The non-standard square coil of magnetic field immunity experiment and calibration steps and calibration systemTechnical field
The present invention relates to EMC test technical field, when particularly High-Voltage Electrical Appliances are tested, the non-standard square coil of magnetic field immunity experiment and calibration steps and calibration system.
Background technology
Magnetic field immunity experiment is one of main contents of High-Voltage Electrical Appliances (especially intelligent high-pressure equipment) EMC test project, and EMC test has been included national compulsory authentication category in.Magnetic field generator (comprising power frequency magnetic field generator, pulsed magnetic generator and damped oscillation magnetic field generator) is the main standard device of implementing magnetic field immunity experiment, the coil of this standard configuration is all that the length of side is the square coil of a meter both at home and abroad at present, is called standard coil.In standard coil efficiency test region for long * wide * high≤0.6 meter * 0.6 meter * 0.5 meter, that but the High-Voltage Electrical Appliances physical dimension that comprises high-tension switch gear and electronic mutual inductor etc. is generally is long * wide * high=and 1.8 meters * 1.8 meters * 2.0 meters, therefore standard coil cannot carry out magnetic field immunity experiment to High-Voltage Electrical Appliances by " immersed method ", and " the type approval test method of the immersed method ”Shi world and the unique approval of national standard.
This just need to manufacture and design the off-gauge large-scale square coil that is applicable to High-Voltage Electrical Appliances, and coil is calibrated, then designs or select the current feedback circuit of coupling, and combination is met the magnetic field immunity to interference system of High-Voltage Electrical Appliances special requirement.But in prior art, the calibration steps to non-standard square coil not, especially calibration steps and the calibration system to two important parameters in the even territory of the coil factor except maximum feed-in electric current and magnetic field, cannot guarantee the accuracy of the calibration of non-coil, also make follow-up test accuracy greatly reduce, even cannot carry out, so in prior art, not adopt non-standard square coil, by " immersed method ", High-Voltage Electrical Appliances are carried out to magnetic field immunity experiment.
Summary of the invention
The object of the present invention is to provide the non-standard square coil of a kind of magnetic field immunity experiment, can meet alignment requirements and operation requirements that High-Voltage Electrical Appliances are realized " immersed method ", calibration steps and calibration system that it is calibrated are also provided simultaneously.
The present invention is achieved through the following technical solutions:
The calibration system of the non-standard square coil of magnetic field provided by the invention immunity experiment, comprises generation loop, magnetic field, and current monitoring loop and/or magnetic field detection loop; Described generation loop, magnetic field comprises current feedback circuit, and for being connected in series the connecting line of current feedback circuit and non-standard square coil; Described current monitoring loop comprises the current probe being arranged on current feedback circuit outgoing side output terminal connecting line, and the oscillograph that is connected with current probe output terminal of input end; Described magnetic field detection loop comprises the magnet field probe being arranged in the field region that non-standard square coil forms, and the magnetic field receiving trap that is connected with magnet field probe output terminal of input end.
Preferably, also comprise computing machine and be arranged on the self-checking device in computing machine; Computing machine is connected with the calibration device that comprises current feedback circuit and oscillograph and/or magnetic field receiving trap by programmed bus respectively.
Further, described self-checking device comprises the input media for setting program and calibration parameter, for selecting to calibrate the program matching device of flow process, for controlling the presetting apparatus of calibration device, for reading the data fetch device of calibration device raw data, for the data processing equipment that raw data carried out to computing and carried out accordance contrast with calibration parameter according to program setting, for the calibration output unit that raw data and comparing result are exported.
The calibration steps of the non-standard square coil of magnetic field provided by the invention immunity experiment, the calibration system based on described in any one scheme in above technical scheme, comprises the steps,
Calibration steps to the coil factor of non-standard square coil; Selection comprises the calibration system in generation loop, magnetic field and current monitoring loop and magnetic field detection loop, by generation loop, magnetic field to non-standard square coil feed-in electric current and produce magnetic field,oscillograph 7 in current monitoring loop obtains the electric current I on non-standard square coil, magneticfield receiving trap 9 in magnetic field detection loop obtains the magnetic field intensity H in non-standard square coil, obtains the coil factor CF of non-standard square coil according to formula CF=H/I;
Calibration steps to the even territory, magnetic field of non-standard square coil;
Calibration steps to the maximum feed-in electric current of non-standard square coil.
Preferably, calibration steps to the coil factor of non-standard square coil, the current feedback circuit input power current in generation loop, magnetic field is calibrated respectively under a plurality of magnetic field intensity grades, under each magnetic field intensity grade, get a plurality of calibration values, average and obtain the calibration value of coil factor.
Further, magnetic field intensity grade comprises 10A/m, 30A/m, 100A/m, 300A/m and five grades of 1000A/m, at least 10 calibration values of calibration under each magnetic field intensity grade.
Further, calibration steps to the even territory, magnetic field of non-standard square coil comprises, electric current under non-standard square coil difference feed-in different magnetic field strength grade, take non-standard square coil plane geometry center is reference point, determine the field region of non-standard be no more than ± 3dB of square coil internal magnetic field intensity, choose the calibration point in field region, each calibration point is averaged after repeatedly calibrating as the magnetic field intensity of this point, obtains the calibration value in even territory, magnetic field by contrast between calibration point magnetic field intensity.
Further again, calibration point comprises non-standard square coil plane geometry central point, and the calibration point in even territory, at least 12 non-standard square coil magnetic field, at least 10 values of each calibration point calibration.
Preferably, the calibration steps of the maximum feed-in electric current of non-standard square coil is comprised, power current effective value when calibration produces 1000A/m power frequency magnetic field, and/or calibrate the pulse current value while producing 1000A/m pulsed magnetic field.
The non-standard square coil of magnetic field provided by the invention immunity experiment, adopts copper core cable, and the length of side is 3 meters, and the number of turn is 3 circles, qualified by the calibration steps calibration described in above any one technical scheme.
Compared with prior art, the present invention has following useful technique effect:
Calibration system of the present invention has realized the calibration of non-standard square coil key parameter and evaluation by setting and the combination of different circuit, especially can objectively react the even territory of non-standard square coil coil factor and magnetic field, fill up the blank of industry, for the calibration of non-standard square coil provides, detected basis.
Further, by the self-checking device being connected with calibration device respectively in computing machine, realization is to the input of program, selection and control, and automatically completing the collection of data, processing and output, avoided the stochastic error that also repeatedly regulates calibration device to introduce because of hand computation, improve work efficiency, simplified process of the test and operation, guaranteed calibrating quality.
Calibration steps of the present invention, by the calibration to coil factor, even territory, magnetic field and maximum feed-in electric current respectively, thereby whether the non-standard square coil of objective appraisal can be used in the immunity experiment in High-Voltage Electrical Appliances magnetic field comprehensively, avoided the deviation of bringing after only calibrating by maximum feed-in electric current.
Further, the calibration steps by averaging after repeatedly calibrating under different magnetic field strength grade, can reduce the impact of test error on result, obtains more accurately the calibration value of coil factor; And utilize the division of concrete scope, guaranteed the comprehensive coverage of test, and rational data operation quantity, when guaranteeing precision, guaranteed test efficiency.
Further, according to the requirement of test standard, determine the calibration steps in even territory, magnetic field, with the field region of ± 3dB, be limited, by multiple spot, calibrated the step being averaged respectively, realized the accurate calibration to even territory, magnetic field.And utilize the division of concrete scope and the selection of calibration point, make can reflect by the calibration of limited calibration point the calibration situation in the even territory of global magnetic field.
Further, power current effective value while needing calibration to produce 1000A/m magnetic field by test standard requirement, pulse current value during 1000A/m pulsed magnetic field, has also just met the latter as long as meet the former, therefore can only to the former, calibrate, dirigibility and the adaptability of test are large.
The non-standard square coil of the present invention, the fan-out capability of the current feedback circuit being mated requires low, and coil weight is light, and current-carrying is stable, and with low cost, processing and fabricating is simple.
Accompanying drawing explanation
Fig. 1 is the structure connection layout of the maximum feed-in electric current of embodiment of the present invention alignment system calibration.
Fig. 2 is the structure connection layout of embodiment of the present invention alignment system calibration coil factor calibration.
Fig. 3 is the structure connection layout of embodiment of the present invention alignment system calibration magnetic field even territory calibration; Wherein a is calibration wiring diagram, and b is calibration point distribution plan.
Fig. 4 is the structure connection layout of the maximum feed-in electric current of embodiment of the present invention alignment system automatic calibration.
Fig. 5 is the structure connection layout in embodiment of the present invention alignment system automatic calibration coil factor and/or even territory, magnetic field.
Fig. 6 is the structural representation of non-standard square coil in the embodiment of the present invention.
In figure: 1 is computing machine, 2 is non-standard square coil, and 3 is self-checking device, and 4 is current feedback circuit, 5 is current probe, and 6 is connecting line, and 7 is oscillograph, and 8 is magnet field probe, 9 is magnetic field receiving trap, and 10 is frontier point, point centered by 11, and 12 is programmed bus.
Embodiment
Below in conjunction with specific embodiment, the present invention is described in further detail, and the explanation of the invention is not limited.
The calibration system of the non-standard square coil of magnetic field of the present invention immunity experiment, comprises generation loop, magnetic field, and current monitoring loop and/or magnetic field detection loop; Described generation loop, magnetic field comprisescurrent feedback circuit 4, and for being connected in series the connectingline 6 ofcurrent feedback circuit 4 andnon-standard square coil 2; Described current monitoring loop comprises thecurrent probe 5 being arranged oncurrent feedback circuit 4 outgoing side outputterminal connecting lines 6, and theoscillograph 7 that is connected withcurrent probe 5 output terminals of input end; Described magnetic field detection loop comprises themagnet field probe 8 being arranged in the field region that non-standardsquare coil 2 forms, and the magneticfield receiving trap 9 that is connected withmagnet field probe 8 output terminals of input end.Wherein, connecting line preferably adopts twisted-pair feeder or the concentric cable that is no more than 3 meters.
In this preferred embodiment, in order to realize automatic calibration, also comprisecomputing machine 1 and be arranged on the self-checkingdevice 3 incomputing machine 1;Computing machine 1 is connected with the calibration device that comprisescurrent feedback circuit 4 andoscillograph 7 and/or magneticfield receiving trap 9 by programmedbus 12 respectively.Wherein, self-checking device 3 comprises for setting the input media of calibration process program and calibration parameter, for selecting to calibrate the program matching device of flow process, for controlling the presetting apparatus of calibration device, for reading the data fetch device of calibration device raw data, for the data processing equipment that raw data is carried out to computing and carried out accordance contrast with calibration parameter according to calibration flow process program setting, for the calibration output unit that raw data and comparing result are exported.
Wherein, by input media, the needed various parameters of calibration can be set, comprise the standard of power current generator parameter, oscillograph parameter, calibrating element parameter (as current probe, magnet field probe etc.), calibration institute foundation etc.
Pass through presetting apparatus, can realize the programmed control to calibration device, and can the compatible same quasi-instrument of main flow both at home and abroad, comprise that control bus storehouse (compatible bus has RS-232, GPIB, USB and LAN etc.), oscillograph Driver Library (polytype oscillograph such as compatible Agilent, Tektronics and Lecroy), power current generator Driver Library products such as () compatible Switzerland TESEQ, Switzerland EM TEST, distant places, Ling Shi, Hangzhou, Shanghai, instrument exchange and control (adopting IVI-COM software engineering to realize the exchange of above-mentioned instrument); And the control to programmable instrument.
By program matching device, realization is to the selection of calibration process correlated activation and configuration, comprise that (selection adopts the calibration circuit shown in Fig. 4 or Fig. 5 to calibration line configuring, and dispose related parameter), the configuration (startup calibration process, completes calibration activities) of calibration flow process configuration (as current class or magnetic field grade and the calibration sequence of needs calibration) and calibration process.
By data fetch device, data processing equipment and calibration output unit, realization is processed according to calibration process program the data that obtain in calibration process, to the magnet field probe extracting and oscillograph data, according to related standards, carry out accordance comparison, finally formation meets raw readings or the form of specific format requirement and exports.
The calibration steps of the non-standard square coil of magnetic field of the present invention immunity experiment, the calibration system based on described in above preferred embodiment describes, comprises the steps,
Calibration steps to the coil factor of non-standard square coil; Selection comprises the calibration system in generation loop, magnetic field and current monitoring loop and magnetic field detection loop, by generation loop, magnetic field to non-standard square coil feed-in electric current and produce magnetic field,oscillograph 7 in current monitoring loop obtains the electric current I on non-standard square coil, magneticfield receiving trap 9 in magnetic field detection loop obtains the magnetic field intensity H in non-standard square coil, obtains the coil factor CF of non-standard square coil according to formula CF=H/I; Wherein, the m of coil factor unit-1, the A/m of magnetic field intensity unit, chemic A.Calibration steps to the even territory, magnetic field of non-standard square coil.Calibration steps to the maximum feed-in electric current of non-standard square coil.
Wherein, calibration steps to the coil factor of non-standard square coil, thecurrent feedback circuit 4 input power currents in generation loop, magnetic field are calibrated respectively under a plurality of magnetic field intensity grades, under each magnetic field intensity grade, get a plurality of calibration values, average and obtain the calibration value of coil factor.Magnetic field intensity grade comprises 10A/m, 30A/m, 100A/m, 300A/m and five grades of 1000A/m, at least 10 calibration values of calibration under each magnetic field intensity grade.
Calibration steps to the even territory, magnetic field of non-standard square coil comprises, electric current under non-standard square coil difference feed-in different magnetic field strength grade, take non-standard square coil plane geometry center is reference point, determine the field region of non-standard be no more than ± 3dB of square coil internal magnetic field intensity, choose the calibration point in field region, each calibration point is averaged after repeatedly calibrating as the magnetic field intensity of this point, obtains the calibration value in even territory, magnetic field by contrast between calibration point magnetic field intensity.As figure calibration point comprises non-standard square coil plane geometry central point, and the calibration point in even territory, at least 12 non-standard square coil magnetic field, at least 10 values of each calibration point calibration.
Calibration steps to the maximum feed-in electric current of non-standard square coil comprises, power current effective value when calibration produces 1000A/m power frequency magnetic field, and/or calibrate the pulse current value while producing 1000A/m pulsed magnetic field.
Concrete, as shown in Figure 1, to maximum feed-in correcting current, configuration generation loop, magnetic field and current monitoring loop, the current class ofcurrent feedback circuit 4 is set, fromoscillograph 7, read the voltage parameter monitoring, be multiplied by the no-load voltage ratio ofcurrent probe 5, obtain the maximum feed-in electric current in actualnon-standard square coil 2.
As shown in Figure 2, to the calibration of coil factor, configuration generation loop, magnetic field and current monitoring loop and magnetic field detection loop, draw field strength values H by magneticfield receiving trap 9, byoscillograph 7 read current I, according to formula CF=H/I, obtain the coil factor CF of non-standard square coil.Current feedback circuit 4 input power currents in generation loop, magnetic field, a plurality of magnetic field intensity grades under calibrate respectively, comprising 10 calibration values under 10A/m, 30A/m, 100A/m, 300A/m and five magnetic field intensity grades of 1000A/m, average and obtain the calibration value of coil factor.
As shown in Figure 3 a, to magnetic field even territory calibration, configuration generation loop, magnetic field and magnetic field detection loop, current monitoring loop as required selectivity configures, and obtains the field strength values of each calibration point by magneticfield receiving trap 9; As shown in Figure 3 b, whenmagnet field probe 8 is arranged, except central point as areference point 11, also need to detect 12 calibration points in even territory, magnetic field, this preferred embodiment take A-L totally 12 frontier points that are positioned at even territory, magnetic field calibrate as example, shown in figure for a cubical summit in non-standard square coil be positioned at the sideline mid point of coil plane, each calibration point duplicatedetection 10 times, and using mean value as the magnetic field intensity of this point, do homogeneity judgement.
The non-standard square coil of magnetic field of the present invention immunity experiment, adopts copper core cable, and the length of side is 3 meters, and the number of turn is 3 circles, qualified by above-described calibration steps calibration.
Wherein, grow * wide * height of maximum physical dimension according to High-Voltage Electrical Appliances magnetic field immunity to interference test product=1.8 meters * 1.8 meters * 2.0 meters, again according to the characteristic distributions of coil internal magnetic field, meeting under the condition of 3dB principle, the non-standard square coil length of side is 3 meters, single turn square coil for 3 meters of length of sides, according to Distribution of Magnetic Field theory, calculate, its CF is about 0.3, as produce 1000A/m power frequency magnetic field or the 1000A/m pulsed magnetic field of standard code, need the power current of about 3400Arms or the pulse current of 3400A, this fan-out capability tocurrent feedback circuit 4 requires very high, nor be beneficial to the cost of controllingcurrent feedback circuit 4, therefore adopt multiturn coil to reduce the output power of generator, for balancing coil weight and the requirement of generator output current, be designed to three circles.According to getting optimal value under the restriction of current-carrying and weight, calculate, select the copper core cable of 70mm2.