What happens when the power factor drops suddenly after a peak in electricity consumption?

The power factor is a further measure of the circuit on this basis, power factor = active power apparent power. Therefore, the maximum value of the power factor is 1. China also has strict regulations on power factor, transformers above 100kva, power factor shall not be lower; The power factor of agricultural users shall not be less than; The power factor of other electricity users shall not be less than.

If the actual power factor is lower than this value, you will face a fine from the power supply bureau (force rate electricity charge).

So, why does the power supply bureau charge extra (fine) for users with low power factor? This brings us to the consequences of a low power factor.

For the average user, a low power factor has no effect and no feeling. Because the improvement of the power factor needs to be carried out at the transformer end, the power supply bureau's force rate electricity fee is also for the transformer owner. The low power factor is extremely harmful to the power grid and users.

The low power factor indicates that there is more reactive power in the circuit. What causes high reactive power? Older transformers, old motors, or a large number of motors in a circuit can lead to an increase in reactive power.

The increase of reactive power is a major hidden danger for users and power grids.

The hazards of too high reactive power (low power factor) are as follows:

Electrical equipment needs to obtain useful power and useless power from the power supply end, if the power supply end of the useless power reserve is insufficient, it will inevitably cause the machine to be unable to produce enough magnetic field, and it will not be able to reach the rated power, can not operate normally.

This results in a reduction in the transmission capacity of the power grid.

The reactive power is uncontrollable, which will increase the wear and tear of equipment and lines.

The reactive power that the general power grid can provide is far from meeting the power demand of the power consumption unit, so the power consumption unit will generally use reactive power compensation equipment to meet its own demand for reactive power.

The power factor will definitely drop during peak electricity consumption. This is because the voltage drop in the line needs to be compensated. In this way, a state of equilibrium can be reached. So it's normal for the power factor to decrease.

The capacity of the transformer is required to be high, and the output capacity of the transformer is reduced.

If the power factor is too high, the reactive power is too low, and reducing the amount of no power of the system will affect the stability of the circuit. Although the economy is improved, in the long run, this is in exchange for increasing the probability of accidents, once a sudden accident occurs, the circuit may not be able to withstand a small disturbance or **, may lose step.

The power factor is equal to the power of the wheel-infiltrated work divided by the apparent power. The lower the power factor, the greater the reactive power. Unless there is a special need for the ridge, the larger the power should be, the closer it is to unit one, the larger the proportion of active power and the higher the power supply efficiency.

It will cause the increase of reactive power, the reduction of transformer output, the low efficiency of electricity consumption, the voltage drop, the frequency decrease, and the reliability of the power grid will be reduced or even collapsed.

The capacity of the transformer is required to be high, and the output capacity of the transformer is reduced.

The harm caused by the reduction of the power factor of the power supply system: 1. When the power factor of the user is low, it is necessary to absorb the reactive power from the network, so that the generator set will have more reactive power, and the reactive power also needs energy, and it sends less active power, which is equivalent to reducing the output of the generator; 2. The reactive load is transmitted on the network, which occupies the resources of transmission, transformation and distribution equipment in vain, so that the utilization rate of the above-mentioned equipment is reduced, and the operation efficiency of the equipment is calculated by active power, so it makes the equipment unable to reach the rated output, and the output is reduced; In order to achieve the specified output, it is necessary to increase the equipment capacity and increase the equipment investment; 3. Reactive power affects the voltage, the transmission of reactive power and a large amount of consumption, so that the system voltage can not meet the requirements, and the voltage at the end of the line will be very low, resulting in the equipment can not get up or the power factor is too low, which has a great impact on the power system, and especially has the greatest impact on the power grid enterprises: 1. When the power factor of the user is low, it is necessary to absorb the reactive power from the network, so that the generator set will have more reactive power, and the reactive power also needs energy, and it has less active power, which is equivalent to reducing the output of the generator; 2. The reactive load is transmitted on the network, which occupies the resources of transmission, transformation and distribution equipment in vain, so that the utilization rate of the above-mentioned equipment is reduced, and the operation efficiency of the equipment is calculated by active power, so it makes the equipment unable to reach the rated output, and the output is reduced; In order to achieve the specified output, it is necessary to increase the equipment capacity and increase the equipment investment; 3. Reactive power affects the voltage, the transmission and a large amount of reactive power consumption, so that the system voltage can not meet the requirements, and the voltage at the end of the line will be very low, resulting in the equipment can not start or can not reach the rated output; 4. The lack of reactive power will increase the current in the line and electrical equipment, increase the loss, that is, increase the line loss, and increase the electricity expenditure.

The electricity consumer is a load of 1 kilowatt, so no matter what the power factor is, or, in fact, the meter shows that it is 1 kilowatt-hour of electricity when he works for 1 hour, and the state stipulates that the electricity fee is charged according to the active electricity. It is precisely because of the above 4 reasons that the user's power factor is, or, the loss on the road is not the same, if the power factor of each user is low, it will not be together, so the user is required to "compensate on the spot" for the reactive power and compensate for himself; However, according to the regulations, users below 100kw are not equipped with reactive power meters, that is, do not assess reactive power, so users below 100kw rarely install reactive power compensation devices, in order to ensure system voltage, reduce line loss, and improve the utilization rate of equipment, power supply enterprises will invest a lot of money to transform equipment for centralized reactive power compensation; When the power factor of users above 100kw does not meet the standard (when large industrial users are), the cost and operating cost of power supply enterprises will be greater; Therefore, the state stipulates that the "power factor adjustment electricity fee" billing method is implemented for users who fail to meet the power factor standard to compensate for the excess cost expenditure of power supply enterprises. The power supply department is to measure the monthly average power factor, and there is a special "reactive energy meter" to record the reactive power consumption of a month, and it can calculate the power factor of the month by combining it with the "active energy meter" of this month.