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Overview
This product is a lightweight test device based on the principle of utilizing the saturation characteristics of the magnetization curve of silicon steel sheets in the power frequency grid, inducing zero-sequence third harmonic electromotive force in the secondary coil of a transformer connected in an open delta configuration.
It can be provided as a complete set including control equipment and chassis. This generator is one of the basic equipment for performing frequency-doubled induction high voltage tests on small-capacity power transformers and cascade high-voltage potential transformers in power systems, power plants, substations, and power supply and distribution networks. It can also be used for frequency-doubled and voltage-doubled tests on various low-voltage electronic and instrument power transformers, inductor coils, and electrical coils. Additionally, it can serve as a frequency-doubled power source with a power not exceeding 1 kilowatt for power supply or testing of certain special electrical equipment.
This product is a static frequency conversion device with low noise and small size, and it can completely replace traditional frequency conversion units in high-voltage systems.
Working Principle:
For the model and specifications of the triple frequency complete withstand voltage test device, the primary sides of three single-phase transformers are connected in a star configuration, and the secondary sides are connected in an open delta. When a symmetrical three-phase sinusoidal power supply is applied to the primary side, and the voltage is increased to saturate the iron core magnetic circuit, the third harmonic component in the magnetic flux increases, correspondingly increasing the third harmonic voltage induced in the iron core coil.
For the model and specifications of the triple frequency complete withstand voltage test device, the 150 Hz (three times the power frequency) induced voltage output from the secondary side of the open delta generator serves as the triple frequency test power supply voltage.
When the triple frequency generator is loaded with a load such as a JCC-220 high-voltage cascade potential transformer, its current changes from inductive to capacitive. Due to the low power factor, the efficiency of the generator is relatively low, generally only about 20%. Therefore, a reactor can be connected to a certain idle winding of the test object for current compensation to improve the power factor of the entire test circuit.
Technical Parameters
Technical Parameter Table
|
Output
Capacity
(KVA)
|
Transformer Primary
Rated Data
|
Transformer Secondary
Rated Values
|
Third
Harmonic
Ratio
|
Compensation
Reactor
|
Load
Test
Time
(Seconds)
|
Dimensions
Length×Width×Height
(mm)
|
Weight
(kg)
|
Voltage
(V)
|
Current
(A)
|
Frequency
Hz
|
Connection
|
Voltage
(V)
|
Current
(A)
|
Frequency
Hz
|
Connection
|
Inductance
(mH)
|
Maximum
Current
(A)
|
10
|
380±
10%
|
20A
|
50
|
Y
|
500±
10%
|
30
|
150
|
△
|
0.5
|
3~20
|
59~
60
|
60
|
Control box 500x440×700
|
45
|
Operating Instructions:
5.1 Connect the working circuit according to the schematic. Ensure that the generator housing, control box housing, and common ground wire are properly grounded. Do not arbitrarily connect to water pipes, as this may endanger personal safety and equipment.
5.2 Set the overcurrent relay and timing alarm according to the current level and withstand voltage time required for the normal induction withstand voltage test of the test object.
5.3 After preparation and verifying the circuit is correct, close the main power switch of the generator. The power indicator light will illuminate.
5.4 Press the start button; the green button indicator light will illuminate. Then, slowly and uniformly rotate the voltage regulator handle clockwise, gradually increasing the voltage while closely monitoring the voltmeter indication and the condition of the test object until the required test voltage is reached.
5.5 To test the withstand voltage time of the product, set the timer to the desired duration. The product will be tested under voltage for the specified time, then the main circuit will automatically disconnect. At this point, return the voltage regulator handle to zero, press the stop button, and cut off the main power switch.
Note: The above information and technical parameters are compiled and released by Yangzhou Darui Electric Co., Ltd.
