Hello Guys'
Here in this video effects of low power factor are shown.
According to power formula for 3 phase and 1 phase, the current is inversely proportional to power factor. Therefore if power factor will low, higher will be current and vice versa.

Disadvantages Of Low or Poor Power Factor
As we know
IL    œ    1 /  Cos Φ

It is clear by the above equations, the load current in single phase and three phases is inversely proportional to power factor in power system. I.e. low power factor in a power system leads to higher load current which is a major disadvantage of low power factor.
Disadvantages of Low Power factor:
Poor Power factor or power factor less than unity causes the following disadvantages
1) Effect on Transmission lines(Greater conductor size):
At low power factor, to transmit or distribute the power at a constant voltage requires more current. To transmit high current, higher conductor size transmission lines are needed. For example, In the case of single phase AC motor with load 20Kw on full load with terminal voltage 250V. At unity power factor full load current would be 20,000/250 = 50A. But at less power factor = 20000/250*0.8 = 100A. Now all the transmission lines and conductor and motor conductors should be rated to 100A instead of 80A. This increases the cost of transmission lines.

2) Effect on Generators, Transformers:
It is known that the electrical machinery (Generators, Transformers) etc are rated in KVA rather than kW.
Where;
KVA = KW/ power factor
i.e. The KVA is inversely proportional to KVA for a given KW. For lower power factor the electrical machinery should be having higher KVA rating to drive constant KW load. For example to drive a 20KW load with a unity power factor requires an electrical machine with 20KVA.If the power factor is lesser then the electrical machine higher than 20KVA is required to drive the load. Then the size and cost of the electrical machine becomes expensive.

3) high losses in power system
Due to the high current for low power factor, the copper losses increases in the transmission conductors and switch gear machinery.

4) High Voltage drops (poor voltage regulation):
The large current at low lagging power factor causes greater voltage drops in alternators, transformers and transmission lines. This results in decrease in voltage at the driving end and enables the use of extra equipment to counter act the voltage drop like voltage stabilizers. This increase the cost of power supply system.
The low power factor reduces the handling capacity of the system. I.e. the reactive competent in the current prevents the full use of machinery in power system.

You can also watch the previous videos by clicking on the link provided below: -

1.DOL STARTER: - [ Ссылка ]
2.DOL STARTER (USING MPCB) : - [ Ссылка ]
3.DOL Starter Forward Reverse Operation: - [ Ссылка ]
4.Forward And Reverse Operation of 3 Phase Induction Motor With Interlocking:- [ Ссылка ]
5.Controlling of 3 Phase Induction Motor from 3 Different Locations: - [ Ссылка ]
6.Contactor: - [ Ссылка ]
7.Testing & Practically Use of Contactor: - [ Ссылка ]
8.Flourscent Tube Light: - [ Ссылка ]
9.Series Test Board: - [ Ссылка ]
10.Godown Wiring: - [ Ссылка ]
11.Hostel Wiring: - [ Ссылка ]
12.Power Factor: - [ Ссылка ]
13.Power Factor For Various Loads: - [ Ссылка ]

So guys, I think this video clear the concept of power factor. If there is any doubt please comment in comment box.
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