SU58791A1 - Apparatus for producing a voltage proportional to the product of two variable electrical quantities - Google Patents

Description

To solve many problems of electrical measuring equipment and automatics, it is necessary to obtain an electrical quantity equal to the product of two magnitudes of alternating current or voltage or a square of similar quantities.

Already known are electrical devices based on the use of electrical transformers, which, in addition to the two main windings, are also equipped with an additional iodine magnet Osh, which is surrounded by MOSC, fed by a constant current. The bias changes the magnetic permeability of the iron of the transformer's heart, as a result of which the voltage of the non-transitory current transfered by the Imitated in the secondary winding changes. By using various artificial connection circuits, it is possible to achieve that the variable 1 April on the secondary winding of the transformer, within certain limits, is proportional to the ionic value of the 1st magnetic bias current. Such devices are widely used. They are used in the first size technique, mainly when measured by indirect methods of high-current direct currents. In the proposed device according to the invention, the device also uses a similar method. As the applicant points out, when applying to the primary winding of an alternating voltage transformer, and biasing one, the constant or direct first alternating voltage, there is a possibility to obtain the voltage in the secondary winding from a certain range transformer proportional to the product of two electrical quantities supplied to the first two windings.

Thus, a feature of the device proposed in accordance with the invention is the use of such a transformer with subdivision to obtain the product of two electrical quantities or the construction of R squared electrical quantities 1.

In FIG. 1 1; yu | razhaag scheme

connections of the proposed device, FIG. 2,3 and 4 - various modifications of the indicated scheme.

Transformer 7 (fig. 1) is equipped with three independent windings: primary 5, to which one of the alternating voltages is directly supplied, and biasing 2, to which the second alternating voltage is applied (or also the first voltage, in the case when square one and the same electrical value) through the rectifier system 3. A transformer is switched on in the secondary winding 4 of the transformer. As indicated by the applicant, in the absence of bias, the alternating voltage in the secondary winding of the transformer is zero, which is a prerequisite for the secondary voltage to be proportional to the product of two quantities, it is possible to use a number of known measuring circuits transformers with magnetization. For example, in the diagram shown in FIG. 2, a transformer 1 with a branched core of a special form is shown. The two halves of the AC primary winding 2 and 3 are wound on the two side branches of the core in such a way that the magnetic fluxes created by them in the central part of the core are mutually compensated. Thus, in the secondary winding 4, the alternating voltage will be absent. With an additional constant biasing of one of the side rods with direct current flowing through the winding 5, the equilibrium and magnetic fluxes are disturbed and in the secondary winding 4 there is an alternating voltage.

An “ed” device can be used in various practice cases. FIG. 3 shows one possible use case. The circuit is intended to obtain a constant voltage proportional to the magnitude of the active or reactive power in the circuit of the alternating current, which can be used in measuring devices for telemetry, summing up several iipHbor readings, adjusting power, etc. The circuit consists (Fig 3) from two devices 2, 2, similar to those described above i

each intended to obtain voltages proportional to the square of the amplitude value of the input variable voltages. These voltages are supplied from the secondary winding of the current transformer 1 connected to the network 5 with a controlled load. The middle point of the secondary winding of the transformer 1 is connected to one of the wires of the network, which is thus connected to the device 2, 2. The second wire of the network is directly connected to the same devices. With this connection scheme, as shown in FIG. 3, the geometrical sum and difference of the voltage vectors U and the gok / controlled circuit 5 are supplied to devices 2 and 2, respectively.

At the same time, the amplitudes of the recurring quoting vectors are equal; for the sum

/ 0 - t- / 2 - {- 2L7cos for the difference

 (f-./2 2L / cos-f

At the output of devices 2, 2 square) amplitudes:

/7-Ч--/--Ь267со5.р f / --- Г- 2 Wcosf

After straightening in lpl mig.1lmi 3 and C of capacitance 4 capacitance 4, we obtain the voltage of direct current, f ponopmii; the total algebraic times of 1 quadr.; fOB amplitudes, i.e.

Taki image: “)., You can get HJ1 performance, proportional to the active power. ) 10th power reagent can be obtained by putting the yurota of the vector pa 90.

D.15. student tension, .ioalyuyogo active. power, .can also serve as the schema shown in fig. 4. It also uses a 3 current transformer 1, which is included in a controlled

i network 5. Middle point of secondary winding

I is connected to one of the network wires, and the end of the network, via rectifier 2 and opposite 3, to the second wire of the same network. In this case, the voltage

I resistance 3 b} are proportional

; for 1: 0, the sum of the voltages and and voltages proportional to the current I, and for the other, their differences.

If we choose the amplitude U significantly larger than the amplitude I, then with some error we have:

((74- / cos7 and and- fcosf

Voltage difference across resistances 3

U. {U + fcos :) - (7- / cosj) 2U - / cos-.

To obtain a voltage proportional to the active power, the device 4 described above is applied, the output of which is a voltage proportional to the product of two summed to the electrical quantities, namely: / cos (obtained as described above) k and, as a result voltage:

and Ci / cos y 1 {W, where VV is mosh.

Subject and c oreg sn and

Claims (4)

1. A device for producing a voltage proportional to the product of two variable electrical quantities, characterized by the use of a bias transformer, the primary winding of which is intended to supply or voltage proportional to one of the electrical quantities, and the biasing constant power supply 1M or rectified current proportional to a different electrical value so that by the value of the resulting voltage on the secondary winding of the transformer it was possible to determine the value produced and both greatness. 2. Vidoiz. The device change according to claim 1, characterized in that, in order to square the electric quantity, both the primary and the magnetized windings are powered by a voltage proportional to the quantity being studied. 3. The form of the device according to Claims 1 and 2, characterized by using two identical instruments, giving a square in the amplitude of the alternating voltage and included in the alternating current circuit in such a way that one of them is supplied with a reoMeTpical sum, and to another, the geometric difference of the current and voltage vectors, with the goal that as a result of algebraic subtraction we obtain: voltage can be obtained voltage proportional to the value of the active power, 4. Form of the device but II, p. 1 and 2, with the use of a transformer with bias magnetization, in which the AC winding is designed to supply a voltage to the voltage of the installed circuit, and the magnetised winding is used to supply the rectified current in the transformer circuit, the middle point of which It is connected to one of the network wires, and the extreme ones, through the rectified gol and resistance, from the second, 1m of the same network.