CN87202552U

CN87202552U - Adjustable mutual-inductor

Info

Publication number: CN87202552U
Application number: CN 87202552
Authority: CN
Inventors: 彭平
Original assignee: Individual
Current assignee: Individual
Priority date: 1987-02-27
Filing date: 1987-02-27
Publication date: 1988-09-14

Abstract

The existing adjustable mutual inductors produced are all electronic compensating type. An adjustable mutual inductor of the utility model can make use of adjusting resistance and capacitance to change the number of compensating turn so as to adjust the change ratio error and the angle difference of the mutual inductor. For example user makes use of changing the number of compensating turn to adjust the change ratio error of the voltage mutual inductor and user can use the method of changing compensation capacitor to change the angle difference of the voltage mutual inductor. The product is adapted for matching various ammeters, voltmeters, power meters, electrical meters, electric relay, and transmitter. Compared with a circuit without using the mutual inductor, the error of the measure circuit formed by using the mutual inductor of the product is smaller.

Description

Adjustable mutual-inductor

The present invention relates to a kind of adjustable instrument transformer, particularly the adjustable instrument transformer of single phase alternating current (A.C.).

At present; domesticly do not make adjustable instrument transformer as yet, the external adjustable instrument transformer of producing is the electronic compensation formula, and the instrument transformer of charged sub-compensating circuit is subjected to the restriction of former device and protective circuit reliability; the failure rate ratio is the instrument transformer height of charged sub-compensating circuit not, and needs independent power supply circuits.

The objective of the invention is to make the adjustable instrument transformer of charged magnetic compensation circuit, simplified structure improves reliability.

In brief: the adjustment circuit by instrument transformer of the present invention is: ratio error and phase angle error that the method for utilizing adjustment resistance, electric capacity, change to compensate the number of turn is regulated instrument transformer, as use adjustable resistance to adjust the ratio error of current transformer, and adjust the phase angle error of current transformer with adjustable resistance, use the method that changes the bucking coil number of turn, the variation error of regulation voltage instrument transformer, and change the potential transformer phase angle error with the method that changes building-out capacitor.

According to adjustable instrument transformer of the present invention, have following advantage: with the method that changes resistance, electric capacity, the number of turn instrument transformer is adjusted, not charged sub-compensating circuit, simple structure, good reliability, cost is low; Have independently phase angle error adjusting device, make instrument transformer be suitable for various loads.

Fig. 1 is adjustable current transformer circuit schematic diagram;

Fig. 2 is adjustable voltage transformer circuit schematic diagram;

Referring now to Fig. 1 and Fig. 2 the present invention is elaborated.In Fig. 1, W _A1Elementary for current transformer, can be one or more windings; W _A2Secondary for current transformer can be one or more windings.W _A3Be the compensation winding identical with sub-quantities, and and secondary parallel connection.And W _A3The R of series connection _A1Be variable resistance, levelling R _A1Can change the variation error of current transformer, W _A4Be the phase angle error compensation winding identical with sub-quantities, and W _A4The R of series connection _A2Be variable resistance, adjust R _A2Can change the phase angle error of current transformer.

In Fig. 2, W _V1For the voltage transformer that one or more windings constitute elementary, W _V2For the voltage transformer that constitutes by one or more windings secondary, W _V3For identical with secondary number and with the compensation winding of secondary formation mutual inductance, be tapped coil, K is the multiple spot diverter switch, switches compensation group W by multiple spot diverter switch K _V3Tap, change compensation winding W _V3The number of turn, can change the ratio error of voltage transformer, C is that variable capacitor is parallel to secondary winding W _V2On, change electric capacity and can adjust the potential transformer phase angle error.

So far, shown and introduced a kind of adjustable mutual-inductor, and disclose two kinds the most frequently used in the transformer: the embodiment of current transformer and voltage transformer. It has not only satisfied the adjustable requirement of mutual inductor ratio, and with independent angular difference adjusting device. So not only be suitable for ohmic load, also be suitable for inductance or capacitive load, be applicable to the cooperation ammeter, voltmeter, power meter, kilowatt-hour meter, relay and transmitter. It not only can bring additive error, and passes through the systematic error of adjusting device Contrary compensation instrument. As long as the matching instrument stable performance, the measuring circuit that is made up of this transformer and matching instrument can be littler than the measurement mechanism error of not using transformer. Littler than the error of 0.5 grade standard kilowatt-hour meter such as the synthetic overall error of the kilowatt-hour meter verifying attachment that uses this transformer and 0.5 grade standard kilowatt-hour meter to produce, can produce 0.5 grade device. Armature winding involved in the present invention, secondary windings, compensation winding, variable resistance, tunable capacitor etc. all are that this professional ordinary person is known, and therefore short of category of the present invention and the Spirit Essence of leaving can make a variety of changes and replace.

Claims

1, a kind of current transformer is by elementary winding [W _A1] and secondary winding [W _A2] constitute, it is characterized in that, on secondary winding, have a compensation winding that connects in parallel and with [W _A3] variable resistance [R that is connected in series _A1], adjust [R _A1] can change the ratio error of current transformer; Also has phase angle error compensation winding [W _A4] and with [W _A4] series connection variable resistance [R _A2], adjust [R _A2] can change the phase angle error of current transformer.

2, a kind of voltage transformer is by elementary winding (W _V1) and secondary winding (W _V2) constitute, it is characterized in that the compensation winding (W with secondary formation mutual inductance is arranged _V3) and multiple spot diverter switch (K), switch compensation winding (W by diverter switch _V3) tap change compensation winding (W _V3) the number of turn, can change the ratio error of voltage transformer.Also have and secondary winding (W _V2) building-out capacitor C in parallel, change electric capacity and can adjust the potential transformer phase angle error.