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Eatonin tasasuuntaajia ja taajuusmuuttajia (rectifiers and inverters)
Induktiomoottorin käynnistäminen sarjainduktansin avulla
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From which the step resistors can be calculated, when k gets the values 0, 1, 2, and so on. This equation follows from the fact that the slip voltage is constant during the change of the start-up step, but the current changes at that time from the minimum value to the maximum.