Information about Automatic Voltage Regulator (AVR)
by Starlight Generator dieselgeneratortechAfter the generator set starts,
it relies on the residual magnetic voltage of the motor. After rectifying, it
provides the excitation current to the magnetic field of the AC excitation
machine, and the armature voltage of the AC excitation motor increases
gradually. The AC voltage is fed into the host magnetic field after the
rotation rectifier, which makes the main generator establish the voltage. When
the speed is close to the rated value, the voltage regulator AVR makes the
generator rise rapidly and stabilize at the rated value. The electrical
principle is shown in the diagram.
During normal operation of
generator, if for some reason, such as load change, speed change, winding
temperature change and so on, the generator terminal voltage will increase or
decrease. Automatic voltage regulator AVR can detect this small voltage
deviation and rapidly reduce or increase the excitation current to maintain the
generator terminal voltage approximately unchanged.
Automatic Voltage Regulator, AVR
The AVR and D202 types of
automatic voltage regulators, all of which are printed on the road board, can
be installed in the junction box or removed from the machine and installed on
the control screen through a multi-core connector or bolt. Special attention
should be paid to regulating the ventilation and cooling of AVR when moving out
of the machine.
Voltage Regulator Data And
Excitation System Wiring Diagram
The connection of D202 in the
excitation system is shown in the figure below, and the relevant data are as
follows
1, magnetic field winding of
exciter
2, rotor winding of exciter
3, rotating rectifier
4, magnetic field winding of
generator
5, main stator winding of
generator
6, auxiliary winding
7, differential transformer
8, differential potentiometer
9, remote voltage regulating
potentiometer
10, third harmonic winding
AVR
RP1: voltage regulation
RP2: stable regulation
R1: integral time constant
regulation
RP3: 50Hz frequency inflection
point adjustment (K2 open)
RP4:Voltage regulation at 50Hz or
60Hz
RP5: The frequency inflection
point adjustment of 60 Hz (K2 on) 3.6.1 can be used in 50 Hz and 60 Hz
generators, and when used in 60 Hz generator, the K2 switch is placed in
"on" position (that is, disconnecting position).
Measuring transformer input
voltage of 400 volts (or 230 volts)
Quick fuse 10 A for short circuit
and overload protection, 5 seconds (this receptacle is mounted on the regulator
board).
When load buffering and U / F =
constant functions are required, the K3 switch is placed in the "on"
position, and the K3 switch is placed in the "off" position when
these two functions are not required.
When remote voltage regulation is
required, the short circuit connection between RV1 and RV2 can be disconnected
to a K Ω potentiometer (recommended multiple cycles potentiometer).
The N1W1 is connected short when
it leaves the factory, if it is required to run in parallel, the short
connection is folded, and the differential adjustment device is connected at
this two terminals (this device is composed of a current transformer and a
potentiometer and connected together). The side capacity of the current
transformer is 1VA, the current is 1A, and the potentiometer is 20WN 5 Ω. Note
that the current transformer of the adjusting device cannot be connected in the
same phase with the voltage measuring transformer of the AVR, for example, the
voltage measuring transformer of the AVR is connected to the V-W phase, then
the current mutual sensor for the adjustment of the difference shall be
connected in the U phase.
Adjustment
Voltage Adjustment
Adjust the voltage value, can
adjust the potentiometer RP1, can adjust the generator terminal voltage within
±5 UN range, if connected with the remote control voltage setting
potentiometer, it should be adjusted to the middle position, then adjust the
RP1 to make the terminal voltage rating. At this point, the remote control
potentiometer can adjust the generator terminal voltage in the range of ±5%
rated voltage.
Stabilization Adjustment
When the generator is unloaded,
the RP2is rotated slowly counterclockwise until there is a slight wobble in the
voltmeter pointer, and then rotate clockwise to make the terminal voltage
stable. This should be the best stability point. The integral capacitance can
also be adjusted to increase stability. When the open K1 is pulled to
"on", the integral is increased, and the best stable state can be
obtained by adjusting RP2. Switch K 1 has four gears and the fourth gear is
empty. When leaving the factory, the K 1 switch is generally unplugged in the
first gear.
Sponsor Ads
Created on Oct 21st 2018 23:03. Viewed 352 times.