What is generator grid connection Why should generators be connected to the grid

Only when the generator is connected to the grid can it generate electricity and transmit the electric energy for our thousands of households. On the contrary, without grid connection (also called derailment), the generator cannot generate electricity, let alone transmit electricity.

Whether it is connected to the grid or detrained, it is done through the exit switch of a generator.

The grid connection of the generator is to connect the generator with the power grid (it can also be considered that the power grid is a lot of users who need electricity) through the closing of the generator outlet switch, so that the electric energy can be continuously transmitted. There are three conditions for generators to be connected to the grid: the frequency, voltage, and phase of the generator must be consistent with the frequency, voltage, and phase of the power grid in order to be connected to the grid for power generation.

The three conditions are exactly the same, which is called the same period; There is a slight deviation, but it is called the same period within the allowable range).

I don't want to generate electricity, but I still disconnect the generator from the grid through the opening of this outlet switch, which is called delisting; When I want to generate electricity, I close it at the same time, which is called grid connection.

1. Conditions for generator grid connection:

1) The frequency of the generator is the same as the frequency of the system.

2) The outlet voltage of the generator is the same as the system voltage, and its maximum error should be within 5%.

3) The phase sequence of the generator is the same as that of the system.

4) The voltage phase of the generator is consistent with the phase of the system voltage.

When the above four conditions are met, the grid-connected switch can be closed to make the generator set merge into the system for operation.

2. Steps for generator grid connection:

1) Turn on the power supply of the excitation adjustment cabinet, confirm that the operation-exit switch is in the exit state at this time, and set the input (exit is at the exit.

state, pass in the exit state).

2) Put the excitation into the trolley, put the excitation into the low-voltage side switch, and close the demagnetization switch.

3) Put the local (main control to the spot), manual (automatic to automatic), run (exit to run), set input (exit to input), stator voltage will appreciate the default value, slowly increase the excitation voltage, until the stator voltage reaches the rated voltage of the generator, exit the set.

In this process, it is necessary to observe whether there is any abnormal change in the sampling of each group of generators, if there is, stop the voltage boost, find out the cause, and if necessary, directly jump the demagnetization switch.

The main operation of the synchronous screen (manual synchronous and automatic synchronous can be selected, before that, the generator incoming trolley is called to the working position, and the 122 switch is pushed to the working position).

1) Hit the place from afar.

2) Manual automatic to manual.

3) The locking switch is put into operation at the same time.

4) Select 1TK of Line 1

5), the handle to thick, observe the grid on both sides of the voltage abnormal, if not, and then the handle to fine, then the manual meter in the middle of the pointer will rotate clockwise, if not, you can adjust the generator frequency, near 12 o'clock direction (+-20 degrees), according to the manual closing automatic quasi-synchronous.

The remote local to the spot, manual automatic to automatic, the device is powered on at the same time, the locking switch is put into the same period, the synchronous switch is put into the selected channel, and the start synchronous button is pressed.

1) Check whether the current and voltage circuits of each group of generators are correct.

2) Put all the handles on the screen at the same time to the exit state, put the input on the excitation adjustment cabinet (exit in the exit state), restore the steam engine jump and demagnetization jump plate, and check whether the current, voltage and power of each group of generators are normal.

1) The frequency of the generator is the same as the frequency of the system.

2) The outlet voltage of the generator is the same as the system voltage, and its maximum error should be within 5%.

3. The residual field sequence of the generator phase is the same as the phase sequence of the system.

4) The voltage phase of the generator is consistent with the phase of the system voltage.

Generators have a wide range of uses in industrial and agricultural production, national defense, science and technology, and daily life. There are many forms of generators, but their working principles are all based on the laws of electromagnetic induction and electromagnetic forces. Therefore, the general principles of its construction are:

Magnetic circuits and circuits that use appropriate magnetic and conductive materials to generate electromagnetic power and achieve the purpose of energy conversion.

Electricity generation refers to "electricity"; It is the power and electricity that should be transmitted and sold to users through the power system. Connecting to the grid means that the power generation device transmits electricity to the power grid, and the electricity is transmitted out.

Power generation refers to "equipment"; It is a physical connection between generators and bulky power generation equipment and the power system. "Grid connection of power generation" is the premise and guarantee of "power generation grid". The grid-connected point is equipped with an anti-reverse slip-flow device, that is, the electricity generated is used for its own use, and the anti-backflow device is used to cut off part of the power generation, and the power grid is less to supplement a part of it.

The generator voltage is the same as the voltage of the electric fiber network, the voltage RMS value is the same, the phase is the same, the phase sequence is the same, and the frequency is the same.

The motor grid connection should meet the requirements of threeconditions: The voltage of the generator to be merged is equal to the voltage of the system; The cycle rate of the generator to be merged is equal to the rate of the system; The phase angle of the generator to be merged coincides with the phase angle of the system.

When the four conditions are met to destroy the key, the grid-connected switch can be closed to make the generator set merge into the system for operation.

ThreeStep 1Exactly the same is called the same period; There is a slight deviation between the light and the close, but within the allowable range, it is called the same period, and the opposite of the grid connection is the decolumn, the decolumn is not to generate electricity, or through the opening of this outlet switch, the generator is disconnected from the power grid, which is called decolumn; When you want to generate electricity, you can close it at the same time, which is called grid connection.

When the synchronous generator is connected to the grid, in order to reduce the instantaneous impulse current generated in the circuit composed of the power grid and the generator set, it is necessary to ensure that the voltage of the synchronous power generation beam cavity machine is equal to the instantaneous grid voltage when it is connected to the grid, so as to obtain the ideal conditions for the grid-connected operation of the synchronous generator

1) Both parties should have the same phase order;

2) Both sides should have equal effective values of voltage;

3) Both sides should have the same or very close frequency and phase.

Among the above three conditions, the phase order must be met, while the other two conditions must be met as much as possible.