Summary of the invention
The technical problem to be solved in the present invention is to provide a kind of current measuring devices that high-precision is easy to install, by based on non-
The temperature of the thermosensitive resistance measurement conducting wire of balanced bridge learns the variation feelings of conductive line resistance values by the situation of change for the temperature surveyed
Condition is affected by temperature by concatenating a controllable resistor module before former integrating circuit by controlling its resistance value come compensating wire
Generated error.
The technical solution adopted by the present invention is that:A kind of current measuring device that high-precision is easy to install, including Rogowski coil mould
Block, temperature-measuring module, data processing module, display module, communication module, controllable resistor module, communication module, display mould
Block, controllable resistor module, Rogowski coil module and temperature-measuring module are connected with data processing module, Rogowski coil module
Including Rogowski coil and integrating circuit, temperature-measuring module is used to measure the temperature of Rogowski coil, and controllable resistor module includes can
Resistance and fixed value resistance, fixed value resistance one end is adjusted to connect with Rogowski coil, one end connection of the other end and adjustable resistance, adjustable electric
The other end of resistance is connect with integrating circuit, and temperature-measuring module uses nonequilibrium bridge structure bridge circuit, communication module and outer
Portion's device talk.
Specifically, the bridge circuit of the temperature-measuring module includes fixed value resistance R1、R2、R3With thermistor RX, fixed
It is worth resistance R1、R2One termination power cathode, fixed value resistance R1Another termination fixed value resistance R3One end, fixed value resistance R2It is another
One termination thermistor RXOne end, fixed value resistance R3The other end, thermistor RXAnother termination positive pole, temperature-sensitive electricity
Hinder RXIt is embedded in Rogowski coil, fixed value resistance R1、R3Connection midpoint and fixed value resistance R2With thermistor RXConnection midpoint it
Between voltage be U0。
Specifically, the Rogowski coil be open architecture, including coil body 1, non-magnetic material skeleton 2, shaft 3,
Insulating layer 4, lock 5, non-magnetic material skeleton 2 are two semicircular rings, coil body 1 uniformly around on non-magnetic material skeleton 2,
Insulating layer 4 is wrapped up outside coil body 1,2 one end of non-magnetic material skeleton of two semicircular rings passes through 5 connection of lock, the other end
It is rotatablely connected by shaft 3, lock 5 is fixed on insulating layer 4.
Specifically, resistance of the display module for the temperature data, adjustable resistance of the acquisition of displays temperature measurement module
Value.
Preferably, the data processing module includes single-chip microcontroller, fpga chip, SRAM, EPCS, and SRAM is used
CY7C006A, fpga chip use Spartan-6FPGA device.
The beneficial effects of the present invention are:The device acquires the voltage and Roche of coil temperature-measuring module simultaneously
The voltage of coil module concatenates an adjustable resistance in the integration circuit and is affected by temperature generated error to the resistance of coil
It compensates.
Embodiment 1:As shown in Figs 1-4, a kind of current measuring device that high-precision is easy to install, including Rogowski coil module,
Temperature-measuring module, data processing module, display module, communication module, controllable resistor module, communication module, display module, can
Control resistive module, Rogowski coil module and temperature-measuring module are connected with data processing module, and Rogowski coil module includes
Rogowski coil and integrating circuit, temperature-measuring module are used to measure the temperature of Rogowski coil, and controllable resistor module includes adjustable electric
Resistance and fixed value resistance, fixed value resistance one end are connect with Rogowski coil, one end connection of the other end and adjustable resistance, adjustable resistance
The other end is connect with integrating circuit, and temperature-measuring module uses nonequilibrium bridge structure bridge circuit, and communication module is set with outside
Standby communication.For Rogowski coil module for acquiring current signal, temperature-measuring module is used to measure the temperature of Rogowski coil, at data
Module is managed to be used to the resistance value of adjustable resistance is adjusted, to Roche according to Rogowski coil module, the acquisition data of temperature-measuring module
Coil, which is affected by temperature, to be compensated.
Further, as shown in figure 3, the bridge circuit of the temperature-measuring module includes fixed value resistance R1、R2、R3With
Thermistor RX, fixed value resistance R1、R2One termination power cathode, fixed value resistance R1Another termination fixed value resistance R3One end,
Fixed value resistance R2Another termination thermistor RXOne end, fixed value resistance R3The other end, thermistor RXAnother termination electricity
Source anode, thermistor RXIt is embedded in Rogowski coil, fixed value resistance R1、R3Connection midpoint and fixed value resistance R2With thermistor RX
Connection midpoint between voltage be U0。
By thermistor RXIt is embedded in Rogowski coil, it is possible to accurately know temperature when Rogowski coil work,
Due to having between the resistance value and temperature of Rogowski coil conducting wire there are certain functional relation, its resistance can be calculated according to its temperature
Value, can carry out temperature-compensating to Rogowski coil according to the resistance value keeps final measurement more acurrate.
Further, as shown in Figure 2,4, the Rogowski coil is open architecture, including coil body 1, non magnetic material
Expect that skeleton 2, shaft 3, insulating layer 4, lock 5, non-magnetic material skeleton 2 are two semicircular rings, coil body 1 is uniformly around non-magnetic
Property material skeleton 2 on, insulating layer 4 is wrapped up outside coil body 1,2 one end of non-magnetic material skeleton of two semicircular rings passes through lock
5 connection of button, the other end are rotatablely connected by shaft 3, and lock 5 is fixed on insulating layer 4.Since Rogowski coil is open architecture,
It is easily installed.
Further, temperature data, adjustable resistance of the display module for the acquisition of displays temperature measurement module
Resistance value.
Further, the data processing module includes single-chip microcontroller, fpga chip, SRAM, EPCS, and the SRAM is
CY7C006A is the high speed twoport static state RAM of 16kb × 8 of Cypress company production, and access speed is less than 20ns.The device has
Real dual-port, can carry out data access simultaneously, and two ports have independent control signal wire, address wire and data
Line expands memory capacity and data width with can be convenient additionally by master/slave selection.Dual port RAM can be used for improving handling up for RAM
Rate is suitable for making in real-time data buffer storage.EPCS can not lose data in the case where power down.
Further, the FPGA is the Spartan-6FPGA device of Xilinx company, passes through Verilog HDL language
Speech is written and read control to dual port RAM.
The disposed of in its entirety process of data processing module is:Rogowski coil module output signal is the differential of Current versus time.
The circuit that the voltage signal of output is integrated by one, so that it may really restore input current.In order to compensate for temperature
It influences, with a fixed value resistance and an adjustable resistance series connection before integrating circuit, the resistance value of adjustable resistance is by Rogowski coil
The resistance value of conducting wire determines.
Due to having between the resistance value and temperature of Rogowski coil conducting wire there are certain functional relation, by being led to Rogowski coil
Line measures the resistance value of conducting wire at different temperatures, and obtained data are gone out between resistance and temperature by least square fitting
Equation.Further, the resistance value of conducting wire can be calculated by measuring the temperature of Rogowski coil conducting wire.There are R=f (T), Δ R
=R0- R, wherein R0, R is that temperature is t respectively0With the resistance value of conducting wire when t, Δ R is to need the resistance value compensated (by temperature shadow
Ring the error generated), the value of Δ R is transferred to single-chip microcontroller, by single-chip microcontroller controlling potential device to the adjustable control of resistance.
Fig. 3 is the schematic diagram of nonequilibrium bridge, when nonequilibrium bridge works, keeps R1、R2、R3For fixed value resistance, work as temperature
Variation causes thermistor RXOutput voltage U when variation0With variation.E is fixed value voltage,
The temperature characterisitic of thermistor is:In formula, A is constant related with material properties and resistor geometry, B
For constant related with material semiconductor property, T is absolute temperature, due to U0With RXBetween there are certain functional relations, it is known that
U0Situation of change it is known that RXSituation of change, and then be known that temperature situation of change.Measurement temperature it
Before, first to obtain the temperature characterisitic of thermistor.To obtain accurate resistivity measurements, can be measured not with wheatstone bridge
Thermosensitive resistance under synthermal.In a certain range, the relationship for measuring output voltage and temperature, using least square fitting
U0- t relationship.
The working principle of the invention is:Rogowski coil module is for acquiring current signal, and temperature-measuring module is for measuring
The temperature of Rogowski coil, data processing module are fitted for handling the data of coil module and temperature-measuring module
Functional relation between Rogowski coil conducting wire and Rogowski coil temperature, and a resistance value is obtained, pass through monolithic further according to the resistance value
Machine, which controls controllable resistor module and adjusts the resistance value of adjustable resistance, carries out temperature-compensating, and display module shows coil temperature, non-equilibrium
The waveform etc. that the output voltage of electric bridge, the resistance value of adjustable resistance and acquired data are drawn, naturally it is also possible to expand other letters
Breath, communication module are made of the transmission for final data ethernet module and USB module.
The foregoing is merely the preferable embodiments of the present invention, are not intended to limit the present invention in any form, all
Simple modification, same variation are made to the above case study on implementation according to the technical essence of the invention, each fall within protection scope of the present invention
Within.