What is the relationship between phase voltage, phase current, line voltage, and line current?
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What is the relationship between phase voltage, phase current, line voltage, and line current?
This question. . . . . It’s better to read books; that way you’ll remember it well. :lol
As the name implies, the phase voltage is the voltage between the live wire and the neutral wire. Phase current: It is the current in the load between the live wire and the neutral wire. Line voltage: The voltage between live wires. Line current: The current in the live wire.
Star connection: Line voltage = √3 × Phase voltage; Phase current = Line current. Delta connection: Line voltage = Phase voltage; Line current = √3 × Phase current
It’s a relationship involving square root 3; it’s better to consult some professional literature for details!
Look up \"Fundamentals of Electrical Engineering\"; it covers the basic knowledge.
When powered by a three-phase supply, there are three phase wires, which are what people commonly refer to as live wires, and one neutral wire, which is what people commonly call the zero wire; industry professionals refer to it as the working neutral wire. The phase difference between the currents in the three phase wires is 120 degrees. The voltage between these three phase wires is known as line voltage; for circuits with a voltage level of 400V, the voltage at the end of the circuit is around 380V. The voltage between any one of the phase wires and the neutral wire is called phase voltage, which is 230V, while the voltage at the end of the circuit is 220V. The relationship between phase voltage and line voltage is 1.732; 220V * 1.732 equals approximately 380V.
\"Line\" refers to the distance between two live wires, while \"phase\" refers to the distance between a live wire and the neutral wire. The same principle applies to voltage and current; this is knowledge from high school level. The key thing is that these terms are easily confused with each other, so just remember that a \"line\" represents a larger distance – specifically, 1.732 times larger
Star connection: Line voltage = √3 × phase voltage; Phase current = Line current； In delta connection, the line voltage equals the phase voltage, and the line current equals √3 times the phase current. In summary, it’s a root-3 relationship.
For a three-phase symmetric load connected in star configuration: (1) the line voltage is √3 times the phase voltage, and the line voltage leads the phase voltage by 30°. (2) The phase current is equal to the line current. When a three-phase load is connected in a triangular configuration: (1) the line voltage is equal to the phase voltage. (2) The line current is √3 times the phase current, with a phase lag of 30 degrees relative to the phase current