Can the power factor of the line be increased to 1?

Analysis: First of all, we want to explain that usually we write "power factor", which is a number, a coefficient, a coefficient not greater than 1. That is, the work that could have been done, but the actual work could not be done so much, and some useless work was done, so it was multiplied by a coefficient.

In AC circuits, the cosine of the phase difference ( ) between voltage and current is called the power factor, which is represented by the symbol cos, and numerically, the power factor is the ratio of the active power to the apparent power, i.e., cos = p s

The power factor of the power factor is related to the load nature of the circuit, such as the power factor of the resistance load of incandescent bulb and resistance furnace is 1, and the power factor of the circuit with inductive or capacitive load is generally less than 1. Power factor is an important technical data of the power system. The power factor is a factor that measures the efficiency of electrical equipment.

The low power factor indicates that the reactive power of the circuit for alternating magnetic field conversion is large, which reduces the utilization rate of the equipment and increases the power supply loss of the line. Therefore, the power supply department has certain standard requirements for the power factor of the power consumption unit.

Hehe. After 25 years of production of GZ K reactive power compensation controller (concompensators: JKG, JKW, JKL and other compensators), when we provide products and services to users, there are often users who ask this question, and the answer is:

Of course you can, that is, to reach the maximum value of the power factor.

However, it is very difficult to achieve such a situation, and at present, it is generally only possible to achieve true dynamic compensation.

If it is a general load line, it can be approached by dynamic + static compensation, and the time will not be too long and unstable. 1. The whole line is in a pure resistive state.

There are two common ways to improve the power factor of a circuit:

1. Improve the natural power factor.

The natural power factor is the power factor of a consumer without any compensation. The natural power factor can be improved by reasonably selecting asynchronous motors, avoiding transformer no-load operation, reasonably arranging and adjusting the technological process, and using synchronous motors instead of asynchronous motors.

2. Artificial compensation of reactive power is adopted.

Compensating for reactive power can improve the power factor, and devices such as power capacitors can be used to manually compensate for reactive power.

Do you want to calculate the power factor of the substation outgoing? Do you want to calculate the monthly average power factor, the monthly cumulative power factor, or the instantaneous power factor?

The power factor is actually an instantaneous value, because the load changes all the time, and the power factor changes. If the power factor is calculated solely based on the amount of electricity, there are positive and negative reactive power, which will be canceled. For example, if the power factor of 24 hours is calculated, if there are 4 hours of reactive power reversal within 24 hours, and the power factor is negative, then according to the calculation of electricity, the negative reactive power of these 4 hours will be offset with the positive reactive power of 20 hours, and the power factor obtained is better.

It is recommended to use the average power factor calculation method, which is to calculate the average power factor for each hour.

In addition, you say that there is active and reactive power at both ends of the line? Could it be that your line is ring power or hand-in-hand power supply, and can supply power at both ends together? If this is the case, the active power = (the feed at the head end - the reception at the end of the end) + (the feed at the end - the reception at the head), and the same is true for the reactive power.

Line power factor = line active power Line apparent power.

The active power of the line is generally known by the active power meter of the line according to the indication of the meter, and the apparent power of the line = the voltage of the line or bus The current of the line

In a three-phase circuit, p = 3uicos, p is the active power, u is the line voltage, i is the line current, and cos is the power factor.

In a single-phase circuit, p=uicos, p is the active power, u is the voltage, i is the current, and cos is the power factor.

At the same power, the higher the power factor, the smaller the current. The resistance of the transmission line is relatively fixed, and the line loss is proportional to the square of the current, so the higher the power factor, the smaller the current, and the smaller the line loss.

Because the transmission capacity s = (p q), when the active power p remains unchanged, increasing the power factor means decreasing the reactive power q, which reduces the transmission capacity s. The transmission current i = s 3 u, so the current i decreases. The active loss on the line is equal to i r because the decrease in the current i greatly reduces the loss.