Three-phase transformer how to calculate the current, ah, the formula is?
For example: 10KV / 0.4KV, 500KVA transformer
Primary current: I1 = 500 / (1.732 * 10) = 28.9A
Secondary current: I2 = 500 / (1.732 * 0.4 = 721.7A
Very simple S = 1.732 * U * I, get: I = S / (1.732 * U) such as transformer capacity S = 1000KVA, high side 10.5KV I = 54.99 A low side 400V I = 1443A
Calculation formula and empirical formula of transformer secondary current
Three-phase transformer current calculation formula I = S / (root number 3 * U), where U is the transformer line voltage, KV
Transformer Current Experience Port Algorithm: Primary Current I ≈ S * 0.06 Secondary Current I ≈ S * 1.5
For example: a 500KVA transformer to calculate the current and secondary current, with the current formula I = S / (root 3 * U) I = 500 / root 3 * 10 = 500 / 17.32 ≈ 28.8AI = 500 / root 3 * 0.4 = 500 / 0.69 = 724.6A with the transformer current experience calculation formula: I = 500 * 0.06 ≈ 30A I = 500 * 1.5 = 750A
Transformer operating load requirements
For example: a 800KVA10 / 0.4KV transformer, according to the first and second current calculation, a variety of load current is how much?
Solution: Primary current I = S * 0.06 = 800 * 0.06 = 48A Secondary current I = S * 1.5 = 800 * 1.5 = 1200A Low load: Primary current I = 48 * 15% = 7.2A
Secondary current I = 1200 * 15% = 180A
Reasonable load: primary current I = 48 * 50% = 24A
Secondary current I = 1200 * 50% = 600A
Full load: primary current I = 48 * 75% = 12A
Secondary current I = 1200 * 75% = 900A
