CN2800285Y - Line power frequency parameter tester - Google Patents
Line power frequency parameter tester Download PDFInfo
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- CN2800285Y CN2800285Y CN 200520096324 CN200520096324U CN2800285Y CN 2800285 Y CN2800285 Y CN 2800285Y CN 200520096324 CN200520096324 CN 200520096324 CN 200520096324 U CN200520096324 U CN 200520096324U CN 2800285 Y CN2800285 Y CN 2800285Y
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Abstract
The utility model relates to a line power frequency parameter testing instrument, which comprises the output end of a three phase electricity, a testing power supply with a three phase output, and a measuring section used for measuring the parameter of the output end of the three phase electricity, wherein the output end of the testing power supply is connected with the output end of the three phase electricity, the testing power supply is the testing power supply which can output an alternating current of the three phase frequency conversion of a sine pulse width modulating wave, and the testing power supply adopts the testing power supply which can output the alternating current of the three phase frequency conversion of the sine pulse width modulating wave; a frequency conversion test has the characteristics that the frequency of a current signal injected into a test line is changed, and a test frequency is different from a power frequency (the output frequency of the power frequency is 50Hz), which can eliminate the influence of power frequency interference; thereby, the size of the section of the testing power supply is reduced, the size of line power frequency parameter testing instrument is reduced and the utility model has the advantages of light weight and portability.
Description
Technical field
The utility model relates to the High-Voltage Technology field, especially for the testing apparatus of measurement circuit power frequency parameter.
Background technology
Circuit power frequency parameter measurement equipment directly hinders isoparametric measuring equipment for positive sequence open circuit, positive sequence short circuit, zero sequence open circuit, zero sequence short circuit, the circuit of measuring high-voltage circuit.Circuit power frequency parameter measurement equipment generally is made up of testing power supply, measure portion.
In circuit power frequency parameter test process, because test line is subjected to the influence of adjacent lines or other outlet of transformer station, there are electric current and voltage disturbance on the circuit with system same frequency rate (power frequency 50Hz), in order to offset the influence that this interference brings, testing power supply need increase the power current of injection or improve test voltage improving signal to noise ratio (S/N ratio), and big measuring current and high test voltage must cause testing power supply part bulky of measuring equipment.As existing circuit power frequency parameter test equipment, often use three-phase regulator and 10kV substation transformer as testing power supply, testing apparatus is heavy to can't bear, and needs truck transport, the on-the-spot loading and unloading of jack lift.Work brings great inconvenience to site test for this, brings hidden danger also for the safe operation of transformer station, operating personnel's personal safety.
The compactness day by day in present transmission of electricity corridor, power frequency during parameter measurement disturbs (electrostatic induction and electromagnetic induction) abominable day by day, recently realize disturbing the difficulty of inhibition to strengthen by increasing substantially noise, and can bring bigger error to measurement result, also the capacity requirement to testing power supply strengthens.
In addition, the existing line power frequency parameter measuring partly is generally the electrical instrument (as: reometer, voltage table etc.) of pointer-type, needs artificial reading, and reading randomness height influences the result of parameter measurement.
Summary of the invention
Technical problem to be solved in the utility model is: a kind of circuit power frequency parameter tester is provided, and this circuit power frequency parameter tester volume is little, in light weight, is easy to carry.
The utility model solves the problems of the technologies described above the technical scheme that is adopted:
A kind of circuit power frequency parameter tester, it comprises the three-phase electricity output terminal, have three-phase output testing power supply, be used to measure the measure portion of parameter on the three-phase electricity output terminal; The testing power supply output terminal is connected with the three-phase electricity output terminal; Testing power supply is the testing power supply of the three phase variable frequency alternating current of output sinusoidal pulse width modulation ripple.
In the such scheme, the circuit of testing power supply comprises from the input end to the output terminal successively:
Be used for civil power be transformed to galvanic interchange-DC converting part,
Be used for direct current be transformed to galvanic DC-to-DC conversion fraction,
Be used for direct current is transformed to the AC/DC frequency conversion conversion fraction of the three phase variable frequency alternating current of sinusoidal pulse width modulation ripple.
In the such scheme, be provided with three isolated change outputs between testing power supply output terminal and the three-phase electricity output terminal.
In the such scheme, be provided with three-phase output filtering part between testing power supply output terminal and the three-phase electricity output terminal.
In the such scheme, tester also comprises the control power supply that direct supply is provided to tester inside.
In the such scheme, tester also comprises and offers the three phase sine pulse width modulation controlled module of DC-to-DC conversion fraction power model as switch controlling signal.
In the such scheme, tester also comprises the online programmable circuit of control control power supply.
In the such scheme, measure portion comprises industrial computer and voltage sensor, current sensor; The output terminal of voltage sensor, current sensor is through signal modulation, A/D conversion input industrial computer.
In the such scheme, voltage sensor, current sensor comprise that the voltage sensor of three tunnel phases and current sensor, one road mutual voltage sensor and current sensor, a tunnel directly hinder voltage sensor and current sensor.
In the such scheme, testing power supply is that output frequency is 52.5Hz.
The utility model circuit power frequency parameter tester compared with prior art has the following advantages:
1, testing power supply adopts the testing power supply of the three phase variable frequency alternating current that can export the sinusoidal pulse width modulation ripple, the characteristics of frequency conversion test are to change the frequency that is injected into current signal in the test circuit, test frequency differs from power frequency (output frequency is 50Hz), can remove the influence that power frequency is disturbed, therefore, the volume of testing power supply part reduces greatly, and the volume of circuit power frequency parameter tester is also reduced greatly, weight alleviates greatly, is easy to carry.
2, testing power supply comprises: interchange-DC converting part, DC-to-DC conversion fraction, AC/DC frequency conversion conversion fraction, and circuit design is simple, and volume is little.
The function of interchange-DC converting part (AC to DC rectifying conversion part) is to realize the direct supply of system's civil power (220V AC power) rectifying conversion for fixing output; The function of DC-to-DC conversion fraction (DC to DC conversion fraction) is to realize that rectifying conversion is obtained unsettled direct supply carries out the voltage stabilizing processing, and voltage transformation extremely is fit to the stable amplitude that output requires; The function of AC/DC frequency conversion conversion fraction (DC to AC frequency conversion conversion fraction) is to realize with the constant voltage dc source inversion being the three-phase alternating-current supply that is output as the sinusoidal pulse width modulation ripple.
3, be provided with three isolated changes (output) between testing power supply output terminal and the three-phase electricity output terminal, can realize the output of sinusoidal pulse width modulation ripple is filtered into the sinusoidal waveform with certain level and smooth degree through LC.
4, the three-phase isolation transformer output can be realized the output of previous stage and measurand are carried out isolation on electric, simultaneously carry out the voltage magnitude conversion according to designing requirement, and, utilize the further filtering of leakage inductance of transformer by at output stage filter capacitor in parallel.
5, control power conversion module can provide tester work required inside direct supply.
6, measure portion comprises industrial computer and voltage sensor, current sensor; The output terminal of voltage sensor, current sensor is through signal modulation, A/D conversion input industrial computer, the measurement of realization plurality of voltages, current amplitude and phase place and computing etc.
The utility model circuit power frequency parameter tester can independently be finished the work of circuit power frequency parameter measuring.
Description of drawings
Fig. 1 is the structured flowchart of the utility model circuit power frequency parameter tester embodiment
Fig. 2 is the functional block diagram of testing power supply
Fig. 3 is the circuit theory diagrams of testing power supply
Fig. 4 is the structured flowchart of measure portion
Fig. 5 is a PID link schematic diagram
Fig. 6 is a sinusoidal pulse width modulation waveform generation schematic diagram
Embodiment
The utility model patent as shown in Figure 1, it comprises the electric output terminal of three-phase (A phase, B phase, C phase), have three-phase output testing power supply, be used to measure parameter on the three-phase electricity output terminal measure portion, provide the control power supply of direct supply, the online programmable circuit (online programming module controls) of control control power supply to tester inside; The testing power supply output terminal is connected with the three-phase electricity output terminal; Testing power supply is the testing power supply of three phase variable frequency (output frequency the is 52.5Hz) alternating current of output sinusoidal pulse width modulation ripple.
As shown in Figure 2, the circuit of testing power supply comprises from the input end to the output terminal successively: be used for civil power (220V single phase alternating current power supply) is transformed to galvanic interchange-DC converting part (AC to DC rectifying conversion part), is used for direct current is transformed to galvanic DC-to-DC conversion fraction (DC to DC conversion fraction), is used for direct current is transformed to the AC/DC frequency conversion conversion fraction (DC to AC frequency conversion conversion fraction) of the three phase variable frequency alternating current of sinusoidal pulse width modulation ripple.
As shown in Figure 4, measure portion comprises industrial computer and sensor circuit (voltage sensor, current sensor); The output terminal of voltage sensor, current sensor is through switching controls module, signal modulation, A/D conversion (multi-channel data acquisition module) input industrial computer control core circuit.
The circuit of testing power supply as shown in Figure 3, the design of AC to DC rectifying conversion part (A part) is fairly simple, the single-phase AC 220V power supply of input is obtained dc rectification power through behind the rectifier bridge, the load characteristic of this rectifier power source is very poor, can not be used for directly offering DC to AC (C part) frequency conversion conversion fraction, therefore be provided with DC to DC (B part) conversion fraction intermediate conversion link.
DC to DC conversion fraction is transformed to the stable dc power supply that specific voltage is exported with input, is the automatic control system with feedback element, and it is made up of four major parts: IPM high frequency chopping, high frequency intermediate transformer, high-frequency rectification, High frequency filter.
DC to AC frequency conversion conversion fraction is the most key link of variable-frequency power sources, the setting of frequency, the adjusting of output voltage all are to realize by this joint, though the power component of this part is few, but very important, multinomial performance indexs such as the each harmonic content of power supply, frequency stability are all by this part design decision.
Rectifier bridge and main electrochemical capacitor C1 that D1-D4 forms can choose by common rectification circuit, getting rectifier bridge in the side circuit is the KBPC3510 rectifier bridge, C1 selects the high-frequency electrolysis electric capacity parallel connection of 3 680uF for use, high-frequency electrolysis electric capacity has low inside equivalent resistance and equivalent series inductance value, this is the major reason that high-frequency current causes the electrochemical capacitor heating, and selecting for use of C2 is identical with C1.
T1-T4 is the IGBT device, is integrated in the encapsulation, with in overheated and part overcurrent protection testing circuit integration module together, is called the IPM intelligent object in the commercial production.To consider that when selecting the IPM module for use its maximum can be born peak point current and maximum is turn-offed the surge voltage kurtosis; in the practical application at the module two ends custom-designed buffer circuit in parallel as voltage protection to reduce maximum surge spike, selecting for use of T5-T8 is identical with T1-T4.
Commutator tube D5-D8 is different from common commutation diode, is operated under the high-frequency current state, must select anti-phase release time of short fast extensive pipe with soft recovery characteristics in the electric current tolerance range for use, and is equipped with corresponding buffer circuit reduction voltage jump spike.
Inductance L and capacitor C 2 are formed filtering circuit, and its value should be selected according to the cross-over frequency and the filter effect of system, and inductor iron core adopts the high permeability material ferrite to make.(below remove)
Consider that by above principle it is as follows to calculate the back selected parameter:
The inversion intelligent object is selected Mitsubishi PM30CSJ060 (30A/600V) for use;
D5-D8 selects for use the DSEI60-10A of IXYS company type to recover pipe soon;
C1, C2 select 3 680uF Hitachi high-frequency electrolysis electric capacity parallel connections respectively for use;
L selects 1.5mH/8A/30KHz ferrite intermediate frequency inductance for use.
At control section, most crucial is the PWM copped wave module and the DC to AC link SPWM Sine Wave Pulse Width Modulation module of DC to DC link, and the former realizes voltage transformation and voltage stabilizing function, and the latter realizes DC/AC conversion and frequency modulation and voltage modulation function; The design of fault secure circuit is the reliable assurance that system is able to safe operation.
The PWM control circuit of chopping is made up of renewal product SG3525A and the peripheral circuit of PWM special chip SG3524.Compare with SG3524, the many performances and the function of this chip are promoted: set up under-voltage locking, slow start circuit, improved the width modulation comparer and the error amplifier interference free performance greatly strengthens, switching frequency can be up to 200KHz, be more outstanding PWM special chip at present.
PWM copped wave Control work is in the feedback system of closed loop, for the constant load under the alternating voltage, approximately can be equivalent to the situation of the continuous varying duty of size under the constant voltage, this dynamic stability to power control system is an acid test, controlled variable will at every moment be followed the tracks of the variation of output and be changed, and open-loop control system is not satisfy this requirement.For guaranteeing the stability and the dynamic quality of output voltage, introduce feedback element and cascade compensation link and form closed loop automatic control system.The quality of the precision of feedback element and characteristic direct control system requires the measuring sensor of feedback element to have measuring accuracy height, stability of characteristics, sensitive performance.The effect of cascade compensation link is to make deviation according to dynamic quality or the steady-state behaviour of certain rules operation with the improvement system.The cascade compensation device that PID in this testing power supply (ratio, integration, differential) regulator comes to this.As shown in Figure 5, the PID regulator is combined by ratio, integration, differentiating circuit.
Test shows, only there is PI to regulate the requirement that at all can't satisfy system performance, its output voltage waveforms is along with the size of output current produces corresponding distortion, the output current of waveform point is big more, this position voltage waveform criterion distance sine wave (this position is positioned at the summit and the peak valley of waveform when pure resistive load) far away more.For this reason, on the basis of proportional plus integral control, increased differentiation element, though increased the complicacy of circuit, the dynamic property of elevator system.Here, we realize the PID function by same operational amplifier.
Find in the debugging, single phase alternating current power supply on dynamic parameter complicacy and susceptibility considerably beyond direct supply, also on the basis of calculating, carefully and repeatedly be adjusted just for each parameter of PID link and can be obtained satisfied result.
SPWM is the english abbreviation of Sine Wave Pulse Width Modulation, and the effect of inversion unit is that direct current is become alternating current, in order to obtain the sine wave of standard in output, need carry out the control of certain rule to inversion unit, and this process is called sinusoidal pulse width modulation.The Sine Wave Pulse Width Modulation inversion becomes the high-frequency impulse (as Fig. 6) that a series of constant amplitudes, width change according to sinusoidal rule to output, integration is carried out in these pulses, its effect is equivalent to sine wave, if installing wave filter additional in output filters radio-frequency component, then can obtain level and smooth sine wave.
The key that realizes the SPWM inversion is the drive signal that obtains according to the rule variation, that is to say sinusoidal pulse width modulation signal (SPWM).The way that obtains the SPWM signal has a variety of; dividing from the circuit form that produces is nothing but analog form, digital form, digital-to-analogue hybrid mode; no matter be which kind of method; their principle all is the same; promptly the size by standard of comparison sine wave (modulating wave) and high frequency triangle wave (carrier wave) instantaneous value obtains a series of pulse signals; certainly, this series of pulses that obtains can not also must protect directly as the drive signal of switch through the dead band, allocation process or the like.Figure XX has provided its modulation principle, and as space is limited, principle is in this just no longer narration.
Special three-phase SPWM chip HEF4752 makes with this part function in the company that has phase a little earlier, and along with the development of technology, this chip is eliminated.Everybody popular employing high-speed microprocessor or industrial computer scheme realize at present, but design is complicated, and the construction cycle is long; We find that during the process of the investigation Britain MITEL company has newly released a kind of chip SA866AE that is used for the electric machine speed regulation aspect, and we successfully are applied to it in the design of testing power supply after the careful analysis to this product.This scheme only needs the SA866AE chip of a slice PLCC32 encapsulation and the serial EEPROM of a slice DIP8 encapsulation, and the area of SPWM core in printed board that this two chips is formed be 2 square centimeters of less thaies still, are light and practical.This scheme not only possesses the function that produces the SPWM ripple, also is integrated with functions such as signal allocation, dead band control, pulse cancellation, failure monitoring, should be the SPWM solution of an outstanding practicality.
As shown in Figure 2, be provided with three isolated change outputs, three-phase alternating current output filtering part, fault detect warning circuit between testing power supply output terminal and the three-phase electricity output terminal.
The function of fault detect warning circuit is to detect faults such as output overloading in the Power Operating Process, short circuit, power device overcurrent in real time, and the power cutoff control signal, provides the fault alarm prompting.The emergency protection type of the fault detect warning circuit among the utility model embodiment has: output over-voltage protection, output overcurrent protection, overload protection, IPM overcurrent protection, direct current arm overvoltage protection, the overcurrent protection of direct current arm; in case surpass definite value, at first turn-off the driving circuit of IPM.
Also comprise among the utility model embodiment and offer three phase sine pulse width modulation controlled module and the online programmable circuit of DC-to-DC conversion fraction power model as switch controlling signal.
The function of three phase sine pulse width modulation controlled module is to produce the not wide square-wave signal of series of a certain specific fundamental frequency according to measuring needs, and offers the IPM power model as switch controlling signal.
The function of the extensive online programmable circuit of FPGA is a needed logic when realizing the control power work.
As shown in Figure 4, voltage sensor, current sensor comprise that the voltage sensor of three tunnel phases and current sensor, one road mutual voltage sensor and current sensor, a tunnel directly hinder voltage sensor and current sensor.
Claims (10)
1, a kind of circuit power frequency parameter tester, it comprises the three-phase electricity output terminal, have three-phase output testing power supply, be used to measure the measure portion of parameter on the three-phase electricity output terminal; The testing power supply output terminal is connected with the three-phase electricity output terminal; It is characterized in that: testing power supply is the testing power supply of the three phase variable frequency alternating current of output sinusoidal pulse width modulation ripple.
2, tester as claimed in claim 1 is characterized in that: the circuit of testing power supply comprises from the input end to the output terminal successively:
Be used for civil power be transformed to galvanic interchange-DC converting part,
Be used for direct current be transformed to galvanic DC-to-DC conversion fraction,
Be used for direct current is transformed to the AC/DC frequency conversion conversion fraction of the three phase variable frequency alternating current of sinusoidal pulse width modulation ripple.
3, tester as claimed in claim 1 is characterized in that: be provided with three isolated change outputs between testing power supply output terminal and the three-phase electricity output terminal.
4, tester as claimed in claim 1 is characterized in that: be provided with three-phase output filtering part between testing power supply output terminal and the three-phase electricity output terminal.
5, tester as claimed in claim 1 is characterized in that: tester also comprises the control power supply that direct supply is provided to tester inside.
6, tester as claimed in claim 2 is characterized in that: tester also comprises and offers the three phase sine pulse width modulation controlled module of DC-to-DC conversion fraction power model as switch controlling signal.
7, tester as claimed in claim 5 is characterized in that: tester also comprises the online programmable circuit of control control power supply.
8, tester as claimed in claim 1 is characterized in that: measure portion comprises industrial computer and voltage sensor, current sensor; The output terminal of voltage sensor, current sensor is through signal modulation, A/D conversion input industrial computer.
9, tester as claimed in claim 8 is characterized in that: voltage sensor, current sensor comprise that the voltage sensor of three tunnel phases and current sensor, one road mutual voltage sensor and current sensor, a tunnel directly hinder voltage sensor and current sensor.
10, tester as claimed in claim 1 is characterized in that: testing power supply is that output frequency is 52.5Hz.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200520096324 CN2800285Y (en) | 2005-05-16 | 2005-05-16 | Line power frequency parameter tester |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200520096324 CN2800285Y (en) | 2005-05-16 | 2005-05-16 | Line power frequency parameter tester |
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| CN2800285Y true CN2800285Y (en) | 2006-07-26 |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101034117B (en) * | 2007-04-02 | 2010-05-19 | 武汉大学 | Power transmission line power frequency parameters measuring method and device |
| CN102129223B (en) * | 2010-01-16 | 2013-08-21 | 鸿富锦精密工业（深圳）有限公司 | Input device and environmental monitoring system with same |
| CN103645406A (en) * | 2013-12-27 | 2014-03-19 | 国家电网公司 | Level testing system |
| CN103675535A (en) * | 2013-12-02 | 2014-03-26 | 国家电网公司 | High-tension transmission line power frequency parameter testing and testing connection switching integrated device |
| TWI487925B (en) * | 2009-06-16 | 2015-06-11 | Intersil Inc | Component fault detection for use with a multi-phase dc-dc converter |
| CN106291012A (en) * | 2016-08-26 | 2017-01-04 | 深圳市伊力科电源有限公司 | Programmable DC power supply realizes system and method |
| CN107462843A (en) * | 2016-06-03 | 2017-12-12 | 北京中和卓远科技有限公司 | A kind of airborne three-phase alternating-current supply parameter collecting method |
-
2005
- 2005-05-16 CN CN 200520096324 patent/CN2800285Y/en not_active Expired - Fee Related
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101034117B (en) * | 2007-04-02 | 2010-05-19 | 武汉大学 | Power transmission line power frequency parameters measuring method and device |
| TWI487925B (en) * | 2009-06-16 | 2015-06-11 | Intersil Inc | Component fault detection for use with a multi-phase dc-dc converter |
| CN102129223B (en) * | 2010-01-16 | 2013-08-21 | 鸿富锦精密工业（深圳）有限公司 | Input device and environmental monitoring system with same |
| CN103675535A (en) * | 2013-12-02 | 2014-03-26 | 国家电网公司 | High-tension transmission line power frequency parameter testing and testing connection switching integrated device |
| CN103645406A (en) * | 2013-12-27 | 2014-03-19 | 国家电网公司 | Level testing system |
| CN107462843A (en) * | 2016-06-03 | 2017-12-12 | 北京中和卓远科技有限公司 | A kind of airborne three-phase alternating-current supply parameter collecting method |
| CN106291012A (en) * | 2016-08-26 | 2017-01-04 | 深圳市伊力科电源有限公司 | Programmable DC power supply realizes system and method |
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