Transformer Voltage Regulation
In electrical engineering, particularly power engineering, voltage regulation is a measure of change in the voltage magnitude between the sending and receiving end of a component, such as a transmission or distribution line.
The output voltage of a transformer is changed depends on load resistances and a constant voltage input. The degree of variance is affected by the primary and secondary winding inductances, among other factors, not the least of which includes winding resistance and the degree of mutual inductance between the primary and secondary windings. For power transformer applications, where the transformer is seen by the load as a constant source of voltage, it is good to have the secondary voltage vary as little as possible for wide variances in load current.
The measure of how well a power transformer maintains constant secondary voltage over a range of load currents is called the transformer’s voltage regulation. It can be calculated from the formula as shown in the above picture. Here full-load means the point at which the transformer is operating at maximum permissible secondary current. This operating point will be determined primarily by the winding wire size and the method of transformer cooling.