CN205920215U - Current transformer harmonic error measurement system - Google Patents

Abstract

The utility model discloses a current transformer harmonic error measurement system, this system is including the harmonic heavy current generating device who is used for generating the harmonic heavy current, be used for measuring the harmonic heavy current, obtain standard signal's standard current transformer, be used for measuring the harmonic heavy current, what obtain the measured signal is surveyed current transformer, a harmonic current measuring device for inciting somebody to action standard signal with is surveyed signal conversion and is become to treat that signal processing erupts simultaneously delivers to the host computer, a host computer that is used for according to treating that signal processing obtains the fundamental wave until content, ratio and the angular difference of N subharmonic. Clearly, the utility model provides an error of current transformer when measuring can be known to the harmonic to current transformer harmonic error measurement system, and then obtains the influence of harmonic error ( ratio difference, angular difference) between to the standard signal of the measured signal of being surveyed current transformer output and the output of standard current transformer, and be convenient follow -up to being improved by survey current transformer and to the accurate measurement of harmonic.

Description

A kind of current transformer harmonic error measuring system

Technical field

This utility model is related to current transformer error field of measuring technique, more particularly to a kind of current transformer harmonic wave Error measuring system.

Background technology

With the increasing of nonlinear load in electrical network, harmonic pollution is increasingly serious, particularly with electric traction system as generation In the electric power system of table, because electric locomotive is on a large scale using produced harmonic wave, result in the evil of the system side quality of power supply Change, compromise the safety of system stable operation, the problems referred to above cause the concern to power quality problem for the power industry, and it is right to realize The accurate metering of the accurate measurement harmony wave power of harmonic wave is significant.Correlational study of the prior art pays attention to harmonic distortion The accuracy of lower electric energy meter metering and the improvement of metering method, and often have ignored harmonic wave in electric power meter with electric energy meter The impact that the current transformer using cooperatively is brought, in addition, also cannot know harmonic wave to current transformer by mistake in prior art The impact that difference band comes.

Therefore, a kind of current transformer harmonic error measuring system solving above-mentioned technical problem how is provided to be this area The current technical issues that need to address of technical staff.

Utility model content

The purpose of this utility model is to provide a kind of current transformer harmonic error measuring system, and this system can know electricity Error when to harmonic measure for the current transformer, and then obtain measured signal and the standard that harmonic wave exports to tested current transformer The impact of error (ratio difference, angular difference) between the standard signal of current transformer output, conveniently subsequently to tested current transformer Improve and the accurate measurement to harmonic wave.

For solving above-mentioned technical problem, this utility model provides a kind of current transformer harmonic error measuring system, bag Include:

For receiving and according to user input to the fundamental wave of host computer, 3 subharmonic, 5 subharmonic until the parameter of nth harmonic Generate the harmonic wave high-current generation device of harmonic wave high current, wherein, described parameter includes described fundamental wave until the containing of nth harmonic Amount, amplitude, phase place and frequency, n is the odd number not less than 3；

It is connected with described harmonic wave high-current generation device, is used for described harmonic wave high current is measured, obtain standard letter Number standard current transformer；

It is connected with described harmonic wave high-current generation device, is used for described harmonic wave high current is measured, obtain tested letter Number tested current transformer；

Be connected with described standard current transformer and described tested current transformer respectively, for by described standard signal and Described measured signal is converted into pending signal and sends to the harmonic current measurement device of described host computer；

It is connected with described harmonic wave high-current generation device and described harmonic current measurement device respectively, be used for according to described Pending signal obtains described fundamental wave until the content of nth harmonic, ratio are poor and angular difference, and then obtains described tested current transformer Measure described fundamental wave up to the described host computer of error during nth harmonic.

Preferably, n is the odd number more than 9, and described harmonic wave high-current generation device includes:

Be connected with described host computer, for receiving described host computer according to the fundamental wave of user input, 3 subharmonic, 5 subharmonic Until the parameter of nth harmonic is corresponding respectively generates fundamental wave generation instruction until 7 subharmonic generate instruction and 9-n combined harmonic Generate a fpga of instruction；

Input is connected with a described fpga, for generating, according to described fundamental wave, the fundamental wave work(that instruction generates fundamental signal Rate source；

Input is connected with a described fpga, for generating, according to 3 subharmonic, 3 times that instruction generates 3 rd harmonic signal Harmonic power source；

Input is connected with a described fpga, for generating, according to 5 subharmonic, 5 times that instruction generates 5 rd harmonic signal Harmonic power source；

Input is connected with a described fpga, generates 7 rd harmonic signal for generating instruction according to described 7 subharmonic 7 subharmonic power sources；

Input is connected with a described fpga, generates 9-n time again for generating instruction according to described 9-n combined harmonic Close the combined harmonic power source of harmonic signal；

Respectively with the outfan in described fundamental power source, the outfan of 3 subharmonic power sources, 5 subharmonic power sources defeated Go out end, the outfan of the outfan of 7 subharmonic power sources and combined harmonic power source connects, for by described fundamental signal, 3 The up-flow that rd harmonic signal, 5 rd harmonic signal, 7 rd harmonic signal and 9-n combined harmonic signal are coupled and amplified Device.

Preferably, n is 19.

Preferably, described standard current transformer is the current transformer of 0.05s level.

Preferably, described standard current transformer is high-accuracy current divider.

Preferably, described tested current transformer is 0.2 grade of current transformer.

Preferably, described tested current transformer is electronic current mutual inductor.

Preferably, described harmonic current measurement device includes:

Relay module, ad sampling module, the 2nd fpga, stm32 and the switch being sequentially connected, wherein, described continues Electrical appliance module includes sampling resistor, and described ad sampling module includes adc sampling A/D chip, and described switch is with described host computer even Connect；

Described harmonic current measurement device also includes:

The synchronization module being connected with described 2nd fpga and ft3 module；

The first electrical network mouth, the second electrical network mouth, the first smooth network interface and the second smooth network interface being connected with described switch；

The 3rd smooth network interface being connected with described switch by the 3rd fpga.

This utility model provides a kind of current transformer harmonic error measuring system, and this system is included for generating harmonic wave The harmonic wave high-current generation device of high current；For measuring to harmonic wave high current, the normalized current obtaining standard signal is mutual Sensor；For measuring to harmonic wave high current, obtain the tested current transformer of measured signal；For by standard signal and quilt Survey signal to be converted into pending signal and send to the harmonic current measurement device of host computer；For obtaining according to pending signal Fundamental wave until the content of nth harmonic, than difference and angular difference, and then obtain tested current transformer measurement fundamental wave until during nth harmonic Error host computer.It can be seen that, the application simulates power train by generating the harmonic wave high-current generation device of harmonic wave high current System environment, then record according to the tested current transformer respectively harmonic wave high current being measured and standard current transformer Measured signal and standard signal obtain the content of fundamental wave and nth harmonic, than difference and angular difference, by with standard current transformer Relatively, just would know that error when to harmonic measure for the current transformer, and then obtain harmonic wave and tested current transformer is exported Measured signal and the standard signal of standard current transformer output between error (ratio difference, angular difference) impact, convenient follow-up Tested current transformer is improved and the accurate measurement to harmonic wave.

Brief description

In order to be illustrated more clearly that the technical scheme in this utility model embodiment, below will be to prior art and embodiment In required use accompanying drawing be briefly described it should be apparent that, drawings in the following description are only of the present utility model Some embodiments, for those of ordinary skill in the art, on the premise of not paying creative work, can also be according to this A little accompanying drawings obtain other accompanying drawings.

A kind of structural representation of current transformer harmonic error measuring system that Fig. 1 provides for this utility model；

The structural representation of another kind of current transformer harmonic error measuring system that Fig. 2 provides for this utility model；

The structural representation of another kind of current transformer harmonic error measuring system that Fig. 3 provides for this utility model；

A kind of schematic diagram of harmonic current measurement device that Fig. 4 provides for this utility model.

Specific embodiment

Core of the present utility model is to provide a kind of current transformer harmonic error measuring system, and this system can know electricity Error when to harmonic measure for the current transformer, and then obtain measured signal and the standard that harmonic wave exports to tested current transformer The impact of error (ratio difference, angular difference) between the standard signal of current transformer output, conveniently subsequently to tested current transformer Improve and the accurate measurement to harmonic wave.

Purpose, technical scheme and advantage for making this utility model embodiment are clearer, new below in conjunction with this practicality Accompanying drawing in type embodiment, is clearly and completely described it is clear that being retouched to the technical scheme in this utility model embodiment The embodiment stated is a part of embodiment of this utility model, rather than whole embodiments.Based on the enforcement in this utility model Example, the every other embodiment that those of ordinary skill in the art are obtained under the premise of not making creative work, broadly fall into The scope of this utility model protection.

Refer to Fig. 1, a kind of structure of current transformer harmonic error measuring system that Fig. 1 provides for this utility model is shown It is intended to, this test system includes:

For receiving and according to user input to the fundamental wave of host computer 5,3 subharmonic, 5 subharmonic until the ginseng of nth harmonic Number generates the harmonic wave high-current generation devices 1 of harmonic wave high currents, and wherein, parameter includes fundamental wave until the content of nth harmonic, width Value, phase place and frequency, n is the odd number not less than 3；

Specifically, fundamental frequency here can be 50hz, then the frequency of nth harmonic is n*50hz.Certainly, base here Wave frequency can also be other numerical value, and this utility model here is not particularly limited.

Preferably, n is the odd number more than 9, and harmonic wave high-current generation device 1 includes:

Be connected with host computer 5, for receiving host computer 5 according to the fundamental wave of user input, 3 subharmonic, 5 subharmonic until n The corresponding fundamental wave that generates generates instruction until 7 subharmonic generate instruction and 9-n combined harmonic generates to the parameter of subharmonic respectively First fpga of instruction；

Input is connected with a fpga, for generating, according to fundamental wave, the fundamental power source that instruction generates fundamental signal；

Input is connected with a fpga, for generating, according to 3 subharmonic, 3 subharmonic that instruction generates 3 rd harmonic signal Power source；

Input is connected with a fpga, for generating, according to 5 subharmonic, 5 subharmonic that instruction generates 5 rd harmonic signal Power source；

Input is connected with a fpga, for generating, according to 7 subharmonic, 7 subharmonic that instruction generates 7 rd harmonic signal Power source；

Input is connected with a fpga, generates 9-n combined harmonic letter for generating instruction according to 9-n combined harmonic Number combined harmonic power source；

Respectively with the outfan in fundamental power source, the outfan of 3 subharmonic power sources, the outfan of 5 subharmonic power sources, The outfan of the outfan of 7 subharmonic power sources and combined harmonic power source connects, for believing fundamental signal, 3 subharmonic Number, 5 rd harmonic signal, the 7 rd harmonic signal and 9-n combined harmonic signal current lifting device that coupled and amplified.

It is understood that the harmonic wave high-current generation device 1 that this utility model provides is by each harmonic power source and liter Stream device combines, and wherein, fundamental wave, 3 subharmonic, 5 subharmonic and 7 subharmonic are independently exported by respective harmonic wave electron source, 9-n time combined harmonic synthesizes output by combined harmonic generator after linear power amplifier, and each harmonic passes through current lifting device Export combined harmonic high current after coupling amplification, meet the fundamental wave in harmonic wave high current and the content of each harmonic can be passed through to survey Automatically adjust after amount feedback.

In addition, it is necessary to explanation, in the application, fundamental wave, 3 subharmonic, 5 subharmonic and 7 subharmonic are individually exported, And 9-n subharmonic be combined output be because fundamental wave, 3 subharmonic, 5 subharmonic and 7 subharmonic occupancy volume very big, can account for About the 90% of combined harmonic high current, and the content of 9 harmonic waves afterwards is just considerably less, therefore, 9-n subharmonic is combined defeated Go out.

It is understood that the formula of fundamental wave, 3 subharmonic, 5 subharmonic and 7 subharmonic is as follows:

In formula (1): x_m(t) be m rd harmonic signal, m be overtone order, during m=1 be fundamental wave, m can take 1,3,5 and 7；a_mFor fundamental wave or harmonic amplitude；For fundamental wave or harmonic wave initial phase；ω₀=2 π/t₀,t₀For the signal primitive period.

X in formula (2)₉T () is 9-n combined harmonic signal, n is the odd number of 9≤n≤n.For fundamental wave or harmonic wave initial phase Position；ω₀=2 π/t₀,t₀For the signal primitive period.

It can be seen that, harmonic wave high-current generation device 1 provided herein has the following characteristics that

1) there is the controlled independent harmonic wave electron source synchronous with fundamental wave of phase place；

2) there is the controlled combined harmonic generator synchronous with fundamental wave of phase place；

3) having can be to the current lifting device of multichannel coupling.

The operation principle of this harmonic wave high-current generation device 1 is:

1) first on host computer 5 interface established standardses passage fundamental wave until nth harmonic parameter；

2) host computer 5 will be sent out by udp up to the corresponding harmonic generation instruction of the parameter generation of nth harmonic according to fundamental wave Deliver to a fpga；

3) fundamental power source is until nth harmonic power source generates instruction and harmonic generation instruction life according to corresponding fundamental wave Become corresponding fundamental wave and harmonic wave；

4) current lifting device is compound to fundamental signal, 3 rd harmonic signal, 5 rd harmonic signal, 7 rd harmonic signal and 9-n time humorous Ripple signal is coupled and is amplified.

It is connected with harmonic wave high-current generation device 1, is used for harmonic wave high current is measured, obtain the standard of standard signal Current transformer 2；

Specifically, harmonic wave high current signal obtains standard secondary current signal by standard current transformer 2, this standard two Primary current signal is as standard signal.

It is connected with harmonic wave high-current generation device 1, is used for harmonic wave high current is measured, obtain the tested of measured signal Current transformer 3；

Specifically, harmonic wave high current signal obtains tested secondary current signal by tested current transformer 3, and this tested two Primary current signal is as measured signal.

Preferably, n is 19.

Preferably, standard current transformer 2 is the current transformer of 0.05s level.

Preferably, standard current transformer 2 is high-accuracy current divider.

Specifically, high-accuracy current divider here be precision resister, test when, using the voltage at diverter two ends as Standard signal.

Preferably, tested current transformer 3 is 0.2 grade of current transformer.

Preferably, tested current transformer 3 is electronic current mutual inductor.

It is understood that for standard current transformer 2, can be selected for the current transformer of 0.05s level, for high accuracy Current transformer for, due to its acquisition precision very high it is believed that its collection fundamental wave and harmonic wave very accurate, therefore Can be as the standard of tested current transformer 3, in addition, high-accuracy current divider should be adopted when test frequency is higher than 400hz. Tested current transformer 3 can select different types of current transformer as needed, and tested current transformer 3 can be common 0.2 grade or 0.5 grade of conventional current transformer, alternatively electronic current mutual inductor are it is to be understood that conventional current mutual inductance The output rated secondary current of device can be 5a or 1a, electronic current mutual inductor exportable simulation small voltage also exportable numeral Amount (iec61850 or ft3).

Specifically, refer to Fig. 2 and Fig. 3, wherein, Fig. 2 and Fig. 3 is another kind of Current Mutual Inductance of this utility model offer The structural representation of device harmonic error measuring system.

In Fig. 2 and Fig. 3, ct₀Represent be standard current transformer, its be conventional current transformer, what ctx represented be by Survey current transformer.Mu is the combining unit being connected with electronic current mutual inductor.In sum, what this utility model provided is humorous Ripple current error measurement apparatus, can take into account conventional current transformer and electronic current mutual inductor, have complete test and Multiple miscellaneous functions.Stress_responsive genes precision is reached with 0.1 grade, 0.02 grade of fundamental wave error precision.Export for there being combining unit Electronic current mutual inductor, synchronous and asynchronous measurement mode supported by harmonic current error measuring means, and synchronizing signal is permissible It is input or the pulse per second (PPS) exporting and irig-b.

It is connected with standard current transformer 2 and tested current transformer 3 respectively, be used for turning standard signal and measured signal Change pending signal into and send to the harmonic current measurement device 4 of host computer 5；

Preferably, harmonic current measurement device 4 includes:

Relay module, ad sampling module, the 2nd fpga, stm32 and the switch being sequentially connected, wherein, relay Module includes sampling resistor, and ad sampling module includes adc sampling A/D chip, and switch is connected with host computer 5；

Specifically, ad sampling module here includes 24 high accuracy adc sampling A/D chip.

Harmonic current measurement device 4 also includes:

The synchronization module being connected with the 2nd fpga and ft3 module；

The first electrical network mouth, the second electrical network mouth, the first smooth network interface and the second smooth network interface being connected with switch；

The 3rd smooth network interface being connected with switch by the 3rd fpga.

Specifically, refer to Fig. 4, a kind of harmonic current measurement device that utility model Fig. 4 provides for this utility model Schematic diagram.

Wherein, standard channel data processing:

When standard channel connects standard current transformer 2 analog quantity (5a/1a) port, select 5a range and 1a in host computer 5 Range, host computer 5 passes through udp agreement and sends instruction to stm32, and stm32 is switched to specified according to instruction control relay module Range path, the high current of input changes into voltage signal through sampling resistor and delivers to ad sampling module；Ad sampling module is right first Voltage signal is processed through channel selecting, programming amplifying, differential attenuation etc., is sent to adc sampling A/D chip and (is specifically as follows Ad127x analog-to-digital conversion chip)；2nd fpga controls adc sampling A/D chip that analog sampling value is changed into numeral according to synchronizing signal Amount is simultaneously got off by spi agreement data storage of reading back；Stm32 will be stored in the data in the 2nd fpga using the agreement of fsmc bus The form reading out and being packaged into udp message delivers to host computer 5, carries out calculation process by host computer 5 to standard harmonic amount data；

When standard channel connects simulation small voltage port, the small voltage of input is directly sent to ad sampling module；Ad sampling module After the process such as channel selecting, programming amplifying, differential attenuation, adc sampling A/D chip is sent to voltage signal；2nd fpga according to Synchronizing signal controls adc sampling A/D chip analog sampling value to be changed into digital quantity and gets off by spi agreement data storage of reading back； Stm32 is come and is sent in the form of being packaged into udp message using the data read-out that will be stored in the 2nd fpga of agreement of fsmc bus To host computer 5, calculation process is carried out to standard harmonic amount data by host computer 5；

Tested channel data is processed:

When tested passage connects high current (5a/1a) port, select 5a range and 1a range in host computer 5, host computer 5 passes through Udp agreement sends instruction to stm32, and stm32 is switched to specified range path according to instruction control relay module, input big Electric current changes into voltage signal through sampling resistor and delivers to ad sampling module；Ad sampling module to voltage signal through channel selecting, Programming amplifying, differential attenuation etc. are sent to adc sampling A/D chip after processing；2nd pfga controls adc sampling A/D chip according to synchronizing signal Analog sampling value is changed into digital quantity and gets off by spi agreement data storage of reading back；Stm32 will using the agreement of fsmc bus The form that udp message is carried out and be packaged into the data read-out being stored in the 2nd pfga delivers to host computer 5, by host computer 5 to tested Harmonic content data carries out calculation process；

When tested passage connects simulation small voltage port, the small voltage of input is directly sent to ad sampling module；Ad sampling module After the process such as channel selecting, programming amplifying, differential attenuation, adc sampling A/D chip is sent to voltage signal；2nd pfga according to Synchronizing signal controls adc sampling A/D chip analog sampling value to be changed into digital quantity and gets off by spi agreement data storage of reading back； Stm32 is come and is sent in the form of being packaged into udp message using the data read-out that will be stored in the 2nd pfga of agreement of fsmc bus To host computer 5, calculation process is carried out to tested harmonic content data by host computer 5；

Be measured as digital quantity, using iec61850 agreement, have synchronizing signal when, optical fiber is according to tail optical fiber type (st/sc) It is connected on the first smooth network interface or the second smooth network interface, twisted-pair feeder can be connected on any one electrical network mouth (the first electrical network mouth or second Electrical network mouth) on, iec61850 message is directly sent to host computer 5 by switch, by host computer 5 analytic message, takes out tested humorous Ripple amount data, row operation of going forward side by side is processed；Be measured as digital quantity, using iec61850 agreement, no synchronizing signal when, optical fiber is connect (only support sc mouth on the 3rd smooth network interface)；Iec61850 message is delivered at the 3rd pfga, by the 3rd pfga analytic message and Inside delivers to host computer 5 by network interface through switch again plus temporal information, and host computer 5 is according to the tested harmonic content in message Data and temporal information carry out calculation process；

When being measured as digital quantity using ft3 agreement, from ft3 port, ft3 signal is sent after opto-electronic conversion by signal To on the 2nd pfga, the data that inside comprises is taken out and is stored by parsing ft3 message by the 2nd pfga, is adopted by stm32 After reading to walk by data with fsmc bus protocol, the form being packaged into udp message in stm32 delivers to host computer 5, and host computer 5 will Tested harmonic content data in udp message parses and carries out calculation process.

It is connected with harmonic wave high-current generation device 1 and harmonic current measurement device 4 respectively, be used for according to pending signal Obtain the content up to nth harmonic for the fundamental wave, the host computer 5 than difference and the error of angular difference.

It is understood that the pending signal that host computer 5 transmits to harmonic current measurement device 4 carries out Fourier transformation Computing, just can calculate content, ratio difference and the angular difference of fundamental wave and each harmonic.

The formula of Fourier transformation is as follows:

$x\left(t\right)=a_0+\underset{n=1}{\overset{\mathrm{\∞}}{\σ}}(a_n\cos {\mathrm{n\ω}}_{0}t+b_n\sin {\mathrm{n\ω}}_{0}t),n=1,2,3,...$

Fourier coefficient:

$a_0=\frac{1}{t}{\&integral;}_{-\frac{t}{2}}^{\frac{t}{2}}x\left(t\right)dt$

$a_n=\frac{2}{t}{\&integral;}_{-\frac{t}{2}}^{\frac{t}{2}}x\left(t\right)\cos n{\mathrm{\ω}}_{0}tdt$

$b_n=\frac{2}{t}{\&integral;}_{-\frac{t}{2}}^{\frac{t}{2}}x\left(t\right)\sin {\mathrm{n\ω}}_{0}tdt$

In formula: t is the cycle；ω₀For fundamental frequency, ω₀=2 π/t₀,t₀For the signal primitive period.

Another kind of form of trigonometric function expansion:

In formula: a₀For the DC component of signal, a_nFor nth harmonic amplitude, n ω is nth harmonic frequency,For nth harmonic phase Angle,For nth harmonic.

The ratio declinate of fundamental wave and each harmonic is poor:

In formula: k_nPoor, the δ for nth harmonic ratio_nFor nth harmonic angular difference.

It can be seen that, the impact to current transformer for the nth harmonic can be obtained according to the content of nth harmonic, than difference and angular difference, I.e. current transformer gathers error during nth harmonic.

In addition, host computer 5 meets multiple test requests, rich interface, fundamental wave and harmonic wave can be carried out to various electron sources The control of content, and automatically carry out slope according to setting, receive various electricity and the error that stress_responsive genes instrument sends simultaneously Data signal, forms test record inside local data base, facilitates follow-up analysis and inquiry.

To sum up, the big electricity of harmonic wave that harmonic wave high-current generation device produces according to harmonic wave mechanism can be known in this utility model Stream, can know harmonic wave to current transformer once, the impact of secondary current signal, and then obtain harmonic wave to tested Current Mutual Inductance The impact of error (ratio difference, angular difference) between the standard signal of the measured signal of device output and standard current transformer output；Energy Enough know the ratio to measured signal and standard signal under the analysis of harmonic signal and each harmonic for the harmonic current error measuring means Value difference, angular difference.

This utility model provides a kind of current transformer harmonic error measuring system, and this system is included for generating harmonic wave The harmonic wave high-current generation device of high current；For measuring to harmonic wave high current, the normalized current obtaining standard signal is mutual Sensor；For measuring to harmonic wave high current, obtain the tested current transformer of measured signal；For by standard signal and quilt Survey signal to be converted into pending signal and send to the harmonic current measurement device of host computer；For obtaining according to pending signal The content up to nth harmonic for the fundamental wave, the host computer than difference and angular difference.It can be seen that, the application passes through to generate the harmonic wave of harmonic wave high current High-current generation device simulating power system environment, then according to the tested Current Mutual Inductance respectively harmonic wave high current being measured Measured signal that device and standard current transformer record and standard signal obtain fundamental wave and nth harmonic content, than difference and Angular difference, by the comparison with standard current transformer, just would know that error when to harmonic measure for the current transformer, and then Error (ratio between the standard signal of the measured signal tested current transformer being exported to harmonic wave and standard current transformer output Value difference, angular difference) impact, convenient subsequently tested current transformer is improved and the accurate measurement to harmonic wave.

It should be noted that in this manual, such as first and second or the like relational terms are used merely to one Individual entity or operation are made a distinction with another entity or operation, and not necessarily require or imply these entities or operate it Between there is any this actual relation or order.And, term " inclusion ", "comprising" or its any other variant are intended to Cover comprising of nonexcludability, so that including a series of process of key elements, method, article or equipment not only include those Key element, but also include other key elements being not expressly set out, or also include for this process, method, article or set Standby intrinsic key element.In the absence of more restrictions, the key element that limited by sentence "including a ..." it is not excluded that Also there is other identical element in process, method, article or the equipment including described key element.

Described above to the disclosed embodiments, makes professional and technical personnel in the field be capable of or new using this practicality Type.Multiple modifications to these embodiments will be apparent from for those skilled in the art, is determined herein The General Principle of justice can be realized in the case of without departing from spirit or scope of the present utility model in other embodiments.Cause This, this utility model is not intended to be limited to the embodiments shown herein, and is to fit to and principles disclosed herein The wide scope consistent with features of novelty.

Claims (8)

1. a kind of current transformer harmonic error measuring system is it is characterised in that include:

For receiving and according to the fundamental wave of user input to host computer, 3 subharmonic, 5 subharmonic until the parameter of nth harmonic generates The harmonic wave high-current generation device of harmonic wave high current, wherein, described parameter includes described fundamental wave until the content of nth harmonic, width Value, phase place and frequency, n is the odd number not less than 3；

It is connected with described harmonic wave high-current generation device, is used for described harmonic wave high current is measured, obtain standard signal Standard current transformer；

It is connected with described harmonic wave high-current generation device, is used for described harmonic wave high current is measured, obtain measured signal Tested current transformer；

Be connected with described standard current transformer and described tested current transformer respectively, for by described standard signal and described Measured signal is converted into pending signal and sends to the harmonic current measurement device of described host computer；

It is connected with described harmonic wave high-current generation device and described harmonic current measurement device respectively, be used for waiting to locate according to described Reason signal obtains described fundamental wave until the content of nth harmonic, ratio are poor and the described host computer of angular difference.

2. current transformer harmonic error measuring system as claimed in claim 1 is it is characterised in that n is the odd number more than 9, Described harmonic wave high-current generation device includes:

Be connected with described host computer, for receive described host computer according to the fundamental wave of user input, 3 subharmonic, 5 subharmonic until The corresponding fundamental wave that generates generates instruction until 7 subharmonic generate instruction and 9-n combined harmonic generates to the parameter of nth harmonic respectively First fpga of instruction；

Input is connected with a described fpga, for generating, according to described fundamental wave, the fundamental power that instruction generates fundamental signal Source；

Input is connected with a described fpga, for generating, according to 3 subharmonic, 3 subharmonic that instruction generates 3 rd harmonic signal Power source；

Input is connected with a described fpga, for generating, according to 5 subharmonic, 5 subharmonic that instruction generates 5 rd harmonic signal Power source；

Input is connected with a described fpga, for generating, according to described 7 subharmonic, 7 times that instruction generates 7 rd harmonic signal Harmonic power source；

Input is connected with a described fpga, for according to described 9-n combined harmonic generate instruction generate 9-n time be combined humorous The combined harmonic power source of ripple signal；

Respectively with the outfan in described fundamental power source, the outfan of 3 subharmonic power sources, the outfan of 5 subharmonic power sources, The outfan of the outfan of 7 subharmonic power sources and combined harmonic power source connects, for by described fundamental signal, 3 times humorous The current lifting device that ripple signal, 5 rd harmonic signal, 7 rd harmonic signal and 9-n combined harmonic signal are coupled and amplified.

3. current transformer harmonic error measuring system as claimed in claim 2 is it is characterised in that n is 19.

4. current transformer harmonic error measuring system as claimed in claim 2 is it is characterised in that described normalized current mutual inductance Device is the current transformer of 0.05s level.

5. current transformer harmonic error measuring system as claimed in claim 2 is it is characterised in that described normalized current mutual inductance Device is high-accuracy current divider.

6. current transformer harmonic error measuring system as claimed in claim 2 is it is characterised in that described tested Current Mutual Inductance Device is 0.2 grade of current transformer.

7. current transformer harmonic error measuring system as claimed in claim 2 is it is characterised in that described tested Current Mutual Inductance Device is electronic current mutual inductor.

8. the current transformer harmonic error measuring system as described in any one of claim 1-7 is it is characterised in that described harmonic wave Current measuring device includes:

Relay module, ad sampling module, the 2nd fpga, stm32 and the switch being sequentially connected, wherein, described relay Module includes sampling resistor, and described ad sampling module includes adc sampling A/D chip, and described switch is connected with described host computer；

Described harmonic current measurement device also includes:

The synchronization module being connected with described 2nd fpga and ft3 module；

The first electrical network mouth, the second electrical network mouth, the first smooth network interface and the second smooth network interface being connected with described switch；

The 3rd smooth network interface being connected with described switch by the 3rd fpga.