces electricity costs. It also decreases the likelihood of instability and failure of equipment.

Synchronous Condenser Another way to improve the power factor is to use a 3 phase synchronous motor which is over excited and runs on no load. This setup is known as the synchronous condenser. The interesting part is that the synchronous motor can operate under leading, lagging or unity power factor.

Improving the PF can maximize current-carrying capacity, improve voltage to equipment, reduce power losses, and lower electric bills. The simplest way to improve power factor is to add PF correction capacitors to the electrical system. PF correction capacitors act as reactive current generators.

In electrical engineering, the power factor of an AC power system is defined as the ratio of the real power absorbed by the load to the apparent power flowing in the circuit, and is a dimensionless number in the closed interval of −1 to 1. Apparent power is the product of RMS current and voltage.

The power factor can get values in the range from 0 to 1. When all the power is reactive power with no real power (usually inductive load) – the power factor is 0. When all the power is real power with no reactive power (resistive load) – the power factor is 1.

A leading power factor signifies that the load current is capacitive in nature whereas a lagging power factor signifies that the load current is inductive. In this regard, a leading power factor can be corrected by adding inductive loads and a lagging power factor can be corrected by adding capacitive loads.

0.8 power factor is a measure of the delay or lead of current flow as compared to the application of the driving voltage. As A generator’s magnetic field is rotated around inside the stator the voltage it generates, when applied to a load, will force a current flow.

To find the PF, divide 100 kW by 125 kVA to yield a PF of 80%. This means that only 80% of the incoming current does useful work and 20% is wasted through heating up the conductors. Improving the PF can maximize current-carrying capacity, improve voltage to equipment, reduce power losses, and lower electric bills.

Hence, when a sinusoidal voltage is applied to an inductor, the voltage leads the current by one-fourth of a cycle, or by a 90º phase angle. Current lags behind voltage, since inductors oppose change in current. Changing current induces an emf. This is considered an effective resistance of the inductor to AC.

In a sinusoidal wave, the fist positive peak of the voltage cycle (90 deg) the current at the coil will be zero. When the voltage starts to decay, that’s the time when the current would starts to go up and reaches its peak at 180 deg when the voltage source E=0, That is why the current is lagging by 90 deg.

Another way to find it is to look at the angle of the current relative to the angle of the voltage. If the currents leads the voltage (greater angle than voltage) then the power factor is leading (capacitive load).