Mutual inductance voltage of oil-immersed transformer
The terminal of th with the same name specifies that the terminal of the inductance current flowing into the coil and the positive polarity terminal of the mutual inductance voltage in the other coil are called the terminal of the same name of the two coupling coils, and they are marked with an asterisk or a small black dot. The reference polarity of the mutual inductance voltage is positive at the same end of the second coil if the current flows into the same end of one coil, or negative at the same end of the second coil if the current flows out of the same end of one coil.
Classification and requirements of oil-immersed transformer leads: the leads of electric oil-immersed transformer are round copper wire, copper bar and soft copper wire. Round copper wire is used when the lead diameter is less than 12mm. The cross section of the lead is 80 ~ 100㎜? When using copper bar. Soft copper wire is suitable for complex leads, widely used in large and medium-sized electric oil-immersed transformers.
The connection between the lead wire and the coil wire and between the lead wire, mostly brazing. Fine wires are also welded. The connection between aluminum coil and copper lead is argon arc welding. The connection between the lead and the sleeve, the lead and the tap switch, can be detachable with bolts, or the soft lead and the connection end can be fixed by pressing method.
Take a set of windings on the primary side and a set of windings on the secondary side. Either end of the two sets of windings is shorted together. LCR digital bridge is used to test the inductance value of the other end of the two sets of windings. If the inductance value is greater than the sum of the inductance value of the two sets of windings tested separately, the two ends of the test are the nameless end, and vice versa.
Post time: Oct-12-2021