CN109981025A - A kind of motor control method of irregular carrier wave slope Stochastic Modulation - Google Patents
A kind of motor control method of irregular carrier wave slope Stochastic Modulation Download PDFInfo
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- CN109981025A CN109981025A CN201910235887.5A CN201910235887A CN109981025A CN 109981025 A CN109981025 A CN 109981025A CN 201910235887 A CN201910235887 A CN 201910235887A CN 109981025 A CN109981025 A CN 109981025A
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- carrier wave
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P23/00—Arrangements or methods for the control of AC motors characterised by a control method other than vector control
- H02P23/04—Arrangements or methods for the control of AC motors characterised by a control method other than vector control specially adapted for damping motor oscillations, e.g. for reducing hunting
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P27/00—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage
- H02P27/04—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage
- H02P27/06—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage using dc to ac converters or inverters
- H02P27/08—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage using dc to ac converters or inverters with pulse width modulation
Abstract
The invention discloses a kind of motor control method of irregular carrier wave slope Stochastic Modulation, the method realization includes: four three-phase motor, voltage source inverter bridge, modulating wave generation module, random PWM generation module parts.Wherein random PWM generation module corresponds to the value of stochastic variable in fixed sawtooth carrier wave by comparing irregular carrier wave slope when random, calculate the size of 6 road fiducial values in a cycle, then calculated fiducial value generates random PWM pulse compared with sawtooth carrier wave.The realization of the irregular carrier wave slope Stochastic Modulation method is not necessarily to external add-in circuit, has universality, calculation amount is small, is easy to Project Realization；Phase current frequency spectrum can be uniformly distributed in a wider scope in the case where keeping sample frequency constant, reduce the harmonic amplitude at switching frequency integral multiple, reach inhibition system electromagnetic interference, reduce the purpose of motor high and low frequency vibration.
Description
Technical field
The present invention relates to a kind of motor control methods of irregular carrier wave slope Stochastic Modulation, belong to Motor Control Field.
Background technique
Vibration noise and electromagnetic interference with the high speed development of industry and scientific and technological level, when motor operation
(electromagnetic interference, EMI) has become to be paid close attention to and urgent problem to be solved instantly.Motor frequency conversion
When power supply, pulse width modulation controlled can introduce a large amount of current harmonics in armature winding, so that motor is in switching frequency integral multiple
Place generates apparent vibration noise, can also aggravate EMI of motor, influence the overall performance of Mechatronic Systems.Different motor controls
Method processed, phase current harmonic amplitude size and regularity of distribution difference can inhibit motor oscillating by optimization motor control method
And the problems such as electromagnetic interference.
The problems such as vibration noise and electromagnetic interference for generating when for motor frequency conversion power supply, many spies have been carried out both at home and abroad
It begs for." double random PWM technical research based on vector control system " (see " Proceedings of the CSEE ", 36 phases of volume 30,
2010) a kind of zero vector-change delay random PWM method for proposing fixed sample period can be by current spectrum wider
It is uniformly distributed in range, reduces the harmonic amplitude of integral multiple switching frequency, effectively reduce system noise and inhibit electromagnetic interference, but
Random device random effect in motor high modulation ratio is deteriorated, and only has inhibiting effect to motor high-frequency vibration.A kind of " triangle
Carrier wave slope random distribution pulse duration modulation method " (CN 201610850686.2,2017) proposes that a kind of triangular carrier slope is random
Pulse duration modulation method can effectively disperse to concentrate on the harmonic wave near carrier frequency and its frequency multiplication originally, make originally biggish
Prominent harmonic amplitude greatly reduces, and effectively inhibits the electromagnetic interference problem inside electric system, but the carrier format utilizes outside
Hardware circuit generates, and does not have generality, and sample frequency and carrier frequency synchronization random variations due control system performance.
Summary of the invention
The purpose of the present invention is for electric machine phase current high and low frequency harmonic amplitude under traditional fixed triangle carried based PWM
Greatly, the problems such as causing the biggish high and low frequency vibration of motor and electromagnetic interference, and a kind of irregular carrier wave slope proposed is adjusted at random
The motor control method of system, the method are obvious to the inhibitory effect of motor oscillating, and sample frequency is constant, are easy to engineering reality
It is existing, it is not necessarily to hardware-assist circuit, there is universality.
To realize that the control method, the present invention are realized using system as shown in Figure 1, comprising: three-phase motor, voltage
Source inverter bridge, modulating wave generation module, random PWM generation module.Wherein random PWM generation module exports 6 road PWM to voltage source
Inverter bridge, motor three-phase windings exchange side with voltage source inverter bridge and are connected, and instruct Setting signal R*With feedback signal ia、ib, θ make
It is connected for input with modulating wave generation module, modulating wave generation module exports modulating wave Ta、Tb、TcIt is produced as random PWM is input to
Raw module.For the control instruction R of modulating wave generation module*Can be revolving speed n, torque T, position θ, frequency f signal, it is different
Control instruction corresponds to different motor control methods.
For random PWM generation module, comprising: random carrier modulation block, fiducial value computing module, PWM modulation module.
Wherein, random carrier modulation block modulation generates carrier amplitude 2TR and stochastic variable TM and is given to fiducial value computing module, PWM
Modulation module is as input, 3 road modulating wave Ta、Tb、TcAnd 2TR, TM through fiducial value computing module output fiducial value cva1, cva2,
Cva3, cvb1, cvb2, cvb3 and with 2TR, TM collectively as the input of PWM modulation module, PWM modulation module exports PWM conduct
The input of voltage source inverter bridge.
Wherein, irregular random carrier wave is a kind of both sides slope k in the random carrier modulation block1、k2Random variation,
But cycle TsConstant asymmetric triangular carrier, slope k1、k2With carrier cycle Ts, relationship between carrier amplitude TR are as follows:
β indicates the ratio of irregular carrier wave vertex correspondence time and carrier cycle in formula, and value range is [0,1],
The asymmetric degree of indirect reaction carrier wave.
Construct amplitude be 2TR, period TsSawtooth carrier wave, two kinds of carrier formats are compared, when irregular carrier wave slope k1、
k2When random variation, β value also corresponding random variation, the corresponding random variation for causing variable TM in fixed sawtooth carrier wave, therefore use width
Value is 2TR, period TsSawtooth carrier wave in variable TM random variation characterization amplitude be TR, period TsIrregular carrier wave
Slope k1、k2Random variation, wherein TM and k1Between relational expression are as follows:
Variable TM is by k in formula1It determines, and k1It is determined by variable β, so the random variation of β corresponds in fixed sawtooth carrier wave
For the random variation of variable TM, and variable TM value range is [0,2TR].
The fiducial value computing module passes through input variable Ta、Tb、Tc, 2TR, TM calculate each fixed sawtooth carrier wave period
TsIn 6 fiducial values size, calculation method are as follows:
R in formulaa(t)、rb(t)、rc(t) indicate that the modulating wave of 120 ° of 3 road mutual deviation, waveform are saddle wave.
The PWM modulation module is T using the periods, amplitude is the fixation sawtooth carrier wave of 2TR compared with 6 fiducial values, is produced
The raw asymmetric random PWM pulse in 3 tunnels, remaining 3 tunnel complementary output, finally using 6 road PWM be given to voltage source inverter bridge as input from
And control three-phase motor.
The present invention is compared with existing Random PWM Technique, the advantage is that: only needing a stochastic variable that can play
A variety of random effects such as random zero vector, Randomized Pulse Position, random effective voltage vector；Sample frequency is fixed, and no outside is attached
It is powered on road, there is universality；Calculation amount is small, is easy to Project Realization.
The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:
Detailed description of the invention
The motor control method system structure diagram of the irregular carrier wave slope Stochastic Modulation of Fig. 1；
The irregular carrier wave slope of Fig. 2 at random with fixed sawtooth carrier wave comparison schematic diagram.
Specific embodiment
The present invention provides a kind of motor control method of irregular carrier wave slope Stochastic Modulation, makees in conjunction with attached drawing to this method
It is described in further detail.
To realize that the control method, the present invention realize that system mainly includes three-phase electricity using system as shown in Figure 1
Mechanical, electrical potential source inverter bridge, modulating wave generation module, random PWM generation module.Wherein with electric machine phase current ia、ibAnd rotor-position
θ is input to modulating wave generation module as feedback signal, instructs Setting signal R*With feedback signal ia、ib, θ as input be given to tune
Wave generation module processed simultaneously exports 3 road modulating wave Ta、Tb、Tc.The control instruction R of modulating wave generation module*It can be revolving speed n, torque
T, position θ, frequency f signal instruct R*Give the different modulator approach of different corresponding motors.
For random PWM generation module, including random carrier modulation block, fiducial value computing module, PWM modulation module.
Wherein, random carrier modulation block modulation generates carrier amplitude 2TR and stochastic variable TM and is given to fiducial value computing module, PWM
Modulation module is as input, 3 road modulating wave Ta、Tb、TcAnd 2TR, TM through fiducial value computing module output fiducial value cva1, cva2,
Cva3, cvb1, cvb2, cvb3 and with 2TR, TM collectively as the input of PWM modulation module, PWM modulation module exports 6 road PWM
Input as voltage source inverter bridge.
If Fig. 2 is random irregular carrier wave and fixed sawtooth carrier wave schematic diagram, two kinds of carrier waves in random carrier modulation block
Form can be described as, in a cycle TsIt is interior, with slope k1Time β T is begun to pass through from 0sAmplitude increases to TR afterwards, then with slope
k2Start when amplitude is reduced to end cycle to be 0；The sawtooth carrier wave can be described as, in a cycle TsIt is interior, with fixed slope k3
Cycle T is begun to pass through from 0sAmplitude increases to 2TR afterwards, is then instantaneously reduced to 0, wherein fixed sawtooth carrier wave slope k3It can indicate
For fixed sawtooth carrier wave amplitude 2TR and cycle TsRatio, fixed then its carrier wave slope k of sawtooth carrier wave3It remains unchanged；Irregularly
Carrier wave is represented by slope k at random1、k2Random variation, and the relationship of the two indicates are as follows:
Variable β determines irregular carrier wave slope k in above formula1、k2Value size, and the value range of β be [0,1], institute
It is exactly to irregular carrier wave slope k with the STOCHASTIC CONTROL to variable β1、k2STOCHASTIC CONTROL.
In same period, irregular carrier wave slope k1、k2Random variation, it is corresponding to cause variable TM in fixed sawtooth carrier wave
Random variation, TM and k1Between relational expression are as follows:
Variable TM is by k in formula1It determines, and k1It is determined by variable β, so variable TM is determined by β, and its value range is
[0,2TR]。
Fiducial value computing module passes through input variable Ta、Tb、Tc, 2TR, TM calculate each fixed sawtooth carrier wave cycle TsIn 6
The size of a fiducial value, calculation method are as follows:
R in formulaa(t)、rb(t)、rc(t) indicate that the modulating wave of 120 ° of 3 road mutual deviation, waveform are saddle wave.
PWM modulation module is for generating 6 road random PWM pulses, in a control cycle TsInterior, the controller generation period is
Ts, amplitude be 2TR fixation sawtooth carrier wave, then compared with 6 fiducial values, when sawtooth carrier wave value be greater than fiducial value cva1,
When cva2, cva3, pwm pulse becomes high level, when sawtooth carrier wave value is greater than fiducial value cvb1, cvb2, cvb3, pwm pulse
Become low level.Wherein cva1, cvb1 are one group of fiducial value, compare generation PWM all the way, corresponding other two groups of generations two-way PWM,
Remaining 3 tunnel complementary output.
The motor control method of the irregular carrier wave slope Stochastic Modulation, by keeping irregular carrier cycle TsIt is permanent
It is fixed, slope k1、k2Random to change to realize the investigation of random PWM control to motor, the random device can keep sampling
Phase current frequency spectrum is uniformly distributed in a wider scope in the case that frequency is constant, reduces the harmonic wave at switching frequency integral multiple
Amplitude reaches inhibition system electromagnetic interference, reduces the purpose of motor high and low frequency vibration.
Claims (3)
1. a kind of motor control method of irregular carrier wave slope Stochastic Modulation, it is characterised in that: the motor control of the method
System includes three-phase motor (1), voltage source inverter bridge (2), modulating wave generation module (3), random PWM generation module (4)；Wherein
Three-phase motor (1) is connected with the output of the three-phase of voltage source inverter bridge (2), instructs Setting signal R*With feedback signal ia、ib, θ conduct
The input of modulating wave generation module (3), and export modulating wave Ta、Tb、TcIt is given to random PWM generation module (4) and is used as input, with
Machine PWM generation module (4) exports 6 road PWM and is connected with voltage source inverter bridge (2)；
The random PWM generation module (4) includes: random carrier modulation block (4-1), fiducial value computing module (4-2), PWM
Modulation module (4-3)；Compared with random carrier modulation block (4-1) modulation generates carrier amplitude 2TR and stochastic variable TM and is given to
It is worth computing module (4-2), PWM modulation module (4-3), 3 road modulating wave Ta、Tb、TcAnd 2TR, TM are through fiducial value computing module (4-
2) fiducial value cva1, cva2, cva3, cvb1, cvb2, cvb3 are exported and with 2TR, TM collectively as PWM modulation module (4-3)
Input, PWM modulation module (4-3) export input of the PWM as voltage source inverter bridge (2)；
Irregular carrier wave feature is in the random carrier modulation block (4-1), in a cycle TsIt is interior, with slope k1Since 0
By time β TsAmplitude increases to TR afterwards, then with slope k2Start when amplitude is reduced to end cycle to be 0；The sawtooth carrier wave is special
Sign is, in a cycle TsIt is interior, with fixed slope k3Cycle T is begun to pass through from 0sAmplitude increases to 2TR afterwards, then instantaneous to reduce
It is 0, wherein fixed sawtooth carrier wave slope k3It is represented by fixed sawtooth carrier wave amplitude 2TR and cycle TsRatio, sawtooth carrier wave is solid
Its carrier wave slope k of rule3It remains unchanged；Irregular carrier wave is represented by slope k at random1、k2Random variation, and the relationship of the two
It indicates are as follows:
Variable β determines irregular carrier wave slope k in above formula1、k2Value size, and the value range of β be [0,1], so right
The STOCHASTIC CONTROL of variable β is exactly to irregular carrier wave slope k1、k2STOCHASTIC CONTROL；
In same period, irregular carrier wave slope k1、k2Random variation, it is corresponding cause variable TM in fixed sawtooth carrier wave with
Machine variation, TM and k1Between relational expression are as follows:
Variable TM is by k in formula1It determines, and k1Determined by variable β, so variable TM is determined by β, and its value range be [0,
2TR]；
The fiducial value computing module (4-2) passes through input variable Ta、Tb、Tc, 2TR, TM calculate each fixed sawtooth carrier wave period
TsIn 6 fiducial values size, calculation method are as follows:
R in formulaa(t)、rb(t)、rc(t) indicate that the modulating wave of 3 120 ° of tunnel phase mutual deviations, waveform are saddle wave；
The PWM modulation module (4-3) is used to generate 6 road random PWM pulses, it is characterized in that, digital signal processor generates week
Phase is Ts, amplitude is the fixation sawtooth carrier wave of 2TR, the asymmetric random PWM pulse in 3 tunnels is then generated compared with 6 fiducial values,
Remaining 3 tunnel complementary outputs.
2. the motor control method of irregular carrier wave slope Stochastic Modulation according to claim 1, which is characterized in that it is described with
In machine modulator approach the electric machine phase current sampling period remain unchanged and with carrier cycle TsIt is equal.
3. the motor control method of irregular carrier wave slope Stochastic Modulation according to claim 1, which is characterized in that it is described with
Machine modulator approach is in a carrier cycle, each voltage vector resultant action time T0、T1、T3It remains unchanged, Zero voltage vector U0Make
With time t0、t′0Random variation, effective voltage vector U1、U3Action time t1、t3、t′1、t′3Random variation, voltage pulse position
TrRandom variation.
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| CN110768560A (en) * | 2019-10-30 | 2020-02-07 | 渤海大学 | Half-period three-pulse-wave low-quality-factor series resonance type medium-frequency induction heating inversion control method |
| CN110875691A (en) * | 2019-09-09 | 2020-03-10 | 北京索德电气工业有限公司 | PWM modulation method for elevator frequency converter |
| CN111769747A (en) * | 2020-06-15 | 2020-10-13 | 珠海格力电器股份有限公司 | Control device and method of frequency converter and frequency converter |
| CN112910347A (en) * | 2021-01-21 | 2021-06-04 | 西安理工大学 | Dual-random SVPWM harmonic suppression method based on Meisen rotation algorithm |
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| CN112910347A (en) * | 2021-01-21 | 2021-06-04 | 西安理工大学 | Dual-random SVPWM harmonic suppression method based on Meisen rotation algorithm |
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