PL206558B1 - Electronic electricity meter - Google Patents

Description

REPUBLIC

POLAND

Patent Office of the Republic of Poland (12) PATENT DESCRIPTION (19) PL (11) 206558 (13) B1 (21) Application number: 372912 ^{(51) Int.Cl.}

G01R 11/24 (2006.01) (22) Date of notification: 17/02/2005 (54)

Electronic electricity meter

(43) Application was announced: 21.08.2006 BUP 17/06 (73) The right holder of the patent: RESEARCH AND DEVELOPMENT CONSORTIUM MAGNETO M. SOIŃSKI G. RYGAŁ R. RYGAŁ SPÓŁKA JAWNA, Częstochowa, PL (45) The grant of the patent was announced: August 31, 2010 WUP 08/10 (72) Inventor (s): ROBERT PYTLECH, Częstochowa, PL ROMAN RYGAŁ, Częstochowa, PL MARIAN SOIŃSKI, Częstochowa, PL

PL 206 558 B1

Description of the invention

The subject of the invention is an electronic electricity meter designed for accurate billing of the actual electricity consumption between its consumer and supplier.

For this purpose, an electric energy meter is known, from the European patent specification No. EP0085769, provided with a sensor in the form of an external shunt connected to an internal current sensor - a current shunt.

The sensor structure consists of an autotransformer that supplies voltage and a secondary winding connected in series with the current sensor - a current shunt.

The operation of the device according to the invention, due to the presence of an external magnetic field, results in the disconnection of the circuit transmitting electricity to the consumer.

Another known electronic electricity meter consists of a housing with a terminal box, a measuring system and a measurement processing module. The measuring system is a current transformer, separate for each phase, the secondary winding of which is connected to the measurement and processing module. The current transformer is a transformer with a closed core, most often toroidal made of fittings or coiled with a soft ferromagnetic strip, equipped with one primary winding with low resistance and a secondary winding.

Also known from the Polish patent application description No. 320978 is a meter having a measured value converter and a measurement quantity processing system.

In the event of an external magnetic field influencing the electronic meter, the magnetic core of the current transformer becomes saturated. As a result of this action, the value of the current flowing in the secondary circuit drops, even though the same value of current flows continuously in the primary circuit. As a result, the meter does not show energy consumption, despite the actual energy consumption, or shows a significantly underestimated value.

The object of the solution according to the invention is to develop an electric energy meter that would be resistant to the harmful effects of an external magnetic field.

The essence of the meter according to the invention is that its measuring structure is a current transformer, the primary winding of which is connected to the shunt, and the output from the shunt is connected to the measurement and processing module.

It is advantageous to have a shunt inside the current transformer, which is its primary winding.

Placing the shunt inside the current transformer reduces the overall dimensions of the construction of the electric energy meter.

The solution according to the invention is characterized by effective and simple protection of the electricity meter against the influence of an external magnetic field on its indications.

The subject of the invention in an exemplary embodiment is reproduced in the drawing, in which Fig. 1 shows a schematic diagram of an electronic electricity meter in perspective view, and Fig. 2 - a schematic-block diagram of a measuring system in which the primary winding of the current transformer has a shunt connected.

The electronic electricity meter has a casing 1 with a terminal box 2, in which there is a measuring system in the form of a current transformer 3. The secondary winding of the current transformer 3 is connected to the measurement and processing module 4, while its primary winding 5 is connected to the shunt 6. The output from the shunt 6 is connected to the measurement and processing module 4.

When electricity is consumed by the user, electricity flows in the meter's current path. The current value is measured through the current transformer and the shunt, and then both values are compared with each other by the measurement and processing module. If the measured indications are equal to the assumed accuracy level, then the current value measured with a current transformer is used for electric energy measurements. When a magnetic field appears near the meter, the current values measured by the current transformer may differ significantly from the current values measured by the shunt. Then the measurement and processing module determines the electric energy consumption based on the value of the current measured by the shunt.

PL 206 558 B1

Claims (2)

Patent claims 1. Electronic electricity meter with a measuring system equipped with a shunt and a current transformer, characterized in that the measuring structure is a current transformer (3), the primary winding of which is connected to the shunt (6), and the input from the shunt (6) is connected to a measurement and processing module (4). 2. An electronic counter according to claim A shunt (6), which constitutes its primary winding, is located inside the current transformer (3).