SU95798A1 - Device for measuring AC voltage deviation from nominal value - Google Patents

Description

In the AC circuits in which the stub 1; 1 is used, it is 1pred 11, to assess the degree of stabilization, it is important to know (with sufficient accuracy) the magnitude of the deviation of the bearing from the nominal value.

The object of the present invention is a device for measuring the deviations of an AC current from a nominal value with an accuracy of the order of 0.05%, consisting of a two-frame differential measuring device, a converter transformer with a rectifier for bending a rectified measured voltage of one out of the framework of said device and an auxiliary source of direct current for applying voltage to another frame.

In the proposed device, in order to set the set value of the working voltage according to the indication of the arrow of a two-frame device at an open-cell voltage, the additional resistance applied to the circuit of the auxiliary DC source is applied in such a way that it shortens with the mainstream 1111 main measurements.

On e, chektrichesko1 1 scheme of the proposed device; Y-transformer, 2 and.-Dry rectifiers, 4 and 5-resistance resistance, 6-over-resistance, 7 and 8-shunt resistance, 9 N W-frame differential measuring instrument. At / - switch. 12-auxiliary source of direct current, /.- relay, 1-4-contact relay.

The test voltage is applied to the primary winding of a transformer having two secondary windings. One of them through the benchmark resistance 4 feeds the dry rectifier 2. The other feeds the relay coil through the dry rectifier. The rectified voltage from rectifier 2 is applied to the frame W of the differential frame device. Box 9 through variable resistance 5 and optionally .95798-2 -

Its resistance 6 is powered by a direct current from an auxiliary source 12. The frames are shutened by 1pres 7 and 8 resistors in order to reduce the possible asymmetry of the currents in them. Vrayadayushie moments created by the two frames of the device, directed towards each other.

The principle of operation of the device is as follows: the switch Y / is set in the "compensation" position, changing the magnitude of the variable condition 5 so that the operating current flows through frame 9, the magnitude of which is fixed by the red mark on the instrument scale; then the switch // is set to the measurement position (in this case the additional simultaneous indication 6 is short-circuited), the polarity of frame 9 is changed, and the test voltage is applied to the frame JO.

At a certain value of the nominal voltage corresponding to the measured value of the change in voltage, the instrument's pointer is set in the middle of the scale by changing the voltage value 4, which corresponds to a zero value of the voltage change.

Disconnection of the voltage to one side or the other will correspond to changes in nominal voltage. These changes can be applied directly to the scale as a percentage of the nominal voltage value. By appropriate selection of parameters, the whole scale can be obtained with the measurement limit n: 5% and with a division value of 0.1%. Such a significant increase in sensitivity is achieved by the fact that when the measurement is carried out, the resistance 6 is shortened.

In order for the device not to receive damage from a one-sided connection, which is possible when measuring the switch L and without the power supply from the non-alternating current, the device has a relay / which, with its contacts M, turns on the auxiliary source 12 only in the presence of alternating voltage.

Ire d m and h o b r e p e

A device for measuring the deviation of a ripple current from the nominal value, consisting of a two-frame differential measuring device, a voltage transformer with a spreader for supplying a rectified measured voltage to one of the frames of the pointing device and an auxiliary source and constant current, supplying the frame to another frame, which is tolchuyuyees that in order to install a given one, I carried out the first working pattern but the indication of the arrow of the same two-frame device and when opened, measured ii vsnomogatelyyugo source circuit in Jost direct current introduced donolnitelnoe resistance zakoraMjHiaeMoe npii performing main measurement.

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