CN2385339Y - Magnetic balancing current sensor for current measuring sampling - Google Patents

Abstract

The utility model discloses a magnetic balancing current sensor which is used for current measuring sampling without a contact for cables; the technical proposal comprises a shell and a core and a circuit board in the inner part, wherein, the shell is oppositely connected with an inverse concave-shaped upper box and a concave-shaped lower box. The magnetic balancing current sensor can be arbitrarily detached and butt while assembling on the spot, which does not affect the running of the original equipment. The electronic circuit increases the interference immunity by the adoption of two paralleled hall-elements of an H [1] and an H [2]. The operational amplifier circuit causes the measuring accuracy to be raised to 0.1 stage from the original grade of 0.5 by the adoption of the model with high accuracy and low drift, particularly an LF353 model.

Description

The magnetic balance type current sensor of current measurement sampling usefulness

The utility model relates to the measurement mechanism of electric current, the magnetic balance type current sensor of the sampling of current measurement specifically usefulness.

The designer discloses a kind of technical scheme of current sensor of current measurement sampling usefulness in the patent document of ZL962213225, this current sensor highly sensitive, there is not the dead band, tested cable is isolated fully with output, wiring is fairly simple during use, very popular with users, product squeezes into the international market at present.Yet finding to also have not enough place in implementation process, mainly is " returning " font structure that adopts one, inconvenience dismounting during use, and the anti-interference of electronic circuit and measuring accuracy also have the possibility of raising.

The purpose of this utility model is that a kind of middle dismounting easy to use of design, anti-interference are stronger, the magnetic balance type current sensor of the current measurement sampling usefulness that measuring accuracy is higher.

The purpose of this utility model makes " returning " font structure of disome butt joint, inner electronic circuit into and does also that suitable improvement realizes by one " being returned " the font structure, and specifically technical scheme is as follows: the utility model still is made up of shell, magnetic core and wiring board three parts.Its middle shell is formed by last box and the butt joint of following box, wherein go up box by " recessed " font side plate and base plate are formed, following box is made up of " recessed " font side plate and base plate, last box and following box are " returning " font housing by the removable butt joint of interfacing part, fixture is arranged on the housing, in the last box and in the following box " C " font magnetic core of laying by the shape of box is arranged respectively, wherein go up on the magnetic core in the box and be wound with telefault, between the magnetic core in last box epipleural and last box wiring board is arranged, upper corner at last box is equipped with connection terminal, this connection terminal has 4 binding posts, i.e. signal output part M, just, negative power end V+ and V-, and earth terminal.Two identical Hall element H that are connected in parallel to each other are arranged in the wiring board ₁And H ₂, these two Hall elements lay respectively at two inferior horn places in the box, and resistance R is passed through at the angle 1 of two Hall elements ₁Meet positive source V+, resistance R is passed through at angle 4 ₂Meet power cathode V-, resistance R is passed through at the angle 2 and the angle 3 of Hall element respectively ₃And R ₄Connect positive input terminal and the negative input end of high precision, low DRIFT TYPE discharge circuit Ic, the positive and negative power input of discharge circuit Ic meets positive and negative power supply V+ and V-respectively, and the output terminal of discharge circuit Ic passes through resistance R ₅Meet two identical triode Q respectively ₁And Q ₂Base stage, two triode Q ₁And Q ₂Collector connect the head end that power supply V+ and V-, two emitters link each other and connect inductance L respectively, the tail end of inductance L meets connection terminal output terminal M, the head end of inductance L meets diode D simultaneously ₁Positive pole and ID ₂Negative pole, diode D ₁Negative pole meet power supply V+, diode D ₂Positive pole meet power supply V-, be in series with capacitor C and resistance R between the negative input end of discharge circuit and the inductance L head end ₆The utility model adopts the epoxy resin embedding to need not loam cake.

A cable with supply line during use passes in the square opening of the utility model centre, when having electric current to pass through in the cable cable around produce magnetic field, the electrorheological magnetizing field also changes, and magnetic core disperses magnetic field concentration with around the cable, is Hall element H by magnetic-sensitive elements again ₁And H ₂Magnetic signal is transformed into electric signal, becomes the electric signal that to measure, so the utility model is specialized in current measurement time sampling usefulness through amplification.

The utility model does not influence the normal operation of field apparatus and circuit owing to be to be formed by the interfacing part butt joint by last box and following box during dismounting.Owing to adopt two Hall elements in parallel, antijamming capability strengthens, owing to adopt the discharge circuit Ic of high precision, low drift, measuring accuracy improves.

The designer has made an embodiment, below embodiment is described:

Fig. 1 is embodiment front view (epoxy resin of embedding removes under the situation in the box)

Fig. 2 is the vertical view of embodiment

Fig. 3 is the electronic-circuit diagram of embodiment

By Fig. 1 and Fig. 2 as seen, present embodiment is by shell, magnetic core is formed to become with wiring board (2), shell is formed by last box (1) and following box (12) butt joint, wherein go up box by " recessed " font side plate (5) and base plate are formed, following box is made up of " recessed " font side plate (11) and base plate, last box and following box are " returning " font housing by the removable butt joint of interfacing part, interfacing part be positioned at box root edge both sides and following box upper limb both sides on, down to lug (7) and (8), with to the lug attachment screw, nut, the both sides of following box bottom side plate are protruding fixed-wing (9), the center section of following box epipleural is extended with fixed head (6) backward, porose on fixed-wing and the fixed head, on, " C " font magnetic core (4) and (10) of laying by the shape of box are arranged respectively in the following box, the magnetic core of wherein going up in the box (4) is wound with telefault (3), between the inside surface of last box epipleural and magnetic core, wiring board (2) is arranged, upper corner has a connection terminal (13) in back, last box left side, this connection terminal has four wiring to lean on, be signal output part M, just, negative supply V+ and V-, and earth terminal, two identical Hall element H that are connected in parallel to each other are arranged in the wiring board ₁And H ₂, these two Hall elements lay respectively at two inferior horn places in the box.

As seen from Figure 3, the electronic circuit of present embodiment comprises power circuit, magnetic field detection circuit, signal amplification circuit, output circuit, adjustment and feedback circuit, and wherein power circuit is made up of the external power supply of ± 12-24 volt; The magnetic field detection circuit comprises Hall element H ₁And H ₂, resistance R ₁And R ₂Signal amplification circuit comprises discharge circuit Ic and resistance R ₃, R ₄Output circuit comprises triode Q ₁, Q ₂And resistance R ₅Adjustment and feedback circuit comprise diode D ₁And D ₂, resistance R ₆, capacitor C and inductance L.The connection method of each components and parts is with described in the previous technique scheme.Use the epoxy resin embedding in the box.

Present embodiment shell sizes (not comprising interfacing part and fixture) length * wide * height=124 * 26 * 70mm, Hall element is selected the THS126 type, coefficient to Hall element, be to screen consistent with enlargement factor zero point, discharge circuit Ic selects the LF353 type of high precision, low drift, and magnetic core selects soft magnetic material to plate not alloy or high-quality silicon steel sheet is made, admittedly be this material initial magnetic permeability height, magnetization curve is more straight, and magnetic saturation intensity is higher.Present embodiment interference free performance height, measuring accuracy is brought up to 0.1 grade by original 0.5 grade.

Claims (2)

1, the magnetic balance type current sensor of current measurement sampling usefulness is made up of shell, magnetic core and wiring board, and fixture is arranged on the housing, it is characterized in that housing is formed by last box and the butt joint of following box, wherein goes up box by " recessed " font side plate and base plate are formed.Following box is made up of " recessed " font side plate and base plate, last box and following box are " returning " font housing by the removable butt joint of interfacing part, magnetic core has two, be all " C " font, shape by box is placed in the upper and lower box respectively, wherein go up on the magnetic core in the box and be wound with telefault, between the magnetic core of wiring board in last box epipleural and last box, upper corner at last box is equipped with connection terminal, this connection terminal has 4 binding posts, be signal output part M, positive and negative power end V+ and V-and earth terminal, two identical Hall element H that are connected in parallel to each other are arranged in the wiring board ₁And H ₂, these two Hall elements lay respectively at two inferior horn places in the box, two Hall element H ₁And H ₂Angle 1 pass through resistance R ₁Meet positive source V+, resistance R is passed through at angle 4 ₂Meet power cathode V-, resistance R is passed through at the angle 2 and the angle 3 of Hall element respectively ₃And R ₄Connect positive input terminal and the negative input end of discharge circuit Ic, the positive and negative power input of discharge circuit Ic meets positive and negative power supply V+ and V-respectively, and the output terminal of discharge circuit Ic passes through resistance R ₅Meet two identical triode Q respectively ₁And Q ₂Base stage, two triode Q ₁And Q ₂Collector connect the head end that power supply V+ and V-, two emitters link each other and connect inductance L respectively, the tail end of inductance L meets connection terminal output terminal M, the head end of inductance L meets diode D simultaneously ₁Positive pole and D ₂Negative pole, diode D ₁Negative pole meet power supply V+, diode D ₂Positive pole meet power supply V-, be in series with capacitor C and resistance R between the negative input end of discharge circuit Ic and the inductance L head end ₆, unit, the device epoxy resin embedding in the upper and lower box.

2, the magnetic balance type current sensor of current measurement according to claim 1 sampling usefulness is characterized in that the Hall element H of two parallel connections ₁, H ₂Select the THS126 type, discharge circuit Ic selects the LF353 type.