Commissioning of Power Transformers
Since I started the commissioning work 30 years back, transformer commissioning consisted of more tests, but nowadays, the number of tests has been reduced due to costs and time-saving. This article will go through complete testing that needs to be done at the site during the commissioning process of the transformer.
Power transformers testing and commissioning at the site
These tests include winding insulation resistance test, winding resistance test, vector group test, tan delta test, no-load test or iron losses, load test or copper losses, temperature rise test, partial discharge test, frequency response analysis test, and transformer oil breakdown test.
These tests are detailed as follows:
1.1 Measurement of Winding Insulation Resistance
The purpose of this test is to determine the insulation resistance of the high-voltage winding to the ground, low-voltage winding to the ground, and the high-voltage winding to the low voltage winding, also to assess the amount of moisture in transformer insulation.
1.2 Winding Resistance Test
The purpose of this test is to measure the D.C. resistance of the transformer windings, this test can be done by a voltmeter and ammeter method. For low reading values, we connect the voltmeter after the ammeter, but for high resistance values, we connect the voltmeter before the ammeter. A sensitive voltmeter and ammeter will be used with a 100 DC Amp
