CN115800829A - Feedback boost inverter for inhibiting torque ripple of brushless direct current motor and control method - Google Patents
Feedback boost inverter for inhibiting torque ripple of brushless direct current motor and control method Download PDFInfo
- Publication number
- CN115800829A CN115800829A CN202211439779.8A CN202211439779A CN115800829A CN 115800829 A CN115800829 A CN 115800829A CN 202211439779 A CN202211439779 A CN 202211439779A CN 115800829 A CN115800829 A CN 115800829A
- Authority
- CN
- China
- Prior art keywords
- insulated gate
- gate bipolar
- bipolar transistor
- electrolytic capacitor
- phase
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Landscapes
- Control Of Motors That Do Not Use Commutators (AREA)
Abstract
The invention discloses a feedback boost inverter for inhibiting torque pulsation of a brushless direct current motor and a control method, and relates to the technical field of brushless direct current motor control. The feedback boost inverter for inhibiting the torque ripple of the brushless direct current motor comprises a feedback boost inverter topology which is adjustable in size and can be higher than power supply voltage, the feedback boost inverter topology comprises an electrolytic capacitor, seven diodes and seven insulated gate bipolar transistors, and compared with a traditional inverter, only one insulated gate bipolar transistor, one diode and one electrolytic capacitor are additionally needed.
Description
Technical Field
The invention relates to the technical field of brushless direct current motor control, in particular to a feedback boost inverter for inhibiting torque ripple of a brushless direct current motor and a control method.
Background
Brushless direct current motors (BLDCM) have advantages of high power density, simple structure, small volume, high efficiency, and the like, and are widely used in the fields of aerospace, electric vehicles, medical devices, household appliances, and the like. However, the torque ripple problem of the BLDCM is limited for high precision, high stability applications where the torque ripple due to current commutation can reach up to 50% of the average torque, so suppressing the BLDCM commutation torque ripple is a hot spot in studying torque ripple suppression.
The existing BLDCM commutation torque ripple suppression method can be largely summarized into three types: (1) changing a modulation mode: the modulation method is changed to inhibit the pulsation of non-commutation phase current in the commutation period, so as to inhibit the pulsation of commutation torque; (2) direct torque control: the intermediate link is omitted, and the electromagnetic torque of the motor is directly controlled, so that the method has good robustness on the influence of the parameter change of the motor in the operation process; (3) raising the bus voltage during commutation: bus voltage is raised during phase commutation, the falling amplitude of non-commutation phase current is reduced, and then torque ripple is restrained.
The Boost topology applied to the BLDCM is mostly Cuk, SEPIC, buck-Boost and other circuits, a large number of switching devices and additional inductors are needed, and the volume and the cost of the system are inevitably and greatly increased.
Disclosure of Invention
Compared with the traditional inverter, the inverter only needs one insulated gate bipolar transistor, one diode and one electrolytic capacitor additionally, and is simple in structure and convenient to control. Based on the feedback boost inverter, the invention provides a feedback boost inverter control method for inhibiting the torque ripple of the brushless direct current motor, which can realize that the BLDCM has good torque ripple inhibition effect in a wide speed range.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows: suppression ofA feedback boost inverter for brushless DC motor torque ripple includes a feedback boost inverter topology providing an adjustable magnitude and capable of being higher than the supply voltage, the feedback boost inverter topology including an electrolytic capacitor C 0 Zero diode VD 0 Diode VD 6 Zero-number insulated gate bipolar transistor VT 0 First insulated gate bipolar transistor VT forming A-phase bridge arm 1 And a second insulated gate bipolar transistor VT 2 Third insulated gate bipolar transistor VT forming B phase bridge arm 3 And fourth insulated gate bipolar transistor VT 4 And a fifth insulated gate bipolar transistor VT forming a C-phase bridge arm 5 And six insulated gate bipolar transistor VT 6 The first insulated gate bipolar transistor VT 1 Third insulated gate bipolar transistor VT 3 And V insulated gate bipolar transistor VT 5 Respectively with a second insulated gate bipolar transistor VT 2 Fourth insulated gate bipolar transistor VT 4 And six insulated gate bipolar transistor VT 6 Is connected with the collector of the second insulated gate bipolar transistor VT 2 Fourth insulated gate bipolar transistor VT 4 And six insulated gate bipolar transistor VT 6 Respectively with a power supply U dc The cathodes are directly connected and are respectively connected with a second diode VD in an anti-parallel way 2 Diode VD 4 And a sixth diode VD 6 The first insulated gate bipolar transistor VT 1 Third insulated gate bipolar transistor VT 3 And V insulated gate bipolar transistor VT 5 Collector and zero diode VD 0 Is connected to the cathode of the zero diode VD 0 Anode and power supply U dc The positive electrodes are connected, and the electrolytic capacitor C 0 Respectively with the positive electrode of a zero-sign insulated gate bipolar transistor VT 0 Collector electrode, first diode VD 1 Diode VD 3 And diode VD 5 Is connected to the cathode of the electrolytic capacitor C 0 Negative electrode and power supply U dc The positive electrodes are connected, and the zero-number insulated gate bipolar transistor VT 0 Emitter and zero diode VD 0 Of the heartPole connected, the first diode VD 1 Diode VD 3 And diode VD 5 Respectively with a first insulated gate bipolar transistor VT 1 Third insulated gate bipolar transistor VT 3 And V insulated gate bipolar transistor VT 5 Are connected.
The technical scheme of the invention is further improved as follows: the electrolytic capacitor C 0 Capacity value C of * Satisfies the following conditions:
in the formula I N Rated current, T, for brushless DC motors c Is a switching cycle; u shape TH Loop width for hysteresis control; l is the equivalent inductance of the phase winding, V dc Is the supply voltage, J is the moment of inertia, K e Are the opposite potential coefficients.
The technical scheme of the invention is further improved as follows: the control method of the feedback boost inverter for inhibiting the torque ripple of the brushless DC motor comprises the following steps:
s1, obtaining a rotor position theta of the brushless direct current motor through a position sensor, and obtaining an actual mechanical angular velocity omega of the brushless direct current motor through the rotor position theta through a rotating speed calculating unit m ；
Step S2, setting mechanical angular velocity
With actual mechanical angular velocity omega m Making difference and obtaining non-commutation phase current reference value by speed PI controller ASR
；
S3, inputting the rotor position theta into a sector judging unit to obtain sector information S;
step S4, converting the sector information S and the three-phase current i A 、i B 、i C Input to the phase current selection unit to obtain the actual non-commutation phaseCurrent i n_com And turn off phase current i out ；
Step S5, the reference value of the non-commutation phase current
With actual non-phase-change phase current i n_com Making a difference and obtaining a duty ratio D related to the current through a current PI controller ACR 1 Duty ratio D related to back emf 2 Adding to obtain a duty ratio D in a non-commutation period;
step S6, converting the actual mechanical angular velocity omega m Input to the rotation speed high-low state judgment unit to obtain the rotation speed high-low state S ω ，S ω 1 represents the motor operating in the high speed region, S ω The value of 0 represents that the motor runs in a low-speed interval;
step S7, obtaining the electrolytic capacitor voltage U by the voltage sensor C0 And high and low rotation speed state S ω Input to the electrolytic capacitor charge-discharge state judgment unit to obtain the electrolytic capacitor charge-discharge state S C ，S C To 1 represents the need to charge the electrolytic capacitor, S C A value of 0 indicates that the electrolytic capacitor does not need to be charged;
step S8, turning off phase current i out Input to a commutation signal judgment unit to obtain a commutation signal S com When phase current i is turned off out When approaching 0, S com Is 0, indicating that the brushless DC motor is in the non-commutation period, otherwise, S com 1, indicating that the brushless direct current motor is in a phase change period;
step S9, setting the duty ratio D and the rotating speed high-low state S in the non-commutation period ω Phase-change signal S com And the charging and discharging state S of the electrolytic capacitor C Inputting the actual duty ratio D into a duty ratio conversion unit to obtain the actual duty ratio D required by the state lookup table of the insulated gate bipolar transistor * ；
Step S10, comparing the actual duty ratio D * And the charging and discharging state S of the electrolytic capacitor C High and low rotation speed state S ω Sector information S, commutation signal S com Inputting the data into a state lookup table of the insulated gate bipolar transistor to obtain a zero-number insulated gate bipolar transistor VT 0 No. six insulated gate bipolar transistor VT 6 The actual switching signal is used for controlling the feedback boost inverter to drive the brushless direct current motor to operate.
The technical scheme of the invention is further improved as follows: the back emf-related duty cycle D in step S5 2 The calculation formula of (c) is as follows:
the technical scheme of the invention is further improved as follows: the rotation speed high-low state determination unit in the step S6 is:
wherein k represents the current time, U COL Is S ω The lower limit of the electrolytic capacitor voltage is 0.
The technical scheme of the invention is further improved as follows: the unit for judging the charging and discharging state of the electrolytic capacitor in the step S7 is as follows:
when S is ω When the average molecular weight is 0, the average molecular weight,
when S is ω When the number of the carbon atoms is 1,
the technical scheme of the invention is further improved as follows: the actual duty ratio D in the step S9 * The calculation formula of (2) is as follows:
when S is ω ＝0，S com When =1, D * ＝2D；
When S is ω ＝1，S com ＝0，S C When the ratio is not less than 1,
other states, D * ＝D。
The technical scheme of the invention is further improved as follows: the state lookup table of the igbt in step S10 includes zero-numbered igbts VT of 6 sectors in the non-commutation period and 6 commutation sectors in the commutation period in a state where the motor operates in the high-speed region or the low-speed region and whether the electrolytic capacitor needs to be charged 0 No. six insulated gate bipolar transistor VT 6 The switch state of (a).
Due to the adoption of the technical scheme, the invention has the technical progress that:
1. compared with the boost topology applied to BLDCM at present, the feedback boost inverter topology provided by the invention has the advantages of simple structure and convenience in control, the energy of the electrolytic capacitor for boosting the bus voltage in the topology is all from the energy fed back by the motor, the energy utilization rate of the motor is improved without an external power supply, and the control method can play a good torque ripple suppression effect in a wide rotating speed range;
2. the invention has set forth the suppression method of torque ripple of wide speed range of brushless DC motor based on feedback boost inverter, when the motor runs at low speed, because the bus voltage that the commutation needs is smaller than the mains voltage, therefore can inhibit the commutation torque ripple through the way of pulse width modulation; in the high-speed operation, however, it is necessary to supply a bus voltage higher than the power supply voltage in order to achieve rapid commutation while maintaining the non-commutation phase current at the time of commutation stable. Therefore, an electrolytic capacitor can be connected in series to the DC power supply side during commutation to raise the bus voltage and thereby suppress commutation torque ripple. The energy of the electrolytic capacitor for raising the bus voltage is totally fed back from the motor, and an additional power supply is not needed.
Drawings
FIG. 1 is a schematic diagram of a feedback boost inverter circuit according to an embodiment of the present invention;
FIG. 2 is a control block diagram of a regenerative boost inverter control method for suppressing torque ripple of a brushless DC motor in an embodiment of the present invention;
FIG. 3 shows the time S during non-commutation period in an embodiment of the present invention ω ＝0，S C When =0, the circulation path of the AB-phase on-current is schematically illustrated, where the diagrams (a) and (b) are VT respectively 1 A schematic diagram of a current path when the current is switched on and off;
FIG. 4 shows the time S when the phase is not during commutation in the embodiment of the present invention ω ＝0，S C The circulation path of the AB-phase conduction current is schematically shown in the drawing (a) and the drawing (b) are VT respectively when the current is 1 1 A schematic diagram of a current path when the current is switched on and off;
FIG. 5 shows the time S when the phase is not in commutation period in the embodiment of the present invention ω ＝1，S C When =0, the circulation path of the AB-phase on-current is schematically illustrated, where the diagrams (a) and (b) are VT respectively 1 A schematic diagram of a current path when the current is switched on and off;
FIG. 6 shows the time S during non-commutation period in an embodiment of the present invention ω ＝1，S C Where =1, the circulation path of the AB-phase on-current is schematically illustrated, where the diagrams (a) and (b) are VT respectively 4 A schematic diagram of a current path when switching on and switching off;
FIG. 7 shows the S phase during commutation period in an embodiment of the present invention ω ＝0，S C When =0, the circulation path of the current is switched from the CB phase conduction to the AB phase conduction, where the diagrams (a) and (b) are VT respectively 1 A schematic diagram of a current path when the current is switched on and off;
FIG. 8 shows the time S during commutation in an embodiment of the present invention ω ＝0，S C When =1, the circulation path of the current is switched from the CB phase conduction to the AB phase conduction, where the diagrams (a) and (b) are VT respectively 1 A schematic diagram of a current path when the current is switched on and off;
FIG. 9 shows S as the phase change period in an embodiment of the present invention ω And when the current is 1, the circulation path is changed from CB-phase conduction to AB-phase conduction current.
Detailed Description
In order to make the technical solutions of the present invention better understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without making any creative effort based on the embodiments in the present invention, shall fall within the protection scope of the present invention.
It should be noted that the terms "a," "an," "two," etc. in the description and claims of the present invention and in the above-described drawings are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the invention described herein are capable of operation in other sequences than those illustrated or described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.
Referring to fig. 1, a feedback boost inverter for suppressing torque ripple of a brushless dc motor includes a feedback boost inverter topology providing a variable magnitude voltage higher than a power supply voltage, the feedback boost inverter topology including an electrolytic capacitor C 0 Zero diode VD 0 Diode VD 6 Zero insulated gate bipolar transistor (VT) 0 First insulated gate bipolar transistor VT forming A-phase bridge arm 1 And a second insulated gate bipolar transistor VT 2 Third insulated gate bipolar transistor VT forming B phase bridge arm 3 And fourth insulated gate bipolar transistor VT 4 And a fifth insulated gate bipolar transistor VT forming a C-phase bridge arm 5 And six insulated gate bipolar transistor VT 6 The first insulated gate bipolar transistor VT 1 Third insulated gate bipolar transistor VT 3 And V insulated gate bipolar transistor VT 5 Respectively with a second insulated gate bipolar transistor VT 2 Fourth insulated gate bipolar transistor VT 4 And six insulated gate bipolar transistor VT 6 Is connected with the collector of the second insulated gate bipolar transistor VT 2 Fourth insulated gate bipolar transistor VT 4 And six insulated gate bipolar transistor VT 6 Respectively with a power supply U dc The cathodes are directly connected and are respectively connected with a second diode VD in an anti-parallel way 2 Diode VD 4 And number six diode VD 6 The first insulated gate bipolar transistor VT 1 Third insulated gate bipolar transistor VT 3 And V insulated gate bipolar transistor VT 5 Collector and zero diode VD 0 Is connected with the cathode of the zero diode VD 0 Anode and power supply U dc Positive electrodes are connected, and the electrolytic capacitor C 0 Respectively connected with a zero-number insulated gate bipolar transistor VT 0 Collector electrode, first diode VD 1 Diode VD 3 And diode VD 5 Is connected to the cathode of the electrolytic capacitor C 0 Negative electrode and power supply U dc The positive electrodes are connected, and the zero-number insulated gate bipolar transistor VT 0 Emitter and zero diode VD 0 Is connected with the cathode of the first diode VD 1 Diode VD 3 And diode VD 5 Respectively with a first insulated gate bipolar transistor VT 1 Third insulated gate bipolar transistor VT 3 And V insulated gate bipolar transistor VT 5 Are connected.
Wherein, the electrolytic capacitor C 0 Capacity value C of * Satisfies the following conditions:
in the formula I N Rated current, T, for brushless DC motors c Is a switching cycle; u shape TH Loop width for hysteresis control; l is the equivalent inductance of the phase winding, V dc Is the supply voltage, J is the moment of inertia, K e Are of opposite potential coefficients.
Referring to fig. 2, which shows a control block diagram of a feedback boost inverter control method for suppressing torque ripple of a brushless dc motor according to an embodiment of the present invention, the method involves a rotation speed calculation unit, a speed PI controller ASR, a sector judgment unit, a phase current selection unit, a current PI controller ACR, a rotation speed high/low state judgment unit, an electrolytic capacitor charging/discharging state judgment unit, a phase-change signal judgment unit, a duty ratio conversion unit, an igbt state lookup table, a feedback boost inverter, and a BLDCM during torque ripple suppression, and the method includes:
s1, obtaining a rotor position theta of the brushless direct current motor through a position sensor, and obtaining an actual mechanical angular velocity omega of the brushless direct current motor through the rotor position theta through a rotating speed calculating unit m ；
Step S2, setting mechanical angular speed
And actual mechanical angular velocity omega m Making difference and obtaining non-commutation phase current reference value by speed PI controller ASR
；
S3, inputting the rotor position theta into a sector judging unit to obtain sector information S, and judging a commutation signal by detecting the rotor position required by the driving of the brushless direct current motor so as to divide the brushless direct current motor into six sectors;
step S4, converting the sector information S and the three-phase current i A 、i B 、i C Input to a phase current selection unit to obtain an actual non-commutation phase current i n_com And turn off phase current i out ；
Step S5, reference value of non-phase-change phase current
With actual non-phase-change phase current i n_com Making a difference and obtaining a duty ratio D related to the current through a current PI controller ACR 1 Duty ratio D related to back emf 2 AddingObtaining the duty ratio D during the non-commutation period, wherein the back emf is related to the duty ratio D 2 Calculated from the formula:
step S6, converting the actual mechanical angular velocity omega m Input to the rotation speed high-low state judgment unit to obtain the rotation speed high-low state S ω ，S ω 1 represents the motor operating in the high speed region, S ω The value of 0 represents that the motor runs in a low-speed interval; the rotating speed high-low state judging unit is as follows:
step S7, obtaining the electrolytic capacitor voltage U by the voltage sensor C0 And high and low rotation speed state S ω Input to the electrolytic capacitor charging and discharging state judgment unit to obtain the charging and discharging state S of the electrolytic capacitor C ，S C To 1 represents the need to charge the electrolytic capacitor, S C A value of 0 indicates that the electrolytic capacitor does not need to be charged;
the electrolytic capacitor charging and discharging state judging unit comprises:
when S is ω When the average molecular weight is 0, the average molecular weight,
where k denotes the current time, U C0L Is S ω Lower limit of electrolytic capacitor voltage when it is 0;
when S is ω When the number of the carbon atoms is 1,
step S8, turning off the phase current i out Input to a commutation signal judgment unit to obtain a commutation signal S com Commutation signal S at commutation com Is 1, the commutation is over S com Is 0. Here, in order to determine whether or not the phase change is completed, the off-phase current i is detected out And when the phase is close to 0, the phase commutation is finished. When phase current i is off out Near 0, S com Is 0, indicating that the brushless DC motor is in the non-commutation period, otherwise, S com 1, indicating that the brushless direct current motor is in a phase change period;
step S9, setting the duty ratio D and the rotating speed high-low state S in the non-commutation period ω Phase-change signal S com And the charging and discharging state S of the electrolytic capacitor C Inputting the actual duty ratio D into a duty ratio conversion unit to obtain the actual duty ratio D required by the state lookup table of the insulated gate bipolar transistor * Which satisfies:
when S is ω ＝0，S com When the ratio is not less than 1,
D * ＝2D；
when S is ω ＝1，S com ＝0，S C When the ratio is not less than 1,
in the other state of the system, the state of the system,
D * ＝D；
step S10, comparing the actual duty ratio D * And the charging and discharging state S of the electrolytic capacitor C High and low rotation speed state S ω Sector information S, commutation signal S com Inputting the data into a state lookup table of the insulated gate bipolar transistor to obtain a zero-number insulated gate bipolar transistor VT 0 No. six insulated gate bipolar transistor VT 6 The actual switching signal is used for controlling the feedback boost inverter to drive the brushless direct current motor to operate.
The state lookup table of the insulated gate bipolar transistor comprises zero-numbered insulated gate bipolar transistors VT of 6 sectors in a non-commutation period and 6 commutation sectors in a commutation period under the state that the motor runs in a high-speed region or a low-speed region and whether an electrolytic capacitor needs to be charged 0 About six insulated gate bipolar transistor VT 6 The switch state of (a).
The status lookup table of the insulated gate bipolar transistor is divided into a status lookup table of the insulated gate bipolar transistor during non-commutation and commutation, and is as follows:
TABLE 1 state lookup table for IGBT during non-commutation period
TABLE 2 state lookup table for IGBT during commutation
Wherein, I represents a sector I, VI → I represents a sector VI to commutate to the sector I, and other similar units have similar signs; seven bits in each sector sequentially represent the switching states from the zero-number insulated gate bipolar transistor to the six-number insulated gate bipolar transistor, 1 represents conduction, 0 represents disconnection, and D represents * Is expressed in actual duty cycle D * Chopping is carried out; high and low rotating speed state S ω The value of 0 represents that the current time is low-speed operation, and the value of 1 represents high-speed operation; charging and discharging state S of electrolytic capacitor C A value of 0 indicates that charging is not required at the present time, a value of 1 indicates that charging is required, and/indicates that selection of the state lookup table of the igbt is not affected.
Conducting states of the insulated gate bipolar transistors in different circuit modes in the state query table of the insulated gate bipolar transistors are analyzed, the state query table of the insulated gate bipolar transistors in a non-commutation period is explained by taking the condition that a rotor is positioned in a first sector, namely AB conducting, as an example, and other sectors can be analyzed in an analog mode.
When the rotating speed is high or low state S ω When the voltage is 0, the motor is indicated to be operated at low speed currently, and a PWM-ON modulation mode with the phase change torque and the minimum pulse is adopted, so that AB conduction is that the tube chopping of the A phase tube is carried out under the B phaseThe tube is constantly switched on, at the moment, if the zero insulated gate bipolar transistor is switched on, the electrolytic capacitor is discharged, and if the zero insulated gate bipolar transistor is switched off, the electrolytic capacitor is not discharged nor charged, so that when the electrolytic capacitor is in a charging and discharging state S C 1, i.e. when the electrolytic capacitor needs to be charged, the conducting state of the IGBT is 0N * 0 charge 01 charge 00; when the electrolytic capacitor is in a charging/discharging state S C When the current is 0, namely the electrolytic capacitor does not need to be charged, the conducting state of the insulated gate bipolar transistor is 1N * 0 is 01 and 00; when the rotating speed is high or low state S ω When the current motor speed is 1, the motor runs at a high speed, and the motor needs to be charged, namely the charging and discharging state S of the electrolytic capacitor at the moment C When the current value is 1, in order to enable all the feedback energy of the motor to be used for charging the electrolytic capacitor, an H _ ON-L _ PWM mode modulation mode is adopted, so that the conduction state of the insulated gate bipolar transistor at the time is 0 to 10 to 0D * I 00; without charging the motor, i.e. the charging and discharging states S of the electrolytic capacitor C When the number of cells is 0, in order to ensure that the electrolytic capacitor discharge is completely carried out in the phase change period, an H _ PWM-L _ ON modulation mode is adopted, so that the conducting state of the insulated gate bipolar transistor at the moment is 0Y * 0|01|00。
For the state lookup table of the insulated gate bipolar transistor during the phase commutation, the phase commutation from the sector VI to the sector I is taken as an example for explanation, and other sectors can be analyzed in an analog manner.
When the rotating speed is high or low state S ω When the current speed is 0, the motor runs at a low speed, the bus voltage does not need to be raised, the duty ratio in the non-commutation period is only increased to 2 times of the original duty ratio, and the switching state of the motor is consistent with that of the sector I; when the rotating speed is high or low state S ω When the number of the cells is 1, the current motor runs at a high speed, the bus voltage needs to be raised, and the zero insulated gate bipolar transistor needs to be turned on, so that the conducting state of the insulated gate bipolar transistor is 1 cell, 10 cells 01 cells 00 cells.
Further, duty cycle D * The calculation method of (2) is as follows:
during non-commutation period, when S ω ＝0，S C Fig. 3 illustrates a schematic diagram of the circulation path of the AB-phase on-current when =0, where (a) and (b) are VT 1 Current at turn-on or turn-offFlow path schematic, VT 0 Constant velocity, VT 1 At the actual duty cycle D * Chopping, VT 4 Constant-current, the voltage of the A-phase stator winding endpoint and the B-phase stator winding endpoint relative to the negative pole of the power supply is D * (V dc +U C0 ) 0 at S ω U at =0 C0 ＜＜V dc Thus D * (V dc +U C0 ) Can be approximated as D * V dc At this time, phase current i A ＝-i B ＝I N Opposite electromotive force e A ＝-e B ＝E＝K e ω m The voltage equation for the winding is:
as can be seen from the equation (1), the duty ratio D at this time is set to maintain the non-commutation phase current stable * Satisfies the following conditions:
during non-commutation period, when S is ω ＝0，S C Fig. 4 shows a schematic diagram of a circulation path of the AB-phase on-current when =1, where (a) and (b) are VT respectively 1 Schematic diagram of current flow path during turn-on and turn-off, VT 0 Off, VT 1 At the actual duty cycle D * Chopping, VT 4 Constant-current, the voltage of the A-phase stator winding endpoint and the B-phase stator winding endpoint relative to the negative pole of the power supply is D * V dc 0, phase current i A ＝-i B ＝I N Opposite electromotive force e A ＝-e B = E, the voltage equation of the winding is:
as can be seen from equation (3), the actual duty ratio D at this time is set to maintain the non-commutation phase current stable * Satisfies the following conditions:
during non-commutation period, when S is ω ＝1，S C Fig. 5 illustrates a schematic flow path of the AB-phase on-current when =0, where (a) and (b) are VT 1 Schematic diagram of current flow path during turn-on and turn-off, VT 0 Off, VT 1 At the actual duty cycle D * Chopping, VT 4 Constant-current, the voltage of the A-phase stator winding endpoint and the B-phase stator winding endpoint relative to the negative pole of the power supply is D * V dc 0, phase current i A ＝-i B ＝I N Opposite electromotive force e A ＝-e B = E, the voltage equation of the winding is:
as can be seen from the equation (5), the duty ratio D at this time is set to maintain the non-commutation phase current stable * Satisfies the following conditions:
during non-commutation period, when S is ω ＝1，S C Fig. 6 shows a schematic diagram of a circulation path of the AB-phase on-current when =1, where (a) and (b) are VT 4 Schematic diagram of current flow path at turn-on and turn-off, VT 0 Off, VT 1 Constant voltage constant, VT 4 At the actual duty cycle D * Chopping, the voltage of the A-phase stator winding end point and the B-phase stator winding end point relative to the negative pole of the power supply is V dc 、(1-D * )(V dc +U C0 ) Phase current i A ＝-i B ＝I N Opposite electromotive force e A ＝-e B = E, the voltage equation of the winding is:
as can be seen from the equation (7), the duty ratio D at this time is set to maintain the non-commutation phase current stable * Satisfies the following conditions:
during commutation, when S ω ＝0，S C Fig. 7 shows a schematic diagram of a flow path for switching from CB-phase conduction to AB-phase conduction current when =0, where (a) and (b) are VT 1 Schematic diagram of current flow path at turn-on and turn-off, VT 0 Constant voltage constant, VT 1 At the actual duty cycle D * Chopping, VT 4 Constant-current, the voltage of the A, B and C phase stator winding end point relative to the negative pole of the power supply is D * (V dc +U C0 ) 0, at S ω U at =0 C0 ＜＜V dc Thus D * (V dc +U C0 ) Can be approximated by D * V dc Opposite electromotive force e A ＝-e B ＝e C = E, the voltage equation for the winding is:
as can be seen from equation (9), the actual duty ratio D at this time is set to maintain the non-commutation phase current stable * Satisfies the following conditions:
during commutation, when S ω ＝0，S C Fig. 8 shows a schematic diagram of a flow path for switching from CB-phase conduction to AB-phase conduction current when =1, where (a) and (b) are VT 1 Schematic diagram of current flow path at turn-on and turn-off, VT 0 Off, VT 1 At the actual duty cycle D * Chopping, VT 4 Constant-current, the voltage of the A, B and C phase stator winding end points relative to the negative pole of the power supply is D * V dc 0, counter electromotive force e A ＝-e B ＝e C = E, the voltage equation of the winding is:
as can be seen from equation (11), the actual duty ratio D at this time is such that the non-commutation phase current is kept stable * Satisfies the following conditions:
during commutation, when S ω Fig. 9 shows a schematic diagram of a flow path for switching from CB-phase conduction to AB-phase conduction current when =1, VT 0 Constant voltage constant, VT 1 Constant voltage constant, VT 4 Constant-current, the voltage of the A, B and C phase stator winding end points relative to the negative pole of the power supply is V dc +U C0 0, counter electromotive force e A ＝-e B ＝e C = E, the voltage equation for the winding is:
further, the capacitance value C of the electrolytic capacitor * The following is selected as follows:
when S is ω When =0, electrolytic capacitor C in single switching period under rated load 0 Electrolytic capacitor C caused by charging and discharging 0 The voltage rise and drop should be far less than the loop width U of hysteresis control TH Based on the charge and discharge equivalent circuit in low-speed operation, electrolytic capacitor C 0 Maximum value of boost Δ U C0L_up Maximum value of reduced pressure Δ U C0L_down As shown in formula (14):
during commutation, when S ω Electrolytic capacitor C under rated load when =1 0 Maximum voltage drop DeltaU caused by discharge C0H_down Loop width U should be less than hysteresis control TH As shown in formula (15):
when S is ω =1 and when the motor rotation speed changes, the electrolytic capacitor C 0 The charging and discharging rate is larger than that of the electrolytic capacitor C 0 The rate at which the voltage expectation value changes, as shown in equation (16):
from the expressions (14) to (16), the capacitance value C of the electrolytic capacitor can be obtained * The selection method of (2) is shown in formula (17):
in the formula I N Rated current, T, for brushless DC motors c Is a switching cycle; u shape TH Loop width for hysteresis control; l is the equivalent inductance of the phase winding, V dc Is the supply voltage, J is the moment of inertia, K e Are the opposite potential coefficients.
The feedback boost inverter topology circuit adopted in the embodiment of the invention can realize the purpose of feeding the electrolytic capacitor C by utilizing the self feedback of the motor 0 Charging, need not plus the energy utilization of power has promoted the motor, can both play good torque ripple suppression effect in wide rotational speed range.
Claims (8)
1. The feedback boost inverter for inhibiting the torque ripple of the brushless DC motor is characterized in that: comprises providing a feedback boost inverter topology having an adjustable magnitude and capable of being higher than a power supply voltage, the feedback boost inverter topology including an electrolytic capacitor C 0 Zero diode VD 0 Number sixDiode VD 6 Zero insulated gate bipolar transistor (VT) 0 First insulated gate bipolar transistor VT forming A-phase bridge arm 1 And a second insulated gate bipolar transistor VT 2 Third insulated gate bipolar transistor VT forming B phase bridge arm 3 And fourth insulated gate bipolar transistor VT 4 Five insulated gate bipolar transistors VT forming C-phase bridge arm 5 And six insulated gate bipolar transistor VT 6 The first insulated gate bipolar transistor VT 1 Third insulated gate bipolar transistor VT 3 And V insulated gate bipolar transistor VT 5 Respectively with a second insulated gate bipolar transistor VT 2 Fourth insulated gate bipolar transistor VT 4 And six insulated gate bipolar transistor VT 6 Is connected with the collector of the second insulated gate bipolar transistor VT 2 Fourth insulated gate bipolar transistor VT 4 And six insulated gate bipolar transistor VT 6 Respectively with a power supply U dc The cathodes are directly connected and are respectively connected with a second diode VD in an anti-parallel way 2 Diode VD 4 And a sixth diode VD 6 The first insulated gate bipolar transistor VT 1 Third insulated gate bipolar transistor VT 3 And V insulated gate bipolar transistor VT 5 Collector and zero diode VD 0 Is connected with the cathode of the zero diode VD 0 Anode and power supply U dc The positive electrodes are connected, and the electrolytic capacitor C 0 Respectively with the positive electrode of a zero-sign insulated gate bipolar transistor VT 0 Collector electrode, first diode VD 1 Diode VD 3 And diode VD 5 Is connected to the cathode of the electrolytic capacitor C 0 Negative electrode and power supply U dc The positive electrodes are connected, and the zero-number insulated gate bipolar transistor VT 0 Emitter and zero diode VD 0 Is connected with the cathode of the first diode VD 1 Diode VD 3 And diode VD 5 Respectively connected with a first insulated gate bipolar transistor VT 1 Third insulated gate bipolar transistor VT 3 And insulating grid of No. fivePolar transistor VT 5 Are connected.
2. The buck boost inverter for suppressing torque ripple of a brushless dc motor as claimed in claim 1, wherein: the electrolytic capacitor C 0 Capacity value C of * Satisfies the following conditions:
in the formula I N Rated current, T, for brushless DC motors c Is a switching cycle; u shape TH Loop width for hysteresis control; l is the equivalent inductance of the phase winding, V dc Is the supply voltage, J is the moment of inertia, K e Are of opposite potential coefficients.
3. A control method of a feedback boost inverter for suppressing torque ripple of a brushless DC motor is characterized in that: the method comprises the following steps:
s1, obtaining a rotor position theta of the brushless direct current motor through a position sensor, and obtaining an actual mechanical angular velocity omega of the brushless direct current motor through the rotor position theta through a rotating speed calculating unit m ；
Step S2, setting mechanical angular velocity
With actual mechanical angular velocity omega m Making difference and obtaining non-commutation phase current reference value by speed PI controller ASR
S3, inputting the rotor position theta into a sector judging unit to obtain sector information S;
step S4, converting the sector information S and the three-phase current i A 、i B 、i C The phase current selection unit obtains the actual non-commutation phase current i n_com And turn off phase current i out ；
Step S5, reference value of non-phase-change phase current
With actual non-phase-change phase current i n_com Making a difference and obtaining a duty ratio D related to the current through a current PI controller ACR 1 Duty ratio D related to back emf 2 Adding to obtain a duty ratio D in a non-commutation period;
step S6, converting the actual mechanical angular velocity omega m Input to the rotation speed high-low state judgment unit to obtain the rotation speed high-low state S ω ，S ω 1 represents the motor operating in the high speed region, S ω The value of 0 represents that the motor runs in a low-speed interval;
step S7, obtaining the electrolytic capacitor voltage U by the voltage sensor C0 And high and low rotation speed state S ω Input to the electrolytic capacitor charge-discharge state judgment unit to obtain the electrolytic capacitor charge-discharge state S C ，S C To 1 represents the need to charge the electrolytic capacitor, S C A value of 0 indicates that the electrolytic capacitor does not need to be charged;
step S8, turning off phase current i out Input to a commutation signal judgment unit to obtain a commutation signal S com When phase current i is turned off out Near 0, S com A value of 0 indicates that the brushless DC motor is in the non-commutation period, whereas S com 1, indicating that the brushless direct current motor is in a phase change period;
step S9, setting the duty ratio D and the rotating speed high-low state S in the non-commutation period ω Phase-change signal S com And the charging and discharging state S of the electrolytic capacitor C Inputting the actual duty ratio D into a duty ratio conversion unit to obtain the actual duty ratio D required by the state lookup table of the insulated gate bipolar transistor * ；
Step S10, comparing the actual duty ratio D * And the charging and discharging state S of the electrolytic capacitor C High and low rotation speed state S ω Sector information S, commutation signal S com Inputting the state of the IGBT into a lookup table to obtain a zero-number IGBT VT 0 No. six insulated gate bipolar transistor VT 6 Thereby the actual switching signal ofAnd controlling the feedback boosting inverter to drive the brushless direct current motor to operate.
4. The method of claim 3, wherein the step-back inverter comprises: the back emf-related duty cycle D in step S5 2 The calculation formula of (c) is as follows:
5. the method of claim 3, wherein the step-up inverter comprises: the rotation speed high-low state determination unit in the step S6 is:
where k denotes the current time, U C0L Is S ω The lower limit of the electrolytic capacitor voltage is 0.
6. The method of claim 3, wherein the step-up inverter comprises: the electrolytic capacitor charge-discharge state determination unit in the step S7 is:
when S is ω When the average molecular weight is 0, the average molecular weight,
when S is ω When the number of the carbon atoms is 1,
7. the method of claim 3, wherein the step-up inverter comprises: the actual duty ratio D in the step S9 * The calculation formula of (2) is as follows:
when S is ω ＝0，S com When =1, D * ＝2D；
When S is ω ＝1，S com ＝0，S C When the ratio is not less than 1,
other states, D * ＝D。
8. The method of claim 3, wherein the step-up inverter comprises: the state lookup table of the igbt in step S10 includes zero-numbered igbts VT of 6 sectors in the non-commutation period and 6 commutation sectors in the commutation period in a state where the motor operates in the high-speed region or the low-speed region and whether the electrolytic capacitor needs to be charged 0 No. six insulated gate bipolar transistor VT 6 The switch state of (1).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211439779.8A CN115800829A (en) | 2022-11-17 | 2022-11-17 | Feedback boost inverter for inhibiting torque ripple of brushless direct current motor and control method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211439779.8A CN115800829A (en) | 2022-11-17 | 2022-11-17 | Feedback boost inverter for inhibiting torque ripple of brushless direct current motor and control method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115800829A true CN115800829A (en) | 2023-03-14 |
Family
ID=85438451
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211439779.8A Pending CN115800829A (en) | 2022-11-17 | 2022-11-17 | Feedback boost inverter for inhibiting torque ripple of brushless direct current motor and control method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115800829A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117155180A (en) * | 2023-09-07 | 2023-12-01 | 北京易动空间科技有限公司 | Torque pulsation suppression method for brushless direct current motor |
-
2022
- 2022-11-17 CN CN202211439779.8A patent/CN115800829A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117155180A (en) * | 2023-09-07 | 2023-12-01 | 北京易动空间科技有限公司 | Torque pulsation suppression method for brushless direct current motor |
| CN117155180B (en) * | 2023-09-07 | 2024-07-02 | 北京易动空间科技有限公司 | Torque pulsation suppression method for brushless direct current motor |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| AU2019410616B2 (en) | Charging method for power battery, motor control circuit and vehicle | |
| US20210351684A1 (en) | Power conversion apparatus | |
| CN109713949B (en) | Method and system for suppressing torque ripple of brushless direct current motor | |
| CN109873578A (en) | The control method of electric tool and electric tool | |
| CN109039205B (en) | SiC device current source type double three-phase permanent magnet synchronous motor driving system and method | |
| CN110176890B (en) | Brushless direct current motor braking torque control method based on non-inductive hybrid energy storage system | |
| CN113364388A (en) | Drive reconstruction type circuit based on SRM and vehicle-mounted integrated charging and feeding system | |
| CN115800829A (en) | Feedback boost inverter for inhibiting torque ripple of brushless direct current motor and control method | |
| CN111355414A (en) | Vehicle, motor drive device, control method, and readable storage medium | |
| CN115648966A (en) | Motor controller, control unit, electric drive system and electric vehicle | |
| Li et al. | A novel voltage-boosting modulation strategy to reduce DC-link capacitance for brushless DC motor drives | |
| CN108206651B (en) | Nine-switch inverter double-motor driving system and control method thereof | |
| CN110504874B (en) | Brushless direct current motor boosting rotating speed closed-loop control method | |
| CN112290854A (en) | Motor driving system and motor driving control method | |
| CN114865983B (en) | Three-phase alternating current speed regulation system for multiplexing excitation winding | |
| CN112311268B (en) | Multilevel inverter topology and brushless direct current motor direct torque control method | |
| CN202997983U (en) | Integrated dual-motor control system for magnetic-suspension energy-storing flywheel | |
| Şehirli et al. | BLDC speed control by bidirectional battery charger with SEPIC MPPT | |
| CN214707586U (en) | Motor driving system and motor system | |
| CN112311267B (en) | Feedback voltage regulation four-level inverter topology and BLDCM torque ripple suppression method driven by same | |
| Chari et al. | Novel and robust hysteresis current control strategies for a BLDC motor: A simulation study and inverter design | |
| CN108092570A (en) | A kind of non position sensor switch magnetic resistance motor drive system | |
| Kalla et al. | A High-Gain Single-Switch DC-DC converter based speed control of PMBLDCM drive for EV applications | |
| Jia et al. | Wide speed range brushless DC motor torque ripple suppression | |
| Bian et al. | Research on regenerative braking torque ripple suppression of brushless DC motor |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |