阅读说明：本技术 一种非侵入式计量电流和电压的设备 (Non-invasive current and voltage metering device ) 是由 徐奇梁 许鹰 于 2019-09-29 设计创作，主要内容包括：本发明涉及一种非侵入式计量电流和电压的设备,该设备安装在待测电流和电压的线缆上；其特征在于：包括印刷电路、电容式感应器和磁感应装置；本发明中采用非侵入式,非电测量的方式,通过测量量载电导线周围的电场和磁场,来计量输电,配电,和用电情况；安装和使用该装置,无论对输配电,还是用电侧的正常工作都不产生任何影响；此装置无需对载电导体有物理理接触；通过测量磁场的装置可以支持高频频宽的测量,还能兼容直流和交流的测量。(The invention relates to a non-invasive current and voltage metering device, which is arranged on a cable for current and voltage to be measured; the method is characterized in that: comprises a printed circuit, a capacitance type inductor and a magnetic induction device; the invention adopts a non-invasive and non-electric measurement mode to measure the conditions of power transmission, power distribution and power consumption by measuring the electric field and the magnetic field around the power-carrying lead; the installation and the use of the device do not affect the normal work of power transmission and distribution or power utilization sides; the device does not require physical contact to the current carrying conductor; the device for measuring the magnetic field can support the measurement of high-frequency bandwidth and is compatible with the measurement of direct current and alternating current.)

1. A non-invasive current and voltage measuring device is arranged on a cable for measuring current and voltage; the method is characterized in that: comprises a printed circuit, a capacitance type inductor and a magnetic induction device;

the capacitance type inductor and the magnetic induction device are both arranged on a printed circuit, and an analog signal processing circuit is arranged on the printed circuit; the capacitance type inductor is provided with a pair of capacitors and is respectively positioned on a zero line and a live line of the current to be measured; the magnetic induction device comprises at least one magnetic inductor.

2. The apparatus of claim 1 for non-invasively metering current and voltage, wherein: the magnetic induction device comprises a magnetic inductor, a magnetic core, an auxiliary variable coil, an amplifier and an auxiliary variable coil driver; the magnetic core is of a circular ring structure, a gap is formed in the magnetic core, the magnetic inductor is arranged at the gap of the magnetic core, and the auxiliary variable coil is wound on the magnetic core; one end of the amplifier is connected with the magnetic inductor through a wire, the other end of the amplifier is connected with one end of the auxiliary variable coil driver, the other end of the auxiliary variable coil driver is connected to one end of the auxiliary variable coil, the other end of the auxiliary variable coil is connected to the printed circuit, and a load resistor is connected to a circuit, connected with the printed circuit, of the auxiliary variable coil in parallel.

3. The apparatus of claim 1 for non-invasively metering current and voltage, wherein: the magnetic inductor among the magnetic induction device has two, the interval fixed setting between this pair of magnetic inductor, this is installed on printed circuit to the magnetic inductor.

4. The apparatus of claim 1 for non-invasively metering current and voltage, wherein: the magnetic inductor is a giant magneto-resistance GMR or tunneling magneto-resistance TMR magnetic field inductor.

Technical Field

The invention relates to the field of power measurement, in particular to a non-invasive current and voltage metering device.

Background

The current measurement is divided into an invasive method and a non-invasive method, the invasive current measurement is based on the ohm law, and has the advantages of low cost, high precision, small volume, obvious defect, large temperature drift, difficult selection of precision resistor and no isolation effect. The non-invasive current measurement mainly comprises methods such as a current transformer and a Hall sensor. The current transformer is the most widely used current measuring mode in the electric energy metering device in China at present.

The current transformer mainly comprises a primary winding, a secondary winding, an iron core, insulation between the windings and the iron core and a shell, and the working principle is similar to that of a transformer; the current transformer has simple principle and convenient use, can measure very large current, consumes little power and is the inductor which is used most in the current large-current electronic electric energy meter. The normal output of domestic mature commercial products is 5A or 1A, and the electromagnetic relay can provide enough driving capability.

However, because these products can only test some lines of low voltage and low voltage in low altitude, but the existing current transformer has the problems of small dynamic range, narrow frequency band, poor anti-interference performance and poor measurement accuracy in the overall measurement of current and voltage in the high voltage and high current circuit in high altitude.

Disclosure of Invention

The technical problem to be solved by the invention is to provide a device for measuring current and voltage in an intrusive mode, which can solve the problems of inconvenience brought by traditional intrusive current and voltage measurement and the problems of small measurement dynamic range, narrow frequency band, poor anti-interference performance and poor measurement accuracy of the current transformer adopted by the existing non-intrusive current and voltage measurement.

In order to solve the technical problems, the technical scheme of the invention is as follows: a non-invasive current and voltage measuring device is arranged on a cable for measuring current and voltage; the innovation points are as follows: comprises a printed circuit, a capacitance type inductor and a magnetic induction device;

the capacitance type inductor and the magnetic induction device are both arranged on a printed circuit, and an analog signal processing circuit is arranged on the printed circuit; the capacitance type inductor is provided with a pair of capacitors and is respectively positioned on a zero line and a live line of the current to be measured; the magnetic induction device comprises at least one magnetic inductor.

Furthermore, the magnetic induction device comprises a magnetic inductor, a magnetic core, an auxiliary variable coil, an amplifier and an auxiliary variable coil driver; the magnetic core is of a circular ring structure, a gap is formed in the magnetic core, the magnetic inductor is arranged at the gap of the magnetic core, and the auxiliary variable coil is wound on the magnetic core; one end of the amplifier is connected with the magnetic inductor through a wire, the other end of the amplifier is connected with one end of the auxiliary variable coil driver, the other end of the auxiliary variable coil driver is connected to one end of the auxiliary variable coil, the other end of the auxiliary variable coil is connected to the printed circuit, and a load resistor is connected to a circuit, connected with the printed circuit, of the auxiliary variable coil in parallel.

Further, the number of the magnetic inductors in the magnetic induction device is two, the distance between the pair of magnetic inductors is fixedly arranged, and the pair of magnetic inductors are arranged on the printed circuit board.

Further, the magnetic inductor is a giant magneto-resistance GMR or tunneling magneto-resistance TMR magnetic field inductor.

The invention has the advantages that:

1) The invention adopts a non-invasive and non-electric measurement mode to measure the conditions of power transmission, power distribution and power consumption by measuring the electric field and the magnetic field around the power-carrying lead; the installation and the use of the device do not affect the normal work of power transmission and distribution or power utilization sides; the device does not require physical contact to the current carrying conductor; the device for measuring the magnetic field can support the measurement of high-frequency bandwidth and is compatible with the measurement of direct current and alternating current.

Drawings

The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

Fig. 1 is a block diagram of an apparatus for non-invasively measuring current and voltage in example 1.

Fig. 2 is a circuit diagram of the connection of the apparatus for non-invasive measurement of current and voltage in example 1.

Fig. 3 is a structural diagram of an apparatus for non-invasively measuring current and voltage in example 2.

FIG. 4 is a diagram of second order gradient of magnetic field strength in a non-invasive current and voltage metering device of the present invention.

FIG. 5 is a graph of magnetic induction distribution measurements for a non-invasive current and voltage measuring device according to the present invention.

FIG. 6 is a voltage measurement schematic of a non-invasive current and voltage metering device of the present invention.

Detailed Description

The following examples are presented to enable one of ordinary skill in the art to more fully understand the present invention and are not intended to limit the scope of the embodiments described herein.