What is excitation voltage and what is excitation power

It provides a working magnetic field for generators and other "electrical equipment that works by the principle of electromagnetic induction", which is called excitation (or excitation); The voltage required to provide the working magnetic field is called the excitation voltage or excitation voltage, and the current generated is called the excitation current.

The excitation voltage is generally DC voltage.

The voltage required for the motor rotor.

The excitation current, also known as the excitation inrush current, is obviously affected by the excitation voltage. That is, as long as the system voltage changes, the excitation voltage is affected, and the excitation inrush current will be generated. Under different circumstances, different degrees of excitation inrush current, such as initial, voltage recovery, and resonance (sympathy), will be generated.

The instantaneous spike and duration will depend on a combination of factors and may be as high as 8 to 30 times the rated current of the transformer.

The excitation inrush current is not dangerous to the transformer because this inrush current exists for a short period of time. Of course, it is also not good for the transformer to be continuously closed and charged many times, because the multiple impacts of the large current will cause the mechanical force between the windings, which may gradually loosen the fixed objects. In addition, the excitation inrush current may cause the differential protection action of the transformer, so it should be taken care when operating the transformer.

Effect of excitation inrush current on transformer differential protection. The differential is to calculate the differential current with the current of the primary and secondary sides of the transformer, when the transformer is in normal operation, the excitation current is very small, when there is an excitation inrush current, the influence of the excitation current should not be ignored, the usual practice is to rely on a variety of discrimination conditions to judge the excitation inrush current, reliable locking differential protection, wherein the discrimination method is to use the above characteristics to identify the inrush current. For example, the use of second harmonic braking, waveform symmetry principle, the use of fast saturation core of the differential relay.

The excitation inrush current is due to the magnetic saturation of the iron core, and the excitation inrush current usually begins to be generated after the power supply is turned on 1 4 cycles, and the maximum amplitude may exceed several times or even dozens of times the rated current of the transformer, and the duration is long, ranging from dozens of power cycles to tens of seconds. The amplitude of the excitation inrush current is not related to the secondary load of the transformer, but the duration is related to the secondary load, the larger the secondary load, the shorter the inrush current lasts, and the smaller the secondary load, the longer the inrush current lasts, so the no-load transformer inrush lasts the longest. The larger the capacity of the transformer, the greater the amplitude of the inrush current and the longer it lasts.

When the transformer is put into the transformer at the moment of voltage crossing zero, the most severe magnetic saturation phenomenon occurs, so the excitation inrush current is maximized. When a transformer is put into the transformer at a peak voltage, there is no magnetic saturation and therefore no inrush current.

Due to the large amplitude of the inrush current, the combined effect of the inrush current and the line inductance can lead to disturbances in the grid voltage and even serious overvoltages. The use of synchronous input technology to enable power grid equipment to be connected to the power grid at the appropriate phase point can effectively reduce inrush current and overvoltage, and minimize the interference to the power grid.

The explanation of the word excitation is: excitation jīcí. (1) The current passes through the coil and excites to generate a magnetic field. (2) It is also called "excitation".

The explanation of the word excitation is: excitation jīcí. (1) The current passes through the coil and excites to generate a magnetic field.

(2) It is also called "excitation". The phonetic pronunciation is: 一 .

The structure is: excitation (left and right structure) magnetic (left and right structure). The pinyin is:

jī cí。

What is the specific explanation of excitation, we will introduce it to you through the following aspects:

1. Online explanation [click here to view the details of the plan].

Excitation is a Chinese word that is interpreted as the current passing through a coil and excitation to produce a magnetic field.

Idioms about excitation.

Emotional, impassioned, grateful, and agitated, the water is excessive.

Spring-calling words about excitation.

Excessively excited, generous, wind-back, electric, grateful, water-excited, drought-grateful, grateful, impassioned, star-current, electric, lips, such as a passionate Dan, emotional.

Sentence formation about excitation.

1. Before the invention of the exciter, the generator installed on the tractor had to be connected with two dry battery packs to generate electricity normally, and the tractor drivers who went to work in the field had to carry two batteries with them.

2. Then, taking the double excitation structure as the class, the detailed process of the finite element analysis of the magnetic field of the magnetic strip denier system of the tube stranding machine is given, and the results are made.

3. It is believed that the harmonic source comes from the system side, and in addition to the nonlinear load, it is mainly caused by the excitation current of the large power transformer.

4. The second is the voltage obtained by the induced electromotive force generated by the stator winding under the action of the excitation magnetic field, which is characterized by a long voltage duration and greater harm.

5. Usually small generators use torsional armatures, while large generators use fixed armatures and twisted excitation wire sets.

Excitation is a device that provides power to the rotor of the generator. According to the different excitation methods of the DC motor, it can be divided into other excitation, and excitation, series excitation, compound excitation, etc., in the rotation process of the DC motor, the excitation is to control the voltage of the stator to make the magnetic field change, change the speed of the DC motor, and change the excitation also plays a role in changing the speed.

The main functions of excitation are:

1. Maintain the generator terminal voltage at a given value, and when the generator load changes, the generator terminal voltage is constant by adjusting the strength of the magnetic field.

2. Reasonable distribution of reactive power between parallel operating units.

3. Improve the stability of the power system, including static and transient stability and dynamic stability.

Types of excitation: According to the rectification method, it can be divided into two categories: rotary excitation and static excitation.

Rotary excitation also includes DC AC and brushless excitation; Stationary excitation includes a static exciter with an electric potential source and a static exciter with a composite power supply.

Power transformers are put into the grid at no load or external faults are removed.

When the voltage is restored, due to the saturation of the magnetic flux of the transformer core and the nonlinear characteristics of the core material, a considerable excitation current will be generated, which is called the excitation inrush current.

The value of the excitation inrush current is very large, and sometimes the rated current can be reached.

3 8 times, may cause the transformer differential protection to act mistaken for fault current. At the same time, the excitation inrush current can cause winding deformation, which reduces the service life of the transformer. The multiple harmonic components and DC components contained in the excitation inrush current will reduce the power supply quality of the power system, and the higher harmonics in the inrush current will have a strong destructive effect on the sensitive power electronic devices connected to the power system.

Excitation current, synchronous (generator) motor, is to give a current to the excitation winding to let it generate magnetic flux, and then (generator stator cutting and rotating magnetic flux to produce current) motor and stator current to generate magnetic flux interaction and rotation. The magnetic material with the same magnitude affects the output (voltage) power and the cross-section of the current conductor that affects the magnetic flux.