JP2002374700A - Permanent magnet synchronous motor drive gear and washing machine using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a permanent magnet synchronous motor drive gear that stably supplies electric power to a control circuit, etc., by fixing a DC voltage, by controlling the number of revolutions of a permanent magnet synchronous motor during power supply interruption, and at the same time, shortens the decelerating time of the motor by controlling the deceleration of the motor. SOLUTION: This drive gear is provided with an inverter circuit which inputs DC power, the permanent magnet synchronous motor connected to the inverter circuit, and a number-of-revolutions control circuit which controls the number of revolutions of the motor, a power supply interruption detecting circuit, which is supplied with control power from the DC power and detects the supply interruption of the DC power and a power supply interruption operating circuit which controls the number of revolutions of the motor, so that a DC voltage becomes a prescribed value, when power supply is interrupted. The drive gear secures the control power, and at the same time, continues the control of the number of revolutions of the motor, by using the power supply interruption operating circuit when power supply is interrupted, and at the same time, restores the number of revolutions of the motor, when the power supply is restored.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor driving apparatus for driving a permanent magnet synchronous motor by an inverter circuit, and more particularly, to controlling the number of rotations of the motor at the time of a power outage so that the rotational energy of the motor is converted to the DC side of the inverter circuit. Regenerate to
The present invention relates to a motor drive device that suppresses a decrease in the DC voltage.

[0002]

2. Description of the Related Art Many motor driving devices using an inverter use a DC voltage on the input side of the inverter as a power source for a control circuit and the like of the motor driving device. Further, an ultra-high-speed motor driving device that performs ultra-high-speed rotation such as an air compressor uses a magnetic bearing device that magnetically levitates and holds a rotor, and may use the DC voltage as a power source of the magnetic bearing device. .

[0003] In these motor driving devices, power is not supplied at the time of a power failure. Therefore, when the DC voltage decreases, measures are taken to stop the driving of the motor or to secure the power using a battery. In particular, in an ultrahigh-speed motor driving device, it is necessary to supply power to the magnetic bearing device until the rotation speed decreases, and it is necessary to set a large capacity of the battery.

However, since the battery requires maintenance and the circuit scale becomes large, for example, as shown in JP-A-6-280874 and JP-A-59-23098, the motor is operated at the time of power failure. A method is disclosed in which a rotating energy is regenerated to a direct current side and supplied to a magnetic bearing device or the like so that a battery is not required.

[0005]

The above-mentioned prior art is a method using the regenerative electric power of the motor at the time of a power failure. However, there is no study on the control of the rotation speed of the motor at the time of the power failure. When the driving of the motor is stopped at the time of the power failure, the motor is rotated by inertia, so that sufficient deceleration control is not performed and the stopping time becomes longer. Further, when the power failure is recovered during the deceleration, a rotor positioning process (restartup process) from the rotation speed is required. Further, since the magnitude of the DC voltage is determined by the amount of energy regenerated, the DC voltage cannot be controlled to be constant.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, to control the number of rotations of a motor during a power failure, to control the DC voltage to be constant, and to stably supply power to a control circuit and the like.
As described above, simultaneously with the stable supply of the electric power, the deceleration control of the motor is performed to shorten the deceleration time.

[0007] Another object of the present invention is to recover the power failure and recover the rotation speed immediately by continuing the rotation speed control of the motor.

Still another object of the present invention is to provide a motor drive device which prepares a plurality of motor control modes at the time of a power failure, switches the control mode according to the length of the power failure time, performs an optimal power failure process, and uses the motor drive device. It is to improve the usability of the system.

[0009]

A motor driving apparatus according to the present invention controls an inverter circuit to which DC power is input, a permanent magnet synchronous motor connected to the inverter circuit, and a rotation speed of the permanent magnet synchronous motor. Rotation speed control circuit, and the DC power is used as a control power supply of the present apparatus,
A power failure detection circuit that detects the stop of the supply of the DC power, and a power failure operation circuit that controls the rotation speed of the permanent magnet synchronous motor so that the DC voltage becomes a predetermined value at the time of a power failure. The control of the rotation speed of the permanent magnet synchronous motor is performed by using the power supply for the control and the continuation of the control of the rotation speed of the permanent magnet synchronous motor at the same time. Let it.

Further, the motor driving apparatus of the present invention uses a power failure operation circuit for reducing the number of revolutions of the permanent magnet synchronous motor so that the DC voltage becomes a predetermined value at the time of power failure, to secure the power of the control power supply. The rotation speed of the permanent magnet synchronous motor can be reduced. Thereby, the deceleration control of the motor can be performed to reduce the deceleration time.

The motor drive device of the present invention is applied to a washing machine that drives a washing tub with a permanent magnet synchronous motor, to secure a control power supply for controlling the entire washing machine in the event of a power failure, and to continue operating the rotation speed control circuit. At the same time, the operation of the washing machine can be maintained.

Further, the motor driving device of the present invention is applied to an ultra-high-speed rotating motor driving device provided with a magnetic bearing circuit for magnetically levitating and holding a rotor of a permanent magnet synchronous motor. While securing the power of the, and rapidly reducing the rotation speed of the permanent magnet synchronous motor,
An auxiliary power supply for a magnetic bearing device such as a battery can be omitted or the capacity of the auxiliary power supply can be reduced, and speed reduction control can be quickly performed at a rotation speed that does not require magnetic levitation.

Further, in the motor driving device and the washing machine of the present invention, a normal operation mode in which the number of revolutions of the permanent magnet synchronous motor is controlled to a predetermined value, and a DC voltage is reduced by decreasing the number of revolutions of the permanent magnet synchronous motor. The power failure continuation operation mode in which the power supply is controlled to a predetermined value and the power failure standby mode in which the operation of the permanent magnet synchronous motor is stopped and the DC voltage is prevented from dropping, the length of the power supply suspension time, the permanent magnet synchronous motor By selecting a control mode using at least one control condition of a rotation speed and a DC voltage value and controlling the permanent magnet synchronous motor, an optimal power failure process is performed to improve the usability of a motor drive device and a system using the same. Let it. Also in the power failure standby mode, the motor drive device and the control circuit of the washing machine of the present invention are operating, and the phase information of the permanent magnet synchronous motor can be updated to prepare for power recovery.

[0014] A motor driving device according to the present invention includes an inverter circuit to which DC power is input, a permanent magnet synchronous motor connected to the inverter circuit, and a rotational speed control circuit for controlling the rotational speed of the permanent magnet synchronous motor. A phase update circuit that updates the phase of the permanent magnet synchronous motor with rotation of the permanent magnet synchronous motor, and a supply of the DC power is stopped in a motor drive device that uses the DC input power as a control power supply of the present device. Power failure detection circuit to detect
In the event of a power failure, the output of the inverter circuit is shut off to secure the power of the control power supply, and the phase update circuit updates the phase of the permanent magnet synchronous motor to provide a power failure standby mode for power recovery.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to the drawings.

<Embodiment 1> A case where the present invention is applied to a motor control device for driving a washing tub of a washing machine will be described with reference to FIGS. FIG. 1 is a block diagram of a motor control device for driving a washing tub. Generally, a washing machine rectifies a commercial AC power supply to obtain a DC power supply. However, the present embodiment also has a similar circuit, and uses the rectifier circuit 9 to generate DC power. Here, a power factor improving circuit for improving the power factor may be installed on the output side of the rectifier circuit 9, or a circuit such as a battery that can directly obtain DC power may be connected. As a power supply for each control circuit of the motor control device as shown in FIG. 1, a DC 5 V or 15 V is generally used, and these power supplies use a DC-DC converter which is a DC-DC power supply 10 from the DC power. Has been created.

The motor control device comprises a rectifier circuit 9, a DC-D
C power source 10, an inverter main circuit 1 to which DC power is input, a permanent magnet synchronous motor 2 connected to an output terminal of the inverter main circuit 1 to drive the washing tub 3, and a motor current of the permanent magnet synchronous motor, A control circuit 6, which controls the inverter main circuit 1 by dividing the system into d-axis components and q-axis components, a rotation speed calculation circuit 4, which detects position information of the permanent magnet synchronous motor 2 and calculates a rotation speed, Arithmetic circuit 4
A rotation speed control circuit 5 for calculating a q-axis current command from the calculated value of the rotation speed and the rotation speed command value to control the rotation speed of the permanent magnet synchronous motor 2, and a DC voltage which is an input of the inverter main circuit 1 is detected. Power failure detection circuit 8 that detects a power failure due to a drop in power
And a power failure operation for detecting the DC voltage when the power failure is detected by the output signal of the power failure detection circuit 8 and changing a rotation speed command value to the rotation speed control circuit 5 so that the DC voltage becomes a predetermined value. It comprises a circuit 7.

Here, the position information of the permanent magnet synchronous motor may be estimated using a sensor such as a Hall element, or from information such as an induced voltage, a terminal voltage, and a motor current. Also,
When operating as a synchronous motor, the number of rotations need not be fed back. Further, the control circuit 6 receives the d-axis current command value as 0, but this is a case where the permanent magnet synchronous motor 2 is assumed to be a non-salient-pole type motor. It may be changed arbitrarily, such as when a salient pole type motor is used.

The control circuit 6 uses the position information, the q-axis current command value Iq ^* and the d-axis current command value Id ^* from the rotation speed control circuit 5 and the calculation value of the rotation speed calculation circuit 4 to generate the permanent magnet. The motor current of the synchronous motor 2 is controlled.
In the present embodiment, an open loop type vector control method in which a voltage applied to the permanent magnet synchronous motor 2 is determined by using a motor model from the current command value is assumed. Current control may be performed such that a flowing motor current is detected, the motor current is dq-converted, and the command current is matched.

The rotation speed control circuit 5 calculates a q-axis current command value from the deviation between the command rotation speed and the calculated rotation speed using proportional integral control. The power failure detection circuit 8 compares the DC voltage value with a set value, determines that a power failure has occurred when the DC voltage value is lower than the set value, and outputs a power failure signal. Here, the set values have different hysteresis values before and after the power failure. In the present embodiment, the power failure is determined from the DC voltage. However, there is no problem if the power failure is detected using the AC voltage value or the zero cross signal of the AC voltage.

The power failure operation circuit 7 includes the power failure detection circuit 8
In accordance with the output signal of the above, it is selected whether to output the normal rotation speed command value N ^{* as it is} to the rotation speed control circuit 5 or to change the rotation speed command value so as to control the DC voltage to a predetermined value. I do. At the time of a power failure, the rotation speed command value is changed so that the DC voltage becomes a predetermined value, and the DC voltage is controlled. In this embodiment, DC voltage control is performed by proportional integral control based on a deviation between a set value and a DC voltage value.

In order to maintain the DC voltage at the set value in the event of a power failure, it is necessary to regenerate the rotational energy of the permanent magnet synchronous motor 2 to the power supply side. Control. For this reason,
The rotation speed of the permanent magnet synchronous motor 2 decreases rapidly. When the power is restored, the permanent magnet synchronous motor 2 is re-accelerated to return to the normal rotational speed command value. Further, the rectifier circuit 9 such as the control circuit 6 and the rotation speed control circuit 5 is connected to the DC-D
The control circuit 6 other than the C power supply 10 and the inverter main circuit 1, the rotation speed control circuit 5, and the like are realized by software processing using a one-chip microcomputer or DSP.

FIG. 2 shows a switching speed control method switching algorithm using the power failure detection circuit 8 and the power failure operation circuit 7. In FIG. 2, controlling the rotation speed of the permanent magnet synchronous motor 2 using the normal rotation speed command value N ^* is referred to as normal operation control, and controlling the rotation speed using the power failure operation circuit 7 is referred to as power failure continuation operation control. Call.

First, in step (a), it is determined whether the permanent magnet synchronous motor 2 is performing the power failure continuation operation control. If during normal operation control, go to step (i),
If the power failure continues, the process proceeds to step (e).

When the process proceeds to step (i), the set value used for comparison with the DC voltage of the power failure detection circuit 8 is, for example, 1
If the DC voltage value is set to 00 V, the power failure detection circuit compares the DC voltage value with a set value (100 V). If the DC voltage value is equal to or less than the set value, it is determined that a power failure has occurred. Control the operation. Specifically, the command value of the number of revolutions is calculated by the proportional integral control so that the DC voltage becomes the set value Ed1 ^* using the power failure operation circuit 7. If the DC voltage value is equal to or higher than the set value (100 V), it is determined that there is no power failure, and the process proceeds to step (O) to continue the normal operation control.

When the process proceeds to step (e), the power failure continuation operation control is currently being performed, so the power failure detection circuit 8 needs to detect the timing of power recovery. Therefore, the set value to be compared with the DC voltage must be higher than that at the time of power failure detection and higher than the DC voltage set value at the time of power failure continuation operation control. In this embodiment, the DC voltage set value during the power failure continuation operation control is set to the same value (100 V) as the set value for power failure detection.
Therefore, the set value for power recovery detection is set to the set value for power failure detection + 5 V (105 V). If the DC voltage value is equal to or higher than the above value (105 V), it is determined that the power is restored, and the operation is switched to the normal operation control.

As described above, the power failure and the power recovery are detected, the DC voltage is maintained at the set value at the time of the power failure, the rotation speed control of the motor and the stop of the motor control circuit are suppressed, and the predetermined rotation speed is simultaneously achieved with the power recovery. It is possible to control the number of revolutions to accelerate quickly.

FIG. 3 shows a temporal transition of the DC voltage and the number of rotations of the motor when the above control is performed. FIG. 3A shows a case where the power failure continuation operation control is not performed, in other words, a case where the control during the power failure is performed only by the normal operation control, and FIG. 3B shows a case where the power failure continuation operation control is performed. In both cases, the power is cut off at t0 and the power is restored at t3. Further, the transition of the DC voltage and the motor speed when the power is not restored is shown by a dotted line.

The operation of the present invention when the continuous power failure operation is not performed will be described with reference to FIG. When a power failure occurs at time t0, the open-loop control without current control is performed, so that the rotation speed decreases. At this time,
Since the control system tries to maintain the rotation speed, the DC power stored in the smoothing capacitor is consumed, and the DC voltage rapidly decreases. When the power is restored at time t3, the DC voltage returns to the original state, and the rotation speed also increases. If the power is not restored at time t3, the DC power is further reduced to stop the energization of the motor at time t5 when the voltage reaches the voltage shortage stop level which is the protection level of the apparatus.

The voltage shortage stop level is a level at which the power supply of the control circuit of the motor control device cannot be maintained.
When the motor is driven any more, proper control cannot be performed. For this reason, the drive of the motor is stopped to prepare for the power reset of the control circuit. Here, if the rotation speed control of the motor is completely stopped, after the power is restored, the motor must be started again, and it takes time to restart.
There is also an operation method of accelerating from the rotation speed during the rotation, but additional processing such as calculation of the initial rotation speed and detection of the rotational position of the rotor is required, and the processing time is long.

The operation when the power failure continuation operation control of this embodiment is used will be described with reference to FIG. In the case where a power failure occurs at time t0, FIG.
The normal operation control is performed in the same manner as described above, and the DC voltage decreases.
When the DC voltage value reaches the power failure detection set level at time t1, power failure continuation operation control is started, and the rotational energy of the motor is regenerated to maintain the DC voltage at the set value. At this time,
The rotation speed of the motor decreases rapidly and becomes low after time t2, and the control of the rotation speed of the motor is maintained while suppressing the consumption of DC power.

When the power is restored at time t3, the DC voltage rises, so that the motor speed is also controlled to increase. When the power failure detection circuit 8 detects the power restoration at time t4, the control method is switched to the normal operation control. Sudden acceleration is performed from the rotation speed at that time, and the rotation speed can be returned to the rotation speed before the power failure. If the power failure does not recover, the motor speed gradually decreases. Eventually, when the rotation speed command becomes 0 or the DC voltage value reaches the voltage shortage level, the rotation speed control of the motor is stopped. According to this embodiment, the time until the driving of the motor is stopped can be lengthened,
When the power is restored, the vehicle can quickly accelerate and return to the original state.

<Embodiment 2> In this embodiment, the case of securing DC power and rapidly decelerating the motor will be described using an example of an ultrahigh-speed motor control device such as an air compressor that rotates at an ultrahigh speed.

A motor that rotates at an ultra-high speed uses a magnetic bearing that magnetically levitates and holds the rotor. Such a device is equipped with a battery to cope with the power failure because the power supply of the magnetic bearing must be secured even if a power failure occurs, but as described in the previous example, the battery needs maintenance. However, there is a problem that the scale of the device becomes large. In view of the above, the above-mentioned conventional technology in which the rotational energy of the motor is regenerated and used as a power source for the magnetic bearing is disclosed, but the deceleration control of the motor is not described in detail.

In an ultra-high-speed motor drive device using a magnetic bearing, it is important to secure a power source for the magnetic bearing device and to quickly reduce the rotational speed to a speed at which the magnetic bearing does not need to be used. In addition, it is also important that the vehicle be quickly accelerated after the power outage is recovered and return to the original rotation speed. In particular, since it takes time to accelerate to ultra-high speed rotation, it is necessary to accelerate simultaneously with the restoration of power.

This embodiment will be described with reference to FIGS.
This embodiment is different from the first embodiment in a washing tub 3 of a washing machine.
And the magnetic bearing device 11 is added instead. The power failure detection circuit 80 detects directly from the AC power source instead of the DC voltage, and the set voltage value of the power failure operation circuit 70 is Ed2.
^* The magnetic bearing device 11 uses DC power.

FIG. 5 shows an operation comparison diagram similar to FIG. FIG.
(A) shows a temporal change of the DC voltage and the number of rotations when the power supply to the motor is stopped at the time of the power failure and the rotational energy of the motor is regenerated. FIG. 5 also shows a case where a power failure occurs at time t0 and power is not restored, similarly to FIG. When the power failure detection circuit 80 detects a power failure at time t1, the driving of the motor is stopped. However, since the regeneration for controlling the regenerative power is not performed, the DC voltage becomes a voltage corresponding to the induced voltage of the motor. The DC voltage gradually decreases in proportion to the rotation speed of. In other words, the decrease in the DC voltage is suppressed, but the DC voltage gradually decreases without being controlled to a constant value. Further, the speed of decrease in the number of rotations is slow. For this reason, it takes time until the rotation speed of the motor becomes a rotation speed that does not require magnetic levitation.

FIG. 5 (b) shows a temporal transition diagram of the DC voltage and the number of revolutions in this embodiment. FIG. 5 (b) is basically the same as FIG. 3 (b), except that the DC voltage set value E during the continuous power failure operation is set.
The difference is that d2 ^* is higher than the normal DC voltage value.
This aims to shorten the deceleration time by increasing the amount of brake torque generated. Here, the setting of the DC voltage set value Ed2 ^* during the continuous power failure operation depends on the inverter main circuit 1 and the DC-
What is necessary is just to make it not exceed the maximum voltage allowable value of the DC power supply 10 or the like.

As is apparent from a comparison between FIG. 5A and FIG. 5B, according to this embodiment, the DC voltage can be controlled to a predetermined value, and the deceleration time of the motor can be reduced. This allows
The power supply of the magnetic bearing device in the ultra-high-speed rotation motor driving device can be ensured, and at the same time, the deceleration time can be shortened and the rotation speed can be controlled to a safe rotation speed that does not require magnetic levitation. Further, as in the first embodiment, since the rotation speed control is performed until the motor stops, the acceleration can be performed again at the same time when the power is restored.

Further, in the present embodiment, it has been described that the stop time of the motor can be shortened by performing the power failure continuous operation at the time of the power failure, but the present invention can also be applied to the motor stop processing at the normal time. That is, if the present invention is applied when the motor is stopped, the stop time can be shortened by keeping the DC voltage constant, so that an overvoltage during deceleration of the motor can be prevented.

In the present embodiment, an ultra-high-speed motor control device using magnetic bearings has been described as an example. However, the present invention is also applicable to the washing machine described in the first embodiment. The operation of the washing machine is "wash"
There are three operations of “rinse” and “dehydration”. During dehydration, the motor is rotating at high speed and it is necessary to stop the motor quickly to ensure the safety of the user. Can be performed.

<Embodiment 3> This embodiment will be described with reference to FIGS. In the present embodiment, when a power failure occurs, the operation control mode of the motor is switched according to the duration of the power failure, thereby reducing the number of resets of the washing machine system and the like, and improving the usability of the system.

FIG. 6 shows a block diagram of this embodiment. FIG.
The same reference numerals perform the same operations. The power failure detection circuit 800 detects the power failure from the DC voltage as in the first embodiment, but measures the time of the power failure period at the same time as the detection of the power failure, and outputs a switching signal at a preset time. The power failure operation circuit 700 switches the control mode according to the switching signal. Specifically, the circuit configuration is such that a stop control for stopping the control of the number of rotations of the motor is added to the power failure operation circuit 7 shown in the first embodiment.

When the above-described configuration is used, the DC voltage, the number of rotations, the operation mode of the entire washing machine, the motor drive signal,
FIG. 7 shows a time transition of the reset signal of the control microcomputer and the timer value for measuring the power failure time. FIG. 7 is also similar to FIG.
A power failure occurs at 0. Here, the DC voltage and the motor rotation speed from time t0 to t3 are the same as those in FIG.

When a power failure is detected at time t1, the power failure detection circuit 800 starts a power failure time measurement timer and starts measuring the power failure time. This timer is reset when the motor drive is stopped or the power failure is recovered, and the counting is stopped.

If the power failure does not recover before time t3, the power failure continuation operation is continued as it is in the first embodiment. However, in the present embodiment, the above-described power failure time measurement timer value is set to a preset motor drive stop time. , The motor drive signal is stopped. By stopping the driving of the motor, the control power of the entire washing machine is secured. As a result, the microcomputer that controls the entire system can be prevented from being reset while minimizing the consumption of DC power. In FIG. 7, the microcomputer reset signal is generated in a relatively short time, but this is described for the explanation of the operation and is actually later.

In many home electric appliances such as washing machines, when the microcomputer that controls the entire system is reset, the setting of the operation mode and the like up to that point is canceled and the initial value is returned. In particular, recent washing machines are often used even when people are not watching, such as at night or at dawn. In such a case, a power failure occurs, washing is stopped halfway, and if left untouched, the product becomes inconvenient for the user. Therefore, it is necessary to prevent the reset of the system microcomputer as much as possible.

In this embodiment, at the momentary power failure level in which the power failure time is relatively short, the motor control is not stopped, and the power can be restored and the rapid acceleration can be performed. When the power failure time is long, the operation mode of the washing machine is reset. Protect the control power so that it will not be. In addition to this, finally electrically rewritable R
The operation mode of the washing machine may be stored in the OM or the like. In the case of a washing machine, since the number of revolutions of the motor greatly differs depending on the operation mode and the timing of the power failure, the switching time of the control mode needs to be changed depending on the operation mode.

In this embodiment, the control mode is switched during the power outage time. However, when the control mode is switched using the DC voltage value, the motor speed, and the like, the control can be more favorably performed.

<Embodiment 4> This embodiment utilizes the fact that the power supply of the control circuit is secured even when the inverter output is cut off, and thereby always grasps the phase of the motor and can grasp the phase of the motor. It is. The operation of this embodiment will be described with reference to FIGS.

FIG. 8 is an internal configuration diagram of the control circuit 6 shown in each of the above embodiments, and FIG. 9 is a diagram showing the phase signal θd generated by the phase updating circuit 60 shown in the internal configuration diagram of FIG. 4 shows a motor rotation speed and a motor drive signal.

In the mode of this embodiment, the inverter output is cut off at the time of a power failure, the consumption of DC power is suppressed as much as possible, the control power for the entire system is secured, and at the same time, the phase of the motor is grasped for the restart at the time of power recovery. This is the power failure standby mode to be set.

The operation of this embodiment will be described with reference to FIGS. The control circuit 6 calculates a voltage command value Vd ^* , Vq ^* from each current command value Id ^* , Iq ^* using a motor model.
d ^* , Vq ^* and the phase signal θd, the motor applied voltage Vu,
Coordinate conversion voltage output section 64 for outputting Vv and Vw, PLL
It comprises a phase update circuit 60 that performs phase matching and phase update using a technique.

The phase updating circuit 60 is a phase matching section 61 for outputting a phase updating value Δθd from the calculated value and the position information from the rotation speed calculating circuit 4 and the phase signal θd, and an output of the phase matching section 61. A phase update unit 62 updates the phase using the phase update value Δθd. Each time the position information is input, the phase matching unit 61 compares the position information with the phase signal θd, and according to the error, updates the phase update value Δ
θd is output. The phase update circuit 60 always updates the phase after power-on and outputs a phase signal θd. Here, the arithmetic expressions (Equation 1) and (Equation 2) used in the voltage operation unit 63 are shown below.

Vd = r · Id−ω _r · L · Iq (Equation 1) Vq = ω _r · L · Id + r · Iq + k _E · ω _r (Equation 2) where Vd: d-axis voltage, Id: d-axis Current, Vq: q-axis voltage, Iq: q-axis current, r: winding resistance, L: inductance, k _E : power generation constant, ω _r : rotating electrical angular frequency. The position information is detected using a position sensor using a Hall element. Therefore, the position information is information for each electrical angle of 60 degrees.

The operation of this embodiment will be described with reference to FIG.
Assuming that a power failure occurs at time t0 and a power failure is detected at time t1, the motor drive signal stops at t1, and the output of the inverter is shut off. However, since the control power supply is sufficiently secured and the control circuit 6 is operating, the phase is updated according to the rotation speed of the motor, and the phase signal θd is output. When the rotation of the motor stops at time t2, the phase update value Δθd also becomes 0, and the phase signal θd does not increase or decrease, and this state is maintained to prepare for power recovery. When the power is restored in this state, the motor can be restarted promptly because the phase of the motor is known. Further, even if the motor is rotated by any external force, the control circuit 6 is operating, so that the phase is updated, and the phase of the motor can be reliably grasped. As a result, even if a power failure occurs, the phase information of the motor can always be grasped, and a quick restart can be performed when the power is restored.

In the present embodiment, the mode is shifted to the power failure standby mode immediately after the power failure, but there is no problem if the mode is changed after passing through the instantaneous power failure continuous operation mode as in the third embodiment. Further, in this embodiment, the method of detecting the position information using the position sensor has been described. However, the position estimation information of the method of estimating the position using the motor current sensor or the like may be used.

[0058]

As described above, the use of the motor control device of the present invention makes it possible to control the DC voltage to a predetermined value by regenerating the rotational energy of the motor during a power failure. In addition, since the rotation speed of the motor is controlled even during a power failure, it is possible to quickly return to the set rotation speed when the power is restored. Further, during the power regeneration, the motor is driven in the brake mode for generating the brake torque, so that quick deceleration control can be performed. In addition, by switching the rotation speed control mode of the motor according to the power outage time at the time of power outage, appropriate control is performed according to the power outage situation.

[Brief description of the drawings]

FIG. 1 is a basic block diagram of a washing machine motor control device according to a first embodiment.

FIG. 2 is an explanatory diagram of a control method switching algorithm at the time of a power failure according to the first embodiment.

FIG. 3 is an operation explanatory diagram of the first embodiment.

FIG. 4 is a basic block diagram of a super-high-speed rotation motor control device according to a second embodiment.

FIG. 5 is an operation explanatory diagram of the second embodiment.

FIG. 6 is a basic block diagram of a washing machine motor control device according to a third embodiment.

FIG. 7 is an operation explanatory diagram of the third embodiment.

FIG. 8 is an internal circuit configuration diagram of a control circuit according to a fourth embodiment.

FIG. 9 is an operation explanatory diagram of the fourth embodiment.

[Explanation of symbols]

1. Inverter main circuit 2. Permanent magnet synchronous motor 3.
Washing tub, 4 ... rotation speed calculation circuit, 5 ... rotation speed control circuit, 6
... Control circuit, 7, 70, 700 ... Power failure operation circuit, 8, 8
0,800: power failure detection circuit, 9: rectifier circuit, 10: DC
-DC power supply, 11 magnetic bearing device, 60 phase update circuit, 61 phase matching unit, 62 phase update unit, 63 voltage calculation unit, 64 coordinate conversion voltage output unit.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Naohiko Takahashi 603, Kandamachi, Tsuchiura-shi, Ibaraki Pref. Industrial Machinery Systems Division, Hitachi, Ltd. (72) Inventor Mitsuhisa Kawamata 1-1-1 Higashitaga-cho, Hitachi City, Ibaraki F-term in Hitachi Taga Electronics Co., Ltd. (Reference) 3B155 BA21 HB09 LB02 LB17 LC15 MA05 MA06 MA08 MA09 5H576 AA12 BB06 CC01 CC05 DD07 EE01 EE09 EE22 FF05 GG02 GG04 HB02 JJ03 JJ09 JJ18 JJ24 KK06 LL24 LL39 LL41 MM13

Claims (7)

[Claims] An inverter circuit for inputting DC power, a permanent magnet synchronous motor connected to the inverter circuit,
A rotation speed control circuit that controls the rotation speed of the permanent magnet synchronous motor, and a motor driving device that obtains a control power supply from the DC power, a power failure detection circuit that detects a stop of the supply of the DC power, and when a power failure is detected. A power failure operation circuit that controls the number of revolutions of the permanent magnet synchronous motor so that the DC voltage becomes a predetermined value. In the event of a power failure, the power of the control power supply is secured using the power failure operation circuit, and the permanent magnet A motor driving device for continuously controlling the rotation speed of a synchronous motor. 2. The motor drive device according to claim 1, further comprising: a power failure operation circuit that reduces a rotation speed of the permanent magnet synchronous motor so that a DC voltage becomes a predetermined value when a power failure is detected; A motor driving device which secures electric power of the control power supply using a circuit and reduces the number of revolutions of the permanent magnet synchronous motor. 3. A rectifier circuit for converting AC power to DC power, an inverter circuit for inputting the DC power, a permanent magnet synchronous motor connected to the inverter circuit, and controlling a rotation speed of the permanent magnet synchronous motor. A rotational speed control circuit, and a magnetic bearing circuit that magnetically levitates and holds the rotor of the permanent magnet synchronous motor with the DC power, a power failure detection circuit that detects a stop of the supply of the DC power, A power failure operation circuit that reduces the rotation speed of the permanent magnet synchronous motor so that the DC voltage becomes a predetermined value at the time of power failure, while securing the power of the magnetic bearing circuit using the power failure operation circuit at the time of power failure, A motor drive device for reducing the rotation speed of a permanent magnet synchronous motor. 4. A motor driving device according to claim 1, wherein a normal operation mode for controlling the rotation speed of the motor to a predetermined value, and a DC voltage lowering the rotation speed of the motor to a predetermined value. A power failure continuation operation mode, and a power failure standby mode in which the operation of the motor is stopped to prevent the DC voltage from dropping, the length of a power supply suspension time, the number of rotations of the motor, the DC voltage value, and the like. A motor driving device for controlling the motor by selecting the control mode using at least one of the following. 5. An inverter circuit for inputting DC power, a permanent magnet synchronous motor connected to the inverter circuit,
A rotation speed control circuit that controls the rotation speed of the permanent magnet synchronous motor, a phase update circuit that updates the phase of the permanent magnet synchronous motor with the rotation of the permanent magnet synchronous motor, and a control power supply from the DC input power. A motor drive device, comprising: a power failure detection circuit that detects a stop of the supply of the DC power; in the event of a power failure, the output of the inverter circuit is shut off to secure the power of the control power supply; A motor drive device having a power failure standby mode for updating the phase of a magnet synchronous motor and preparing for power recovery. 6. A rectifier circuit for converting AC power to DC power, an inverter circuit for inputting the DC power, and a permanent magnet synchronous motor connected to the inverter circuit.
A rotation speed control circuit for controlling the rotation speed of the permanent magnet synchronous motor, and a control power supply is obtained from the DC input power,
In a washing machine that drives a washing tub with the permanent magnet synchronous motor, a power failure detection circuit that detects a power failure, and a power failure operation circuit that controls a rotation speed of the permanent magnet synchronous motor to maintain a DC voltage at a predetermined value during a power failure. A washing machine characterized in that at the time of a power failure, a DC voltage is maintained at a predetermined value by using the power failure operation circuit to secure a power source of the rotation speed control circuit, and the operation of the washing machine is maintained. 7. A washing machine according to claim 6, wherein a normal operation mode for controlling the rotation speed of said motor to a predetermined value and a power failure continuation for controlling the DC voltage to a predetermined value by reducing the rotation speed of said motor. An operation mode and a power failure standby mode in which the operation of the motor is stopped to prevent the DC voltage from lowering, using at least one of a power supply stop time, a rotation speed of the motor, and a DC voltage value. A washing machine for selecting the control mode and controlling the motor.