SU873345A1 - Rotating transformer connection circuit - Google Patents

Description

(54) SCHEME FOR INCLUSION OF ROTATING TRANSFORMER

one

This invention relates to electromechanical measuring devices.

Known circuits for turning on a rotating transformer (VT) during operation on the load, in which, to preserve the accuracy of the sine-cosine transform, the primary balancing is performed 1.

To perform the primary balancing of the VT, its quadrature winding is shifted by 90 el. hail, with respect to the axis of the excitation winding, closes on a balancing resistance, the active and reactive components of which are equal to the corresponding components of the output resistance of the power source or the circuit that supplies the excitation circuit W.

The primary balancing makes the output impedance of the VT unchanged when the rotor turns, and therefore, when operating on the load, the reproduction accuracy of the sine-cosine dependences is the same as in the absence of loads, i.e. at idle. Practically, primary balancing of the VT directly connected to the power source is performed by short-circuiting the quadrature winding, which provides the output resistances of the VT with some accuracy. But this method of primary balancing is acceptable only with a power source having a low internal resistance or with low accuracy requirements of the VT.

A disadvantage of the known switching circuits of BT is the low accuracy of balancing the BT, the need for special baluns, and a decrease in the accuracy of the BT, while the output resistance of the source supplying the HT is insufficient.

The purpose of the invention is to improve the accuracy of the VT when operating on the load by improving the primary balancing of the VT.

The goal is achieved by the fact that primary

15 quadrature windings are connected to the power source in parallel.

Such an implementation of the VT switching circuit preserves the operability of the entire circuit, but provides accurate primary symmetry of the VT, regardless of the size and constancy of the parameters of the source that supplies the HT. In addition, powering the quadrature winding with the same voltage as the main field winding provides an increase in the transmission coefficient. When using a ring transformer, it is connected between the power supply and the primary windings.

The drawing shows the circuit for switching on the VT when operating on the load.

The switching circuit of the VT, when operating on the load, consists of a power source 1 (induction or electronic), a rotating transformer 2 having two quadrature primary windings BiBz and VCB + connected in parallel to the power source, output windings BT CiCj and KiKz and loads 3 and 4. In the general case, the loads can be RC circuits, windings of other VTs or other circuits. Such a connection of the input windings of the VT, which does not change the essence of its operation to the load, does not provide an ideal primary balancing, regardless of the parameters of the supply circuit, and does not require the use of any balancing devices. In addition, when the output parameters of the power supply change, the balancing does not break. The proposed scheme makes the total output resistances of the secondary windings of the HT constant and, therefore, the connection of the loads does not change the reproduction accuracy of the sinusoidal dependencies of the output voltage of the HT on the angle of rotation of the rotor. Powering both windings leads to an increase in the BT transmission coefficient, increasing it by a factor Vz.

The scheme works as follows.

When applied to the winding AC voltage from source 1, the current of this winding creates a magnetic flux that induces a voltage in the output sinus (CiCz) winding BT proportional to sinoi- and the output cosine (KiK2) winding BT is proportional to coscL, where oL - the angle of rotation of the rotor of the BT in electrical degrees, measured from the position at which the mutual induction of the windings CiCj and BiBz becomes zero.

When supply voltage is applied to the winding of ВВ4. from source 1, since the axis of this winding is shifted by 90 el. hail, relative to the BiB2 winding, on the windings of CiCa and KiKi, with the same reading of the angle oi, respectively, proportional stresses are applied

sin (ci + 90 °) and cos (oi + 90 °).

Thus, on the winding of CiCa, a total voltage proportional to

sinci + sinfci + 90 °) Va sin (oL-f 45 °), a on the KiKa winding

cosci- + cos (ci + 90 °) VScos (/ + 45 °).

Consequently, the output voltages of the VT are proportional to the sine and cosine of the angle of rotation of the rotor with the offset of the origin by 45 ° el. hail, and an increase in amplitude VS

Since both primary circuits are closed

for the same resistance (output resistance of the power supply) in the VT, primary balancing is performed and, therefore, the output resistance of the secondary windings of the VT does not change when the rotor angle of the rotor changes. This ensures that the reproduction of the sinus dependence is preserved when all loads are connected to the secondary circuits.

The scheme of switching on the VT when operating at the load ensures the preservation of accuracy similar to the accuracy of idling. Ensures the constancy of the output resistances of the windings, which makes it possible to fine-tune the RC circuits when using the VT in a single phase phase shifter mode.

The scheme provides an increase in transmission coefficient / 5 times. When performing the BT in the contactless variant by introducing a ring transformer into it, the field winding and the quadrature primary winding located on the VT rotor are connected parallel to the secondary winding of the ring transformer. Such an implementation of contactless VT ensures the constancy of the output resistances of its windings, eliminates phase error and increases its output voltage 1.4 times.

Claims (2)

1. Turn-on diagram of a rotating transformer comprising a power supply and a rotating transformer with two quadrature primary and secondary windings, characterized in that, in order to increase load accuracy, the primary quadrature windings are connected to the power source in parallel. 2. The device according to claim 1, characterized in that it is provided with an annular transformer connected between the output terminals of the power supply and the parallel connected primary quadrature windings. Sources of information taken into account in the examination 1. Khartsev V. F. Electric micromaschins. L., “Energie, 1969, p. 79. 2. Panfilov RK. Principles of construction of the error meters for tracking systems. M., “Energie, 1973, p. 7-8.