CN106026746A - Nonadjacent mode switching control method for three-phase inverters - Google Patents

Abstract

The invention discloses a nonadjacent mode switching control method for three-phase inverters. The nonadjacent mode switching control method comprises the following steps: A, according to the phase angles of output voltage space vectors of the inverters, determining working sectors where the output voltage space vectors are; B, selecting two nonadjacent working modes of corresponding three-phase inverters according to the working sectors; C, calculating to obtain the working time of each working mode; D, switching the two selected working modes, and synthetising the output voltage space vectors; and E, rotating the output voltage space vectors according to a circular trace to obtain three-phase sine voltage output. The switching frequency of an inverter power tube is reduced to the minimum extent by selecting a corresponding switching sequence based on nonadjacent working modes, so that the switching loss is effectively reduced, and the system efficiency is improved.

Description

A kind of non-adjacent mode switched control method of three-phase inverter

Technical field

The present invention relates to electric energy conversion applied technical field, particularly relate to the non-phase of a kind of three-phase inverter Adjacent mode switched control method.

Background technology

Three-phase inverter, as power electronic equipment indispensable in commercial Application, is widely used in electricity The fields such as Force system, bullet train, electric automobile, large-scale uninterrupted power source (UPS), generation of electricity by new energy. But, along with the increase of three-phase inverter power, and the raising of the switching frequency of power switch pipe, The switching loss of switching tube is increasing, it has also become a pass of restriction high power density inverter development Key problem.

SVPWM is the most conventional control strategy, and it is compared with traditional sine pulse width modulation (PWM) strategy, The harmonic component of output current wave is little, and the utilization rate of DC bus-bar voltage is higher, it is easier to numeral Change and control.But SVPWM needs by realizing the switching of 6 adjacent mode to inverter Controlling, switching frequency is higher and loss is bigger.

Therefore, prior art need development.

Summary of the invention

In place of above-mentioned the deficiencies in the prior art, it is an object of the invention to provide a kind of three-phase inversion The non-adjacent mode switched control method of device, it is intended to solve the switch lock of existing SVPWM control strategy Rate is higher, and bigger problem is lost.

In order to achieve the above object, this invention takes techniques below scheme:

A kind of non-adjacent mode switched control method of three-phase inverter, wherein, including:

A, phase angle according to the output voltage space vector of inverter, determine that described output voltage space is vowed The work sector at amount place；

B, according to described work sector, select corresponding three-phase inverter, 2 non-adjacent work Mode；

C, the working time of the calculating each operation mode of acquisition；

D, switch 2 operation modes of described selection, synthesize described output voltage space vector；

E, by described output voltage space vector by circular trace rotate, it is thus achieved that three phase sine line voltage is defeated Go out.

The non-adjacent mode switched control method of described three-phase inverter, wherein, described operation mode bag Include 6 different operation modes in addition to zero vector；

Described work sector includes 6 different work sectors, and the angle of each work sector is 60 °, Be respectively 0-60 ° first work sector, 60-120 ° second work sector, the 3rd of 120-180 ° the Work sector, 180-240 ° the 4th work sector, 240-300 ° the 5th work sector and The 6th work sector of 300-360 °.

The non-adjacent mode switched control method of described three-phase inverter, wherein, described output voltage is empty Between vector when being positioned at described first work sector, the first operation mode and the second operation mode synthesize；

When described output voltage space vector is positioned at described second work sector, by the second operation mode and the Three operation mode synthesis；

When described output voltage space vector is positioned at described 3rd work sector, by the 3rd operation mode and the Four operation mode synthesis；

When described output voltage space vector is positioned at described 4th work sector, by the 4th operation mode and the Five operation mode synthesis；

When described output voltage space vector is positioned at described 5th work sector, by the 5th operation mode and the Six operation mode synthesis；

When described output voltage space vector is positioned at described 6th work sector, by the 6th operation mode and the One operation mode synthesis.

The non-adjacent mode switched control method of described three-phase inverter, wherein, in step C, when When output voltage vector is positioned at the first work sector, there is a following formula:

$\left[\begin{array}{c}{U}_{\mathrm{\α}}\\ U_{\mathrm{\β}}\end{array}\right]T_s=U_{ref}\left[\begin{array}{c}cos\mathrm{\θ}\\ sin\mathrm{\θ}\end{array}\right]T_s=\frac{2}{3}{U}_{dc}\left[\begin{array}{c}1\\ 0\end{array}\right]T_{100}+\frac{2}{3}{U}_{dc}\left[\begin{array}{c}-cos\frac{\mathrm{\π}}{3}\\ sin\frac{2\mathrm{\π}}{3}\end{array}\right]T_{010}$

Wherein, U_dcFor three-phase inverter DC bus-bar voltage, U_refFor output voltage vector, U_αAnd U_βPoint Biao Shi output voltage vector component on the biphase coordinate axes of static coordinate alpha-beta；T₀₀₀It is the first work When mode and the second operation mode do not work, the time that under inverter, brachium pontis switching tube turns on entirely；T₁₁₁For When first operation mode and the second operation mode do not work, on inverter brachium pontis switching tube entirely turn on time Between；T₁₀₀It it is the working time of the first operation mode；T₀₁₀It it is the working time of the second operation mode；

By above-mentioned formula, can calculate and determine the working time of the first operation mode, the second operation mode Working time and inverter under time of entirely turning on of brachium pontis switching tube.

The non-adjacent mode switched control method of described three-phase inverter, wherein, in step, logical Cross the calculating of following formula and determine described work sector；

$N=sign\left(U_{\mathrm{\β}}\right)+2\×sign(sin\frac{\mathrm{\π}}{3}{U}_{\mathrm{\α}}-sin\frac{\mathrm{\π}}{6}{U}_{\mathrm{\β}})+4\×sign(-sin\frac{\mathrm{\π}}{3}{U}_{\mathrm{\α}}-sin\frac{\mathrm{\π}}{6}{U}_{\mathrm{\β}})$

Wherein, U_αAnd U_βRepresent that output voltage vector is on the biphase coordinate axes of static coordinate alpha-beta respectively Component.

The non-adjacent mode switched control method of described three-phase inverter, wherein, as N=1, institute State output voltage vector and be positioned at the second work sector that angle is 60-120 °；As N=2, described defeated Go out voltage vector and be positioned at the 6th work sector that angle is 300-360 °；As N=3, described output electricity Pressure vector is positioned at the first work sector that angle is 0-60 °；As N=4, described output voltage vector It is positioned at the 4th work sector that angle is 240-300 °；As N=5, described output voltage vector is positioned at Angle is the 3rd work sector of 120-180 °；As N=6, described output voltage vector is positioned at angle For the 5th work sector of 180-240 °.

Beneficial effect: the non-adjacent mode switched control method of the three-phase inverter that the present invention provides is logical Cross to three-phase inverter 6 combinations that operation mode is different in different operating sector to control, it is thus achieved that Sinusoidal line voltage exports.Select corresponding based on non-adjacent operation mode switching sequence so that inversion The on-off times of device power tube is minimum.In same carrier frequencies and in the case of exporting identical sinusoidal line voltage, Compared with SVPWM control mode, power tube on-off times can reduce 2/3, thus effectively reduce and open Close loss thus improve system effectiveness.

Accompanying drawing explanation

Fig. 1 is the work sector schematic diagram of the output voltage vector of the specific embodiment of the invention.

Fig. 2 is the circuit topology figure of three-phase three-wire system inverter.

Fig. 3 is the method flow diagram of the non-adjacent mode switched control method of the specific embodiment of the invention.

Fig. 4 is the synthesis schematic diagram of the output voltage vector of each work sector of the specific embodiment of the invention.

Fig. 5 is the switching sequence schematic diagram of the operation mode of the specific embodiment of the invention.

Fig. 6 is the output voltage waveforms of the non-adjacent mode switched control method of the specific embodiment of the invention Figure.

Fig. 7 is the operation mode switching sequence schematic diagram in employing SVPWM policy control sector 1.

Detailed description of the invention

The present invention provides a kind of non-adjacent mode switched control method of three-phase inverter.For making the present invention Purpose, technical scheme and effect clearer, clear and definite, the embodiment that develops simultaneously referring to the drawings to this Invention further describes.Should be appreciated that specific embodiment described herein is only in order to explain this Invention, is not intended to limit the present invention.

As in figure 2 it is shown, be the circuit topology figure of three-phase three-wire system inverter.The three-phase brachium pontis bag of inverter Including 6 switching tubes, what it was the most possible is combined as 8, including 6 operation modes and two Individual zero vector.

The switching tube state of concrete operation mode and correspondence thereof is as shown in the table:

Easy, below with U for statement₁₀₀, U₁₁₀,U₀₁₀,U₀₁₁, U₀₀₁And U₁₀₁Represent corresponding respectively Operation mode, as it is shown in figure 1, be 6 work sectors of 6 operation modes of the present invention and correspondence The relation of (respectively sector 1-sector 6).Below with above-mentioned 6 operation modes and work sector pair Control method of the present invention is specifically addressed.

As it is shown on figure 3, for the non-adjacent Mode-switch of the three-phase inverter described in the specific embodiment of the invention Control method.Described method comprises the steps:

S100, phase angle according to the output voltage space vector of inverter, determine described output voltage space The work sector at vector place.If the output voltage space vector of inverter is U_ref(vector includes amplitude And phase angle), the work sector at place can be determined according to phase angle.

Concrete, calculated by following formula and determine described work sector, U_αAnd U_βRepresent output respectively Voltage vector component on the biphase coordinate axes of static coordinate alpha-beta.

$N=sign\left(U_{\mathrm{\β}}\right)+2\×sign(sin\frac{\mathrm{\π}}{3}{U}_{\mathrm{\α}}-sin\frac{\mathrm{\π}}{6}{U}_{\mathrm{\β}})+4\×sign(-sin\frac{\mathrm{\π}}{3}{U}_{\mathrm{\α}}-sin\frac{\mathrm{\π}}{6}{U}_{\mathrm{\β}})$

Wherein, as N=1, described output voltage vector is positioned at the second work fan that angle is 60-120 ° District (corresponds to the sector 2 in Fig. 2)；As N=2, described output voltage vector is positioned at angle and is 6th work sector (corresponding to the sector 6 in Fig. 2) of 300-360 °；As N=3, described output Voltage vector is positioned at the first work sector (sector 1 corresponding in Fig. 2) that angle is 0-60 °；When During N=4, described output voltage vector is positioned at the 4th work sector that angle is 240-300 ° and (corresponds to Sector 4 in Fig. 2)；As N=5, it is 120-180 ° that described output voltage vector is positioned at angle 3rd work sector (corresponding to the sector 3 in Fig. 2)；As N=6, described output voltage vector position In the 5th work sector (corresponding to the sector 5 in Fig. 2) that angle is 180-240 °.

S200, according to described work sector, select corresponding three-phase inverter, 2 non-adjacent works Make mode.Concrete, as shown in Figure 4, when output voltage vector is positioned at sector 1, it exports electricity Pressure vector is by operation mode U₁₀₀With U₀₁₀Combination is constituted.When output voltage vector is positioned at sector 2, its Output voltage vector is by operation mode U₁₁₀With U₀₁₁Combination is constituted.When output voltage vector is positioned at sector 3, its output voltage vector is by operation mode U₀₁₀With U₀₀₁Combination is constituted.When output voltage vector position When sector 4, its output voltage vector is by operation mode U₀₁₁With U₁₀₁Combination is constituted.When output electricity When pressure vector is positioned at sector 5, its output voltage vector is by operation mode U₀₀₁With U₁₀₀Combination is constituted. When output voltage vector is positioned at sector 6, its output voltage vector is by operation mode U₁₀₁With U₁₁₀Group Close and constitute.

S300, the working time of the calculating each operation mode of acquisition.After determining the operation mode of synthesis, need Calculate the working time determining each operation mode, with output voltage vector U_refAs a example by sector 1, Its circular is as follows:

When output voltage vector U_refWhen sector 1, output voltage vector is by mode U₁₀₀With mode U₀₁₀Close Become, then have U_refT_s=U₁₀₀T₁₀₀+U₀₁₀T₀₁₀, wherein T₁₀₀It is mode U₁₀₀Working time；T₀₁₀It is mode U₀₁₀ Working time, and have T_s=T₁₀₀+T₀₁₀+T₀₀₀Or T_s=T₁₀₀+T₀₁₀+T₁₁₁, T₀₀₀It is mode U₁₀₀、U₀₁₀No During work, the time that under inverter, brachium pontis switching tube turns on entirely, T₁₁₁It is mode U₁₀₀、U₀₁₀When not working, The time that on inverter, brachium pontis switching tube turns on entirely.If U_refIt is θ with the angle of α axle, inverter direct current Busbar voltage is U_dcThen have:

$\left[\begin{array}{c}{U}_{\mathrm{\α}}\\ U_{\mathrm{\β}}\end{array}\right]T_s=U_{ref}\left[\begin{array}{c}cos\mathrm{\θ}\\ sin\mathrm{\θ}\end{array}\right]T_s=\frac{2}{3}{U}_{dc}\left[\begin{array}{c}1\\ 0\end{array}\right]T_{100}+\frac{2}{3}{U}_{dc}\left[\begin{array}{c}-cos\frac{\mathrm{\π}}{3}\\ sin\frac{2\mathrm{\π}}{3}\end{array}\right]T_{010}$

Mode U is can determine that by above formula₁₀₀、U₀₁₀Working time and inverter under brachium pontis switching tube entirely turn on Time T₀₀₀As follows:

$\left\{\begin{array}{c}{T}_{100}=\sqrt{3}\frac{T_s}{U_{dc}}(\frac{\sqrt{3}}{2}{U}_{\mathrm{\α}}+\frac{1}{2}{U}_{\mathrm{\β}})\\ T_{010}=\sqrt{3}{T}_s\frac{U_{\mathrm{\β}}}{U_{dc}}\\ T_{000}=T_s-T_{100}-T_{010}\end{array}\right.$

In formula,For switching control ratio.

Similarly, when output voltage vector is in sector 2, the specific works time of its operation mode is:

$\left\{\begin{array}{c}{T}_{110}=\sqrt{3}{T}_s\frac{U_{\mathrm{\β}}}{U_{dc}}\\ T_{011}=\sqrt{3}\frac{T_s}{U_{dc}}(\frac{1}{2}{U}_{\mathrm{\β}}-\frac{\sqrt{3}}{2}{U}_{\mathrm{\α}})\\ T_{111}=T_s-T_{110}-T_{011}\end{array}\right.$

Wherein, T₁₁₀And T₀₁₁It is respectively operation mode U₁₁₀And U₀₁₁Working time.

When output voltage vector is in sector 3, the specific works time of its operation mode is:

$\left\{\begin{array}{c}{T}_{010}=\sqrt{3}\frac{T_s}{U_{dc}}(\frac{1}{2}{U}_{\mathrm{\β}}+\frac{\sqrt{3}}{2}{U}_{\mathrm{\α}})\\ T_{001}=\sqrt{3}\frac{T_s}{U_{dc}}(-\frac{\sqrt{3}}{2}{U}_{\mathrm{\α}}-\frac{1}{2}{U}_{\mathrm{\β}})\\ T_{000}=T_s-T_{010}-T_{101}\end{array}\right.$

Wherein, T₀₁₀And T₀₀₁It is respectively operation mode U₀₁₀And U₀₀₁Working time.

When output voltage vector is in sector 4, the specific works time of its operation mode is:

$\left\{\begin{array}{c}{T}_{011}=\sqrt{3}\frac{T_s}{U_{dc}}(-\frac{1}{2}{U}_{\mathrm{\β}}-\frac{\sqrt{3}}{2}{U}_{\mathrm{\α}})\\ T_{101}=-\sqrt{3}{T}_s\frac{U_{\mathrm{\β}}}{U_{dc}}\\ T_{111}=T_s-T_{011}-T_{101}\end{array}\right.$

Wherein, T₀₁₁And T₁₀₁It is respectively operation mode U₀₁₁And U₁₀₁Working time.

When output voltage vector is in sector 5, the specific works time of its operation mode is:

$\left\{\begin{array}{c}{T}_{001}=-\sqrt{3}\frac{T_s}{U_{dc}}{U}_{\mathrm{\β}}\\ T_{100}=\sqrt{3}\frac{T_s}{U_{dc}}(\frac{\sqrt{3}}{2}{U}_{\mathrm{\α}}-\frac{1}{2}{U}_{\mathrm{\β}})\\ T_{000}=T_s-T_{001}-T_{100}\end{array}\right.$

Wherein, T₀₀₁And T₁₀₀It is respectively operation mode U₀₀₁And U₁₀₀Working time.

And when output voltage vector is in sector 6, the specific works time of its operation mode is:

$\left\{\begin{array}{c}{T}_{101}=\sqrt{3}\frac{T_s}{U_{dc}}(\frac{\sqrt{3}}{2}{U}_{\mathrm{\α}}-\frac{1}{2}{U}_{\mathrm{\β}})\\ T_{110}=\sqrt{3}\frac{T_s}{U_{dc}}(\frac{\sqrt{3}}{2}{U}_{\mathrm{\α}}+\frac{1}{2}{U}_{\mathrm{\β}})\\ T_{111}=T_s-T_{101}-T_{110}\end{array}\right.$

Wherein, T₁₀₁And T₁₁₀It is respectively operation mode U₁₀₁And U₁₁₀Working time.

S400, switch 2 operation modes of described selection, synthesize described output voltage space vector.As Shown in Fig. 5, for above-mentioned 6 work sectors and the schematic diagram of the concrete switching mode of operation mode.With Output voltage space vector is described in detail as a example by sector 1:

Mode U when current period starts₁₀₀In running order, allow mode U₁₀₀Continuous firing T₁₀₀Time is extremely Shown in Fig. 5 (H), a point, is then switched to zero vector, and zero vector continues T₀₀₀Time is to Fig. 5 (H) Shown b point, is then switched to mode U₀₁₀, mode U₀₁₀Worked T₀₁₀This end cycle after time.

It is apparent that in order to reduce on-off times, relief mode U can be started in second round₀₁₀Continue work Make to T second round₀₁₀Time terminates, i.e. c point shown in Fig. 5 (H).Zero vector is switched at c point Until the T of second round₀₀₀Time terminates, i.e. d point shown in Fig. 5 (H), finally switches at d point Mode U₁₀₀And work to second round and terminate.

When being positioned at other sectors, the concrete switching mode such as Fig. 5 (J) of its operation mode-(M) institute Showing, its concrete analysis is similar with sector 1, and therefore not to repeat here.

S500, by described output voltage space vector by circular trace rotate, it is thus achieved that three as shown in Figure 6 Phase sinusoidal line voltage exports.

As shown in s1 and s2 in Fig. 5 (H), non-adjacent operation mode of the present invention is used to cut Changing the three-phase inverter that control method controls, in inverter upper and lower bridge arm, 2 power tubes are a job Cycle respectively switchs 1 time, totally 2 times.And if as it is shown in fig. 7, use SVPWM control time, inversion In device upper and lower bridge arm, 6 power tubes respectively switch 1 time, totally 6 times, therefore identical carrier frequency with And in the case of identical line voltage output, non-adjacent mode switched control is compared SVPWM and is controlled it and open Close frequency and reduce 2/3, it is possible to effectively reduce switching loss thus improve system effectiveness.

It is understood that for those of ordinary skills, can be according to the technology of the present invention Scheme and present inventive concept in addition equivalent or change, and all these change or replace all should belong to The protection domain of appended claims of the invention.

Claims (6)

1. the non-adjacent mode switched control method of a three-phase inverter, it is characterised in that including:

A, phase angle according to the output voltage space vector of inverter, determine that described output voltage space is vowed The work sector at amount place；

B, according to described work sector, select corresponding three-phase inverter, 2 non-adjacent work Mode；

C, the working time of the calculating each operation mode of acquisition；

D, switch 2 operation modes of described selection, synthesize described output voltage space vector；

E, by described output voltage space vector by circular trace rotate, it is thus achieved that three phase sine line voltage is defeated Go out.

The non-adjacent mode switched control method of three-phase inverter the most according to claim 1, its Being characterised by, described operation mode includes 6 different operation modes in addition to zero vector；

Described work sector includes 6 different work sectors, and the angle of each work sector is 60 °, Be respectively 0-60 ° first work sector, 60-120 ° second work sector, the 3rd of 120-180 ° the Work sector, 180-240 ° the 4th work sector, 240-300 ° the 5th work sector and The 6th work sector of 300-360 °.

The non-adjacent mode switched control method of three-phase inverter the most according to claim 2, its It is characterised by, when described output voltage space vector is positioned at described first work sector, by the first work Mode and the synthesis of the second operation mode；

When described output voltage space vector is positioned at described second work sector, by the second operation mode and the Three operation mode synthesis；

When described output voltage space vector is positioned at described 3rd work sector, by the 3rd operation mode and the Four operation mode synthesis；

When described output voltage space vector is positioned at described 4th work sector, by the 4th operation mode and the Five operation mode synthesis；

When described output voltage space vector is positioned at described 5th work sector, by the 5th operation mode and the Six operation mode synthesis；

When described output voltage space vector is positioned at described 6th work sector, by the 6th operation mode and the One operation mode synthesis.

The non-adjacent mode switched control method of three-phase inverter the most according to claim 3, its It is characterised by, in step C, when output voltage vector is positioned at the first work sector, having following calculation Formula:

$\left[\begin{array}{c}{U}_{\mathrm{\α}}\\ U_{\mathrm{\β}}\end{array}\right]T_s=U_{ref}\left[\begin{array}{c}cos\mathrm{\θ}\\ sin\mathrm{\θ}\end{array}\right]T_s=\frac{2}{3}{U}_{dc}\left[\begin{array}{c}1\\ 0\end{array}\right]T_{100}+\frac{2}{3}{U}_{dc}\left[\begin{array}{c}-cos\frac{\mathrm{\π}}{3}\\ sin\frac{2\mathrm{\π}}{3}\end{array}\right]T_{010}$

Wherein, U_dcFor three-phase inverter DC bus-bar voltage, U_refFor output voltage vector, U_αAnd U_βPoint Biao Shi output voltage vector component on the biphase coordinate axes of static coordinate alpha-beta；T₀₀₀It is the first work When mode and the second operation mode do not work, the time that under inverter, brachium pontis switching tube turns on entirely；T₁₁₁For When first operation mode and the second operation mode do not work, on inverter brachium pontis switching tube entirely turn on time Between；T₁₀₀It it is the working time of the first operation mode；T₀₁₀It it is the working time of the second operation mode；

By above-mentioned formula, can calculate and determine the working time of the first operation mode, the second operation mode Working time and inverter under time of entirely turning on of brachium pontis switching tube.

The non-adjacent mode switched control method of three-phase inverter the most according to claim 1, its It is characterised by, in step, is calculated by following formula and determine described work sector；

$N=sign\left(U_{\mathrm{\β}}\right)+2\×sign(sin\frac{\mathrm{\π}}{3}{U}_{\mathrm{\α}}-sin\frac{\mathrm{\π}}{6}{U}_{\mathrm{\β}})+4\×sign(-sin\frac{\mathrm{\π}}{3}{U}_{\mathrm{\α}}-sin\frac{\mathrm{\π}}{6}{U}_{\mathrm{\β}})$

Wherein, U_αAnd U_βRepresent that output voltage vector is on the biphase coordinate axes of static coordinate alpha-beta respectively Component.

The non-adjacent mode switched control method of three-phase inverter the most according to claim 5, its Being characterised by, as N=1, described output voltage vector is positioned at the second work that angle is 60-120 ° Sector；As N=2, described output voltage vector is positioned at the 6th work sector that angle is 300-360 °； As N=3, described output voltage vector is positioned at the first work sector that angle is 0-60 °；Work as N=4 Time, described output voltage vector is positioned at the 4th work sector that angle is 240-300 °；As N=5, Described output voltage vector is positioned at the 3rd work sector that angle is 120-180 °；As N=6, described Output voltage vector is positioned at the 5th work sector that angle is 180-240 °.