JP2014003823A - Motor driving unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor driving unit capable of suppressing a current ripple generated in an inverter circuit when a phase-shift phase of a notch wave is switched.SOLUTION: Immediately after timing at which the phase-shift phase of the notch wave is switched, prohibited is outputting of the voltage to the pair-line where a voltage has not outputted immediately before the phase-shift phase switching timing among two or more output pair-lines. For example, during one PWM period immediately after the switching of the phase-shift phase is performed, the inverter circuit is switched so that the voltage may not be outputted to any pair-lines.

Description

  The present invention relates to a motor drive device that drives a motor using an inverter circuit.

  Conventionally, for example, a motor that drives a three-phase motor by converting a direct-current voltage into an alternating current by switching of a switching element of an inverter circuit and outputting the voltage to a three-phase motor coil via three output lines There is a drive. In such a motor driving device, one of the three phases is changed as a switching stationary phase, and the stationary phase is sequentially changed, and the notch wave of one phase of the two phases not fixed is changed to the notch wave of the other phase. It is known that the phase is shifted with respect to the phase and the phase shift phase is also changed sequentially with the change of the stationary phase (for example, see Patent Document 1).

JP 2006-197760 A

  However, in the prior art motor driving device, when the phase shift phase of the notch wave is switched, the line between which the voltage is output is switched among the lines of the three output lines. By switching between the lines that output voltage in this way, the output voltage waveform becomes irregular when the phase shift phase is switched, and this may cause a problem that a relatively large current ripple occurs in the inverter circuit. is there. The generation of a large current ripple has a problem in that, for example, the smoothing capacitor provided in the inverter circuit is damaged and causes a reduction in life.

  The present invention has been made in view of the above points, and an object thereof is to provide a motor drive device capable of suppressing current ripple generated in an inverter circuit when switching the phase shift phase of a notch wave. To do.

In order to achieve the above object, in the present invention,
The control means (100) has phase shift means (130) for shifting the phase of the notch wave corresponding to at least one of the plurality of phases with respect to the reference carrier wave,
The phase shift means is a motor drive device that sequentially switches the phase for shifting the phase of the notch wave,
The control means immediately after the timing at which the phase to which the notch wave is shifted is switched by the phase shift means, immediately before the timing at which the phase to be shifted among the plurality of output lines (45) is switched. It is characterized by prohibiting the output of a voltage between lines that did not output.

  According to this, the control means switches the phase shift phase between the output lines that did not output the voltage just before the timing at which the phase shift phase of the notch wave is switched by the phase shift means. The switching operation of the switching element is performed so as not to output a new voltage immediately after the timing. Therefore, when the phase shift phase of the notch wave is switched, a new line voltage is not generated, and the output voltage waveform is unlikely to be irregular. In this manner, current ripple generated in the inverter circuit can be suppressed when switching the phase shift phase of the notch wave.

  In addition, the code | symbol in the parenthesis attached | subjected to each said means is an example which shows a corresponding relationship with the specific means as described in embodiment mentioned later.

It is the circuit diagram which showed the motor drive device in 1st Embodiment to which this invention was applied with the one part block. It is a flowchart which shows schematic control operation | movement of a control apparatus. It is a graph which shows a modulation wave, a reference carrier wave, and a switching signal generated from them. It is a graph which shows the state which carried out the phase shift of a part of switching signal shown in FIG. It is a graph which shows the difference of the switching signal output by the presence or absence of a phase shift. It is a graph which shows the relationship between switching of a phase shift phase and a line voltage. It is a graph which shows the change of the current ripple by switching of a phase shift phase. It is a graph which shows the relationship between the switching of the phase shift phase in a comparative example, and a line voltage. It is a graph which shows the change of the current ripple by switching of the phase shift phase in a comparative example. It is a graph which shows the relationship between the switching of the phase shift phase in 2nd Embodiment, and a line voltage. It is a graph which shows the relationship between the switching of the phase shift phase in 3rd Embodiment, and a line voltage.

  A plurality of modes for carrying out the present invention will be described below with reference to the drawings. In each embodiment, parts corresponding to the matters described in the preceding embodiment may be denoted by the same reference numerals, and redundant description may be omitted. In the case where only a part of the configuration is described in each embodiment, the other parts of the configuration are the same as those described previously. In addition to the combination of parts specifically described in each embodiment, the embodiments may be partially combined as long as the combination is not particularly troublesome.

(First embodiment)
A first embodiment to which the present invention is applied will be described with reference to FIGS.

  As shown in FIG. 1, the motor drive device of this embodiment is for driving a synchronous motor 12 of an electric compressor 10. The electric compressor 10 is a compressor disposed in a heat pump cycle of a vehicle air conditioner using, for example, carbon dioxide as a refrigerant, and drives a compression mechanism 11 as a load by a built-in synchronous motor 12. The electric compressor 10 is an electric compressor that compresses and discharges a gas-phase refrigerant (for example, compressed to a critical pressure or more in the case of carbon dioxide refrigerant) in the compression mechanism 11. The synchronous motor 12 of the present embodiment is, for example, a synchronous motor having a four-pole three-phase coil that rotationally drives a rotor in which magnets are embedded.

  The DC power supply 20 shown in FIG. 1 is a high voltage battery capable of outputting a voltage of 288V, for example. A high voltage relay system 50 is disposed on a pair of buses 30 extending from the DC power supply 20 to the inverter circuit 40. The high voltage relay system 50 includes a plurality of relays and resistors. When applying a high voltage, the high voltage relay system 50 starts the voltage application in a path having a resistor and then switches to a path having no resistor so that no inrush current flows in the bus 30. It has a function to do.

  Moreover, the high voltage relay system 50 interrupts | blocks an electric power feeding path, when an abnormal state is detected by the electric compressor 10 grade | etc.,.

  As shown in FIG. 1, capacitors 60 and 70 as smoothing means are interposed between a pair of bus bars 30. Capacitor 60 is provided to smooth a voltage that fluctuates due to the influence of other device 9 connected in parallel to inverter circuit 40 with respect to bus 30. Here, examples of the other device 9 include a vehicle driving motor drive device, a charging device, a step-down DC / DC conversion device, and the like.

  The capacitor 70 is provided in order to absorb surges and ripples that are generated when the switching elements of the inverter circuit 40 are switched.

  A coil 80 is disposed between the connection point of the capacitor 60 and the connection point of the capacitor 70 on one bus 30. The coil 80 is provided to suppress interference between the two capacitors 60 and 70 provided in parallel between the bus bars 30. The coil 80 is provided for the purpose of changing the resonance frequency generated by the relationship between the capacitor 60 and the capacitor 70.

  The inverter circuit 40 is composed of arms for three phases of U phase, V phase, and W phase corresponding to the stator coil of the synchronous motor 12, and converts the DC voltage input via the bus 30 into AC by PWM modulation. Output.

  The U-phase arm is configured by connecting in series an upper arm in the figure in which the switching element and the reflux diode are connected in antiparallel, and a lower arm in the figure in which the switching element and the diode are antiparallel connected, An output line 45 extending from a connection portion between the upper arm and the lower arm is connected to the motor coil. The V-phase arm and the W-phase arm are similarly configured by a switching element and a diode, and an output line 45 extending from a connection portion between the upper arm and the lower arm is connected to the motor coil.

As the switching element, for example, an element such as an IGBT (Insulated Gate Bipolar Transistor) can be used. In addition, an arm composed of a switching element and a diode, for example, RCIGBT (Reverse Conducting) which is a power semiconductor in which an IGBT and a reverse conducting diode are integrated on one chip
A switching element such as Insulated Gate Bipolar Transistor may also be used.

  The control device 100 as a control means is a drive circuit unit that controls the switching operation of each switching element of the inverter circuit 40 and controls the driving of the synchronous motor 12. The control device 100 inputs the motor coil current value information detected by the current detector 90 provided on the bus 30, generates a notch wave as a switching signal based on this, and outputs it to the inverter circuit 40. .

  As shown in FIG. 2, the control device 100 first generates a notch wave that is a switching wave by comparing a modulated wave that is a voltage command applied to the motor coil and a reference carrier wave (step 110).

  As shown in FIG. 3, the switching of each phase for one PWM period (here, one period of the reference carrier) from the comparison result between the triangular wave that is the reference carrier and the modulation rates Vu, Vv, and Vw of each phase. Waves PWu, PWv, and PWw are generated. 1 of each phase switching wave is a signal for turning on the upper arm and turning off the lower arm, and 0 of each phase switching wave is a signal for turning off the upper arm and turning on the lower arm.

  If the switching wave of each phase is generated in step 110, then the phase operation signal of each phase corresponding to the combination of the modulation factors of each phase stored in advance in the storage means is acquired (step 120). Here, the phase operation signal is, for example, a phase shift signal that shifts the switching wave by 180 ° (for a half period of the reference carrier wave).

  When the phase operation signal is acquired in step 120, the phase of the switching wave is shifted based on this signal, and the switching wave for switching the switching element of each phase arm is set (step 130). As shown in FIG. 4, when the V-phase operation signal is in an ON state in which phase shifting is performed, the phase of the V-phase switching wave PWv is shifted.

  As illustrated in FIG. 5, after the phase operation signal is switched from OFF to ON, when the phase operation is performed when the phase operation is not performed, the waveform of the output switching wave is a half cycle. Output after a minute delay.

  As shown in FIG. 3 and FIG. 4, in this example, two-phase modulation is performed using one of the three phases (W-phase in the illustrated example) as a stationary phase, and two phases other than the stationary phase. Of these, one phase is shifted. Then, the phase shift phase is sequentially switched based on the acquired phase operation signal.

  Here, step 130 corresponds to phase shift means for shifting the phase of the notch wave corresponding to at least one of the plurality of phases with respect to the reference carrier wave.

  If the switching wave of each phase is set in step 130, it is next determined whether it is a phase operation timing (step 140). Specifically, it is determined whether the phase to be phase-shifted is switched from the phase operation signal acquired in step 120 in the current flow and the phase operation signal acquired in step 120 in the previous flow. .

  When it is determined in step 140 that the phase shift phase is not switched (in the case of NO), the switching wave set in step 130 is adopted as the switching wave for 1 PWM period (step 150), and the adopted switching wave is used. The operation is controlled by outputting to each phase arm (step 170). When step 170 is executed, the process returns to step 110 for the control of the next 1PWM period.

  When it is determined in step 140 that the phase shift phase is switched (in the case of YES), regardless of the switching wave set in step 130, the switching wave of (000) or (111) is changed to the switching wave of 1 PWM period. (Step 160). Here, the numerical strings in parentheses indicate the switching states of the U-phase, V-phase, and W-phase arms in order from the front. When executing step 160, (000) is set when the switching state of the stationary phase arm is 0, and (111) is set when the switching state of the stationary phase arm is 1.

  When the switching wave of (000) or (111) is set in step 160, the switching wave set in step 160 is output to each phase arm to control the operation of the switching element (step 170), and the process returns to step 110.

  According to the above-described configuration and operation, the control device 100 immediately after the timing at which the phase shift phase of the notch wave that is a switching wave is switched, of the phase shift phase switching timing among the plurality of output lines 45. Prohibit voltage output between lines that did not output voltage immediately before.

  That is, the control device 100 immediately after the timing at which the phase shift phase is switched to the line between the output lines 45 that has not output a voltage immediately before the timing at which the phase shift phase of the switching wave is switched. Then, the switching operation of the switching element is performed so as not to output a new voltage.

  Therefore, when switching the phase shift phase of the switching wave, a new line voltage is not generated, and the output voltage waveform is unlikely to be irregular. Thus, the current ripple generated in the inverter circuit 40 can be suppressed when switching the phase shift phase of the switching wave. By suppressing the current ripple, damage to the capacitors 60 and 70, the coil 80, and the like can be reduced.

  Further, the control device 100 prohibits voltage output between all the output lines 45 in accordance with the timing at which the phase shift phase of the switching wave is switched, so that the control device 100 immediately after the phase shift phase switching timing. The output of the voltage between the output lines 45 that did not output the voltage immediately before the phase shift phase switching timing is prohibited.

  According to this, the control device 100 performs the switching operation of the switching element so as to prohibit the output of the voltage to the motor coil in accordance with the timing at which the switching of the phase shift phase of the switching wave is performed.

  Therefore, it is possible to suppress the output voltage waveform from becoming irregular when the phase shift phase of the switching wave is switched by a relatively simple control of prohibiting voltage output in accordance with the phase shift phase switching timing. Thus, the current ripple generated in the inverter circuit 40 can be easily suppressed when switching the phase shift phase of the switching wave.

  Moreover, the control apparatus 100 repeats the control operation | movement of the flow shown in FIG. 2 with a predetermined period. That is, the control device 100 regenerates the switching wave at a predetermined time interval, updates the time interval (in this example, 1 PWM period) for outputting the voltage based on the regenerated switching wave, and sets the time interval. The phase shift phase of the switching wave is switched in accordance with the timing at which the signal is updated. Then, in the time interval immediately after the switching of the phase shift phase of the switching wave, the control device 100 performs a predetermined time (all in one PWM period in this example) from the start time of this time interval for the voltage. Prohibit output.

  According to this, the control device 100 regenerates the switching wave and updates the time interval for outputting the voltage, and switches the phase shift phase of the switching wave in accordance with the timing for updating this time interval. It is like that. Then, the control device 100 performs the switching operation of the switching element so as to prohibit the output of the voltage for a predetermined time after the start in the time interval immediately after the switching of the phase shift phase of the switching wave. Therefore, the output voltage waveform is unlikely to become irregular when the time interval for switching the phase shift phase of the switching wave is updated. Thus, when switching the phase shift phase of the switching wave, the current ripple generated in the inverter circuit can be reliably suppressed.

  In addition, in the time interval immediately after the switching of the phase shift phase of the switching wave, the control device 100 prohibits voltage output from the start point to the end point of the time interval. That is, voltage output is not performed in the time interval immediately after switching of the phase shift phase of the switching wave. Therefore, the voltage output inhibition control is very easy.

  The results confirmed by the present inventor for the operation and effects of the above-described embodiment will be described with reference to the drawings.

  In the motor drive device of the present embodiment, the control device 100 executes the flow shown in FIG. 2 every 50 μs, for example, and performs switching output for each PWM period. The interval between the broken lines extending vertically in FIG. 6 is the above-described time interval (1 PWM period). While the 1PWM period proceeds, the control device 100 executes the flow shown in FIG. 2 and executes step 170 at the timing of the broken line to perform switching output for the next 1PWM period after the broken line.

  For example, as shown in the upper part of FIG. 6, the phase shift signal of each phase is turned on and off. In FIG. 6, before the phase shift phase is switched, the V phase is the stationary phase, and the U phase is the phase shift phase among the two phases other than the stationary phase. After the timing when the phase shift phase is switched, the U phase is the stationary phase, and the V phase is the phase shift phase among the two phases other than the stationary phase. That is, the phase shift phase is switched from the U phase to the V phase at the phase shift phase switching timing indicated by the arrows in FIG.

  In FIG. 6, the phase shift signal is switched in advance of the phase shift phase switching timing because acquisition of the phase shift signal for determining the switching output in one PWM period immediately after the phase shift phase switching (step 120 in FIG. 2). This is because it corresponds to (execution of execution).

  As is apparent from the voltage change between the output lines 45 shown in the lower part of FIG. 6, no voltage is output between any lines in the 1 PWM period immediately after the phase shift phase is switched. In the lower part of FIG. 6, the waveform indicated by the solid line is the line voltage Vuv between the U-phase arm output line and the V-phase arm output line. A waveform indicated by a fine broken line is a line voltage Vvw between the V-phase arm output line and the W-phase arm output line, and a waveform indicated by a rough broken line is a line between the W-phase arm output line and the U-phase arm output line. Inter-voltage Vwu.

  In this way, voltage output in the immediately following 1 PWM period is stopped in accordance with the timing of phase shift phase switching. Thereby, as shown in FIG. 7, when the phase shift phase switching operation is performed, the current ripple is suppressed. In FIG. 7, in order to make the change in the current value easy to understand, a current value waveform longer than the time shown in FIG. 6 is shown.

  When the normal switching operation is performed immediately after the switching of the phase shift phase, that is, when the switching operation is performed in a flow that does not include step 140 and step 160 of the flowchart shown in FIG. 2, for example, as shown in FIG. Waveform line voltage is output. Immediately after the phase shift phase switching, the line voltage Vwu between the W-phase arm output line and the U-phase arm output line that was not output immediately before is output.

  As a result, as shown in FIG. 9, the current ripple after the phase shift phase switching operation is increased. As can be seen by comparing FIG. 7 and FIG. 9, by applying the present invention, a current ripple reduction effect of about 20% in effective value is obtained.

  Further, the control device 100 according to the present embodiment, in the time interval immediately after the switching of the phase shift phase of the switching wave, in addition to the predetermined time after the start of this time interval, the predetermined time before the end until the end time, It can be said that voltage output is prohibited.

  According to this, the control device 100 performs the switching operation of the switching element so as to prohibit the output of the voltage at the predetermined time after the start and the predetermined time before the end in the time interval immediately after the switching of the phase shift phase of the switching wave. I do. Therefore, in the time interval in which the phase shift phase of the switching wave is switched, it is easy to ensure the symmetry of the voltage output on the time passage axis. Thereby, when switching the phase shift phase of a switching wave, the current ripple which generate | occur | produces in an inverter circuit can be suppressed more reliably.

(Second Embodiment)
Next, a second embodiment will be described based on FIG.

  The second embodiment differs from the first embodiment in that voltage output is partially performed in the time interval immediately after the phase shift phase switching. In addition, the component which attached | subjected the same code | symbol as drawing based on 1st Embodiment, and the other structure which is not demonstrated in 2nd Embodiment are the same as that of 1st Embodiment, and there exists the same effect. It is.

  In the motor drive device of the present embodiment, when the control device determines that the phase shift phase is switched in step 140 shown in FIG. 2, unlike step 160 in FIG. For the predetermined time and the predetermined time before the end, the switching wave of (000) or (111) is set as in the first embodiment. Then, a preset switching wave is set for an intermediate time period excluding a predetermined time at the start of one PWM period and a predetermined time before the end. As a result, for example, as shown in FIG. 10, the line voltage is output in the intermediate time period within one PWM period immediately after the phase shift phase switching.

  As described above, the control device according to the present embodiment outputs the voltage during the time period immediately after the switching of the phase shift phase of the switching wave, except for the predetermined time after the start and the predetermined time before the end. The inverter circuit 40 is controlled.

  According to this, voltage can be output in a time zone other than the predetermined time after the start and the predetermined time before the end in the time interval immediately after the switching of the phase shift phase of the switching wave. Therefore, in the time interval immediately after the switching of the phase shift phase of the switching wave, by ensuring the symmetry of the voltage output on the time lapse axis, the current ripple is reliably suppressed, and the current flows to the motor coil. Reduction of current can be suppressed.

  As described above, the switching output in the intermediate time zone is performed for the purpose of suppressing the reduction of the current flowing through the motor coil while reliably suppressing the generation of current ripple. Therefore, the switching wave in the intermediate time zone preferably forms a voltage vector that suppresses a decrease in the absolute value of the current vector while maintaining the rotation speed of the current vector, for example, on the rotation coordinates.

  Also in this embodiment, it is easy to ensure the symmetry of the voltage output on the time lapse axis in the time interval in which the phase shift phase of the switching wave is switched. Thereby, when switching the phase shift phase of a switching wave, the current ripple which generate | occur | produces in an inverter circuit can be suppressed more reliably.

(Third embodiment)
Next, a third embodiment will be described with reference to FIG.

  The third embodiment is different from the first embodiment in that voltage output is performed immediately after the start of the time interval in the time interval immediately after the phase shift phase switching. In addition, the component which attached | subjected the same code | symbol as drawing concerning 1st, 2nd embodiment, and the other structure which is not demonstrated in 3rd Embodiment are the same as that of 1st, 2nd embodiment, and the same The effect of this is achieved.

  In the motor drive device of the present embodiment, when the control device determines that the phase shift phase is switched in step 140 shown in FIG. 2, unlike in step 160 of FIG. Set a special switching wave.

  As shown in FIG. 11, this special switching wave is a switching wave in which the line voltage continues before and after the phase shift phase is switched. Further, the switching wave is such that the line voltage continues between the 1 PWM period immediately after the phase shift phase switching and the 1 PWM period of the normal control in which the phase shift phase switching immediately after that is reflected.

  As described above, the control device according to the present embodiment immediately before the phase shift phase switching timing among the lines of the plurality of output lines 45 immediately after the timing at which the phase shift phase of the notch wave that is a switching wave is switched. The voltage output to the line that did not output the voltage is prohibited.

  In other words, the control device according to the present embodiment has a timing at which the phase shift phase is switched between the lines of the output lines 45 that have not output a voltage immediately before the timing at which the phase shift phase of the switching wave is switched. Immediately after, the switching operation of the switching element is performed so as not to output a new voltage.

  Therefore, when switching the phase shift phase of the switching wave, a new line voltage is not generated, and the output voltage waveform is unlikely to be irregular. Thus, the current ripple generated in the inverter circuit 40 can be suppressed when switching the phase shift phase of the switching wave.

  Further, the control device of the present embodiment performs the switching operation of the switching element so that the voltage waveform between the lines before and after the timing at which the phase shift phase of the switching wave is switched is continuous. Therefore, the current ripple generated in the inverter circuit 40 can be reliably suppressed when switching the phase shift phase of the switching wave.

(Other embodiments)
The preferred embodiments of the present invention have been described above, but the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

  In the first embodiment, in the time interval immediately after the phase shift phase of the notch wave is switched, voltage output is prohibited from the start point to the end point. In the second embodiment, In the time interval immediately after the phase shift phase of the notch wave is switched, the voltage output is prohibited at a predetermined time after the start and at a predetermined time before the end, and the voltage is applied at a time excluding the predetermined time after the start and the predetermined time before the end. Although it output, it is not limited to these. For example, in the time interval immediately after switching of the phase shift phase of the notch wave, voltage output is prohibited only for a predetermined time after the start of the time interval, and the voltage is not applied in the remaining time zone. It may be output.

  In each of the above embodiments, a notch wave is regenerated at a predetermined time interval, and a time interval (1 PWM period in each example above) for outputting a voltage is updated based on the regenerated notch wave. The time interval corresponds to one period of the reference carrier wave, but is not limited thereto. For example, two periods of the reference carrier may be used as the time interval.

  Moreover, although the reference carrier wave is a triangular wave, it is not limited to this. For example, the reference carrier wave may be a sawtooth wave.

  In each of the above embodiments, the time interval is updated at the timing at which the value of the triangular wave that is the reference carrier wave is maximized. However, the present invention is not limited to this. For example, the time interval may be updated at a timing at which the triangular wave value is minimized. Further, the time interval may be updated at a timing other than the timing at which the value of the triangular wave is maximized or minimized.

  In each of the above embodiments, the notch wave is regenerated at a predetermined time interval, and the phase shift phase of the notch wave is switched when the time interval in which the voltage is output based on the regenerated notch wave is updated. Although it is what is performed, it is not limited to this. For example, the phase shift phase may be switched in the middle of the time interval.

  In each of the above embodiments, when the phase of the notch wave is shifted, the phase is shifted by a half period of the reference carrier wave, but the present invention is not limited to this.

  In each of the above embodiments, one of the three phases is used as a switching stationary phase, the stationary phase is sequentially changed, and the phase of the notch wave of one of the two phases that are not fixed is shifted to change the stationary phase. Accordingly, the phase shift phase is also changed sequentially, but is not limited to this. For example, the switching stationary phase may not be provided.

  Further, the motor to be driven is not limited to a three-phase motor. For example, a motor having four or more phases may be used as long as the control device shifts the phase of at least one notch wave.

  Moreover, in each said embodiment, although the motor drive device drives the motor which makes the load the compression mechanism of the compressor arrange | positioned during the heat pump cycle of a vehicle air conditioner, it is limited to this. It is not a thing.

12 Synchronous motor 40 Inverter circuit 45 Output line 100 Control device (control means)

Claims (6)

An inverter circuit (40) having a switching element provided corresponding to the plurality of phases of a motor having a motor coil of a plurality of phases;
The switching element is switched by a notch wave generated based on a comparison result between a modulated wave that is an applied voltage command to each phase of the plurality of phases and a reference carrier wave, and a DC voltage is converted into an AC voltage by PWM modulation, Control means (100) for controlling the inverter circuit to output to a multi-phase motor coil;
A plurality of output lines (45) for outputting a voltage from the inverter circuit to the motor coils of the plurality of phases,
The control means includes phase shift means (130) for shifting the phase of the notch wave corresponding to at least one of the plurality of phases with respect to the reference carrier wave,
The phase shift means is a motor drive device that sequentially switches phases for shifting the phase of the notch wave,
The control means does not output a voltage immediately before the timing among the plurality of output lines immediately after the timing at which the phase to be shifted of the notch wave is switched by the phase shifting means. And a motor driving device that prohibits voltage output between the lines.   The control unit prohibits the output of the voltage between all the lines in accordance with the timing at which the phase to be shifted of the notch wave is switched by the phase shift unit, and immediately after the timing. 2. The motor driving apparatus according to claim 1, wherein output of a voltage between the lines that has not output the voltage immediately before the timing is prohibited. The control means includes
Regenerating the notch wave at a predetermined time interval and updating the time interval for outputting the voltage based on the regenerated notch wave;
In accordance with the timing of updating the time interval, the phase shift means switches the phase to be shifted of the notch wave,
The control means includes
In the time interval immediately after the phase of the notch wave is switched by the phase shift means, the output of the voltage is prohibited for a predetermined time after the start of the time interval. The motor driving device according to claim 2. The control means includes
In the time interval immediately after the phase to be shifted of the notch wave is switched by the phase shift means, in addition to the predetermined time after the start of the time interval, the predetermined time before the end until the end time is also The motor drive device according to claim 3, wherein output of voltage is prohibited. The control means includes
In the time interval immediately after the shift phase of the notch wave is switched by the phase shift means, the output of the voltage is prohibited from the start time to the end time. The motor drive device according to claim 4. The control means includes
In the time interval immediately after the shift phase of the notch wave is switched by the phase shift means, the voltage is output at a time excluding the predetermined time after the start and the predetermined time before the end. The motor driving apparatus according to claim 4, wherein the motor driving apparatus controls an inverter circuit.

Images