CN106452128B - Control method and device for solving space vector pulse width modulation current zero-crossing point distortion - Google Patents
Control method and device for solving space vector pulse width modulation current zero-crossing point distortion Download PDFInfo
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- CN106452128B CN106452128B CN201610929673.4A CN201610929673A CN106452128B CN 106452128 B CN106452128 B CN 106452128B CN 201610929673 A CN201610929673 A CN 201610929673A CN 106452128 B CN106452128 B CN 106452128B
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Classifications
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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
- H02M7/2173—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 in a biphase or polyphase circuit arrangement
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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
- H02M1/00—Details of apparatus for conversion
- H02M1/0003—Details of control, feedback or regulation circuits
- H02M1/0038—Circuits or arrangements for suppressing, e.g. by masking incorrect turn-on or turn-off signals, e.g. due to current spikes in current mode control
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Abstract
本发明涉及解决空间矢量脉宽调制电流过零点畸变的控制方法和装置，首先采集各相的相电压；然后判断相电压穿越零点时是正向过零还是负向过零，当相电压正向过零时，正、负载波切换点设置在COMP～PRD；当相电压负向过零时，正、负载波切换点设置在0～COMP。通过这种方法能够有效增大切换点开关管导通时间，以此减小过零点占空比的突变，从而减小过零点电流畸变。并且，该方法控制过程较为简单，降低了控制复杂度，提升了控制可靠性。
The invention relates to a control method and device for solving the distortion of space vector pulse width modulation current zero-crossing point. First, the phase voltage of each phase is collected; When it is zero, the switching point between positive and load waves is set at COMP~PRD; when the phase voltage crosses zero in the negative direction, the switching point between positive and load waves is set at 0~COMP. This method can effectively increase the on-time of the switch at the switching point, thereby reducing the sudden change of the duty cycle at the zero-crossing point, thereby reducing the current distortion at the zero-crossing point. Moreover, the control process of the method is relatively simple, the control complexity is reduced, and the control reliability is improved.
Description
Technical field
The present invention relates to the control methods and device that solve the distortion of space vector pulse width modulation current zero-crossing point.
Background technique
In three-phase rectifier control system, it is more general that vector sends out wave mode (i.e. space vector pulse width modulation mode, SVPWM)
Tong Fabo mode has small inductive current ripple, rapid dynamic response speed and high reliability, therefore is widely used；Vector
Hair wave property determines that ac phase voltage switches positive and negative triangular carrier when passing through zero point, and triangular carrier moves right 180 ° of phases at this time
Parallactic angle causes the PWM duty cycle of 1.5 times of switch periods to be mutated, leads to current distortion, the voltage ride-through zero point of any phase
The phase current zero cross distortion occurs for Shi Douhui, while influencing other two-phases, and three-phase current influences each other, and causes repeatedly humorous
Wave causes harmonic pollution to power grid.
Current zero-crossing point distortion is the intrinsic problem based on vector hair wave mode three-phase rectifier, but current zero-crossing point distorts
Degree depends on the switching point of positive and negative carrier wave, and switching point difference causes duty ratio distortion different, when input voltage passes through zero point
When, input voltage is close to zero, and current sinusoidal wave has rising greatest gradient herein, so inductance both ends need maximum volt
Second product moment, switching tube duty ratio is close to 1, so to make the PWM duty of 1.5 times of switch periods when selection carrier switch point as far as possible
Than remaining 1, the duty ratio mutation of zero crossing thus can reduce, and then reduce current distortion.
Two kinds are broadly divided into based on the current zero-crossing point aberration control research of vector hair wave to three-phase rectifier both at home and abroad: soft
Part control and hardware circuit control.Software control, which mainly passes through, adjusts current loop parameter, keeps electric current loop as fast as possible, is disappeared with this
Except current distortion, this method needs to weigh system stability and reliability；Hardware approach, which mainly passes through, increases the sense of PFC inductance
Amount, current distortion can be reduced by increasing sensibility reciprocal, but entire control system mathematical model changes after inductance variation, software control
Parameter need to adjust again, more complicated.
Summary of the invention
The object of the present invention is to provide a kind of control methods of solution space vector pulse width modulation current zero-crossing point distortion, use
It is more complicated with the control method for solving current zero-crossing point distortion for solving the problems, such as traditional.Present invention simultaneously provides a kind of solutions
The control device of space vector pulse width modulation current zero-crossing point distortion.
To achieve the above object, the solution of the present invention includes: that a kind of solution space vector pulse width modulation current zero-crossing point is abnormal
The control method of change, comprising the following steps:
(1) phase voltage of each phase is acquired；
(2) judge when phase voltage passes through zero point it is positive going zeror crossing or negative sense zero passage, when phase voltage positive going zeror crossing, just,
Negative carrier switching point is arranged in COMP~PRD；When phase voltage negative sense zero passage, positive and negative carrier switch point is arranged in 0~COMP.
A phase voltage Va forward direction passes through the Rule of judgment of zero point are as follows: Va instantaneous value is close to zero, Vb instantaneous value close to Vm*
Sin60 °, Vc instantaneous value is close to-Vm*sin60 °；B phase voltage Vb forward direction passes through the Rule of judgment of zero point are as follows: Vb instantaneous value is close
Zero, Vc instantaneous value are close to Vm*sin60 °, and Va instantaneous value is close to-Vm*sin60 °；C phase voltage Vc forward direction passes through the judgement item of zero point
Part are as follows: Vc instantaneous value is close to zero, Va instantaneous value close to Vm*sin60 °, and Vb instantaneous value is close to-Vm*sin60 °；
The Rule of judgment that A phase voltage Va negative sense passes through zero point is: Va instantaneous value approaches-Vm* close to zero, Vb instantaneous value
Sin60 °, Vc instantaneous value is close to Vm*sin60 °；The Rule of judgment that B phase voltage Vb negative sense passes through zero point is: Vb instantaneous value is close
Zero, Vc instantaneous value are close to-Vm*sin60 °, and Va instantaneous value is close to Vm*sin60 °；C phase voltage Vc negative sense passes through the judgement item of zero point
Part is: Vc instantaneous value is close to zero, Va instantaneous value close to-Vm*sin60 °, and Vb instantaneous value is close to Vm*sin60 °；Wherein Vm is mutually electric
The amplitude of pressure.
Relationship between COMP and PRD is: COMP > 50%PRD.
The COMP=60%PRD.
A kind of control device solving the distortion of space vector pulse width modulation current zero-crossing point, comprising:
Acquisition module, for acquiring the phase voltage of each phase；
Control module is positive going zeror crossing or negative sense zero passage when for judging that phase voltage passes through zero point, when phase voltage forward direction
When zero passage, positive and negative carrier switch point is arranged in COMP~PRD；When phase voltage negative sense zero passage, positive and negative carrier switch point setting
In 0~COMP.
A phase voltage Va forward direction passes through the Rule of judgment of zero point are as follows: Va instantaneous value is close to zero, Vb instantaneous value close to Vm*
Sin60 °, Vc instantaneous value is close to-Vm*sin60 °；B phase voltage Vb forward direction passes through the Rule of judgment of zero point are as follows: Vb instantaneous value is close
Zero, Vc instantaneous value are close to Vm*sin60 °, and Va instantaneous value is close to-Vm*sin60 °；C phase voltage Vc forward direction passes through the judgement item of zero point
Part are as follows: Vc instantaneous value is close to zero, Va instantaneous value close to Vm*sin60 °, and Vb instantaneous value is close to-Vm*sin60 °；
The Rule of judgment that A phase voltage Va negative sense passes through zero point is: Va instantaneous value approaches-Vm* close to zero, Vb instantaneous value
Sin60 °, Vc instantaneous value is close to Vm*sin60 °；The Rule of judgment that B phase voltage Vb negative sense passes through zero point is: Vb instantaneous value is close
Zero, Vc instantaneous value are close to-Vm*sin60 °, and Va instantaneous value is close to Vm*sin60 °；C phase voltage Vc negative sense passes through the judgement item of zero point
Part is: Vc instantaneous value is close to zero, Va instantaneous value close to-Vm*sin60 °, and Vb instantaneous value is close to Vm*sin60 °；Wherein Vm is mutually electric
The amplitude of pressure.
Relationship between COMP and PRD is: COMP > 50%PRD.
The COMP=60%PRD.
It is whole that the control method provided by the invention for solving the distortion of space vector pulse width modulation current zero-crossing point is suitable for three-phase
Device is flowed, acquires the phase voltage of each phase first；It is positive going zeror crossing or negative sense zero passage when then passing through zero point according to phase voltage to set
Fixed positive and negative carrier switch point, when phase voltage positive going zeror crossing, positive and negative carrier switch point is arranged in COMP~PRD；Work as phase voltage
When negative sense zero passage, positive and negative carrier switch point is arranged in 0~COMP, can effectively increase switching point switching tube by this method
Turn-on time, reduces the mutation of zero crossing duty ratio with this, to reduce zero crossing current distortion.Also, this method controlled
Journey is relatively simple, reduces control complexity, improves control reliability.
Moreover, the thinking based on space vector pulse width modulation near zero-crossing point output driving duty ratio close to 1, as long as logical
It crosses and positive and negative carrier switch point is set output driving duty ratio is made to remain 1, so that it may reduce duty ratio mutation, and then reduce
The distortion of zero current.Guarantee that entire three-phase rectifier system makes electricity on the basis of not modifying hardware circuit and control parameter
Zero point is flowed through with lesser distortion, and modification debugging is simple, save the cost, and control effect is good.
Detailed description of the invention
Fig. 1 is three-phase rectifier topology schematic diagram；
Fig. 2 is three-phase alternating current input phase voltage zero-acrross ing moment schematic diagram；
Fig. 3 is switching point setting schematic diagram when positive carrier switches to negative carrier；
Switching point setting schematic diagram when Fig. 4 is load wave direction positive carrier switching.
Specific embodiment
Control method embodiment
As shown in Figure 1, it is a kind of topological diagram of three-phase rectifier provided in this embodiment, inventive point of the invention is
A kind of control method solving the distortion of space vector pulse width modulation (SVPWM) current zero-crossing point, so, the control method not office
The three-phase rectifier being limited in Fig. 1.Moreover, because space vector pulse width modulation (SVPWM) technology belongs to the prior art, at present this
As soon as technology is more mature, then the present embodiment no longer describes SVPWM itself in detail.
As shown in Figure 1, Va, Vb are that three-phase rectifier exchanges input with Vc, the alternating current of input passes through EMI electromagnetism interference
Circuit is handled, and La, Lb and Lc are Boost inductance, and D1-D6 is rectifier diode, and Q1, Q2, Q3, Q4, Q5 and Q6 are rectifications
Device metal-oxide-semiconductor, Vp and Vn are positive and negative bus capacitor respectively.Three-phase alternating current input voltage passes through rectifier diode and metal-oxide-semiconductor, and
The effect of positive and negative busbar capacitor exports DC voltage.
In the present embodiment, control chip using the TMS320F28035 of TI as DSP control system, dominant frequency reaches 60MHz,
The calculating of various digital control algorithms can be quickly completed in real time.By control method provided by the invention with the shape of software program
Formula load in the control chip, realization correspondingly control, i.e., by judging that phase voltage passes through zero point when be positive going zeror crossing or
Negative sense zero passage sets the switching point of positive and negative carrier wave, with this intrinsic problem mistake to three-phase rectifier space vector pulse width modulation
Zero current distortion is controlled.
Firstly, it is necessary to acquire the phase voltage of each phase of three-phase rectifier, and collected information of voltage is inputed into DSP,.
Then, DSP be when judging that each phase voltage passes through zero point according to collected each phase phase voltage positive going zeror crossing or
Negative sense zero passage sets positive and negative carrier switch point with this.It is positive going zeror crossing or negative that a kind of phase voltage, which is given below, and passes through zero point
To the judgment mode of zero passage.
As shown in Fig. 2, A phase voltage Va forward direction passes through the Rule of judgment of zero point are as follows: Va instantaneous value connects close to zero, Vb instantaneous value
Vm*sin60 ° nearly, Vc instantaneous value is close to-Vm*sin60 °；B phase voltage Vb forward direction passes through the Rule of judgment of zero point are as follows: Vb instantaneous value
Close to zero, Vc instantaneous value close to Vm*sin60 °, Va instantaneous value is close to-Vm*sin60 °；C phase voltage Vc forward direction passes through sentencing for zero point
Broken strip part are as follows: Vc instantaneous value is close to zero, Va instantaneous value close to Vm*sin60 °, and Vb instantaneous value is close to-Vm*sin60 °；A phase voltage
The Rule of judgment that Va negative sense passes through zero point is: for Va instantaneous value close to zero, Vb instantaneous value close to-Vm*sin60 °, Vc instantaneous value is close
Vm*sin60°；The Rule of judgment that B phase voltage Vb negative sense passes through zero point is: Vb instantaneous value approaches-Vm* close to zero, Vc instantaneous value
Sin60 °, Va instantaneous value is close to Vm*sin60 °；The Rule of judgment that C phase voltage Vc negative sense passes through zero point is: Vc instantaneous value is close
Zero, Va instantaneous value are close to-Vm*sin60 °, and Vb instantaneous value is close to Vm*sin60 °；Wherein Vm is the amplitude of three-phase alternating current phase voltage.
It is above-mentioned when judging, be correspondingly to be judged using three-phase phase voltage close to some value, in each criterion
" close " can be understood as "Yes", because are as follows: for example, Va instantaneous value is zero, Vb wink when A phase voltage Va forward direction passes through zero point
Duration is Vm*sin60 °, and Vc instantaneous value is-Vm*sin60 °.Others judgement is also such.
As shown in figure 3, when phase voltage positive going zeror crossing, corresponding positive and negative carrier switch point is set for wherein any one phase
It sets in COMP~PRD.Based on space vector pulse width modulation near zero-crossing point thinking of the output driving duty ratio close to 1 simultaneously,
When D duty ratio approach 1, the mutation of duty ratio caused by positive carrier switches to negative carrier is minimum, and then makes phase voltage positive going zeror crossing
When zero crossing current distortion be inhibited.
As shown in figure 4, corresponding positive and negative carrier switch point is arranged in 0~COMP when phase voltage negative sense zero passage.It is based on
Space vector pulse width modulation near zero-crossing point, bear when D duty ratio approach 1 simultaneously by thinking of the output driving duty ratio close to 1
The mutation of duty ratio caused by carrier wave switches to positive carrier is minimum, and then obtains zero crossing current distortion when phase voltage negative sense zero passage
Inhibit.
Wherein, COMP value is carrier wave fiducial value, can be calculated by the control chip in system, can also be directly according to reality
Situation is set, and COMP value, which plays the role of adjusting, opens power pass pipe duty ratio size；COMP value is limited in 0 to PRD value
Between.PRD value is carrier cycle time value, determines that power switch tube working frequency, PRD value are equal to the half of switch periods.And
And by Fig. 3 or Fig. 4 it is found that the relationship between COMP and PRD is: COMP > 50%PRD, the present embodiment further provide two
A kind of physical relationship of person is COMP=60%PRD.
Control device embodiment
In the present embodiment, the control device for solving the distortion of space vector pulse width modulation current zero-crossing point includes two parts: being adopted
Collect module and control module, wherein
Acquisition module is used to acquire the phase voltage of each phase；
Control module is for judging it is positive going zeror crossing or negative sense zero passage when phase voltage passes through zero point, when phase voltage forward direction mistake
When zero, corresponding positive and negative carrier switch point is arranged in COMP~PRD；When phase voltage negative sense zero passage, corresponding positive and negative carrier wave
Switching point is arranged in 0~COMP.
By to above-mentioned two module analysis it is found that the control device is substantially still control method, due to above-mentioned control
The control method is made that in embodiment of the method processed and is described in detail, is just no longer illustrated here.
Specific embodiment is presented above, but the present invention is not limited to described embodiment.Base of the invention
This thinking is above-mentioned basic scheme, and for those of ordinary skill in the art, various changes are designed in introduction according to the present invention
The model of shape, formula, parameter do not need to spend creative work.It is right without departing from the principles and spirit of the present invention
The change, modification, replacement and modification that embodiment carries out are still fallen in protection scope of the present invention.
Claims (8)
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