Hello fellows, I hope you all are doing great. In today’s tutorial, we will have a look at Difference Between Leading and Lagging Power Factor. In AC power system the 2 most important parameters which are related to the power factor are lagging and leading power factors. the leading power factor current leads the voltage. While for lagging power factor current lags the applied voltage. The circuit that has to lead and lagging power factor depends on the load connected.
Before discussing lagging and leading power factors we must know about power factors. It is a very important parameter of an electrical power system. It is a dimensionless quantity It is explanations of energy. Its value lies in form of a percentage if the percentage is less P.F is less.Its is ratio of operating power to apparent power. Apparent power is called power demand for laod. It is multiple of volts and ampere its units is KVA
In the case of direct current circuitry, we can get the power of any circuitry through the multiple of voltmeter and ammeter reading. .It exits in both single and 3 phase circuits.But for ac circuitry products of these two parameters give only apparent power not the actual powerIt has no dimensions. Its value lies between plus minus and positive minusHence in ac circuitry, the net power given to circuitry which is apparent power is not only used through the circuitry. The power used by the circuit is called actual power in simple words power factor is the cosine of phase difference among voltage current. Its formula is power factor=Actual power/Apparent power. In today’s post, we will have a detailed look at the comparison among lagging and leading power factor and find their differences. So let’s get started with the Difference Between Leading and Lagging Power Factors.
Difference Between Leading and Lagging Power Factor
Leading Power Factor
- For this power factor current flowing through the load leads the voltage given to the load.
- Leading power factors is exits for the capacitive load connected with the circuitry.
- If the leading power factor is to be corrected of the system then the inductive load in the system.
- The value of the leading power factor lies between -1 to zero.
- Its reactive component is negative.
- The load that has leading power factors are capacitive load
motors, capacitor, radio circuitry.
Lagging Power Factor
- In lagging power factor load current lags the applied voltage.
- The inductive load connected with the circuitry has a lagging power factor.
- Examples of lagging power factors are inductive loads like an induction motor, generators, relays, etc.
- The correction of lagging power can be done with the use of capacitive load.
- Its value is between zero and one.
- Its reactive element is positive.
Lagging Power Factor Vs Leading Power Factor
- If the circuit has a such load that the load current lags the voltage then that load will have a lagging power factor and if the load current is leading the volts then that system will have a leading power factor
- Inductive loads like solenoids and induction motors have a lagging power factor and capacitive loads have a leading power factor
- -1 to 0 is the value of the lagging power factor and the leading power factor has 0 to 1
- For the leading power factor phase angle of the current is positive then voltage and for lagging, the power factor phase angle is negative w.r.t to the phase angle of volts
- Leading power factors have positive reactive elements and lagging power factors have negative
- In the case of leading power factors loads absorbed leading reactive power or provided the lagging reactive power and for the lagging power factor loads absorbed the lagging reactive power
- To improve the lagging power factor capacitive load connected to the circuit and for improvement of leading power factor inductive load like induction motor connected
- Examples of lagging factor loads are inductors, induction motors, and relay transformers, and leading power factor loads are synchronous motors, capacitors, etc
Difference Between Leading and Lagging Power Factor
| characteristic | Leading Power Factor | Lagging Power Factor |
|---|---|---|
| The phase angle between current and voltage | Current leads voltage | Current lags voltage |
| Reactive power | Supplied by the load | Consumed by the load |
| Reactive power component of apparent power | Negative | Positive |
| Power factor range | 0 to 1 | -1 to 0 |
| Example loads | Capacitors, overexcited synchronous motors, radio circuits | Induction motors, transformers, fluorescent lights |
| Benefits of improving power factor | Reduced energy costs, improved efficiency, increased capacity | Reduced voltage drop, improved equipment performance |
| Characteristic | Leading Power Factor | Lagging Power Factor |
|---|---|---|
| Phase angle between current and voltage | Current leads voltage | Current lags voltage |
| Reactive power | Supplied by the load | Consumed by the load |
| Reactive power component of apparent power | Negative | Positive |
| Power factor range | 0 to 1 | -1 to 0 |
| Example loads | Capacitors, overexcited synchronous motors, radio circuits | Induction motors, transformers, fluorescent lights |
| Benefits of improving power factor | Reduced energy costs, improved efficiency, increased capacity | Reduced voltage drop, improved equipment performance |
Example:
A load with a power factor of 0.9 leading to the load is providing 90% of the apparent power to useful work, and the remaining 10% is used to supply reactive power. A load with a power factor of 0.9 lags that the load is using 90% of the apparent power for useful work and 10% is being supplied by the utility.
Benefits of improving power factor:
- Reduced energy costs: Utilities charge higher rates for users with fewer power factors. By improving the power factor, customers can save money on their energy bills.
- Improved efficiency: With a higher power factor more of the incoming power is being used for useful work. This can cause improved efficiency for businesses and industries.
- Increased capacity: A higher power factor can help utilities to transmit power through their networks. It can be best for areas with high need for electricity.
Faqs
Difference between leading and lagging phase
- Leading phase: The current signal is ahead of the voltage waveform in time.
- Lagging phase: The current waveform lags the voltage waveform in time.
Is good power factor leading or lagging?
A leading power factor is considered to be better than a lagging power factor. Since leading power factor customers are essentially offering reactive power to the utility, which can help to increase the overall power system efficiency.
Is 0.8 power factor leading or lagging?
A power factor of 0.8 can be leading or lagging, based on the type of load. Like a capacitive load can have a leading power factor of 0.8, while an inductive load has a lagging power factor of 0.8.
What is 0.9 leading and lagging power factor?
A power factor of 0.9 leading shows that the load is supplying 90% of the apparent power to useful work, and the remaining 10% is used to supply reactive power. A power factor of 0.9 lagging is the load is using 90% of the apparent power for useful work, and the remaining 10% is provided by the utility.
Example of a leading and lagging power factor
- Leading power factor: A capacitor bank
- Lagging power factor: An induction motor
Leading and lagging with example
- Leading phase: A capacitor bank is a device that stores electrical energy in the form of an electric field. When a capacitor bank is attached to an AC circuit, it results in the current to lead the voltage.
- Lagging phase: An induction motor is an electric motor that uses a rotating magnetic field to produce torque. When an induction motor is working the current lags the voltage.
Can power factor be less than 1?
Yes, the power factor can be less than 1. In real mostly loads have a power factor that is less than 1.
Is power factor 0 leading or lagging?
A power factor of 0 is neither leading nor lagging. It is the current and voltage waveforms are accurately in phase.
What does 80% power factor mean?
An 80% power factor is that 80% of the apparent power is used for useful work, and the remaining 20% is being used to supply reactive power.
kVA to kW
To convert kVA to kW, we can use the following formula:
kW = kVA * power factor
For example, to convert 100 kVA at a power factor of 0.8 to kW, you would use the following formula:
kW = 100 kVA * 0.8 = 80 kW
Zero power factor
A zero power factor defines that the current and voltage are in phase. So that there is no real power being consumed, and all of the apparent power is used to supply reactive power.
Good power factor
A good power factor is one that is close to 1. Most of the apparent power is used for useful work, and less reactive power is being consumed.
kVAR
A kVAR is a unit of reactive power. Reactive power is the energy that goes back and forth between the load and the source but does not do any useful work.
Unit of power factor
The unit of power factor is dimensionless. it does not have a unit of measurement.
What happens if power factor is more than 1?
If the power factor is more than 1, it shows that the load is producing reactive power. It is not common, but it can happen in some conditions, like when a capacitor bank is used to increase the power factor.
Is power factor only for AC or DC?
Power factor is only for AC circuits. DC circuits do not have reactive power, so they do not have a power factor.
How do you calculate kVA?
To measure kVA, use the following formula:
kVA = voltage * current
Can power factor be negative?
Power factor can be negative, but it is not common. A negative power factor shows that the load is producing more reactive power than it is consuming.
What is 100% power factor?
A 100% power factor is that the load is using all of the apparent power for useful work. i the ideal power factor, but it is difficult to get in practice.
Why is zero power always 1?
Zero power always has a power factor of 1 since the power factor is defined as the ratio of real power to apparent power. When power is zero, both real power and apparent power are zero, so the power factor is 1.
Lowest value of power factor
The lowest value of the power factor is 0. Since the power factor can only be negative if the load is prodcucing reactive power.
