CN113783441A - Three-phase vienna rectifier carrier discontinuous pulse width modulation - Google Patents
Three-phase vienna rectifier carrier discontinuous pulse width modulation Download PDFInfo
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
- H02M7/02—Conversion of ac power input into dc power output without possibility of reversal
- H02M7/04—Conversion of ac power input into dc power output without possibility of reversal by static converters
- H02M7/12—Conversion of ac power input into dc power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M7/21—Conversion of ac power input into dc power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
- H02M7/217—Conversion of ac power input into dc power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M7/2176—Conversion of ac power input into dc power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only comprising a passive stage to generate a rectified sinusoidal voltage and a controlled switching element in series between such stage and the output
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
- Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
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Abstract
The invention discloses two kinds of carrier interrupted pulse width modulation of three-phase Vienna rectifiers, which comprise a zero-crossing clamping type and a peak value clamping type; the zero-crossing clamping type carrier discontinuous pulse width modulation clamping area is positioned near the zero crossing point and the peak point of the input current, so that the zero-crossing distortion of the input current can be improved; the peak value clamping type carrier interrupted pulse width modulation clamping area is positioned at the maximum phase of the input current, so that the switching loss can be reduced to the maximum extent, and the efficiency is highest. The zero sequence components required to be injected by two types of modulation are realized by one expression, compared with other intermittent pulse width modulation, the method is simple to realize, the execution time of a modulation program is shortened, the calculation burden of a digital controller is lightened, and the method is suitable for the high-switching-frequency AC/DC converter of a wide-bandgap device.
Description
Technical Field
The invention belongs to the technical field of power electronic converters, and particularly relates to a control method of a three-phase Vienna rectifier.
Background
The three-phase Vienna rectifier has the advantages of simple circuit structure, small quantity of switching devices, no direct connection problem, high power density and high reliability, and is widely applied to the fields of aviation and electric automobiles. In order to obtain higher power density, the switching frequency of the converter based on the wide bandgap devices such as silicon carbide and gallium nitride is often several times that of the converter based on the traditional silicon device, and the control period is correspondingly shortened. Also in aviation primary power applications, it is often desirable for the converter to have a higher switching frequency. On one hand, the high switching frequency can reduce the volume and weight of the converter and obtain higher power density; on the other hand, the fundamental frequency of the aviation power grid is higher, and the high switching frequency can help to reduce current harmonic distortion and improve the power factor. However, a high switching frequency will cause higher switching loss, reduce system efficiency, and also impose a great burden on the digital processor.
Discontinuous Pulse Width Modulation (DPWM) selects only one small vector each time during vector synthesis, and the switching tube of each phase does not act in 1/3 fundamental wave period, thereby effectively reducing switching loss. In addition, Carrier-based pulse width modulation (CB-DPWM) is simpler than space vector-based modulation calculation, easier to implement in software, and especially advantageous in high-frequency converters based on wide-bandgap devices. Prior art documents "Lee J, Lee K.Carrier-based discrete PWM methods for Vienna receivers [ J ], IEEE Transactions on Power Electronics, 2015, 30 (6): 2896 and 2900,' an intermittent carrier modulation is provided, the zero-crossing phase is clamped to the midpoint of the direct current side, the problem that the voltage and the current of the Vienna rectifier have different phases is solved, the judgment condition is increased, and the algorithm becomes complicated. Prior art documents "Lee J, Lee K. Performance analysis of carrier-based discrete PWM methods for video receivers with neutral-point voltage balance [ J ]. IEEE Transactions on Power Electronics, 2016, 31 (6): 4075-. Documents "Li K, Wei M, Xie C, et al. triangle Carrier-Based DPWM for Three-Level NPC Inverter [ J ], IEEE Journal of emitting and Selected Topics in Power Electronics, 2018, 6 (4): 1966-. Therefore, it is necessary to research a simplified carrier chopper pulse width modulation algorithm to reduce the calculation burden of the digital controller.
Disclosure of Invention
In order to solve the technical problems mentioned in the background art, the invention provides two kinds of carrier discontinuous pulse width modulation of a three-phase vienna rectifier.
In order to achieve the technical purpose, the technical scheme of the invention is as follows:
the zero-crossing clamping type carrier interrupted pulse width modulation calculates the zero-sequence component expression to be injected according to the magnitude relation between three-phase sine modulation waves, and is characterized in that: the three-phase sine modulation wave is shown as formula I, wherein f is the frequency of a power grid; m is the amplitude of the normalized modulation wave, the value of the amplitude is the same as the modulation ratio, and the amplitude is calculated by a formula II;
wherein U isacIs an effective value of the phase voltage of the AC power grid, UdcIs the dc side voltage. By injecting zero sequence components into the three-phase sinusoidal modulation wave, DPWM can be realized by carrier waves. Zero-sequence component u to be injected for zero-crossing clamping type carrier discontinuous pulse width modulationoffset1Calculating according to formula III;
uoffset1＝(0.5-0.5sign(umid))×(1-urmax)-(0.5+0.5sign(umid))×urminformula III
In the formula umidIs the median value of the three-phase sine modulated wave in formula I, sign (u)mid) The function is a sign-taking function when umidWhen the value of (d) is greater than 0, sign (u)mid) The output value is 1; when u ismidWhen the value of (d) is less than 0, sign (u)mid) The output value is-1; u. ofrmaxIs urxMaximum value of (1), urminIs urxMinimum value of (1), urx(x ═ a, b, c) calculated from formula IV;
urx＝umx+0.5-0.5sign(umx) Wherein x is a, b, c formula IV
Calculating the three-phase sine modulation wave after the zero-sequence component is injected according to a formula V;
in the formula uref_xAnd (x ═ a, b and c) are three-phase sine modulation waves of zero-crossing clamped carrier discontinuous pulse width modulation.
Further, the peak value clamping type carrier discontinuous pulse width modulation calculates and obtains a zero sequence component expression to be injected through the magnitude relation between three-phase sine modulation waves, and is characterized in that: clamping the input current maximum phase, its zero-sequence component u to be injectedoffset2Calculated from formula VI;
umaxand uminInjecting zero sequence component u for the maximum and minimum of three-phase sine wave in formula Ioffset2Calculating the later three-phase sine modulation wave according to a formula VII;
in the formula uref_xAnd (x ═ a, b and c) are three-phase sine modulation waves of peak clamping type carrier discontinuous pulse width modulation respectively.
Adopt the beneficial effect that above-mentioned technical scheme brought:
the invention can shorten the execution time of the modulation program and reduce the calculation burden of the digital controller. Therefore, the modulation method designed by the invention is suitable for the occasions of high-power-density and high-efficiency power factor correction, especially for high-frequency Vienna rectifiers or other AC/DC converters based on wide-bandgap devices.
Drawings
FIG. 1 is a schematic diagram of clamping regions of zero-cross clamped carrier CPWM and peak-clamped carrier CPWM;
FIG. 2 is a flow chart of a calculation of carrier discontinuous pulse width modulation;
FIG. 3 is a waveform diagram of a simulation of two modulation algorithms and their circuits according to the present invention;
fig. 4 is a waveform diagram of a steady-state operation experiment using two modulation algorithms and a circuit embodiment thereof.
Detailed Description
The technical scheme of the invention is explained in detail in the following with the accompanying drawings.
The zero-crossing clamping type carrier discontinuous pulse width modulation and the clamping mode are as shown in figure 1(a), and a zero-sequence component expression required to be injected is obtained through calculation of the magnitude relation between three-phase sine modulation waves, and the zero-sequence component expression is characterized in that: the three-phase sine modulation wave is shown as formula I, wherein f is the frequency of a power grid; m is the amplitude of the normalized modulation wave, the value of the amplitude is the same as the modulation ratio, and the amplitude is calculated by a formula II;
wherein U isacIs an effective value of the phase voltage of the AC power grid, UdcIs the dc side voltage. By injecting zero sequence components into the three-phase sinusoidal modulation wave, DPWM can be realized by carrier waves. Zero-sequence component u to be injected for zero-crossing clamping type carrier discontinuous pulse width modulationoffset1Calculating according to formula III;
uoffset1＝(0.5-0.5sign(umid))×(1-urmax)-(0.5+0.5sign(umid))×urminformula III
In the formula umidIs the median value of the three-phase sine modulated wave in formula I, sign (u)mid) The function is a sign-taking function when umidWhen the value of (d) is greater than 0, sign (u)mid) The output value is 1; when u ismidWhen the value of (d) is less than 0, sign (u)mid) The output value is-1; u. ofrmaxIs urxMaximum value of (1), urminIs urxMinimum value of (1), urx(x ═ a, b, c) is calculated from formula IV, and the calculation flow is as in fig. 2;
urx＝umx+0.5-0.5sign(umx) Wherein x is a, b, c formula IV
Calculating the three-phase sine modulation wave after the zero-sequence component is injected according to a formula V;
in the formula uref_xAnd (x ═ a, b and c) are three-phase sine modulation waves of zero-crossing clamped carrier discontinuous pulse width modulation.
Further, the peak value clamping type carrier discontinuous pulse width modulation calculates and obtains a zero sequence component expression to be injected through the magnitude relation between three-phase sine modulation waves, and is characterized in that: clamping the input current maximum phase, its zero-sequence component u to be injectedoffset2Calculated from formula VI;
umaxand uminInjecting zero sequence component u for the maximum and minimum of three-phase sine wave in formula Ioffset2Calculating the later three-phase sine modulation wave according to a formula VII;
in the formula uref_xEach of (x ═ ab, c) is a three-phase sinusoidal modulated wave of the peak-clamped carrier chopper pulse width modulation.
Simulation and experiment, the input voltage of the Vienna rectifier is the standard of an aviation power grid: 115V/400Hz, output voltage of 320V and power of 5 kW; FIG. 3 is a waveform diagram of a simulation of the use of the inventive carrier CPWM strategy at different modulation ratios, uaAnd iaIs the input voltage current umaIs a sinusoidal reference voltage of phase A, uoffsetIs the injected zero-sequence component, uref-aIs an A-phase modulated wave, uAOIs the a phase leg voltage. From fig. 3(a) and fig. 3(b), it can be seen that when the zero-crossing clamped type carrier chopper pulse width modulation is adopted, the modulated wave and the bridge arm voltage are clamped near the current peak value and the zero crossing point, which are consistent with the clamping area of fig. 1 (a); from fig. 3(c) and fig. 3(d), it can be seen that when the inventive peak-clamped carrier chopper pwm is used, the modulated-wave bridge-arm voltage is clamped near the current peak, which is consistent with the clamping area in fig. 1 (b); FIG. 4 is a waveform diagram of an experiment using the inventive carrier CPWM strategy at different modulation ratios, where U is showndc1And Udc2The direct-current-side upper line bus capacitor voltage respectively represents, and it can be seen that when the zero-crossing clamped type carrier intermittent pulse width modulation is adopted, the bridge arm voltage is clamped near the current peak value and the zero crossing point, the current peak value and the zero crossing point are consistent with the clamping area in the figure 1(a), the sine degree of the input current is good, and the accuracy of the zero-crossing clamped type carrier intermittent pulse width modulation is explained; from fig. 4(c) and fig. 4(d), it can be seen that when the peak clamping type carrier discontinuous pulse width modulation of the invention is adopted, the bridge arm voltage is clamped near the current peak value, which is consistent with the clamping area of fig. 1(b), and the sine degree of the input current is good, which illustrates the correctness of the proposed peak clamping type carrier discontinuous pulse width modulation; simulation and experiment show that the invention can use simpler expression to realize the modulation of the discontinuous pulse width of the carrier wave.
The embodiments are only for illustrating the technical idea of the present invention, and the technical idea of the present invention is not limited thereto, and any modifications made on the basis of the technical scheme according to the technical idea of the present invention fall within the scope of the present invention.
Claims (2)
1. The zero-crossing clamping type carrier interrupted pulse width modulation method is characterized in that a zero-sequence component expression needing to be injected is obtained through calculation according to the magnitude relation between three-phase sine modulation waves, and the method is characterized in that: the per-unit three-phase sine modulation wave is shown as formula I, wherein f is the frequency of the power grid; m is the amplitude of the normalized modulation wave, the value of the amplitude is the same as the modulation ratio, and the amplitude is calculated by a formula II;
wherein U isacIs an effective value of the phase voltage of the AC power grid, UdcIs the dc side voltage. By injecting zero sequence components into the three-phase sinusoidal modulation wave, DPWM can be realized by carrier waves. Zero-sequence component u to be injected for zero-crossing clamping type carrier discontinuous pulse width modulationoffset1Calculating according to formula III;
uoffset1＝(0.5-0.5sign(umid))×(1-urmax)-(0.5+0.5sign(umid))×urminformula III
In the formula umidIs the median value of the three-phase sine modulated wave in formula I, sign (u)mid) The function is a sign-taking function when umidWhen the value of (d) is greater than 0, sign (u)mid) The output value is 1; when u ismidWhen the value of (d) is less than 0, sign (u)mid) The output value is-1; u. ofrmaxIs urxMaximum value of (1), urminIs urxMinimum value of (1), urx(x ═ a, b, c) calculated from formula IV;
urx＝umx+0.5-0.5sign(umx) Wherein x is a, b, c formula IV
Calculating the three-phase sine modulation wave after the zero-sequence component is injected according to a formula V;
in the formula uref_xAnd (x ═ a, b and c) are three-phase sine modulation waves of zero-crossing clamped carrier discontinuous pulse width modulation.
2. The peak value clamping type carrier interrupted pulse width modulation is carried out, and a zero sequence component expression required to be injected is obtained through calculation according to the magnitude relation between three-phase sine modulation waves, and the method is characterized in that: clamping the input current maximum phase, its zero-sequence component u to be injectedoffset2Calculated from formula VI;
umaxand uminInjecting zero sequence component u for the maximum and minimum of three-phase sine wave in formula Ioffset2Calculating the later three-phase sine modulation wave according to a formula VII;
in the formula uref_xAnd (x ═ a, b and c) are three-phase sine modulation waves of peak clamping type carrier discontinuous pulse width modulation respectively.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115864798A (en) * | 2022-12-06 | 2023-03-28 | 安徽大学 | Three-level converter carrier DPWM (digital pulse Width modulation) method |
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| US6031738A (en) * | 1998-06-16 | 2000-02-29 | Wisconsin Alumni Research Foundation | DC bus voltage balancing and control in multilevel inverters |
| CN103532410A (en) * | 2013-10-28 | 2014-01-22 | 中国矿业大学 | Low switching loss control method for three-level rectifier |
| CN104702133A (en) * | 2015-02-10 | 2015-06-10 | 北京信息科技大学 | Current tracking control method |
| CN109495001A (en) * | 2018-12-28 | 2019-03-19 | 山东大学 | Three level Vienna rectifier of modular parallel, control system and method |
| CN113098304A (en) * | 2021-05-19 | 2021-07-09 | 河海大学 | Control circuit of three-phase Vienna rectifier and mixed carrier modulation method thereof |
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6031738A (en) * | 1998-06-16 | 2000-02-29 | Wisconsin Alumni Research Foundation | DC bus voltage balancing and control in multilevel inverters |
| CN103532410A (en) * | 2013-10-28 | 2014-01-22 | 中国矿业大学 | Low switching loss control method for three-level rectifier |
| CN104702133A (en) * | 2015-02-10 | 2015-06-10 | 北京信息科技大学 | Current tracking control method |
| CN109495001A (en) * | 2018-12-28 | 2019-03-19 | 山东大学 | Three level Vienna rectifier of modular parallel, control system and method |
| CN113098304A (en) * | 2021-05-19 | 2021-07-09 | 河海大学 | Control circuit of three-phase Vienna rectifier and mixed carrier modulation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 邹宇航;张犁;赵瑞;邢岩: "三相Vienna整流器的不连续空间矢量脉宽调制及电压谐波分析方法", 中国电机工程学报, vol. 40, no. 024 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115864798A (en) * | 2022-12-06 | 2023-03-28 | 安徽大学 | Three-level converter carrier DPWM (digital pulse Width modulation) method |
| CN115864798B (en) * | 2022-12-06 | 2023-07-07 | 安徽大学 | Three-level converter carrier DPWM (digital pulse Width modulation) method |
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