Single-phase power calculation method
1. The formula for calculating single-phase active power.
The formula for calculating the single-phase active power is: p=uicos
Where: p - power (w).
U – Voltage (V).
i – current (a).
cos – power factor.
2. Measurement method of single-phase active power.
1.Voltmeter and ammeter measure active power method.
The voltage and current are measured, and then the active power is calculated by p=ui. This method is simple and easy, but the accuracy is not high, and it is suitable for occasions where accuracy is not required.
2.Watt table method.
The watt meter method is a method of calculating the active power by measuring the power factor and the power value, and then using the power factor. This method is highly accurate, but it requires the use of watt meters, and the operation is relatively complex.
3.Power factor table method.
The power factor meter method is a method of measuring the power factor, voltage, and current values, and then calculating the active power by p=uicos. This method is highly accurate and easy to operate, but requires the use of a power factor table.
3. Calculation example of single-phase active power.
Suppose the rated voltage of a single-phase load is 220V, the rated current is 10A, and the power factor is 08, then the active power of the load can be calculated by the following formula:
p=uicosφ=220×10×0.8=1760w
Therefore, the active power of this single-phase load is 1760W.