SU1486964A1 - Device for synthetic disconnecting testing of ac disconnecting switches - Google Patents

Description

The invention relates to electrical test equipment. The device contains a source of direct current 1, an inductive drive 3, a disconnecting element 5, a high voltage circuit 6 and a block 7 for the formation of a recovering voltage.

The introduction of the circuit breaker 2, the contactor 11 and the blocks 12 and 13 of the control increases the reliability of the device and the reliability of the test results.

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The invention relates to electrical testing equipment and can be used for synthetic testing of alternating current switches for breaking capacity.

The purpose of the invention is to improve the reliability of the device and the reliability of the test results.

The drawing shows the block diagram of the device.

The device contains a source of DC 1, a circuit breaker 2, an inductive drive 3, an auxiliary inductor 4, a disconnecting element 5, a high voltage circuit 6, a recovery voltage generation unit 7, the first 8 and second 9 terminals for connecting the test object, the 20 circuit breaker , an additional contactor 11, the first 12 and second 13 control units, the first output of the contactor 10 is connected to the first output of the inductor 4. The second output 25 of the latter is connected to the first output of the tripping element 5, the second output of which is connected to terminal 8 and the first outputs of the unit 7 and the high voltage circuit 6. The second terminals of the latter are connected to the second terminal of the contactor 10, terminal 9 and the first terminal of source 1, the second terminal of which is connected to the first terminal of the breaker 2. The second terminal of the latter is connected to the first 5 terminals of the accumulator 3 and the contactor 11, the second terminals of which are connected respectively with the second output of the source 1 and the first output of the coil

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4 inductance. The outputs of the blocks 12 and 13 are connected to the control input, respectively, of the contactor 11 and the disconnector 2.

The device works as follows

at once.

At the initial moment, the contacts of the additional contactor 11 are open. Therefore, when voltage is applied to the circuit, the current flows only in a circuit consisting of a direct current source 1, an inductive energy storage device 3 and a circuit breaker 2. Only an inductive energy storage device 3 is charged. When the current reaches the required value in it, the contact clock of the additional contactor 11 closes, and a little later the contacts of the breaker 2 open. As a result,

consisting of an additional contactor 11, auxiliary inductance coil 4, the disconnecting element 5 and the test switch connected to terminals 8 and 9, the specified current begins to flow. This current first drops to zero, and then reverses its direction and reaches a maximum value at the moment when the arc in the breaker 2 goes out and, thus, separates the direct current source 1 from the circuit. At the same time, the contacts of the tripping element 5 and the test switch are opened and electric arcs appear in them. !

The next moment the contacts of the contactor 10 close, which shunts the auxiliary inductance coil 4, the disconnecting element 5 and the test switch connected to terminals 8 and 9. But since the current through the auxiliary inductance coil 4 cannot abruptly stop, it reaches zero after a certain of time. The rate of decline of the current 13 defined άίε

divided by the expression -

from bf

The total voltage drop (and _? ) On the arcs of the disconnecting element 5 and the test switch ~ is almost constant at a current of> 3 kA; B is the inductance value of the auxiliary inductance coil 4 for a given test switch — a constant value. Given the constancy of the value of άΐ / 81 :, the nature of the decline can be taken almost straightforward.

Derivative <Н / сИ: is assumed to be equal to the derivative of sinusoidal current of industrial frequency c. the moment of his crossing zero. Knowing Πΐ / Πί and the voltage drop across the arcs, find the required value of the auxiliary inductance coil 4,

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The indicated process of obtaining a variable in magnitude and direction of the current of industrial frequency in the switch being tested provides conditions for supplying energy to the arc of the switch being tested approximately the same as in test facilities in which shock generators or electric networks are used as current source.

At the moment of time preceding the moment when the current approaches zero, the switch under test is exposed to a high voltage circuit 6 with a current of increased frequency. Thus, from this point on, the total current flows through the test switch, and only the current component flows through the tripping element 5. When this component of the current in the tripping element 5 passes through a zero value and the arc in it goes out, the test switch is turned on in the high voltage circuit 6 and all further processes are determined only by the parameters of this circuit. After extinguishing the arc in the test switch, the voltage is restored at its contacts, which is determined by the elements of the formation unit 7.

Claims (1)

Claim Device for synthetic testing of AC circuit breakers for breaking capacity, containing a high voltage circuit, regenerative voltage generating unit, terminals for connecting the test object, a disconnecting element, auxiliary inductance coil, a contactor, a DC source and an inductive 1486964 ten 15 20 25 thirty 35 the storage device, the first output of the contactor is connected to the first output of the auxiliary inductor, the second output of which is connected to the first output of the tripping element, the second output of which is connected to the first terminal for connecting the test object and the first terminals of the regenerating voltage generation unit and the high voltage circuit, the second outputs of which connected to the second output of the contactor, the second terminal for connecting the test object and the first output of the DC source, characterized in that Improving the reliability of the device and the reliability of the test results, a breaker, an additional contactor and two control units are entered into it, the second output of the current source is connected to the first output of the breaker, the second output of which is connected to the first terminals of the inductive drive and the additional contactor, the second terminals of which are connected respectively with the second output of the DC source and the first output of the auxiliary inductor, while the outputs of the first and second control units are connected En with control inputs, respectively, of an additional contactor and breaker.