SU935803A1 - Galvanomagnetic measuring converter of power - Google Patents

Description

The invention relates to galvanomagnetic power transducers and is intended for use in automatic control devices, monitoring and control of energy systems, in particular for controlling the total power generated by several power plant units.

Galvanomagnetic transducers are known. They are intended for oscillography or power measurement in three-phase circuits, in a voltage circuit containing an isolating transformer, and in a current circuit - a Hall multiplier (.IJ.

The disadvantage of these transducers is the low measurement accuracy determined by the spread of the Hall sensor parameters.

The galvanometric measuring power converter is also known. containing a Hall sensor located in the gap of the differential magnetic circuit with windings placed on its middle rod, the ends of each of which are the first input / II converter 12J.

The main disadvantage of the well-known power meter is the significant magnitude of the fundamental error due to the use of several Hall sensors when measuring the power of several generators.

The purpose of the invention is to improve the measurement accuracy of the total power of several generators.

The goal is achieved

10 in that a power sensor containing a Hall sensor placed in the gap of the differential magnetic circuit with windings placed on its middle rod, the conclusions of each of which are the first converter, is included several connected according to the primary windings and one secondary, each winding is made

20 in the form of two equal parts placed on different arms of the differential magnetic circuit, the secondary winding leads are connected to the current of the Hall sensor, and the outputs of each primary winding are connected to the outputs of the respective generators.

Claims (2)

The drawing shows a circuit diagram of the proposed device. The device consists of a Hall sensor 1 placed in the gap of the differential magnetic circuit 2, which is an W-shaped core, on which windings 3 are placed on the middle rod, conclusions 4 each of which are the nepBHNm inputs of the converter, are somewhat connected according to the primary windings 5 and one secondary b, each of the voltages 5 and 6 being made in the form of two equal parts placed on different arms of the differential magnetic conductor 2, and the outputs of each primary winding 5 are the second inputs of the converter. The device works as follows. When 3 windings are off, i.e. in the absence of a magnetic flux, the ES is proportional to the voltage (or current) of the control circuits, through the current terminals of the Hall sensor 1 current flows proportional to the currents (or voltage) of the monitored circuits. When currents flow from the monitored circuits, a magnetic flux is created in each of the primary windings 5. (As they are turned on according to, the directions of all magnetic fluxes of the windings 5 coincide and create a total flux F. In the secondary winding, EMF from the total magnetic flux F. at the output of the Hall sensor 1, since the flows in the middle rod of the differential magnetic field 2 generated by the half-winding 5 mutually cancel each other out. When the windings .3 are connected to the controlled circuit, i.e. A voltage proportional to the total power of the monitored circuits (synchronous generators) arises at the output of the Hall sensor 1. Indeed, with the simultaneous influence of magnetic fluxes F and Fd (see drawing) in the left arm of the differential magnetic circuit, the total flow is F, + F and in the right - Ф, + Ф sn 2 t On the average rod 1 - (- Ф - ФФ2д) Ф because (i.e, a magnetic field acts on the Hall sensor 1 proportional to the measured voltage of the monitored circuits. (or current). In the secondary winding in the power supply circuit of the Hall sensor, the following EMFs are induced: in the left arm e. E2 - e; in the right arm e, e, + e The Hall sensor 1 is affected by the EMF, proportional to the sum of the currents (or voltages) of the monitored circuits (synchronous generators), and it is equal to .e-i; i + e2 + «- 2e2. . + e „(i.e., the sensor is affected by a supply voltage proportional only to the sum of the currents (or voltage) of the monitored circuits (synchronous generators). Measuring power converters for measuring reactive power can be obtained from the total active power converter (described above) with appropriate switching of winding groups to monitored circuits. A full-power measuring transducer can be obtained from a Power Transducer (described above) using rectifying elements. The anomagnetic total power measuring transducer can be used not only for measuring power in three-phase circuits, but also in single-phase and multi-phase circuits. Compared with the known ones, the proposed converter (iy max power can bring the accuracy class to 0.5 due to elimination of the error caused by the spread of the parameters of the Hall sensors, and improve the operating parameters of the control devices. Formula of the invention Galvanomagnetic power transducer, containing a Hall sensor, p placed in the gap of a differential magnetic circuit with: windings placed on its middle rod, the conclusions of which are the first inputs of the converter, characterized in that, in order to improve the measurement accuracy of the total power of several generators, several included according to the primary windings and one is secondary, with each winding made in the form of two equal parts placed on different arms of the differential magnetic circuit, the conclusions of the secondary winding are connected to current inputs g Atchik Hall, and the output of each primary 06MOT.KI connected to the outputs of the respective generators. Sources of information taken into account in the examination 1. Handbook of electrical measuring instruments. Ed. K. K. I. Lyunina, L., 1977, p. 675. 2. Authors certificate of the USSR 682837, cl. G 01 R 21/06, publ. 1973 (prototype).