KR20210069286A - Apparatus for driving multi-phase motor and method for controlling inverter of the same - Google Patents

Abstract

In accordance with an embodiment of the present invention, provided is a polyphase motor driving device, which comprises: a switching control unit for controlling a turn-on/turn-off operation of each switch included in an inverter for supplying driving power to a polyphase motor; and a fault detection unit for detecting whether the switch corresponding to each phase current is faulty based on a phase current of each phase of the motor. The switching control unit supplies a turn-on signal to each switch of the inverter during a first turn-on section of each switching period in accordance with a normal driving mode, and is converted into a fault tolerance mode when the fault detection unit detects at least one faulty switch. In addition, the switching control unit supplies the turn-on signal to each switch of the inverter during a second turn-on period shorter than the first turn-on period of each switching period in accordance with the fault tolerance mode. The polyphase motor driving device can detect whether each switch included in the inverter is faulty, and can maintain driving of the motor in the fault tolerance mode when detecting the faulty switch. Accordingly, the reliability of driving the motor can be improved.

Description

Polyphase motor driving device and its control method {APPARATUS FOR DRIVING MULTI-PHASE MOTOR AND METHOD FOR CONTROLLING INVERTER OF THE SAME}

The present invention relates to a polyphase motor driving device for driving a polyphase motor and a method for controlling an inverter provided therein.

A polyphase motor includes a rotor that rotates and a plurality of stators around which coils are wound. The electric motor driving device for driving such an electric motor varies the counter electromotive force of at least some of the plurality of stators. At this time, by the attractive or repulsive force between each stator and the rotor, the position of the rotor is changed with respect to the plurality of stators, and the rotor rotates.

The motor driving apparatus may include a polyphase inverter corresponding to a plurality of stators included in the polyphase motor, and a switching controller for controlling turn-on-turn-off operations of each switch included in the polyphase inverter.

A polyphase motor may be, but is not limited to, three phases.

As an example, Prior Document 1 (Korean Patent No. 10-1296161; Announcement on Aug. 19, 2013; Applied by National Chiao Tong University) describes the operation of the motor due to motor control using a multi-phase voltage-type inverter exceeding three phases. Advantages of improving efficiency and magnetic power and reducing stator dynamic losses, noise and pulsating torque are disclosed.

On the other hand, Prior Document 2 (Korean Patent Application Laid-Open No. 10-2015-0088208; published on July 31, 2015; applied to Nidec SR Drives Limited) monitors current sharing between switches of multiple switch pairs and removes the failed module when a failure occurs and interchangeable devices and methods. That is, Prior Document 2 does not disclose any fault-tolerant driving at all. Therefore, according to Prior Document 2, as the driving of the motor is stopped when a failure occurs, there is a problem in that there is a limit in improving the reliability of driving the motor.

In this regard, Prior Document 3 (Korean Patent Application Laid-Open No. 10-2019-0078048; published on July 4, 2019; filed by Korea Electric Research Institute) is an open switch failure diagnosis and tolerance control as a reliability improvement factor regarding a three-phase three-level converter topology. , the neutral point voltage ripple reduction and leakage current reduction are initiated. In addition, Prior Document 3 provides a fault-tolerant switching control method of a 3-phase 3-level ANPC converter that does not require complicated phase control or a process of calculating the phase change and command voltage of each phase due to a failure.

That is, in Prior Document 3, a three-phase three-level ANCP (Active Neutral-Point Clamped) converter that converts the voltage command of the other two phases into a specific fault-tolerant command voltage when any one of the phases in the 3-phase converter has an open fault. Disclosed is a switching control method.

The fault-tolerant switching control method according to this prior document 3 has a problem in that it is difficult to properly apply it to a multi-phase motor driving device having more than three phases. In addition, since the fault-tolerant switching control method according to Prior Document 3 converts the voltage command of two phases other than a fault, it is difficult to prevent an imbalance between the phase in which an open fault has occurred and the remaining two phases, and There is a problem in that it is difficult to prevent an increase in torque ripple and further burnout of the switch.

(Prior Document 1) Korean Patent Registration No. 10-1296161 (Prior Document 2) Korean Patent Laid-Open No. 10-2015-0088208 (Prior Document 3) Korean Patent Laid-Open No. 10-2019-0078048

An object of the present invention is to detect whether a switch is faulty corresponding to the phase current supplied to each phase of a polyphase motor, and to provide fault tolerance control when a fault of at least one switch is detected, thereby improving the reliability of motor driving. An object of the present invention is to provide a multiphase motor driving device and an inverter control method thereof.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a polyphase motor driving apparatus capable of preventing an imbalance between phases due to a switch detected as a failure during fault tolerance control and a method for controlling an inverter thereof.

It is an object of the present invention to provide a motor driving apparatus capable of preventing an increase in torque ripple and additional burnout of a switch due to an imbalance between phases, and a method for controlling an inverter thereof.

The objects of the present invention are not limited to the above-mentioned objects, and other objects and advantages of the present invention not mentioned may be understood by the following description, and will be more clearly understood by the examples of the present invention. Moreover, it will be readily apparent that the objects and advantages of the present invention may be realized by the means and combinations thereof indicated in the claims.

An example of the present invention is a switching controller that controls the turn-on-turn-off operation of each switch included in an inverter that supplies driving power to a polyphase motor, and whether a switch corresponding to each phase current is faulty based on the phase current of each phase of the motor It provides a polyphase motor driving device including a fault detection unit for detecting the. Here, the switching control unit supplies a turn-on signal to each switch of the inverter during the first turn-on section of each switching cycle according to the normal driving mode, while the fault detection unit detects at least one faulty switch, it switches to the fault tolerance mode. In addition, the switching control unit supplies a turn-on signal to each switch of the inverter during a second turn-on period shorter than the first turn-on period of each switching period according to the fault tolerance mode.

Accordingly, it is possible to detect whether each switch included in the inverter is faulty, and when the faulty switch is detected, it is possible to maintain the motor driving in the fault tolerance mode. Accordingly, the reliability of driving the electric motor can be improved.

In addition, the switching controller drives the inverter in the (n-1)-phase energization mode according to the normal driving mode, and drives the inverter in the (n-3)-phase energization mode according to the fault tolerance mode.

The switching control unit derives an allowable replacement section of each switch based on the difference between the first turn-on section and the second turn-on section of each switch, and each unit section included in the second turn-on section of each faulty switch among the replacement allowable sections of the switches and select a replacement allowable section of any one replacement switch corresponding to the phase current by each faulty switch. And, according to the fault tolerance mode, the turn-on signal is supplied to the selected replacement switch instead of the faulty switch.

That is, since the second turn-on period is shorter than the first turn-on period, a replacement allowable period corresponding to each unit period can be derived. Due to this replacement allowable section, a replacement switch in place of the faulty switch can be selected. Therefore, in the fault tolerant mode, due to the turn-on operation of the replacement switch instead of the faulty switch, it is possible to prevent imbalance between phases due to the faulty switch.

In this way, since the imbalance between the phases is prevented, an increase in torque ripple due to the imbalance between the phases can be prevented, and further burnout of the switch when the torque ripple is intensified can also be prevented.

Another example of the present invention relates to a method for a polyphase motor driving device to control an inverter, driving the inverter in an (n-1)-phase energization method according to a general driving mode, and the phase current supplied to each phase of the motor Detecting whether a switch corresponding to each phase current is faulty based on each phase current, if at least one of the switches corresponding to any one phase of the motor is detected as a fault, turning off the at least one faulty switch detected as a fault, There is provided a method for controlling an inverter comprising the steps of switching to a fault tolerance mode, and driving the inverter in an (n-3)-phase energized mode according to the fault tolerance mode. Here, in the step of driving the inverter according to the normal driving mode, each switch of the inverter is turned on during the first turn-on period corresponding to the (n-1)-phase energization method during each switching cycle, and drives the inverter according to the fault tolerance mode In this step, each switch of the inverter is turned on during the second turn-on period corresponding to the (n-3)-phase energization method during each switching period and shorter than the first turn-on period.

The polyphase motor driving device according to an embodiment of the present invention detects whether each switch included in the inverter is faulty, and when at least one of the switches corresponding to any one phase is detected as a fault, it enters the fault tolerance mode. switch Accordingly, even if any one of the switches fails, it is possible to maintain the driving of the motor, so that the reliability of driving the motor can be improved.

And, according to the fault tolerance mode, each switch is turned on during the second turn-on period shorter than the first turn-on period according to the normal driving mode during each switch period. Accordingly, the polyphase motor driving device can be driven in the first turn-on section according to the normal driving mode and is driven in the second turn-on section according to the fault tolerance mode, so the difference between the first and second turn-on sections is to replace the faulty switch. It can be selected as an alternative allowable interval for Accordingly, by turning on the replacement switch providing the replacement allowable section instead of the faulty switch, imbalance between phases due to the faulty switch can be prevented.

Thereby, an increase in torque ripple due to phase-to-phase imbalance can be prevented.

In addition, since the number of energized phases in the fault tolerance mode is smaller than in the normal driving mode, torque ripple can be reduced.

Accordingly, additional burnout of the switch due to the intensification of torque ripple can also be prevented.

Therefore, according to an embodiment of the present invention, the reliability of driving the electric motor can be further improved.

In addition to the above-described effects, the specific effects of the present invention will be described together while describing specific details for carrying out the invention below.

1 is a view showing a polyphase motor driving apparatus according to an embodiment of the present invention.
2 is a view showing an example of an equivalent circuit of the inverter and the polyphase motor of FIG. 1 .
3 is a view showing an inverter control method of a polyphase motor driving apparatus according to an embodiment of the present invention.
FIG. 4 is a diagram illustrating an example of phase current and counter electromotive force of each phase when the inverter of FIG. 2 is driven in a normal driving mode.
FIG. 5 is a diagram illustrating an example of an equivalent circuit of an inverter corresponding to the second unit section of FIG. 4 when the upper end switch of the first switch unit corresponding to the phase a of the inverters of FIG. 2 is faulty.
FIG. 6 is a diagram illustrating an example of phase current and counter electromotive force of each phase when each switch of the inverter of FIG. 2 is turned on during a second turn-on period smaller than the first turn-on period according to the normal driving mode.
FIG. 7 is a diagram showing an example of an allowable replacement period of a phase current by each switch in the inverter of FIG. 2 .
8 is a view showing an example of the phase current and counter electromotive force of each phase according to the fault tolerance mode when the upper switch of the first switch unit corresponding to the phase a of the inverter of FIG. 2 is faulty.
9 is a diagram illustrating an example of an equivalent circuit corresponding to the second unit section of FIG. 8 in the inverter of FIG. 2 .
10 is a view showing an example of the phase current and counter electromotive force of each phase according to the fault tolerance mode when the upper switch of the first switch unit corresponding to the phase a of the inverter of FIG. 2 is faulty.
11 is a view showing an example of the phase current and counter electromotive force of each phase according to the fault tolerance mode when both the upper and lower switches of the second switch unit corresponding to the b phase among the inverters of FIG. 2 fail.
12 is a view showing another example of an equivalent circuit of the inverter and the polyphase motor of FIG. 1 .
13A and 13B are diagrams illustrating an example of the phase current and counter electromotive force of each phase when the inverter of FIG. 12 is driven in the normal driving mode.
14A and 14B are diagrams illustrating an example of the phase current and counter electromotive force of each phase when each switch of the inverter of FIG. 12 is turned on during a second turn-on period smaller than the first turn-on period according to the normal driving mode.
15A and 15B are diagrams illustrating an example of an allowable replacement section of a phase current by each switch in the inverter of FIG. 12 .
FIG. 16 is a diagram illustrating an example of an equivalent circuit of an inverter corresponding to the second unit section of FIG. 13 when the upper switch of the first switch unit corresponding to the phase a of the inverters of FIG. 12 is faulty.
17A and 17B are diagrams illustrating an example of the phase current and counter electromotive force of each phase according to the fault tolerance mode when the upper switch of the first switch unit corresponding to the phase a of the inverter of FIG. 12 is faulty.
18 is a diagram illustrating an example of an equivalent circuit of an inverter corresponding to the second unit section of FIG. 16 .
19A and 19B are diagrams illustrating an example of the phase current and counter electromotive force of each phase according to the fault tolerant mode when both the upper and lower switches of the first switch unit corresponding to phase a of the inverter of FIG. 12 fail.

The above-described objects, features and advantages will be described below in detail with reference to the accompanying drawings, and accordingly, those of ordinary skill in the art to which the present invention pertains will be able to easily implement the technical idea of the present invention. In describing the present invention, if it is determined that a detailed description of a known technology related to the present invention may unnecessarily obscure the gist of the present invention, the detailed description will be omitted. Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to indicate the same or similar components.

Hereinafter, a polyphase motor driving apparatus and an inverter control method thereof according to an embodiment of the present invention will be described with reference to the accompanying drawings.

First, a polyphase motor driving apparatus according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2 .

1 is a view showing a polyphase motor driving apparatus according to an embodiment of the present invention. FIG. 2 is a diagram illustrating an example of an equivalent circuit corresponding to the inverter of FIG. 1 .

As shown in FIG. 1 , the polyphase motor driving apparatus 100 according to an embodiment of the present invention includes an inverter 110 supplying driving power to the polyphase motor 200 , and each switch included in the inverter 110 . It includes a switching control unit 120 for controlling the turn-on-turn-off operation, and a fault detection unit 130 for detecting whether a switch corresponding to each phase current is faulty based on the phase current supplied to each phase of the polyphase electric motor 200 . .

In addition, although not shown in FIG. 1 , the polyphase motor driving device 100 is charged with the output of a converter (not shown) and a converter (not shown) that rectifies AC power input from the outside into DC power, and is charged to the inverter 110 . It may further include a DC link capacitor (not shown) for supplying DC power.

For example, the converter (not shown) may include a diode bridge including a plurality of diodes. The diode bridge rectifies AC power to output DC power.

In addition, the DC link capacitor (not shown) is connected in parallel between the output terminal of the converter (not shown) and the input terminal of the inverter 110 . By such a DC link capacitor (not shown), a ripple voltage due to an output of a converter (not shown) or a switching operation of switches included in the inverter 110 may be smoothed.

The inverter 110 converts the output of the DC link capacitor (not shown) into a polyphase AC power supply. The inverter 110 includes a plurality of switch units corresponding to the polyphase motor 200 .

For example, as shown in FIG. 2 , the inverter 110 includes five switch units 111 , 112 , 113 corresponding to different phases (a, b, c, d, e) of the five-phase electric motor 200 . , 114, 115) may be included.

Each switch unit 111 , 112 , 113 , 114 , 115 alternates a positive phase current, a negative phase current, and a zero phase current in each phase during each switch period to each phase of the electric motor 200 . can supply

To this end, each switch unit 111 , 112 , 113 , 114 , 115 corresponds to the upper switch SH1 , SH2 , SH3 , SH4 , SH5 corresponding to a positive phase current and a negative phase current corresponding to the top switch SH1 , SH2 , SH3 , SH4 , SH5 . It may include a lower switch (SL1, SL2, SL3, SL4, SL5).

As an example, when the DC link capacitor (not shown) is charged with Vdc, the first switch unit 111 among the plurality of switch units 111, 112, 113, 114, 115 includes the upper switch SH1 and the lower switch ( When all SL1) are turned off, the phase current (ia) of phase a is supplied to 0, and when the upper switch (SH1) is turned on and the lower switch (SL1) is turned off, the phase current (ia) of phase a is +Vdc/2 It is supplied with a positive sign corresponding to , and when the upper switch SH1 is turned off and the lower switch SL1 is turned on, the phase current ia of a phase is negative corresponding to -Vdc/2. Supplied with the sign of At this time, the counter electromotive force Ea generated in the a phase of the electric motor 200 corresponds to the phase current ia supplied to the a phase.

The second switch unit 112 corresponds to the b phase, the third switch unit 113 corresponds to the c phase, the fourth switch unit 114 corresponds to the d phase, and the fifth switch unit 115 corresponds to the d phase. Except for the point corresponding to the e-phase, the second, third, fourth, and fifth switch units 112 , 113 , 114 , 115 are the same as the first switch unit 111 , and thus redundant description will be omitted below. do.

In addition, the inverter 110 is disposed between the output terminal of each switch unit 111, 112, 113, 114, 115 and the motor 200, and the inductors L1, L2, L3, L4, L5) and resistors R1, R2, R3, R4, and R5 may be further included.

Again, Fig. 1 will be described next.

The polyphase motor 200 may include 2n rotor positions corresponding to n phases. Here, n is the number of phases of the polyphase motor 200 and the inverter 110 .

According to an embodiment of the present invention, for fault tolerance control, n may be a natural number exceeding three. For example, n may be 5 or 7.

As the polyphase motor 200 includes 2n rotor positions corresponding to n phases, each switching period may be made of 2n unit sections corresponding to 2n different rotor positions. Here, the switching period may correspond to a section in which the rotor position rotates once.

When the driving of the polyphase motor 200 is started and a failure of the inverter 100 is not detected, the switching control unit 120 operates the respective switch units 111, 112, 113, 114, and 115 of the inverter 110 in a normal driving mode. ) can be controlled.

At this time, the inverter 110 supplies driving power to the polyphase motor 200 in the (n-1)-phase energizing method by the switching control unit 120 in the normal driving mode.

The (n-1) phase energization method has a positive sign or a negative sign in the (n-1) phase corresponding to each rotor position among the n-phase motors 200 for each unit section corresponding to each rotor position. to supply phase current. That is, each rotor position corresponds to (n-1)/2 positive phase currents and (n-1)/2 negative phase currents supplied to the motor 200 during each unit section.

Accordingly, in the normal driving mode, each switch unit (111, 112, 113, 114, 115) supplies a positive phase current for consecutive (n-1) unit sections during each switch cycle, and then 0 for one unit section. A phase current is supplied, and a negative phase current is supplied for other consecutive (n-1) unit sections, and a phase current of 0 is supplied for one unit section thereafter.

In other words, the switching control unit 120 corresponds to each switch (SH1, SH2, SH3, SH4, SH5) (SL1, SL2, SL3, SL4, SL5) of the inverter 110 during each switching cycle according to the normal driving mode A turn-on signal is supplied to each of the switches SH1, SH2, SH3, SH4, and SH5 (SL1, SL2, SL3, SL4, SL5) of the inverter 110 during a predetermined first turn-on period. Here, the first turn-on period consists of consecutive (n-1) unit periods.

Accordingly, in the normal driving mode, each switch SH1, SH2, SH3, SH4, SH5 (SL1, SL2, SL3, SL4, SL5) of the inverter 110 is continuous (n-1) units during each switching period. It is turned on during the first turn-on period consisting of a period, and is turned off during the remaining (2n-(n-1)) unit periods.

Accordingly, in the normal driving mode, (n-1)/2 switches among the n switch units 111 , 112 , 113 , 114 , 115 included in the inverter 110 for each unit section corresponding to each rotor position. The upper switch of the negative part and the lower switch of the (n-1)/2 other switch parts are turned on, and the upper switch and the lower switch of the other switch part are turned off. For example, when n is 5, a positive phase current is supplied to two of the four phases corresponding to each rotor position from the inverter 110 during each unit period, and a negative phase current is supplied to the remaining two phases.

As such, when the phase currents of all phases are normal, the switching control unit 120 controls each switch SH1, SH2, SH3, SH4, SH5 (SL1, SL2, SL3, SL4, SL5) of the inverter 110 according to the normal driving mode. ) is turned on during the first turn-on period corresponding to each switch (SH1, SH2, SH3, SH4, SH5) (SL1, SL2, SL3, SL4, SL5) of each switching period, and is turned off during the remaining period.

On the other hand, the switching control unit 120, while controlling the inverter 110 in the normal driving mode, the failure detection unit 130 at least one switch included in the switch unit corresponding to any one phase of the inverter 110 as a failure. If detected, it switches to the fault tolerance mode for maintaining the motor operation regardless of at least one fault switch detected as a fault.

The fault detection unit 130 is based on the current value of each phase current transmitted from a current detector (not shown) disposed on a plurality of wires connecting the output terminal of the inverter 110 and the polyphase motor 200 to the inverter 110 . Detects failure of each switch SH1, SH2, SH3, SH4, SH5 (SL1, SL2, SL3, SL4, SL5).

For example, the failure detection unit 130 may detect a switch corresponding to a phase current in which a current value transmitted from the current detector is different from a predetermined current threshold range as a failure.

Alternatively, after deriving the terminal voltage value of the switch as the sum of the phase voltage and the neutral point voltage, the failure detection unit 130 may detect an open failure of the switch if the error between the terminal voltage value and the voltage command is greater than or equal to a threshold. (Non-patent literature: The Journal of Power Electronics Society, Volume 13, No. 6, December 2008, Paper 13-6-4, A Simple Switch Open Failure Detection Method of Voltage Source Inverter, by Kim Hakwon)

When the failure detection unit 130 detects as a failure at least one of the switches of the switch unit corresponding to any one phase of the electric motor 200 as a failure, the switching control unit 120 terminates the normal driving mode and switches to the failure tolerance mode do.

The switching control unit 120 turns off at least one faulty switch detected as a fault according to the fault tolerance mode. Accordingly, the at least one faulty switch is excluded from the switching operation control by the switching control unit 120 .

In addition, the switching control unit 120 may control the operation of each of the switch units 111 , 112 , 113 , 114 , and 115 of the inverter 110 except for at least one faulty switch according to the fault tolerance mode.

At this time, the inverter 110 supplies driving power to the polyphase motor 200 in the (n-3)-phase energizing method by the switching control unit 120 in the fault tolerance mode.

That is, the fault tolerance mode is a control mode in which driving power is supplied to the polyphase motor 200 in a (n-3)-phase energization method in which two phases are smaller than that of the general driving mode. Accordingly, since the number of windings of the phase having the opposite sign to the phase current by the faulty switch can be equal to the number of windings of the phase having the same sign as the phase current by the faulty switch, imbalance between phases due to the faulty switch can be prevented.

The (n-3) phase conduction method supplies a positive or negative phase current to (n-3) of the n-phase motor 200 for each unit section corresponding to each rotor position. That is, each rotor position corresponds to (n-3)/2 positive phase currents and (n-3)/2 negative phase currents supplied to the motor 200 during each unit section.

Accordingly, by the fault tolerance mode, each switch unit (111, 112, 113, 114, 115) supplies a positive phase current for consecutive (n-3) unit sections during each switch cycle, and then 0 for three unit sections. A phase current is supplied, and a negative phase current is supplied for other consecutive (n-3) unit sections, and a phase current of 0 is supplied for the next three unit sections.

In other words, the switching control unit 120 corresponds to each switch (SH1, SH2, SH3, SH4, SH5) (SL1, SL2, SL3, SL4, SL5) of the inverter 110 during each switching cycle according to the fault tolerance mode A turn-on signal is supplied to each of the switches SH1, SH2, SH3, SH4, and SH5 (SL1, SL2, SL3, SL4, SL5) of the inverter 110 during a predetermined second turn-on period. Here, the second turn-on period consists of consecutive (n-3) unit periods. That is, the second turn-on period according to the fault tolerance mode is shorter than the first turn-on period according to the normal driving mode.

Accordingly, in the fault tolerance mode, each switch (SH1, SH2, SH3, SH4, SH5) (SL1, SL2, SL3, SL4, SL5) of the inverter 110 is continuous (n-3) units during each switching cycle It is turned on during the second turn-on period consisting of a period, and is turned off during the remaining (2n-(n-3)) unit periods.

Accordingly, in the fault tolerance mode, (n-3)/2 switches among n switch units 111 , 112 , 113 , 114 , 115 included in the inverter 110 for each unit section corresponding to each rotor position The upper switch of the negative unit and the lower switch of (n-3)/2 other switch units are turned on, and the upper and lower switches of the remaining three switch units are turned off. For example, when n is 5, a positive phase current is supplied to one of the two phases corresponding to each rotor position from the inverter 110 and a negative phase current is supplied to the other phase during each unit period.

In addition, at least one faulty switch is maintained in a turned off state. Accordingly, when any one faulty switch corresponds to each rotor position, it is necessary to turn-on the replacement switch for supplying a phase current of the same sign as the phase current by the faulty switch instead of the turned-off faulty switch.

Accordingly, according to one embodiment of the present invention, the switching control unit 120 before controlling the inverter 110 according to the fault tolerance mode, each switch (SH1, SH2, SH3, SH4, SH5) included in the inverter (110) ) (SL1, SL2, SL3, SL4, SL5) derives the allowable replacement section, and switches (SH1, SH2, SH3, SH4, SH5) (SL1, SL2, SL3, SL4, SL5) included in the inverter 110 Select a replacement switch to replace each faulty switch based on their replacement allowable interval. Here, the replacement switch is a replacement allowable section in which each unit section included in the second turn-on section of each faulty switch does not correspond to the rotor position, and is selected as a switch supplying a phase current having the same sign as that of each faulty switch.

In addition, the switching control unit 120 maintains at least one faulty switch in the turned-off state during each switching cycle according to the fault tolerance mode, and replaces the replacement switch corresponding to each unit section of the second turn-on section of the turned-off faulty switch. A turn-on signal is supplied to

Such an alternative allowable section and an alternative switch will be described in detail below.

As described above, the polyphase motor driving apparatus 100 according to an embodiment of the present invention includes a failure detection unit 130 for detecting whether a switch for supplying a phase current to each phase of the electric motor 200 is faulty, and a failure detection unit 130 . ) includes a switching control unit 120 for switching to a failure tolerance mode when detecting at least one switch among the switches corresponding to any one phase as a failure. Accordingly, even if at least one switch among the switches corresponding to any one phase fails, the supply of driving power to the motor may be maintained by the inverter 110 controlled according to the failure tolerance mode. Accordingly, there is an advantage that the reliability of driving the electric motor 200 can be improved.

And, according to an embodiment of the present invention, when switching to the fault tolerance mode, the switching control unit 120 converts the inverter (n-3) into an (n-3)-phase energization method different from the (n-1)-phase energization method according to the normal driving mode. 110) to control each switch. In this way, inequality between phases due to any one faulty switch can be prevented.

That is, when the fault tolerance mode is a control mode in which driving power is supplied to the polyphase motor 200 in the same (n-1)-phase energized manner as in the general driving mode, the number of phase windings of the same sign as the phase current by the fault switch is It is smaller than the number of windings of the phase opposite to the phase current caused by the faulty switch. As a result, phase-to-phase imbalance may be caused, thereby generating current and torque pulsations. In addition, when the current and torque pulsations intensify, additional switch burnout may occur.

However, according to an embodiment of the present invention, the fault tolerance mode is a control mode in which driving power is supplied to the polyphase motor 200 in a (n-3)-phase energization method with two phases smaller than that of the general driving mode. The number of turns of the phase with the opposite sign to the phase current may be the same as the number of turns of the phase with the same sign as the phase current caused by the faulty switch. In addition, instead of maintaining the faulty switch in the turned-off state, an alternative switch capable of supplying the phase current by the faulty switch is turned on.

Thereby, since phase-to-phase imbalance can be prevented, current and torque pulsation due to phase-to-phase imbalance can be prevented. Thereby, further switch burnout can be prevented.

Further, according to an embodiment of the present invention, when switching from the normal driving mode to the fault tolerance mode, the (n-1) phase energization mode is switched to the (n-3) phase energization mode. At this time, since the torque ripple of the motor 200 is proportional to the number of energized phases, the torque ripple of the motor 200 is (1-(n-3)/(n-1)) at the time of switching to the fault tolerance mode. can be reduced.

Accordingly, according to an embodiment of the present invention, the reliability of the electric motor driving apparatus 100 can be further improved.

Next, a method of controlling an inverter of the electric motor driving apparatus 100 according to an embodiment of the present invention will be described with reference to FIGS. 3 to 11 .

3 is a view showing an inverter control method of a polyphase motor driving apparatus according to an embodiment of the present invention.

As shown in FIG. 3, the inverter control method according to an embodiment of the present invention includes the steps of driving the inverter according to the normal driving mode (S20), detecting whether a switch corresponding to each phase current is faulty (S30) , when at least one switch is detected as a failure (S40), supplying a turn-off signal to the failure switch detected as a failure, and switching to a failure tolerance mode (S50), and driving the inverter according to the failure tolerance mode (S60).

And, the inverter control method includes the steps of deriving a replacement allowable section of the phase current by each switch before the step (S60) of driving the inverter according to the fault tolerance mode (S70), and detecting at least one faulty switch (S40) The method may further include a step (S80) of selecting a replacement switch in place of at least one faulty switch based on the replacement allowable section of the phase current by each switch.

Specifically, when the driving of the electric motor 200 is started (S10), the switching control unit 120 drives the inverter 110 according to the normal driving mode. (S20) At this time, the switching control unit 120 controls each switch SH1, SH2, SH3, SH4, SH5 (SL1, SL2, SL3, SL4, SL5) of the inverter 110 according to the normal driving mode during each switching cycle. It is turned on during a predetermined first turn-on period corresponding to each switch of the inverter 110 .

Specifically, the switching control unit 120 drives the inverter 110 in the (n-1)-phase energization method according to the normal driving mode.

FIG. 4 is a diagram illustrating an example of phase current and counter electromotive force of each phase when the inverter of FIG. 2 is driven in a normal driving mode.

As shown in FIG. 4 , when the polyphase motor 200 includes 2n rotor positions corresponding to n phases, each switching period SP has 2n unit sections ( UP1, UP2, UP3, UP4, UP5, UP6, UP7, UP8, UP9, UP10). For example, when the polyphase motor 200 is five-phase (n=5), each switching period SP has 10 unit sections (UP1, UP2, UP3, UP4, UP5, UP6, UP7, UP8, UP9, UP10) is made of

Due to the (n-1)-phase energization method according to the normal driving mode, the first turn-on period (TP11, TP12, TP21, TP22, TP31, TP32, TP41, TP42, TP51, TP52) corresponding to each switch of the inverter 110 ) consists of consecutive (n-1) unit sections.

For example, the first turn-on section TP11 of the upper switch SH1 among the first switch units ( 111 in FIG. 2 ) corresponding to the a phase of the electric motor 200 includes first, second, third and fourth units. It consists of sections UP1, UP2, UP3, UP4, and the first turn-on section TP12 of the lower switch SL1 has the sixth, seventh, eighth and ninth unit sections UP6, UP7, UP8, UP9. is made of In addition, during the fifth and tenth unit periods UP5 and UP10 disposed between the upper switch SH1 of the first switch unit 111 and the first turn-on period TP11 of the lower switch SL1, the first switch unit The upper switch SH1 and the lower switch SL1 of (111) are turned off.

At this time, the positive phase current ia supplied to the a phase of the motor 200 during the first turn-on period TP11 (UP1 to UP4) of the upper switch SH1 of the first switch unit 111 during each switching period SP >0), the back electromotive force (Ea) of phase a has a slope of zero and a positive sign.

On the other hand, during the first turn-on period (TP12; UP6 to UP9) of the lower switch SL1 of the first switch unit 111 during each switching period SP, the negative phase current ia supplied to the a phase of the motor 200 <0), the back electromotive force (Ea) of phase a has a slope of 0 and a negative sign.

In addition, the fifth and tenth units disposed between the first turn-on sections TP11 and TP12 of the upper switch SH1 and the lower switch SL1 of the first switch unit 111 during each switching period SP Since the upper switch SH1 and the lower switch SL1 of the first switch unit 111 are turned off during the sections UP5 and UP10, the phase current ia of the a phase of the electric motor 200 is maintained at 0, and the phase a The back electromotive force Ea varies with a non-zero slope.

As another example, during the first turn-on period (TP21; UP3 to UP6) of the upper switch (SH2) of the second switch unit (112 in FIG. 2) corresponding to the b-phase of the electric motor 200 during each switching period (SP) Due to the positive phase current (ib>0) supplied to the b-phase of the electric motor 200, the b-phase counter electromotive force Eb has a slope of 0 and a positive (+) sign.

During the first turn-on period TP22 (UP8 to UP10, UP1) of the lower switch SL2 of the second switch unit 112 during each switching period SP, the negative phase current ib supplied to the b phase of the motor 200 <0), the back electromotive force (Eb) of phase b has a slope of zero and a negative sign.

The second and seventh unit sections disposed between the first turn-on sections TP21 and TP22 of the upper switch SH2 and the lower switch SL2 of the second switch unit 112 during each switching period SP ( Since the upper switch SH2 and the lower switch SL2 of the second switch unit 112 are turned off during UP2, UP7), the phase current ib of the phase b of the electric motor 200 is maintained at 0, and the counter electromotive force of the phase b Eb) varies with a non-zero slope.

Similarly, during the first turn-on period (TP31; UP5 to UP8) of the upper switch (SH3) of the third switch unit (113 in FIG. 2) corresponding to the c-phase of the electric motor 200 during each switching period (SP) 200), a positive phase current (ic>0) is supplied to phase c.

During the first turn-on period (TP32; UP10, UP1 to UP3) of the lower switch SL3 of the third switch unit 113 during each switching period SP, a negative phase current (ic<0) in the c phase of the motor 200 ) is supplied.

The fourth and ninth unit sections disposed between the first turn-on sections TP31 and TP32 of the upper switch SH3 and the lower switch SL3 of the third switch unit 113 during each switching period SP Since the upper switch SH3 and the lower switch SL3 of the third switch unit 113 are turned off during UP4 and UP9), a zero phase current (ic=0) is supplied to the c phase of the electric motor 200 .

During the first turn-on period (TP41; UP7 to UP10) of the upper switch (SH4) of the fourth switch unit (114 in FIG. 2) corresponding to the d phase of the electric motor 200 during each switching period (SP), the electric motor 200 A positive phase current (id>0) is supplied to the d phase of

During the first turn-on period (TP42; UP2 to UP5) of the lower switch SL4 of the fourth switch unit 114 during each switching period SP, the negative phase current (id<0) in the d phase of the motor 200 is is supplied

The first and sixth unit sections disposed between the first turn-on sections TP41 and TP42 of the upper switch SH4 and the lower switch SL4 of the fourth switch unit 114 during each switching period SP Since the upper switch SH4 and the lower switch SL4 of the fourth switch unit 114 are turned off during UP1 and UP6 , a zero phase current (id=0) is supplied to the d phase of the electric motor 200 .

During the first turn-on period (TP51; UP9, UP10, UP1, UP2) of the upper switch (SH5) of the fifth switch unit (115 in FIG. 2) corresponding to the e-phase of the electric motor 200 during each switching period (SP) A positive phase current (ie>0) is supplied to phase e of the electric motor 200 .

During the first turn-on period (TP52; UP4 to UP7) of the lower switch (SL5) of the fifth switch unit 115 during each switching period (SP), the negative phase current (ie<0) in the e-phase of the electric motor 200 (ie<0) is supplied

The third and eighth unit sections disposed between the first turn-on sections TP51 and TP52 of the upper switch SH5 and the lower switch SL5 of the fifth switch unit 115 during each switching period SP Since the upper switch SH5 and the lower switch SL5 of the fifth switch unit 115 are turned off during UP3 and UP8 , a zero phase current (ie = 0) is supplied to the e phase of the electric motor 200 .

As such, according to the general driving mode, each rotor position of the five-phase electric motor 200 corresponds to a positive phase current supplied to two phases and a negative phase current supplied to the other two phases during each unit period. To this end, during each unit period UP, the upper switch SH of the two switch units corresponding to each rotor position and the lower switch SL of the other two switch units are turned on.

That is, the switching control unit 120 alternately selects 10 rotor positions during each switching period SP in order to rotate the rotor of the five-phase motor 200 . At this time, according to the (n-1) phase conduction method corresponding to the general driving mode, two (=(n-1)/2) positive phase currents and two ( =(n-1)/2), the upper switch SH of the two switch parts and the lower switch SL of the other two switch parts are turned on to supply a negative phase current.

Meanwhile, while the electric motor 200 is being driven, at least one switch among the switches of the inverter 110 may be open-failed.

FIG. 5 is a diagram illustrating an example of an equivalent circuit of an inverter corresponding to the second unit section of FIG. 4 when the upper end switch of the first switch unit corresponding to the phase a of the inverters of FIG. 2 is faulty.

5, during the second unit period UP2, positive phase currents are supplied to phase a and e, and negative phase currents are supplied to phases c and d.

However, when the upper switch SH1 of the first switch unit 111 for supplying the positive phase current to the a phase is faulty, the winding corresponding to the positive phase current is only the phase e except for the faulty phase a, whereas the negative phase current is the same. The windings corresponding to the phase currents of are c-phase and d-phase. Accordingly, an imbalance between the phases is caused.

In order to prevent this, in the inverter control method according to an embodiment of the present invention, when at least one switch corresponding to any one phase is detected as a failure (S40 in FIG. 3 ), at least one failure switch detected as a failure It includes the steps of supplying a turn-off signal and switching to the fault tolerance mode (S50) and driving the inverter according to the fault tolerance mode (S60).

Specifically, when the fault detection unit 130 detects at least one switch corresponding to any one phase as a fault switch (S40), the switching control unit 120 supplies a turn-off signal to the detected at least one fault switch. do. Then, the switching control unit 120 switches to the fault tolerance mode. (S50)

The switching control unit 120 controls each switch SH1, SH2, SH3, SH4, SH5 (SL1, SL2, SL3, SL4, SL5) of the inverter 110 according to the fault tolerance mode in the first turn-on section according to the normal driving mode. It is turned on during the shorter second turn-on period. (S60)

FIG. 6 is a diagram illustrating an example of phase current and counter electromotive force of each phase when each switch of the inverter of FIG. 2 is turned on during a second turn-on period smaller than the first turn-on period according to the normal driving mode.

As shown in FIG. 6 , each switching period SP has 2n unit sections UP1, UP2, UP3, UP4, UP5, UP6, UP7, UP8, UP9, UP10).

The switching control unit 120 drives the inverter 110 in a (n-3)-phase energized manner according to the fault tolerance mode. That is, in the fault tolerance mode, compared to the (n-1)-phase energization method according to the general drive mode, the inverter 110 is driven by the (n-3)-phase energization method in which two phases are energized during each unit section. is the mode

And, due to the (n-3) phase energization method according to the fault tolerance mode, corresponding to each switch (SH1, SH2, SH3, SH4, SH5) (SL1, SL2, SL3, SL4, SL5) of the inverter 110 The second turn-on sections TP11', TP12', TP21', TP22', TP31', TP32', TP41', TP42', TP51', TP52' consist of consecutive (n-3) unit sections.

For example, during the second turn-on period (TP11'; UP2, UP3) of the upper switch (SH1) of the first switch unit (111 in FIG. 2) corresponding to the a-phase of the electric motor 200 during each switching period (SP) A positive phase current (ia>0) is supplied to phase a of the electric motor 200 .

During the second turn-on period (TP12'; UP7, UP8) of the lower end switch SL1 of the first switch unit 111 during each switching period SP, a negative phase current (ia<0) in the a phase of the motor 200 is supplied

4th, 5th, and 6th disposed between the first turn-on sections TP11 and TP12 of the upper switch SH1 and the lower switch SL1 of the first switch unit 111 during each switching period SP , ninth, tenth and first unit sections UP4, UP5, UP6 (UP9, UP10, UP1), a phase current of zero (ia=0) is supplied to a phase of the motor 200 .

During the second turn-on period (TP21'; UP4, UP5) of the upper switch (SH2) of the second switch unit (112 in FIG. 2) corresponding to the b-phase of the electric motor 200 during each switching period (SP), the motor 200 ), a positive phase current (ib>0) is supplied to phase b.

During the second turn-on period (TP22'; UP9, UP10) of the lower switch (SL2) of the second switch unit 112 during each switching period (SP), a negative phase current (ib<0) in the b phase of the motor 200 is supplied

First, second, and third positions disposed between the first turn-on sections TP21 and TP22 of the upper switch SH2 and the lower switch SL2 of the second switch unit 112 during each switching period SP , during the sixth, seventh and eighth unit sections UP1 to UP3 (UP6 to UP8), a phase current of zero (ib=0) is supplied to phase b of the electric motor 200 .

During the second turn-on period (TP31'; UP6, UP7) of the upper switch (SH3) of the third switch unit (113 in FIG. 2) corresponding to the c-phase of the electric motor 200 during each switching period (SP), the motor 200 ), a positive phase current (ic > 0) is supplied to phase c.

During the second turn-on period (TP32'; UP1, UP2) of the lower end switch SL3 of the third switch unit 113 during each switching period SP, a negative phase current (ic<0) in the c phase of the motor 200 is supplied

Third, fourth, and fifth disposed between the first turn-on sections TP31 and TP32 of the upper switch SH3 and the lower switch SL3 of the third switch unit 113 during each switching period SP , during the eighth, ninth and tenth unit sections UP3 to UP5 (UP8 to UP10), a zero phase current (ic=0) is supplied to the c phase of the motor 200 .

During the second turn-on period (TP41'; UP8, UP9) of the upper switch (SH4) of the fourth switch unit (114 in FIG. 2) corresponding to the d phase of the electric motor 200 during each switching period (SP), the motor 200 ), a positive phase current (id>0) is supplied to phase d.

During the second turn-on period (TP42'; UP3, UP4) of the lower end switch SL4 of the fourth switch unit 114 during each switching period SP, a negative phase current (id<0) in the d phase of the motor 200 is supplied

5th, 6th, and 7th disposed between the first turn-on sections TP41 and TP42 of the upper switch SH4 and the lower switch SL4 of the fourth switch unit 114 during each switching period SP , a phase current of 0 (id=0) is supplied to phase d of the motor 200 during the tenth, first and second unit sections UP5 to UP7 (UP10, UP1, UP2).

During the second turn-on period (TP51'; UP10, UP1) of the upper switch (SH5) of the fifth switch unit (115 in FIG. 2 ) corresponding to the e-phase of the electric motor 200 during each switching period (SP), the motor 200 ), a positive phase current (ie > 0) is supplied to phase e.

During the second turn-on period (TP52'; UP5, UP6) of the lower switch (SL5) of the fifth switch unit 115 during each switching period (SP), the negative phase current (ie < 0) in the e-phase of the motor 200 is supplied

Seventh, eighth, ninth disposed between the first turn-on sections TP51 (TP52) of the upper switch SH5 and the lower switch SL5 of the fifth switch unit 115 during each switching period SP , a phase current of zero (ie = 0) is supplied to phase e of the electric motor 200 during the second, third and fourth unit sections UP7 to UP9 (UP2 to UP4).

As such, according to the fault tolerance mode, each rotor position of the five-phase motor 200 corresponds to a positive phase current supplied to one phase and a negative phase current supplied to the other phase during each unit period. To this end, during each unit section UP, one upper switch SH and one lower switch SL corresponding to each rotor position are turned on.

That is, the switching control unit 120 alternately selects 10 rotor positions during each switching period SP in order to rotate the rotor of the five-phase motor 200 . At this time, according to the (n-3) phase energization method corresponding to the fault tolerance mode, one (=(n-3)/2) positive phase current and two ( =(n-3)/2), the upper switch SH of one switch part and the lower switch SL of the other switch part are turned on to supply a negative phase current.

In addition, since the second turn-on section according to the fault tolerance mode is shorter than the first turn-on section according to the normal drive mode, each switch SH1, SH2, SH3, SH4, based on the difference between the first turn-on section and the second turn-on section SH5) (SL1, SL2, SL3, SL4, SL5) alternative allowable interval can be derived.

Accordingly, the switching control unit 120 replaces the phase current by each switch (SH1, SH2, SH3, SH4, SH5) (SL1, SL2, SL3, SL4, SL5) before the step (S50) of switching to the fault tolerance mode. Derive the allowable interval. (S70)

FIG. 7 is a diagram showing an example of an allowable replacement period of a phase current by each switch in the inverter of FIG. 2 .

As shown in Figure 7, in the fault tolerance mode, only the second turn-on section according to the (n-3) phase energization method corresponds to each rotor position, but the n-phase motor 200 is -1) It can also be driven by a phase energization method. Accordingly, the difference between the unit section included in the first turn-on section but not included in the second turn-on section, that is, the first turn-on section and the second turn-on section, does not correspond to each rotor position in the (n-3) phase energization method. Therefore, it can be used as an alternative allowable section to supply the phase current by the faulty switch instead.

Here, the first turn-on section according to the (n-1)-phase energization method includes a second turn-on section according to the (n-3)-phase energization method and two unit sections disposed at both ends of the second turn-on section. Accordingly, the difference between the first turn-on period and the second turn-on period may be derived as two unit periods disposed at both ends of the second turn-on period.

That is, each switch (SH1, SH2, SH3, SH4, SH5) (SL1, SL2, SL3, SL4, SL5) is allowed replacement period (RP11, RP21, RP31, RP32, RP41, RP42, RP51, RP52; Replacement Period) may be derived as two unit sections disposed at both ends of the second turn-on section of each switch SH1 , SH2 , SH3 , SH4 , SH5 ( SL1 , SL2 , SL3 , SL4 , SL5 ).

For example, the allowable replacement section RP11 of the upper switch SH1 of the first switch unit 111 is the second turn-on section TP11' of the upper switch SH1 of the first switch unit 111; UP2, UP3) The first and fourth unit sections UP1 and UP2 disposed at both ends of are derived. Accordingly, the upper switch SH1 of the first switch unit 111 may be selected as an alternative switch for supplying a positive phase current instead of the faulty switch during the first unit period UP1 or the fourth unit period UP2.

The replacement allowable section RP12 of the lower end switch SL1 of the first switch unit 111 is at both ends of the second turn-on section TP12' of the lower end switch SL1 of the first switch unit 111; UP7, UP8. It is derived from the arranged sixth and ninth unit sections UP6 and UP9. Accordingly, the lower switch SL1 of the first switch unit 111 may be selected as an alternative switch for supplying a negative phase current instead of the faulty switch during the sixth unit period UP6 or the ninth unit period UP9.

The replacement allowable section RP21 of the upper switch SH2 of the second switch unit 112 is at both ends of the second turn-on section TP21' of the upper switch SH2 of the second switch unit 112; UP4, UP5. It is derived from the arranged third and sixth unit sections UP3 and UP6. Accordingly, the upper switch SH2 of the second switch unit 112 may be selected as an alternative switch for supplying a positive phase current instead of the faulty switch in at least one of the third and sixth unit sections UP3 and UP6.

And, the allowable replacement section RP22 of the lower end switch SL2 of the second switch unit 112 is the second turn-on section TP22' of the lower end switch SL2 of the second switch unit 112; UP9, UP10. It is derived from the eighth and first unit sections UP8 and UP1 disposed at both ends. Accordingly, the lower switch SL2 of the second switch unit 112 may be selected as an alternative switch for supplying a negative phase current instead of the faulty switch in at least one of the eighth and first unit sections UP8 and UP1.

The replacement allowable section RP31 of the upper switch SH3 of the third switch unit 113 is at both ends of the second turn-on section TP31' of the upper switch SH3 of the third switch unit 113; UP6, UP7. It is derived from the arranged fifth and eighth unit sections UP5 and UP8. Accordingly, the upper switch SH3 of the third switch unit 113 may be selected as an alternative switch for supplying a positive phase current instead of the faulty switch in at least one of the fifth and eighth unit sections UP5 and UP8.

And, the replacement allowable section (RP32) of the lower end switch (SL3) of the third switch unit 113 is the second turn-on section (TP32'; UP1, UP2) of the lower end switch (SL3) of the third switch unit 113 It is derived from the tenth and third unit sections UP10 and UP3 disposed at both ends. Accordingly, the lower switch SL3 of the third switch unit 113 may be selected as an alternative switch for supplying a negative phase current instead of the faulty switch in at least one of the tenth and third unit sections UP10 and UP3.

The replacement allowable section RP41 of the upper switch SH4 of the fourth switch unit 114 is at both ends of the second turn-on section TP41' of the upper switch SH4 of the fourth switch unit 114; UP8, UP9. It is derived from the arranged seventh and tenth unit sections UP7 and UP10. Accordingly, the upper switch SH4 of the fourth switch unit 114 may be selected as an alternative switch for supplying a positive phase current instead of the faulty switch in at least one of the seventh and tenth unit sections UP7 and UP10.

And, the replacement allowable section (RP42) of the lower switch (SL4) of the fourth switch unit 114 is the second turn-on section (TP42'; UP3, UP4) of the lower switch (SL4) of the fourth switch unit 114 It is derived from the second and fifth unit sections UP2 and UP5 disposed at both ends. Accordingly, the lower switch SL4 of the fourth switch unit 114 may be selected as an alternative switch for supplying a negative phase current instead of the faulty switch in at least one of the second and fifth unit sections UP2 and UP5.

The replacement allowable section RP51 of the upper switch SH5 of the fifth switch unit 115 is at both ends of the second turn-on section TP51' of the upper switch SH5 of the fifth switch unit 115; UP10, UP1. It is derived from the arranged ninth and second unit sections UP9 and UP2. Accordingly, the upper switch SH5 of the fifth switch unit 115 may be selected as a replacement switch for supplying a positive phase current instead of the faulty switch in at least one of the ninth and second unit sections UP9 and UP2.

And, the replacement allowable section (RP52) of the lower switch (SL5) of the fifth switch unit 115 is the second turn-on section (TP42'; UP5, UP6) of the lower switch (SL5) of the fifth switch unit 115 It is derived from fourth and seventh unit sections UP4 and UP7 disposed at both ends. Accordingly, the lower switch SL5 of the fifth switch unit 115 may be selected as an alternative switch for supplying a negative phase current instead of the faulty switch in at least one of the fourth and seventh unit sections UP4 and UP7.

Then, the switching control unit 120 when at least one faulty switch is derived among the switches corresponding to any one phase (S40), the switches (SH1, SH2, SH3, SH4, SH5) included in the inverter 110 (SH1, SH2, SH3, SH4, SH5) Based on the allowable replacement section (RP11, RP21, RP31, RP32, RP41, RP42, RP51, RP52) of (SL1, SL2, SL3, SL4, SL5), the phase current by each fault switch and the second turn-on of each fault switch Select an alternative switch of any one allowable replacement section corresponding to each unit section included in the section. (S80)

As an example, a case in which the upper switch SH1 of the first switch unit 111 supplying a positive phase current (ia>0) to phase a is detected as a faulty switch will be described.

8 is a view showing an example of the phase current and counter electromotive force of each phase according to the fault tolerance mode when the upper switch of the first switch unit corresponding to the phase a of the inverter of FIG. 2 is faulty. And, FIG. 9 is a diagram showing an example of an equivalent circuit corresponding to the second unit section of FIG. 8 in the inverter of FIG. 2 .

As shown in FIG. 8 , when the upper switch SH1 of the first switch unit 111 is detected as a faulty switch, the upper switch SH1 of the first switch unit 111 operates during each switching period SP. remains turned off.

Accordingly, as in the second turn-on period TP11', even if the upper switch SH1 of the first switch unit 111 corresponds to the rotor position, it is impossible to supply the positive phase current (ia>0) to the a phase. Do.

Accordingly, when the upper switch SH1 of the first switch unit 111 detected as a failure corresponds to the rotor position, the switching control unit 120 controls the upper end of the switch SH1 of the first switch unit 111. The replacement switch corresponding to each unit period UP2 and UP3 included in the second turn-on period TP11' is turned on.

Here, the replacement switch corresponding to the second unit section UP2 among the second turn-on sections TP11 ′ of the upper switch SH1 of the first switch unit 111 is located at the rotor position of the second unit section UP2 . The upper switch SH5 of the fifth switch unit 115 that does not correspond to and provides any one replacement allowable section RP51 that supplies a positive phase current in the same way as the upper switch SH1 of the first switch unit 111 ) is selected.

And, the replacement switch corresponding to the third unit period UP3 among the second turn-on period TP11' of the upper switch SH1 of the first switch unit 111 is in the positive phase current with the third unit period UP3. It is selected as the upper switch (SH2) of the second switch unit 112 that provides the corresponding replacement allowable section (RP21).

Accordingly, as shown in FIG. 9 , the positive phase current is supplied to the e phase instead of the a phase during the second unit period UP2 .

As another example, a case in which the lower end switch SL4 of the fourth switch unit 114 that supplies a negative phase current (id<0) to the d phase is detected as a faulty switch will be described.

10 is a view showing an example of the phase current and counter electromotive force of each phase according to the fault tolerance mode when the upper switch of the first switch unit corresponding to the phase a of the inverter of FIG. 2 is faulty.

As shown in FIG. 10 , when the lower end switch SL4 of the fourth switch unit 114 is detected as a faulty switch, the lower end switch SL4 of the fourth switch unit 114 operates during each switching period SP. remains turned off. Therefore, like the third and fourth unit sections UP3 and UP4, even if the lower switch SL4 of the fourth switch unit 114 corresponds to the rotor position, the negative phase current id < 0 for the d phase supply is not possible.

Instead, during each unit period UP3 and UP4 included in the second turn-on period TP42' of the lower end switch SL4 of the fourth switch unit 114, the lower end switch SL4 of the fourth switch unit 114 ) and turn on the corresponding replacement switch.

Here, the replacement switch corresponding to the third unit section UP3 of the second turn-on section TP42' of the lower switch SL4 of the fourth switch unit 114 is located at the rotor position in the third unit section UP3. The lower end switch SL3 of the third switch unit 113 that does not correspond to and provides any one alternative allowable section RP32 for supplying a negative phase current in the same way as the lower switch SL4 of the fourth switch unit 114 . ) is selected. Accordingly, instead of the lower switch SL4 of the fourth switch unit 114 during the third unit period UP3 of the second turn-on period TP42 ′ corresponding to the lower end switch SL4 of the fourth switch unit 114 . The lower switch SL3 of the third switch unit 113 is turned on.

Similarly, the replacement switch corresponding to the fourth unit period UP4 in the second turn-on period TP42' of the lower switch SL4 of the fourth switch unit 114 generates a negative phase current during the fourth unit period UP4. It is selected as the lower switch SL5 of the fifth switch unit 115 that provides the replacement allowable section RP52 to be supplied. Accordingly, instead of the lower switch SL4 of the fourth switch unit 114 during the fourth unit period UP4 of the second turn-on period TP42 ′ corresponding to the lower end switch SL4 of the fourth switch unit 114 . The lower switch SL5 of the fifth switch unit 115 is turned on.

As described above, according to an embodiment of the present invention, instead of the faulty switch maintained in the turn-off state in the fault tolerant mode, the replacement switch selected to replace the faulty switch is turned on. Accordingly, the motor driving can be maintained regardless of the faulty switch. Therefore, the reliability of driving the electric motor can be improved.

On the other hand, according to an embodiment of the present invention, it is possible to provide a failure tolerance mode even when both the upper and lower switches of the switch unit corresponding to any one phase are detected as failures.

As an example, a case in which the upper switch SH2 and the lower switch SL2 of the second switch unit 112 corresponding to the phase b are detected as malfunctions will be described.

11 is a view showing an example of the phase current and counter electromotive force of each phase according to the fault tolerance mode when both the upper and lower switches of the second switch unit corresponding to the b phase of the inverter of FIG. 2 are faulty.

11, when the upper switch (SH2) and the lower switch (SL2) of the second switch unit 112 are detected as faulty switches, the upper switch (SH2) and the lower end of the second switch unit 112 All switches SL2 are maintained in a turned-off state during each switching period SP.

And, the upper switch (SH2) of the second switch unit 112, which is a faulty switch, is connected to each of the fourth and fifth unit sections (UP4) during the fourth and fifth unit sections (UP4, UP5) corresponding to the rotor position. The replacement switch providing the replacement allowable section (RP11, RP31) corresponding to the positive phase current is turned on.

Here, the replacement switch corresponding to the positive phase current and the fourth unit section UP4 by the upper switch SH2 of the second switch unit 112 is selected as the upper switch SH1 of the first switch unit 111 and , an alternative switch corresponding to the positive phase current by the upper switch SH2 of the second switch unit 112 and the fifth unit section UP5 is selected as the upper switch SH3 of the third switch unit 113 .

In addition, during the ninth and tenth unit sections UP9 and UP10 corresponding to the rotor position, the lower switch SL2 of the second switch unit 112, which is a faulty switch, the ninth and tenth unit sections UP9 and UP10. Alternative switches providing alternate allowable sections (RP12, RP32) corresponding to each and negative phase current are turned on.

Here, an alternative switch corresponding to the negative phase current by the lower end switch SL2 of the second switch unit 112 and the ninth unit section UP9 is selected as the lower end switch SL1 of the first switch unit 111 and , an alternative switch corresponding to the negative phase current by the lower end switch SL2 of the second switch unit 112 and the tenth unit section UP10 is selected as the lower end switch SL3 of the third switch unit 113 .

As described above, according to an embodiment of the present invention, even if both the upper switch and the lower switch included in the switch unit corresponding to any one phase fail, the failure tolerance mode can be provided. Therefore, the reliability of driving the electric motor can be further improved.

In addition, although not shown separately, in the inverter control method according to an embodiment of the present invention, in case the upper switch and the lower switch included in the switch unit corresponding to any one phase are not detected as failures at the same time, the failure After the step of driving the inverter according to the permissible mode, the step of detecting whether each switch is faulty, and when a switch corresponding to the same phase as the faulty switch is further detected as a fault, the fault tolerant mode for the switch unit detected as a fault It may further include the step of driving the inverter according to the.

The motor driving apparatus according to an embodiment of the present invention described above is presented as an example of driving a five-phase motor. However, an embodiment of the present invention is not limited to a 5-phase motor, and may be applied to a 7-phase motor.

12 is a view showing another example of an equivalent circuit of the inverter and the polyphase motor of FIG. 1 .

12, the inverter 110' and the polyphase motor 200' of the motor driving device according to another embodiment of the present invention have 7-phase (a, b, c, d, e, f, g) ), since it is the same as the embodiment shown in FIG. 2 , a redundant description will be omitted below.

The inverter 110 ′ includes seven switch units 111 , 112 , 113 , 114 , 115 , 116 , and 117 corresponding to different phases of the seven-phase motor 200 ′. Each switch unit includes upper switches (SH1, SH2, SH3, SH4, SH5, SH6, SH7) and lower switches (SL1, SL2, SL3, SL4, SL5, SL6, SL7).

When the driving of the motor 200 is started (S10), the switching control unit 120 drives the inverter 110' according to the normal driving mode. (S20) At this time, the switching control unit 120 drives the inverter 110' in the (n-1)-phase energization method according to the normal driving mode.

13A and 13B are diagrams illustrating an example of phase current and counter electromotive force of each phase when the inverter of FIG. 12 is driven in a normal driving mode.

13A and 13B, when the polyphase motor 200' has 7 phases (n=7), each switching period SP has 14 (=2n) unit sections UP1, UP2, UP3, UP4. , UP5, UP6, UP7, UP8, UP9, UP10, UP11, UP12, UP13, UP14).

In the (n-1)-phase energization method according to the general driving mode, the position of each rotor of the 7-phase motor 200 is the positive phase current supplied to three phases during each unit section and the negative phase current supplied to the other three phases during each unit section. Corresponds to the phase current. To this end, during each unit period UP, the upper switch SH of the three switch units corresponding to each rotor position and the lower switch SL of the other three switch units are turned on.

Accordingly, each switch (SH1, SH2, SH3, SH4, SH5, SH6, SH7) (SL1, SL2, SL3, SL4, SL5, SL6, SL7) of the inverter 110' by the switching control unit 120 in the normal driving mode ) corresponding to the first turn-on period (TP11, TP12, TP21, TP22, TP31, TP32, TP41, TP42, TP51, TP52, TP61, TP62, TP71, TP72) has 6 (=n-1) consecutive unit sections is made of

Subsequently, when the failure detection unit 130 detects at least one switch corresponding to any one phase as a failure switch (S40), the switching control unit 120 supplies a turn-off signal to the detected at least one failure switch. . Then, the switching control unit 120 switches to the fault tolerance mode. (S50)

At this time, the switching control unit 120 drives the inverter 110' in the (n-3)-phase energization method according to the failure driving mode.

14A and 14B are diagrams illustrating an example of the phase current and counter electromotive force of each phase when each switch of the inverter of FIG. 12 is turned on during a second turn-on period smaller than the first turn-on period according to the normal driving mode.

14A and 14B, in the (n-3)-phase energization method according to the fault tolerance mode, each rotor position of the 7-phase motor 200 is the amount of the amount supplied to the two phases during each unit section. It corresponds to the negative phase current supplied to the two phases different from the phase current. To this end, during each unit period UP, the upper switch SH of the two switch units corresponding to each rotor position and the lower switch SL of the other two switch units are turned on.

Accordingly, in the (n-3) phase energization method according to the fault tolerance mode, each switch (SH1, SH2, SH3, SH4, SH5, SH6, SH7) (SL1, SL2, SL3, SL4, SL5) of the inverter 110' , SL6, SL7) corresponding to the second turn-on section (TP11', TP12', TP21', TP22', TP31', TP32', TP41', TP42', TP51', TP52', TP61', TP62', TP71 ', TP72') consists of 4 (=n-3) consecutive unit sections.

As such, since the second turn-on section by the (n-3)-phase energization method according to the fault tolerance mode is shorter than the first turn-on section by the (n-1)-phase energization method according to the general drive mode, the first turn-on section On the basis of the difference between the second turn-on period and each switch (SH1, SH2, SH3, SH4, SH5, SH6, SH7) (SL1, SL2, SL3, SL4, SL5, SH6, SH7), the replacement allowable period of the phase current is can be derived. (S70)

15A and 15B are diagrams illustrating an example of an allowable replacement section of a phase current by each switch in the inverter of FIG. 12 .

15A and 15B, the difference between the unit section included in the first turn-on section but not included in the second turn-on section, that is, the first turn-on section and the second turn-on section, is the (n-3) phase energization method Since it does not correspond to each rotor position in , it can be used as an alternative allowable section to supply the phase current by the faulty switch instead.

That is, each switch (SH1, SH2, SH3, SH4, SH5, SH6, SH7) (SL1, SL2, SL3, SL4, SL5, SH6, SH7) of the allowable replacement section (RP11, RP21, RP31, RP32, RP41, RP42) , RP51, RP52, RP61, RP62, RP71, RP72) each switch (SH1, SH2, SH3, SH4, SH5) (SL1, SL2, SL3, SL4, SL5) of the second turn-on period (TP11', TP12', TP21', TP22', TP31', TP32', TP41', TP42', TP51', TP52', TP61', TP62', TP71', TP72')) .

As an example, the allowable replacement section RP11 of the upper switch SH1 of the first switch unit 111 corresponding to the phase current ia of the a phase is the second turn-on of the upper switch SH1 of the first switch unit 111 . It is derived from the first and sixth unit sections UP1 and UP6 disposed at both ends of the section TP11'; UP2, UP3, UP4, and UP5. Accordingly, the upper switch SH1 of the first switch unit 111 may be selected as an alternative switch for supplying a positive phase current instead of the faulty switch in at least one of the first and sixth unit sections UP1 and UP6.

The replacement allowable section RP12 of the lower end switch SL1 of the first switch unit 111 is the second turn-on section TP12' of the lower end switch SL1 of the first switch unit 111; UP9, UP10, UP11, UP12 ) is derived from the eighth and thirteenth unit sections UP8 and UP13 disposed at both ends of the . Accordingly, the lower switch SL1 of the first switch unit 111 may be selected as an alternative switch for supplying a negative phase current instead of the faulty switch during the eighth unit period UP8 or the thirteenth unit period UP13.

The allowable replacement section RP21 of the upper switch SH2 of the second switch unit 112 corresponding to the phase current ib of the b phase is the second turn-on section TP21 of the upper switch SH2 of the second switch unit 112. '; UP4, UP5, UP6, and UP7 are derived from the third and eighth unit sections UP3 and UP8 disposed at both ends. Accordingly, the upper switch SH2 of the second switch unit 112 may be selected as an alternative switch for supplying a positive phase current instead of the faulty switch in at least one of the third and eighth unit sections UP3 and UP8.

The replacement allowable section RP22 of the lower switch SL2 of the second switch unit 112 is the second turn-on section TP22' of the lower switch SL2 of the second switch unit 112; UP11, UP12, UP13, UP14. ) is derived as the tenth and first unit sections UP10 and UP1 disposed at both ends of the . Accordingly, the lower switch SL2 of the second switch unit 112 may be selected as an alternative switch for supplying a negative phase current instead of the faulty switch in at least one of the tenth and first unit sections UP10 and UP1.

Similarly, the upper switch SH3 of the third switch unit 113 corresponding to the positive phase current (ic>0) supplied to phase c is a faulty switch in at least one of the fifth and tenth unit sections UP5 and UP10. Instead, it can be chosen as an alternative switch that supplies a positive phase current.

The lower switch SL3 of the third switch unit 113 corresponding to the negative phase current (ic<0) supplied to phase c is negative instead of the faulty switch in at least one of the twelfth and third unit sections UP12 and UP3. It can be selected as an alternative switch supplying the phase current of

The upper switch SH4 of the fourth switch unit 114 corresponding to the positive phase current (id>0) supplied to phase d is positive instead of the faulty switch in at least one of the seventh and twelfth unit sections UP7 and UP12. It can be selected as an alternative switch supplying the phase current of

The lower switch SL4 of the fourth switch unit 114 corresponding to the negative phase current (id<0) supplied to phase d is negative instead of the faulty switch in at least one of the 14th and 5th unit sections UP14 and UP5. It can be selected as an alternative switch supplying the phase current of

The upper switch SH5 of the fifth switch unit 115 corresponding to the positive phase current (ie>0) supplied to phase e is positive instead of the faulty switch in at least one of the ninth and fourteenth unit sections UP9 and UP14. It can be selected as an alternative switch supplying the phase current of

The lower switch SL5 of the fifth switch unit 115 corresponding to the negative phase current (ie<0) supplied to phase e is negative instead of the faulty switch in at least one of the second and seventh unit sections UP2 and UP7. It can be selected as an alternative switch supplying the phase current of

The upper switch SH6 of the sixth switch unit 116 corresponding to the positive phase current (if>0) supplied to phase f is positive instead of the faulty switch in at least one of the eleventh and second unit sections UP11 and UP2. It can be selected as an alternative switch supplying the phase current of

The lower switch SL6 of the sixth switch unit 116 corresponding to the negative phase current (if<0) supplied to phase f is negative instead of the faulty switch in at least one of the fourth and ninth unit sections UP4 and UP9. It can be selected as an alternative switch supplying the phase current of

The upper switch SH6 of the seventh switch unit 117 corresponding to the positive phase current (ig>0) supplied to phase g is positive instead of the faulty switch in at least one of the thirteenth and fourth unit sections UP13 and UP4. It can be selected as an alternative switch supplying the phase current of

The lower switch SL7 of the seventh switch unit 117 corresponding to the negative phase current (ig<0) supplied to phase g is negative instead of the fault switch in at least one of the sixth and eleventh unit sections UP6 and UP11. It can be selected as an alternative switch supplying the phase current of

Then, the switching control unit 120 when at least one faulty switch is derived among the switches corresponding to any one phase (S40), the switches (SH1, SH2, SH3, SH4, SH5, SH1, SH2, SH3, SH4, SH5, Based on the allowable replacement section (RP11, RP21, RP31, RP32, RP41, RP42, RP51, RP52, RP61, RP62, RP71, RP72) of SH6, SH7) (SL1, SL2, SL3, SL4, SL5, SL6, SL7) Thus, a replacement switch of any one replacement allowable section corresponding to the phase current by each faulty switch and each unit section included in the second turn-on section of each faulty switch is selected. (S80)

As an example, a case in which the upper switch SH1 of the first switch unit 111 supplying a positive phase current (ia>0) to phase a is detected as a faulty switch will be described.

FIG. 16 is a diagram illustrating an example of an equivalent circuit of an inverter corresponding to the second unit section of FIG. 13 when the upper switch of the first switch unit corresponding to the phase a of the inverters of FIG. 12 is faulty.

As shown in FIG. 16 , according to the general driving mode, the rotor position of the second unit section UP2 includes three positive phase currents supplied to a phase, f phase and g phase, b phase, c phase and It corresponds to the three negative phase currents supplied to phase d.

However, when the upper switch SH1 of the first switch unit 111 corresponding to the positive phase current (ia>0) supplied to the phase a is detected as a faulty switch, the supply of the positive phase current to the phase a is stopped. do. At this time, the windings corresponding to the positive phase current have only two f-phase and g-phase excluding the a-phase which is faulty, whereas the windings corresponding to the negative phase current have three phases (b, c, d). Accordingly, an imbalance between phases is caused, thereby generating current and torque pulsation, and when the current and torque pulsation deepens, additional burnout of the switch may occur.

17A and 17B are diagrams illustrating an example of the phase current and counter electromotive force of each phase according to the fault tolerance mode when the upper switch of the first switch unit corresponding to the phase a of the inverter of FIG. 12 is faulty. 18 is a diagram illustrating an example of an equivalent circuit of an inverter corresponding to the second unit section of FIG. 16 .

As shown in FIG. 17A , when the upper switch SH1 of the first switch unit 111 is detected as a faulty switch, the upper switch SH1 of the first switch unit 111 operates during each switching period SP. Since it remains turned off, a positive phase current (ia>0) is not supplied to phase a.

Accordingly, when the switching control unit 120 is detected as a failure and the upper switch SH1 of the first switch unit 111 in the turned-off state corresponds to the rotor position, the upper switch (SH1) of the first switch unit 111 ( The replacement switch corresponding to each unit period UP2 to UP5 included in the second turn-on period TP11' of SH1) is turned on.

17A and 17B , the replacement switch corresponding to the second unit section UP2 among the second turn-on sections TP11 ′ of the upper switch SH1 of the first switch unit 111 is a second unit A sixth switch unit that does not correspond to the rotor position of the section UP2 and provides any one alternative allowable section RP61 that supplies a positive phase current like the upper switch SH1 of the first switch unit 111 (116) is selected by the upper switch (SH6).

Accordingly, as shown in FIG. 18 , the upper switch SH6 of the second unit section UP2 and the sixth switch unit 116 that is the replacement switch of the replacement allowable section RP61 corresponding to the positive phase current is the first It is turned on instead of the upper switch SH1 of the switch unit 111 . Accordingly, the two positive phase currents corresponding to the second unit period UP2 are supplied to the f-phase and the g-phase.

And, as shown in FIGS. 17A and 17B , the replacement switch corresponding to the third unit section UP3 among the second turn-on sections TP11 ′ of the upper switch SH1 of the first switch unit 111 is the third It is selected as the upper switch SH2 of the second switch unit 112 that provides any one replacement allowable period RP21 corresponding to the unit period UP3 and the positive phase current.

The replacement switch corresponding to the fourth unit section UP4 of the second turn-on section TP11 ′ of the upper switch SH1 of the first switch unit 111 corresponds to the fourth unit section UP4 and the positive phase current. It is selected as the upper switch (SH7) of the seventh switch unit 117 providing any one of the allowable replacement section (RP71).

The replacement switch corresponding to the fifth unit period UP5 among the second turn-on period TP11' of the upper switch SH1 of the first switch unit 111 corresponds to the fifth unit period UP5 and the positive phase current. It is selected as the upper switch (SH3) of the third switch unit 113 that provides any one replacement allowable section (RP31).

In this way, instead of the faulty switch maintained in the turn-off state in the fault tolerant mode, by turning on the replacement switch selected to replace the faulty switch, the motor driving can be maintained regardless of the faulty switch. Therefore, the reliability of driving the electric motor can be improved.

Meanwhile, according to another embodiment of the present invention, it is possible to provide a fault tolerance mode even when both the upper and lower switches of the switch unit corresponding to any one phase are detected as failures.

As an example, a case in which the upper switch SH2 and the lower switch SL2 of the second switch unit 112 corresponding to the phase a are detected as malfunctions will be described.

19A and 19B are diagrams illustrating an example of the phase current and counter electromotive force of each phase according to the fault tolerant mode when both the upper and lower switches of the first switch unit corresponding to phase a of the inverter of FIG. 12 fail.

19A, when the upper switch SH1 and the lower switch SL1 of the first switch unit 111 are detected as faulty switches, the upper switch SH1 and the lower end of the first switch unit 111 The switch SL1 is maintained in a turned-off state during each switching period SP. Accordingly, the phase current of phase a is maintained at zero.

As shown in FIGS. 19A and 19B , a replacement allowable section corresponding to each unit section UP2 to UP5 included in the second turn-on section TP11 ′ of the upper switch SH1 of the first switch unit 111 . Alternative switches providing (RP61, RP21, RP71, RP31) are the sixth switch unit 116, the second switch unit 112, the seventh switch unit 117 and the third switch unit 113, respectively, the upper switch (SH6, SH2, SH7, SH3).

Similarly, the replacement allowable section (RP62, RP22, RP72, RP32) corresponding to each unit section (UP9 ~ UP12) included in the second turn-on section (TP21') of the lower end switch (SL1) of the first switch unit 111 (RP62, RP22, RP72, RP32) Alternative switches that provide the sixth switch unit 116, the second switch unit 112, the seventh switch unit 117 and the third switch unit 113, respectively, the lower switches (SL6, SL2, SL7, SL3) is selected as

As described above, even if the upper switch and the lower switch included in the switch unit corresponding to any one phase in the 7-phase similarly to the 5-phase fail, the failure tolerance mode can be provided.

For those of ordinary skill in the art to which the present invention pertains, various substitutions, modifications and changes are possible within the scope of the present invention without departing from the technical spirit of the present invention. is not limited by

100: polyphase motor drive
110: inverter 120: switching control unit
130: fault detection unit 200: polyphase motor
SP: switching period UP: unit section
TP: first turn-on period TP': second turn-on period
RP: Alternative Allowable Section

Claims (11)

an inverter supplying driving power to the polyphase motor;
a switching controller for controlling a turn-on-turn-off operation of each switch included in the inverter; and
and a failure detection unit for detecting whether a switch corresponding to each phase current fails on the basis of the phase current supplied to each phase of the electric motor;
The switching control unit
A turn-on signal is supplied to each switch of the inverter during a predetermined first turn-on period corresponding to each switch of the inverter during each switching cycle according to the normal driving mode,
When the failure detection unit detects at least one of the switches corresponding to any one phase of the motor as a failure, it switches to a failure tolerance mode,
According to the fault tolerance mode, the turn-on signal is supplied to each switch of the inverter during a second turn-on period corresponding to each switch of the inverter during each switching period and smaller than the first turn-on period, and at least detected as the failure A polyphase motor drive that maintains the supply of a turn-off signal to each of one faulty switch.
The method of claim 1,
The electric motor includes 2n rotor positions corresponding to n phases,
The switching control unit
In accordance with the normal driving mode, the inverter is driven in a (n-1)-phase energization method,
A multi-phase motor driving device for driving the inverter in a (n-3)-phase energization method according to the fault tolerance mode.
3. The method of claim 2,
Each switching period consists of 2n unit sections corresponding to the 2n different rotor positions,
The inverter includes n switch units,
Each of the n switch units includes an upper switch corresponding to a positive phase current and a lower switch corresponding to a negative phase current,
The switching control unit
Based on the difference between the first turn-on period and the second turn-on period of each switch included in the inverter, a replacement allowable period of each switch is derived,
Each unit section included in the second turn-on section of each faulty switch among the replacement permissible sections of the switches included in the inverter and the replacement permissible section of any one replacement switch corresponding to the sign of the phase current by each faulty switch choose,
A polyphase motor driving apparatus for supplying the turn-on signal to the selected replacement switch instead of the respective faulty switch during each unit section included in the second turn-on section of each faulty switch according to the fault tolerance mode.
4. The method of claim 3,
The allowable replacement section of each switch is derived from two unit sections disposed at both ends of the second turn-on section of each switch.
3. The method of claim 2,
wherein n is 5 or 7;
A method for controlling the inverter by a polyphase motor driving device including an inverter for driving a polyphase motor and supplying driving power to the motor,
driving the inverter in a (n-1)-phase energized manner according to a normal driving mode;
detecting a failure of a switch corresponding to each phase current based on the phase current supplied to each phase of the electric motor;
when at least one of the switches corresponding to any one phase of the electric motor is detected as a failure, turning off the at least one failure switch detected as a failure, and switching to a failure tolerance mode; and
and driving the inverter in a (n-3)-phase energized manner according to the fault tolerance mode,
In the step of driving the inverter according to the normal driving mode, each switch of the inverter is turned on during the first turn-on period corresponding to the (n-1) phase conduction method during each switching period,
In the step of driving the inverter according to the fault tolerance mode, each switch of the inverter is turned on during a second turn-on period that corresponds to the (n-3)-phase energization method during each switching period and is shorter than the first turn-on period Inverter control method of an electric motor driving device.
7. The method of claim 6,
The electric motor includes 2n rotor positions corresponding to n phases,
Each switching period consists of 2n unit sections corresponding to the 2n different rotor positions,
The first turn-on section corresponding to the (n-1) phase energization method consists of (n-1) unit sections,
The second turn-on section corresponding to the (n-3) phase energization method includes (n-3) unit sections.
8. The method of claim 7,
Before the step of driving the inverter according to the fault tolerance mode,
deriving an allowable replacement section of each switch based on a difference between the first turn-on section and the second turn-on section of each switch included in the inverter; and
When the at least one faulty switch is detected, any one corresponding to each unit section included in the second turn-on section of each faulty switch among the replacement allowable sections of the switches included in the inverter and the phase current by each faulty switch Inverter control method of a polyphase motor driving device further comprising the step of selecting a replacement allowable section of the replacement switch.
9. The method of claim 8,
In the step of deriving the allowable replacement section of each switch, the allowable replacement section of each switch is derived from two unit sections disposed at both ends of the second turn-on section of each switch. Inverter control method of a polyphase motor driving device .
9. The method of claim 8,
In the step of driving the inverter according to the fault tolerance mode,
Inverter control method of a polyphase motor driving device for turning on the selected replacement switch instead of each faulty switch during each unit section included in the second turn-on section of each faulty switch according to the fault tolerance mode.
8. The method of claim 7,
Wherein n is 5 or 7. Inverter control method of a polyphase motor driving device.

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