JP4989591B2 - Permanent magnet synchronous motor driving device, air conditioner, ventilation fan driving device, washing machine, automobile and vehicle - Google Patents

Description

  The present invention drives a permanent magnet synchronous motor that secures the safety of a driving device by suppressing a regenerative voltage that is generated when a permanent magnet synchronous motor with high energy-saving and large induced voltage constant is forcibly rotated. The present invention relates to a device, an air conditioner, a driving device for a ventilation fan, a washing machine, an automobile, and a vehicle.

Conventionally, as the induced voltage constant of a permanent magnet synchronous motor increases, the loss of a motor drive device represented by an inverter can be reduced. However, the permanent magnet synchronous motor works as a generator and generates a voltage (regenerative voltage) when it is forced to rotate due to external wind or other disturbance factors.
For this reason, when a permanent magnet synchronous motor with a large induced voltage constant is used, a large regenerative voltage is generated, and the elements constituting the motor drive device may break down with pressure, leading to smoke or ignition.
Therefore, a conventional brushless motor protection device has a technique for protecting an element against a regenerative voltage by separating a motor and an inverter by a switch such as a relay (see, for example, Patent Document 1).

JP 63-206189 A (first page, FIG. 1)

However, the conventional protection device for a brushless motor described in Patent Document 1 has a problem of increased costs due to an increase in the number of parts and the area of an electronic board due to the addition of a switch such as a relay. There was also a problem that the design had to be taken into account.
The present invention has been made to solve such a problem, and a permanent magnet synchronous motor capable of reducing the cost by suppressing the regenerative voltage generated when the permanent magnet synchronous motor is forcibly rotated without increasing the number of parts. An object of the present invention is to obtain a driving device, an air conditioner, a ventilation fan driving device, a washing machine, an automobile and a vehicle.

A permanent magnet synchronous motor driving apparatus according to the present invention includes a DC voltage of a DC power supply as an input, an inverter that outputs a voltage to the permanent magnet synchronous motor, and a DC voltage detection that detects a DC regenerative voltage appearing on the input side of the inverter. And inverter control means for controlling the voltage output from the inverter, and the inverter control means is configured to provide a gap between the inverter and the permanent magnet synchronous motor based on the increased regenerative voltage detected by the DC voltage detection means during regenerative operation. Short-circuit means for controlling the inverter so as to short-circuit, open-circuit means for controlling the inverter so as to open the line between the inverter and the permanent magnet synchronous motor based on the decreasing regenerative voltage detected by the DC voltage detection means, and DC voltage Based on the increasing regenerative voltage detected by the detection means, the inverter and the permanent magnet synchronous motor are alternately opened and shorted between the lines. An intermittent short-circuit means for controlling the inverter to perform the operation, and when the increasing regenerative voltage detected by the DC voltage detection means exceeds the first threshold, the intermittent short-circuit means is operated, and then the short-circuit means is operated. The release means is operated when the decreasing regenerative voltage detected by the DC voltage detection means falls below the second threshold value .

In the permanent magnet synchronous motor driving apparatus according to the present invention, a DC voltage of a DC power supply is input, an inverter that outputs a voltage to the permanent magnet synchronous motor, and a DC voltage that detects a DC regenerative voltage appearing on the input side of the inverter Detecting means and inverter control means for controlling the voltage output from the inverter, and the inverter control means is arranged between the line between the inverter and the permanent magnet synchronous motor based on the increasing regenerative voltage detected by the DC voltage detecting means during the regenerative operation. A short-circuit means for controlling the inverter so as to short-circuit, an open-circuit means for controlling the inverter so as to open a line between the inverter and the permanent magnet synchronous motor based on a decreasing regenerative voltage detected by the DC voltage detection means, Based on the increasing regenerative voltage detected by the voltage detector, the line between the inverter and the permanent magnet synchronous motor is opened and closed. Intermittent short-circuit means for controlling the inverter so as to alternately perform the operation, and when the increasing regenerative voltage detected by the DC voltage detection means exceeds the first threshold, the intermittent short-circuit means is operated, and then the short-circuit means When the decreasing regenerative voltage detected by the DC voltage detecting means falls below the second threshold value, the opening means is operated , and the permanent magnet synchronous motor is forcibly rotated to generate the regenerative voltage. In addition, the regenerative voltage generated in the permanent magnet synchronous motor is consumed in the permanent magnet synchronous motor by short-circuiting the line between the inverter and the permanent magnet synchronous motor, and repeating the short circuit and the open circuit, thereby suppressing the DC voltage rise. The regenerative voltage can be suppressed below the withstand voltage of the inverter, and the breakdown voltage of the switching elements that constitute the inverter can be prevented at low cost without increasing the number of parts. Since it is possible to use a permanent magnet synchronous motor having a large induced voltage constant, it is possible to reduce energy loss by reducing the loss of the drive device of the permanent magnet synchronous motor and to reduce global warming. .

Embodiment 1
1 is a block diagram of a driving apparatus for a permanent magnet synchronous motor according to Embodiment 1 of the present invention, FIG. 2 is a circuit diagram of a three-phase bridge of an inverter of the driving apparatus for the permanent magnet synchronous motor, and FIG. 4 is a circuit diagram of a short circuit operation state of the inverter of the synchronous motor driving device, FIG. 4 is a circuit diagram of an open state of the inverter of the permanent magnet synchronous motor driving device, and FIG. 5 is a circuit diagram of the inverter of the permanent magnet synchronous motor driving device. FIG. 6 is a flowchart of a short circuit and an open operation (when DC voltage detecting means is used), FIG. 6 is a DC voltage waveform diagram due to a short circuit and an open operation of the inverter of the permanent magnet synchronous motor driving device, and FIG. FIG. 8 is an explanatory diagram showing switching waveforms at the time of opening, intermittent short-circuiting, and opening operation of the inverter of the driving device, and FIG. Block diagram showing the ratio control operating time, FIG. 9 is a block diagram showing the internal configuration of the controller of the permanent magnet synchronous motor driving device.

In FIG. 1, 10 is a DC power source, 20 is a motor drive device connected to the DC power source 10 on the input side, and 30 is a three-phase permanent magnet synchronous motor connected to the output side of the motor drive device 20.
The motor drive device 20 includes an inverter 40, an inverter control means 50 that controls the drive of the inverter 40, a short-circuit means 60 that controls the inverter 40 so as to short-circuit between the lines of the permanent magnet synchronous motor 30, and the permanent magnet synchronous motor 30. An open means 70 for controlling the inverter 40 so as to open the line, an intermittent short circuit means 80 for alternately operating the short circuit means 60 and the open means 70, and a DC voltage detection means for detecting the DC voltage of the DC power supply 10. 90.

A configuration of the inverter 40 shown in FIG. 2 will be described.
The inverter 40 includes three IGBT switching elements 100a connected in parallel to the freewheeling diode 110 connected to the positive side of the DC power supply 10 and three connected in parallel to the freewheeling diode 110 connected to the negative side of the DC power supply 10. The IGBT switching element 100b is connected to each other in series, and the neutral point on the positive side and the negative side is connected to each phase of the permanent magnet synchronous motor 30.
Here, the following description will be made assuming that the three positive side switching elements 100a of the DC power supply 10 are upper arms and the three negative side switching elements 100b are lower arms.

Next, the operation of the permanent magnet synchronous motor driving apparatus according to Embodiment 1 of the present invention will be described based on the flowchart of FIG. However, FIG. 5 shows the case where the DC voltage detecting means is used, but the same flowchart is obtained when the AC voltage detecting means and the rotational speed detecting means are used.
The inverter control means 50 controls the inverter 40 based on the output of the DC voltage detection means 90 so as to suppress the regenerative voltage.
That is, when the permanent magnet synchronous motor 30 is stopped driving and all the three positive side switching elements 100a of the upper arm of the inverter 40 and the three negative side switching elements 100b of the lower arm are turned off (this is referred to as an open state). In addition, when the permanent magnet synchronous motor 30 is forcibly rotated, a regenerative voltage is generated.
This regenerative voltage causes a current to flow through the upper and lower arm freewheeling diodes 110 for rectification, and a DC voltage is applied to the DC power supply 10. The DC voltage detection means 90 detects the DC voltage applied to the DC power supply 10 and outputs the detected DC voltage to the inverter control means 50.

  Then, in the inverter control means 50, when the output of the DC voltage based on the regenerative voltage detected by the DC voltage detection means 90 increases and exceeds the short-circuit threshold that is the first threshold (step S1), the short-circuit means 60 is changed. As shown in FIG. 3A, control is performed so that all the upper arms 100a of the inverter 40 are turned on, and the line between the inverter 40 and the permanent magnet synchronous motor 30 is short-circuited, or FIG. As shown in (b), all the lower arms 100b of the inverter 40 are turned on to short-circuit the line between the inverter 40 and the permanent magnet synchronous motor 30 (step S2), and the generated regenerative voltage is used as the permanent magnet synchronous motor 30. The regenerative voltage is lowered by consuming it in the interior.

Thus, when the line between the inverter 40 and the permanent magnet synchronous motor 30 is short-circuited, regenerative energy is not supplied to the DC power supply 10, but the DC voltage of the DC power supply 10 is, for example, that of the inverter control means 50. Since it is supplied as an operating voltage, it is consumed there and gradually decreases.
Then, in the inverter control means 50, when the output of the direct current voltage based on the regenerative voltage detected by the direct current voltage detection means 90 falls and falls below the open threshold value which is the second threshold value (step S3), it is shown in FIG. As described above, the above-described short-circuit state is canceled by turning off all the upper arms 100a of the inverter 40 that have been turned on or turning off all of the lower arms 100b that have been turned on until now. All the arms 100b are turned off to be opened (step S4).

Then, as shown in FIG. 6, the regenerative voltage rises again, and if the DC voltage based on the regenerative voltage also rises to reach the first threshold value, the process returns to step S2 to be short-circuited.
As described above, the regenerative voltage generated when the permanent magnet synchronous motor 30 is forcibly rotated by repeating the short circuit and the open operation between the lines of the inverter 40 and the permanent magnet synchronous motor 30 is less than the withstand voltage of the inverter 40. It becomes possible to suppress the breakdown voltage breakdown of the switching elements constituting the inverter 40 and the like.

However, as described above, when the short-circuit threshold value and the open-circuit threshold value of the DC voltage that are short-circuited and opened by the short-circuit means 60 and the open-circuit means 70 are approximately the same, short-circuit and open operations frequently occur and permanent magnet synchronization occurs. There is a problem that noise occurs in the current flowing through the motor 30.
Therefore, the short-circuit threshold value for starting the short-circuit operation and the open-circuit threshold value for starting the open-circuit operation are not made substantially the same value, and the short-circuit threshold value is set to the open-threshold value so that the short-circuit threshold value is greater than the open-circuit threshold value. Since frequent opening operations can be suppressed and noise generation can be reduced, it is possible to obtain a highly reliable permanent magnet synchronous motor driving device free from malfunctions due to noise.
However, it is better to have a certain voltage difference between the short-circuit threshold and the open threshold so that noise or the like does not occur. The DC voltage waveform at that time is shown in FIG.

However, when the line between the permanent magnet synchronous motors 30 shifts from the open operation to the short circuit operation, a current about twice as large as the steady state flows through the permanent magnet synchronous motor 30 instantaneously.
When a large current flows through the permanent magnets constituting the permanent magnet synchronous motor 30, the magnetic force may decrease and the performance may deteriorate.
Therefore, before the line between the permanent magnet synchronous motor 30 shifts from the open operation to the short circuit operation, the short circuit and the open circuit are alternately operated in a short time by the intermittent short circuit means 80 to perform the intermittent short circuit operation. The current that flows instantaneously can be suppressed by performing the short-circuit operation by the short-circuit means 60 after performing the short-circuit operation intermittently while gradually increasing the time to be performed.
FIG. 7 shows switching waveforms of the upper arm 100a or the lower arm 100b of the inverter 40 when shifting to a short circuit, intermittent short circuit, and open operation. Further, as shown in FIG. 7, the intermittent short-circuit operation time t can be arbitrarily designed.
Further, the intermittent short-circuit means 80 may be controlled so as to gradually increase the short-circuit time as time passes by a timer or the like, or the duty may be gradually increased by using PWM to increase the short-circuit time.

Further, as a means having the same function as the short-circuit means 60, the open means 70 and the intermittent short-circuit means 80 of the inverter control means 50, according to the deviation between the output of the DC voltage detection means 70 and a preset DC voltage command value. In some cases, the ratio of the short-circuiting and opening operation times is varied to control the DC voltage to be constant.
For example, as shown in FIG. 8, the DC voltage command value is positive and the output detected by the DC voltage detecting means 90 is negative and added by the adder 119. The deviation is input to the controller 120, and the deviation is eliminated. Controls the ratio of short and open operation time.
In this case, if the opening operation time is set to 0 and only the short-circuiting operation time is controlled, it functions in the same manner as the short-circuit means 60. Conversely, the short-circuiting operation time is set to 0 and only the opening operation time is controlled. If it does so, it will function as the said open | release means 70, and if it sets an open operation time and a short circuit operation time to a fixed ratio, it will function as the intermittent short circuit means 80.
As shown in FIG. 9, the controller 120 may use, for example, a PID controller that performs proportional operation, integration operation, and differentiation operation. Of course, it is sufficient if the control can be performed so as to eliminate the deviation, and it goes without saying that another controller can be substituted.

Thereby, even when the constant of the permanent magnet synchronous motor 30 changes, it is possible to prevent the magnetic force of the permanent magnet from being weakened by controlling the ratio of the short-circuiting and opening operation time according to the deviation. Can be expected.
Further, for example, by adjusting the response by changing the gains of the proportional operation, integral operation and differential operation of the PID controller, the ratio of the short-circuiting and opening operation time is gradually changed, which is equivalent to the intermittent short-circuit means described above. An effect can be obtained.
As a result, it is possible to suppress an instantaneous current at the time of transition from the open state to the short circuit state, to suppress a decrease in magnetic force of the permanent magnet synchronous motor 30, and to obtain a highly reliable permanent magnet synchronous motor drive device. it can.

The following description is supplemented for the inverter 40 and the inverter control means 50 described in the first embodiment.
Inverter 40 is IGBT switching elements 100a and 100b as shown in FIG. 3, but there is no problem with other switching elements such as MOSFETs.
Further, although the inverter 40 is a three-phase bridge circuit as shown in FIG. 3, it is controlled by the inverter control means 50 so as to perform a short circuit and an open operation even in the case of two phases or a plurality of bridge circuits. It goes without saying that the same result can be obtained by inputting a signal.

  Furthermore, there is a problem that the inverter control means 50 cannot operate when power is not supplied from the DC power supply 10. However, if the regenerative voltage generated when the permanent magnet synchronous motor 30 is forcibly rotated becomes equal to or greater than a predetermined value, the same effect as that obtained when the power is supplied by the DC power supply 10 can be obtained. Become.

Further, when all of the upper arm 100a or the lower arm 100b of the inverter 40 are turned on and the inverter control means 50 is short-circuited, the upper arm 100a that has been on until now or has been on until now after a predetermined time has elapsed. All the lower arms 100b are turned off, and all the upper arms 100a and the lower arms 100b are turned off to be in an open state.
Thereby, for example, when the short-circuit state cannot be stopped for some reason, such as when the DC power supply 10 supplies an abnormal threshold voltage that causes a short-circuit operation, or in an operation in which the short-circuit state continues for a long time (several seconds to several tens of minutes, etc.) It is possible to prevent the permanent magnet synchronous motor 30 from reaching a high temperature and reducing the energy saving performance due to an increase in the winding resistance of the permanent magnet synchronous motor 30 and the magnetic force of the permanent magnet of the permanent magnet synchronous motor 30 from being easily weakened.

  Further, when the inverter control means 50 performs a short circuit operation by turning on either the upper arm 100a or the lower arm 100b of the inverter 40, switching is performed by alternately turning on the upper arm 100a and the lower arm 100b. The temperature rise of the element can be suppressed. As a result, it is possible to prevent a load from being applied to only one of the switching elements, and an effect can be expected to prevent aged deterioration.

Further, when all of the upper arm 100a and the lower arm 100b of the inverter 40 are turned on and the inverter control means 50 is short-circuited, the inverter control means 50 is a temperature detection means (not shown) from a temperature detection element such as a thermistor. The upper arm 100a or the lower arm 100b is turned off according to the temperature obtained and the temperature estimated value obtained by calculation from the current flowing through the inverter 40 and the permanent magnet synchronous motor 30. As a result, the permanent magnet synchronous motor 30 becomes high temperature and energy is saved. It is possible to prevent the performance from being deteriorated and the permanent magnet of the permanent magnet synchronous motor 30 from being easily weakened.

Embodiment 2
FIG. 10 is a block diagram of a permanent magnet synchronous motor driving apparatus according to Embodiment 2 of the present invention.
In FIG. 10, 10 is a DC power source, 20 is a motor drive device, 30 is a permanent magnet synchronous motor, 40 is an inverter, 50 is inverter control means, 60 is short-circuit means, 70 is open means, and 80 is short-circuit means.
Between the inverter 40 and the permanent magnet synchronous motor 30, AC voltage detection means 130 for detecting the AC voltage output from the inverter 40 is provided.
In the second embodiment, the DC voltage detecting means 90 shown in FIG. 1 of the first embodiment is replaced with an AC voltage detecting means 130, and the other configurations are the same.
That is, the only difference from the description of the first embodiment is that the physical quantity taken into the inverter control means 50 changes from a DC voltage to an AC voltage, and the first threshold value and the second threshold value become an AC voltage value. 40 and the inverter control means 50 operate in the same manner, and therefore redundant description is omitted.

Embodiment 3
FIG. 11 is a block diagram of a permanent magnet synchronous motor driving apparatus according to Embodiment 3 of the present invention.
In FIG. 11, 10 is a DC power source, 20 is a motor drive device, 30 is a permanent magnet synchronous motor, 40 is an inverter, 50 is an inverter control means, 60 is a short-circuit means, 70 is an open means, 80 is an intermittent short-circuit means, and 140 is It is a rotational speed detection means for detecting the rotational speed of the permanent magnet synchronous motor 30.
In the third embodiment, the DC voltage detection means 90 shown in FIG. 1 of the first embodiment is replaced with a rotation speed detection means 140, and the other configurations are the same.
That is, the only difference between the description of the first embodiment is that the physical quantity taken into the inverter control means 50 becomes the rotational speed from the DC voltage, and the first threshold value and the second threshold value become the rotational speed. Since the operation in the inverter control means 50 is the same, redundant description is omitted.

Embodiment 4
FIG. 12 is a block diagram of a driving apparatus for a permanent magnet synchronous motor according to Embodiment 4 of the present invention, and FIG. 13 is another block diagram of the driving apparatus for the permanent magnet synchronous motor.
In FIG. 12, 10 is a DC power source, 20 is a motor drive device, 30 is a permanent magnet synchronous motor, 40 is an inverter, 50 is an inverter control means, 60 is a short-circuit means, 70 is an open means, 80 is an intermittent short-circuit means, and 90 is DC voltage detecting means, 130 is AC voltage detecting means, and 140 is a rotational speed detecting means.

As described above, the inverter control means 50 is based on the outputs of the DC voltage detection means 90 in the first embodiment, the AC voltage detection means 130 in the second embodiment, and the rotation speed detection means 140 in the third embodiment. Short-circuiting, intermittent short-circuiting, and opening operations were performed by the short-circuiting means 60, the opening means 70, and the intermittent short-circuiting means 80.
However, each detection means does not function for some reason, and at the same time, short circuit, intermittent short circuit, open operation cannot be performed, and the regenerative voltage generated when the permanent magnet synchronous motor 30 is forcibly rotated cannot be suppressed. Sufficient safety cannot be secured.
Therefore, as shown in FIG. 12, three detection means 90, 130, 140 are used simultaneously, and the inverter control means 50 operates the short-circuit means 60 and the release means 70 based on the output of at least one detection means that is not malfunctioning. By performing the short circuit and opening, the inverter circuit 40 can be protected with higher reliability.
Further, the inverter control means 50 operates the short-circuit means 60, the intermittent short-circuit means 80, and the opening means 70 so as to perform short-circuiting, intermittent short-circuiting, and opening, so that the inverter circuit 40 can be protected with higher reliability. In addition, by performing the intermittent short-circuit operation, it is possible to suppress a current that flows instantaneously when shifting from the open operation to the short-circuit operation.
In this case, if the output of one detection means is used, the output of the other detection means is not used.

Also, the inverter control means 50 is based on one increasing output among the outputs of two detection means preselected from the three detection means of the DC voltage detection means 90, the AC voltage detection means 130 and the rotational speed detection means 140. By operating the short-circuit means 60 and the open-circuit means 70 to perform short-circuit and open-circuit, the inverter circuit 40 can be protected with higher reliability.
Further, the inverter control means 50 operates the short-circuit means 60, the intermittent short-circuit means 80, and the opening means 70 so as to perform short-circuiting, intermittent short-circuiting, and opening, so that the inverter circuit 40 can be protected with higher reliability. In addition, by performing the intermittent short-circuit operation, it is possible to suppress a current that flows instantaneously when shifting from the open operation to the short-circuit operation.
Also in this case, if the output of one detection means is used, the output of the other detection means is not used.

As shown in FIG. 13, when a power supply device 150 such as a converter and a load device 160 such as a compressor are connected to the DC voltage detection means 90, the DC voltage detection means 90, the AC voltage detection means 130, and the rotation speed detection means. The two outputs detected by the DC voltage detecting means 90 and the rotational speed detecting means 140 from the three detecting means 140 or the two outputs detected by the DC voltage detecting means 90 and the AC voltage detecting means 130 are both set to the short-circuit threshold. The inverter control means 50 operates the short-circuit means 60, and the inverter control means 50 operates the opening means 70 when the output of the AC voltage detecting means 130 or the rotational speed detecting means 140 falls below the opening threshold. To.
As described above, both the output of the DC voltage generated on the input side of the inverter 40 and the output of the rotational speed or the AC voltage generated on the output side are both detected because the permanent magnet synchronous motor 30 is forcibly rotated from the outside. This is because the DC voltage is boosted, the rotation speed is increased, or the AC voltage is boosted.

Therefore, the DC voltage is not boosted by forcibly rotating the permanent magnet synchronous motor from the outside. For example, as shown in FIG. 13, the power supply device 150 such as a converter connected to the DC voltage detecting means 90 or the compressor When a DC voltage boost that may occur due to an abnormal operation or an emergency stop of the electrical device 160 occurs, the output speed of the inverter 40 or the output of the AC voltage does not occur.
Therefore, the motor drive device is not operated by short-circuiting the DC voltage boost that may occur due to abnormal operation or emergency stop of the power supply device 150 (converter or the like) or the electric device 160 (compressor or the like) as described above. The inverter circuit 40 can be protected with higher reliability without hindering the normal operation of the inverter circuit 40.
Further, the inverter control means 50 operates the short-circuit means 60, the intermittent short-circuit means 80, and the opening means 70 so as to perform short-circuiting, intermittent short-circuiting, and opening, so that the inverter circuit 40 can be protected with higher reliability. In addition, by performing the intermittent short-circuit operation, it is possible to suppress a current that flows instantaneously when shifting from the open operation to the short-circuit operation.

  It goes without saying that the inverter control means 50 in the first to fourth embodiments can be realized by any of an analog circuit, a digital circuit, and a microcomputer.

  As described above, examples of utilizing the motor driving device described in the first to fourth embodiments include an air conditioner, a ventilation fan, a washing machine, an automobile, and a vehicle.

The block diagram of the drive device of the permanent-magnet synchronous motor which concerns on Embodiment 1 of this invention. The circuit diagram of the three-phase bridge of the inverter of the drive device of the permanent magnet synchronous motor. The circuit diagram of the short circuit operation state of the inverter of the drive device of the permanent magnet synchronous motor. The circuit diagram of the open operation state of the inverter of the drive device of the permanent magnet synchronous motor. The flowchart of the short circuit of the inverter of the drive device of the permanent magnet synchronous motor, and open | release operation. The DC voltage waveform figure by the short circuit of the inverter of the drive device of the permanent magnet synchronous motor, and open | release operation. Explanatory drawing which shows the switching waveform at the time of the open of the inverter of the drive device of the permanent magnet synchronous motor, an intermittent short circuit, and an open operation. The block diagram which shows the ratio control of the short circuit of the inverter of the drive device of the permanent magnet synchronous motor, and an open operation time. The block diagram which shows the internal structure of the controller of the drive device of the permanent magnet synchronous motor. The block diagram of the drive device of the permanent-magnet synchronous motor which concerns on Embodiment 2 of this invention. The block diagram of the drive device of the permanent-magnet synchronous motor which concerns on Embodiment 3 of this invention. The block diagram of the drive device of the permanent-magnet synchronous motor which concerns on Embodiment 4 of this invention. The other block diagram of the drive device of the permanent magnet synchronous motor.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 DC power supply, 20 Motor drive device, 30 Permanent magnet synchronous motor, 40 Inverter, 50 Inverter control means, 60 Short circuit means, 70 Opening means, 80 Intermittent short circuit means, 90 DC voltage detection means, 100a Positive side switching element (upper arm ), 100b negative side switching element (lower arm), 110 freewheeling diode, 119 adder, 120 controller, 130 AC voltage detecting means, 140 rotational speed detecting means, 150 power supply device, 160 load device.

Claims (10)

An inverter that takes the DC voltage of the DC power supply as input and outputs the voltage to the permanent magnet synchronous motor;
DC voltage detecting means for detecting a DC regenerative voltage appearing on the input side of the inverter;
Inverter control means for controlling the voltage output from the inverter,
The inverter control means, during regenerative operation,
Short-circuiting means for controlling the inverter so as to short-circuit the line between the inverter and the permanent magnet synchronous motor based on the increasing regenerative voltage detected by the DC voltage detection means;
An opening means for controlling the inverter so as to open a line between the inverter and the permanent magnet synchronous motor based on a decreasing regenerative voltage detected by the DC voltage detecting means;
Intermittent short-circuit means for controlling the inverter so as to alternately open and short-circuit the line between the inverter and the permanent magnet synchronous motor based on the increasing regenerative voltage detected by the DC voltage detection means;
Equipped with a,
When the increasing regenerative voltage detected by the DC voltage detecting means exceeds a first threshold, the intermittent shorting means is operated, and then the shorting means is operated, and the decreasing regenerative detection detected by the DC voltage detecting means is performed. The permanent magnet synchronous motor driving apparatus , wherein the opening means is operated when a voltage falls below a second threshold value . The intermittent short-circuit means includes
The driving device for a permanent magnet synchronous motor according to claim 1 , wherein a short-circuiting time when the permanent magnet synchronous motor is intermittently short-circuited is gradually increased. The inverter is composed of a plurality of positive side switching elements connected to the positive side of the DC power source and a plurality of negative side switching elements connected to the negative side of the DC power source,
The short-circuit means is configured to turn on all of the positive-side switching element or the negative-side switching element,
The permanent magnet synchronous motor drive device according to claim 1 or 2 , wherein the opening means is configured to turn off all of the positive side switching element and the negative side switching element. The inverter is composed of a plurality of positive side switching elements connected to the positive side of the DC power source and a plurality of negative side switching elements connected to the negative side of the DC power source,
The short-circuit means is configured to alternately turn on all of the positive-side switching elements and all of the negative-side switching elements,
The permanent magnet synchronous motor drive device according to claim 1 or 2 , wherein the opening means is configured to turn off all of the positive side switching element and the negative side switching element. The said inverter control means is implement | achieved by an analog circuit, a digital circuit, or a microcomputer. The drive device of the permanent-magnet synchronous motor as described in any one of Claims 1-4 characterized by the above-mentioned. An air conditioner comprising the permanent magnet synchronous motor driving device according to any one of claims 1 to 5 . A drive device for a ventilation fan, wherein the drive device for a permanent magnet synchronous motor according to any one of claims 1 to 5 is mounted. A washing machine comprising the permanent magnet synchronous motor driving device according to any one of claims 1 to 5 . An automobile comprising the permanent magnet synchronous motor driving device according to any one of claims 1 to 5 . A vehicle comprising the permanent magnet synchronous motor drive device according to any one of claims 1 to 5 .

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