Transformer Serves
Rhys. 1. Arrangements and vector diagram of the voltage transformer: a - diagram, b is the vector diagram of voltage, into a vector diagram of voltage
In the operation of the voltage transform without error, its primary and secondary voltages coincide with the phase as shown in Figure. 1, 6, and their ratio is Kn. In the transformation factor Kn=1 voltage U2=U1 (Figure 1, V).
Measuring voltage transformers with two secondary rims
Pressure transducers with two secondary circuits, other than measuring devices and relays, are intended to operate on land-locking signalling devices on an isolated neutral network or to protect against land-locking on a ground-neutral network.
Transformator Scheme The voltage with two secondary rims is shown in Figure. 2, a. The conclusions of the second (additional) moor used to indicate or protect when land-locking are marked by hell and hd.
In rice. 2. 6 a diagram of three such voltage transducers in the 3-phase network. Primary and main secondary moorings are connected to the star. The primary wash is grounded. Three phases and zeros may be applied to measuring instruments and relays from the main secondary moles. Additional secondary refrigerants are connected by the diagram of the detached triangle. All three phases of phases shall be supplied to alarm or protective devices.
In the normal operation of the voltage transducer network, this vector is zero. It's from the vector diagram of the rice. 2, where Ua, Vv and Uc are vectors of phase voltages attached to primary rims, a Ubd, Ubd and Ucd are primary voltage vectors of secondary additional velocity. Secondary additional braces matching the direction of the vectors in the respective primary rims (as in Figure 1, c).
Rhys. 2. Pressure transformer with two secondary hams. a - diagram; b - 3-phase circuit; vector diagram
The sum of the vectors Ud, Ubd and Ucd is obtained by combining them, respectively, with the connection of the additional vents, and it was assumed that the arrows of the vectors, both primary and secondary, correspond to the starts of the transformator.
The reflex voltage of 3U0 between the end of the vent of phase C and the start of the vent of phase A diagram equals zero.
