SUMMERY OF THE UTILITY MODEL
Based on above-mentioned technique is not enough, the embodiment of the utility model provides an experimental current amplification circuit for replace heavy current rise ware, can bear the high voltage and bear the power frequency voltage for a long time when providing great electric current.
In order to achieve the above object, the embodiment of the present invention provides the following technical solutions:
the utility model discloses an experimental current amplification circuit that uses, the circuit includes: a voltage regulator, a step-up transformer, a current transformer, a compensation inductor and an ammeter,
the output side of voltage regulator with step up transformer's input side is connected, the first terminal ground connection of step up transformer output side, step up transformer's output side second terminal with the first low-voltage terminal of the first secondary side of current transformer is connected, the second low-voltage terminal ground connection of the first secondary side of current transformer, the first low-voltage terminal of the first secondary side of current transformer with be connected between the first low-voltage terminal of the first secondary side of current transformer compensation inductance, the first low-voltage terminal of the second secondary side of current transformer with insert the ampere meter between the second low-voltage terminal of the second secondary side of current transformer.
Optionally, the current transformer further includes: a third secondary side, a second secondary side,
and a second terminal of the output side of the step-up transformer is connected with a first low-voltage terminal of a third secondary side of the current transformer, and a second low-voltage terminal of the third secondary side of the current transformer is grounded.
Optionally, the method further includes: and the primary side of the current transformer is connected into a test circuit.
Optionally, the voltage regulator is a four-layer three-terminal semiconductor device, including: an electric column type voltage regulator, an induction voltage regulator, an auto-coupling voltage regulator and a moving coil type voltage regulator.
Optionally, the input side of the voltage regulator is connected to a power supply.
Optionally, the power supply on the input side of the voltage regulator is 220V mains supply.
Optionally, the step-up transformer is an ac step-up transformer.
Optionally, the current transformer is an electromagnetic current transformer.
The utility model discloses an experimental current amplification circuit that uses, this circuit includes: the device comprises a voltage regulator, a boosting transformer, a current transformer, a compensation inductor and an ammeter. The output side of the voltage regulator is connected with the input side of the boosting transformer, a first terminal of the output side of the boosting transformer is grounded, a second terminal of the output side of the boosting transformer is connected with a first low-voltage terminal of a first secondary side of the current transformer, a second low-voltage terminal of the first secondary side of the current transformer is grounded, a compensation inductor is connected between the first low-voltage terminal of the first secondary side of the current transformer and the first low-voltage terminal of the first secondary side of the current transformer, and an ammeter is connected between the first low-voltage terminal of the second secondary side of the current transformer and the second low-voltage terminal of the second secondary side of the current transformer. The circuit amplifies current through the booster transformer and the current transformer, has the advantages of reasonable structural design, simple layout and stable operation, can effectively replace a large-current booster, and can bear high voltage and long-term power frequency voltage while providing large current.
Detailed Description
The utility model discloses a current amplification circuit for experiments, this paper content can be referred to by technical personnel in the field, and proper improvement technological parameter realizes. It is expressly noted that all such substitutions and modifications which are obvious to a person skilled in the art are deemed to be included in the present invention. The technical solutions and applications of the present invention have been described in terms of preferred embodiments, and it is obvious for those skilled in the art to implement and apply the techniques of the present invention by modifying or appropriately changing and combining the technical solutions and applications described herein without departing from the contents, spirit and scope of the present invention.
When the current transformer is used for a temperature rise test, along with the increase of load impedance, the voltage of a large-current booster is always required to be increased in order to ensure that the load current is constant, and the internal insulation of the large-current booster is damaged due to overhigh voltage, so that the normal use of equipment is influenced, and certain danger is caused to testers. In addition, when the current transformer is used for an insulation thermal stability test, a high-current booster is often used for providing rated continuous thermal current required in the test. Because the rated continuous thermal current and the specified power frequency voltage are simultaneously applied to the tested current transformer in the test, the large-current booster also needs to bear the specified power frequency voltage in the test. The large-current booster does not have the capacity of bearing power frequency voltage for a long time, so that a large insulating platform is required to support the large-current booster in the test, the large-current booster is in a suspension state, and the test difficulty is increased. Meanwhile, the test time is long, and the internal insulation of the large-current booster can be damaged due to the fact that the large-current booster bears power frequency voltage for a long time, so that the test result is influenced. Secondly, the large-current booster can adjust the current only when the power frequency voltage is not applied, which is very inconvenient and greatly reduces the working efficiency of the test.
Therefore, the utility model provides an experimental current amplification circuit for replace above-mentioned heavy current to rise the ware, can effectively avoid the above-mentioned shortcoming that the heavy current rises the ware.
The present invention will be further described with reference to the following examples.
A test current amplifying circuit includes: the device comprises a voltage regulator, a boosting transformer, a current transformer, a compensation inductor and an ammeter. As shown in fig. 1, fig. 1 is a current amplifying circuit for testing provided by the embodiment of the present invention, wherein AT represents a voltage regulator, TT1 represents a step-up transformer, L represents a compensation inductance, CT0 represents a current transformer, a represents an ammeter, 1S1 represents a first low-voltage terminal on a first secondary side of the current transformer, 1S2 represents a second low-voltage terminal on the first secondary side of the current transformer, 2S1 represents a first low-voltage terminal on a second secondary side of the current transformer, 2S2 represents a second low-voltage terminal on the second secondary side of the current transformer, and P1 and P2 represent input terminals connected to a testing circuit.
The output side of voltage regulator AT with the input side of step-up transformer TT1 is connected, step-up transformer TT1 output side first terminal ground connection, step-up transformer TT1 output side second terminal with the first low voltage terminal 1S1 of current transformer CT0 first secondary side is connected, the second low voltage terminal 1S2 of current transformer CT0 first secondary side ground connection, connect compensation inductance L between the first low voltage terminal 1S1 of current transformer CT0 first secondary side and the first low voltage terminal of current transformer CT0 first secondary side 1S2, connect ampere meter A between the first low voltage terminal 2S1 of the second secondary side of current transformer CT0 and the second low voltage terminal 2S2 of the second secondary side of current transformer.
It should be noted that the voltage regulator AT may adjust a magnitude of a current in the test circuit connected to the primary side of the current transformer CT0, the step-up transformer TT1 and the current transformer CT0 may amplify the current, the inductor L may reduce a winding impedance of the first secondary side of the current transformer CT0, and the ammeter a may measure a magnitude of a current in the test circuit connected to the primary side of the current transformer CT 0.
In the ammeter a, the measured current is the secondary side current of the current transformer CT0, and the magnitude of the current in the test circuit connected to the primary side of the current transformer CT0, that is, the magnitude of the current required in the test, can be obtained through inverse transformation ratio calculation.
The size of the compensation inductance L is determined according to performance parameters and experimental parameters of the current transformer CT 0.
Optionally, in a specific embodiment, the current transformer CT0 further includes: a third secondary side. As shown in fig. 2, fig. 2 is a current amplifying circuit for testing according to an embodiment of the present invention, wherein AT represents a voltage regulator, TT1 represents a step-up transformer, L represents a compensation inductance, CT0 represents a current transformer, a represents an ammeter, 1S1 represents a first low-voltage terminal of a first secondary side of the current transformer, 1S2 represents a second low-voltage terminal of the first secondary side of the current transformer, 2S1 represents the first low-voltage terminal of the second secondary side of the current transformer, 2S2 represents the second low-voltage terminal of the second secondary side of the current transformer, 3S1 represents the first low-voltage terminal of a third secondary side of the current transformer, 3S2 represents the second low-voltage terminal of the third secondary side of the current transformer, and P1 and P2 represent input terminals connected to a test circuit.
The second terminal of the output side of the step-up transformer TT1 is connected with the first low voltage terminal of the third secondary side of the current transformer CT0, and the second low voltage terminal of the third secondary side of the current transformer CT0 is grounded.
The third secondary side terminal 3S1 is connected in parallel to the first secondary side terminal 3S2, and the winding impedance on the secondary side of the current transformer CT0, that is, on the input side of the current transformer CT0, can be reduced, thereby increasing the output current.
Optionally, in a specific embodiment, the current amplifying circuit may be connected to a plurality of secondary sides in parallel with the first secondary side, so that the secondary side of the current transformer CT0, that is, the winding impedance at the input side of the current transformer CT0, may be effectively reduced, and the output current may be increased. What of the number of the secondary side connected in parallel belongs to the technical scheme of the utility model, and does not break away from the protection scope of the utility model.
Optionally, the method further includes: the primary side of the current transformer CT0 is connected to a test circuit.
Optionally, the test circuit may be a temperature rise test circuit or an insulation thermal stability test circuit.
Optionally, the voltage regulator AT is a four-layer three-terminal semiconductor device, including: an electric column type voltage regulator, an induction voltage regulator, an auto-coupling voltage regulator and a moving coil type voltage regulator.
It should be noted that the voltage regulator AT can adjust the output voltage, and the voltage and the current change accordingly, so as to achieve the current required by the test circuit.
Optionally, the second side of the voltage regulator AT is connected to a power supply.
Optionally, the power supply on the input side of the voltage regulator AT may be 220V mains.
Optionally, the step-up transformer TT1 may be an ac step-up transformer.
The ac step-up transformer is used in a circuit in which an ac power supply is used.
Optionally, the current transformer CT0 may be an electromagnetic current transformer.
Optionally, the current transformer CT0 increases the current by the principle of electromagnetic induction.
Optionally, in a specific embodiment, during the test, according to the current reading of the ammeter a, the test may be started after the ammeter reaches the current required by the test through the voltage regulator AT.
Compare with current rising equipment, the utility model has the advantages of it is following: the utility model has the advantages of reasonable design, the overall arrangement is simple, the operation is stable, can satisfy each voltage level current transformer's temperature-rise test demand, do not need heavy current to rise the current ware when carrying out current transformer insulation thermal stability test, the insulation support that makes heavy current rise the current ware and be in the suspended state has also been avoided, can be under the condition that power frequency voltage applyed simultaneously, required electric current in the direct regulation experiment, great improvement experimental work efficiency, be particularly useful for the higher and more condition of its secondary winding of current transformer equipment maximum voltage, and satisfy in the GB20840.2-2014 standard about insulation thermal stability test's requirement.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.