JP2021027758A - Electric washing machine and method of starting electric motor - Google Patents

Abstract

To reduce starting time of an electric motor and suppress the heat generation and power consumption of the electric motor.SOLUTION: A transfer mechanism 15 has an ineffective angle area where the transferable torque via the axis of the electric motor 16 is less than the maximum torque of the electric motor 16. The power circuit 55 has a first driving means 56 that energizes regardless of the position of the permanent magnets 40-47 with respect to windings 51-53 and a second drive means 57 that energizes the permanent magnets 40 to 47 with respect to the windings 51 to 53 according to the position of the permanent magnets 40 to 47. The control unit 68 is configured to control the power circuit 55 so that, when the electric motor 16 is started, the electric motor 16 is driven first within the range of the invalid angle region of the first driving means 56, and then the current is supplied to the electric motor 16 by using the second drive means 57.SELECTED DRAWING: Figure 1

Description

The present invention relates to an electric washing machine that uses an electric motor to wash clothes and the like, and a method of starting the electric motor used in the electric washing machine and the like.

Conventionally, in a motor drive control device used in this type of electric washing machine or the like, the magnitude of the lock current becomes the first predetermined value when the first predetermined time elapses from the start of the lock energization period. To control. Then, after the first predetermined time has elapsed, the magnitude of the lock current is controlled to be a second predetermined value smaller than the first predetermined value at the end of the lock energization period (see, for example, Patent Document 1). ).

FIG. 13 is a block circuit diagram of a conventional motor drive control device described in Patent Document 1. 14 (a) is a signal waveform diagram of outputs R1 to R6 of the control circuit unit 6 of the motor drive control device described in Patent Document 1, and FIG. 14 (b) is a PWM of R1 in FIG. 14 (a). It is a waveform diagram which shows the change of the time ratio (Duty) of a HIGH period and a LOW period in (Pulse Width Modulation).

As shown in FIG. 13, it includes a DC power supply 1, an inverter circuit 2, a control circuit unit 3, a motor 4, and an induced voltage detection circuit 5. The inverter circuit 2 has 6 switching elements Q1 to Q6. The control circuit unit 3 supplies on / off signals (R1 to R6) to the switching elements Q1 to Q6. The output of the inverter circuit 2 is connected to the motor 4 which is three phases (U phase, V phase, W phase). The induced voltage detection circuit 5 detects the induced electromotive force from the voltage value of each phase of the motor 4 and outputs it to the control circuit unit 3.

The control circuit unit 3 includes a predrive circuit 6, a lock energization control circuit 7, a motor drive control circuit 8, and a rotation position estimation unit 9. When the motor 4 is started, a signal is output from the lock energization control circuit 7 to the predrive circuit 6, and then a signal is output from the motor drive control circuit 8 to the predrive circuit 6. At this time, the motor drive control circuit 8 outputs a signal corresponding to the output of the induced voltage detection circuit 5 to the predrive circuit 6.

The control circuit unit 3 controls the lock energization control circuit 7 and increases the duty from 0 to D2 in the period of time T1 to T2 (first predetermined period) as shown in FIG. 14 (b). Next, the control circuit unit 3 keeps the Duty at D2 during the period of time T2 to T3 (second predetermined period). Then, the control circuit unit 3 keeps the Duty at D1 during the period from T3 to Te (third predetermined period). Here, D2> D1. By making the third predetermined period longer than the second predetermined period, the current value supplied to the motor 4 in the second predetermined period becomes smaller than the second predetermined period. As a result, at the end time Te in the lock energization process, the driven body is fixed at the rotor position where the wobbling is suppressed. In addition, heat generation due to the current supplied to the motor 4 is suppressed.

After the motor 4 is started, in the forced commutation step, a drive current is sequentially supplied to the three phases of the motor 4 by a signal from the motor drive control means 8. When the rotation speed of the rotor reaches a certain value, the process proceeds to the sensorless drive process. After that, the rotation position estimation unit 9 detects the zero cross point from the change in the induced voltage of each phase of the motor 4 and estimates the energization timing.

Japanese Unexamined Patent Publication No. 2018-093665

In the conventional configuration, in the lock energization step and the forced commutation step, the motor 4 is driven while generating torque for accelerating the moment of inertia of the load. Therefore, when the moment of inertia of the load is large as in an electric washing machine, there is a problem that it takes time to move to the sensorless drive process. As a result, it becomes difficult to realize an operation speed pattern in which the rotation is started in a short time after the rotation is stopped, and the washing performance cannot be improved.

Further, in the lock energization process and the forced commutation process, the loss due to the motor current is large, and the heat generation and the power consumption increase.

The present invention solves the above-mentioned conventional problems, and makes it possible to start the electric motor in a short time even if it has a rotating object having a large moment of inertia such as an electric washing machine. It is an object of the present invention to provide an electric washing machine that can shorten the time required to start the electric motor and realize high washing performance, and a method of starting the electric motor used in the electric washing machine or the like. Another object of the present invention is to provide an electric washing machine that suppresses heat generation of the electric motor and suppresses power consumption, and a method of starting the electric motor used in the electric washing machine or the like.

In order to solve the above-mentioned conventional problems, the electric washing machine of the present invention includes a rotating object in contact with the laundry, an electric motor having a permanent magnet and a winding, a power supply circuit for supplying an electric current to the electric motor, and a torque of the electric motor. The transmission mechanism includes a transmission mechanism for transmitting the electric current to the rotating object and a control unit for executing the washing operation, and the transmission mechanism has an invalid angle region in which the transferable torque on the shaft of the motor is smaller than the maximum torque of the motor. The power supply circuit has a first driving means for energizing regardless of the position of the permanent magnet with respect to the winding, and a second driving means for energizing according to the position of the permanent magnet with respect to the winding. , Controls the power supply circuit, supplies current to the motor using the first drive means when the motor starts, drives the motor within the range of the invalid angle region, and then supplies current to the motor using the second drive means. Is what you do.

With this configuration, even if the moment of inertia of the rotating object as a load is large, the first driving means supplies a current to the electric motor in a state where the influence of the moment of inertia of the rotating object is reduced in the range of the invalid angle region. By rotating the motor, it is possible to shift to the second driving means in a short time, and the time required to start the electric motor can be shortened. It is possible to suppress the phase variation of the current at the time when the operation of the second driving means is started. In this way, it is possible to realize an electric washing machine having high washing performance and capable of suppressing heat generation of the electric motor and suppressing power consumption.

Further, in order to solve the above-mentioned conventional problems, the method of starting the electric motor of the present invention is to rotate an electric motor, an electric motor having a permanent magnet and a winding, a power supply circuit for supplying a current to the electric motor, and a torque of the electric motor. The transmission mechanism includes a transmission mechanism that transmits to an object and a control unit that controls the power supply circuit. The transmission mechanism has an invalid angle region in which the transmittable torque on the shaft of the motor is smaller than the maximum torque of the motor, and the power supply circuit has an invalid angle region. The control unit has a first driving means for energizing regardless of the position of the permanent magnet with respect to the winding and a second driving means for energizing according to the position of the permanent magnet with respect to the winding. At startup, a first drive means is used to supply a current to the motor to drive the motor within an invalid angle region, and then a second drive means is used to supply a current to the motor.

By this method, even if the moment of inertia of the rotating object as a load is large, the first driving means supplies a current to the electric motor in a state where the influence of the moment of inertia of the rotating object is reduced in the range of the invalid angle region. By rotating the motor, it is possible to shift to the second driving means in a short time, and the time required to start the electric motor can be shortened. It is possible to suppress the phase variation of the current at the time when the operation of the second driving means is started. In this way, it is possible to realize a method of starting the electric motor of the electric washing machine, which has high washing performance and can suppress heat generation of the electric motor and suppress power consumption.

The method of starting the electric washing machine and the electric motor of the present invention can shorten the time required to start the electric motor, realize high washing performance, suppress heat generation of the electric motor, and suppress power consumption.

Block diagram of the electric washing machine according to the first embodiment of the present invention Detailed block diagram of the first driving means 56 according to the first embodiment of the present invention. Detailed block diagram of the second driving means 57 according to the first embodiment of the present invention. Detailed block diagram of the velocity phase estimation means 94 according to the first embodiment of the present invention. (A) Vector diagram of the second driving means 57 in operation according to the first embodiment of the present invention (b) Vector diagram of the second driving means 57 in operation according to the first embodiment of the present invention. (A) Schematic explanatory view of the invalid angle region of the transmission mechanism 15 according to the first embodiment of the present invention (b) Schematic explanatory view of the invalid angle region of the transmission mechanism 15 according to the first embodiment of the present invention (c) Schematic explanatory view of the invalid angle region of the transmission mechanism 15 according to the first embodiment of the present invention. Schematic explanatory view of the invalid angle region of the transmission mechanism 15 in the first embodiment Operation explanatory view of the 1st drive means 56 in Embodiment 1 of this invention An operation explanatory view of the first driving means 56 in the first embodiment of the present invention when the initial value of the actual electric angle is 0 degrees. An operation explanatory view of the first driving means 56 in the first embodiment of the present invention when the initial value of the actual electric angle is 90 degrees. An operation explanatory view of the first driving means 56 in the first embodiment of the present invention when the initial value of the actual electric angle is 180 degrees. An operation explanatory view of the first driving means 56 in the first embodiment of the present invention when the initial value of the actual electric angle is 270 degrees. Flow chart at the time of dehydration of control unit 68 in Embodiment 1 of the present invention Waveform diagram at the time of dehydration of the power supply circuit 55 according to the first embodiment of the present invention. Flow chart at the time of stirring of the control unit 68 in the first embodiment of the present invention Waveform diagram at the time of stirring of the power supply circuit 55 according to the first embodiment of the present invention. Block diagram of conventional motor drive controller (A) Output waveform diagram of the control circuit unit 6 of the conventional motor drive control device (b) PWM waveform diagram of the conventional motor drive control device

The first invention comprises a rotating object that comes into contact with laundry, an electric motor having a permanent magnet and windings, a power supply circuit that supplies an electric current to the electric motor, a transmission mechanism that transmits the torque of the electric motor to the rotating object, and a washing operation. With a control unit to execute, the transmission mechanism has an invalid angle region where the transferable torque on the motor shaft is less than the maximum torque of the motor, and the power circuit is at the position of the permanent magnet with respect to the winding. It has a first driving means for energizing regardless of the electric current and a second driving means for energizing according to the position of the permanent magnet with respect to the winding, and the control unit controls the power supply circuit and is second when the electric motor is started. This is an electric washing machine that supplies an electric current to the electric motor using the driving means 1 to drive the electric motor within an invalid angle region, and then supplies an electric current to the electric motor using the second driving means.

With this configuration, even if the moment of inertia of the rotating object as a load is large, the first driving means supplies a current to the electric motor in a state where the influence of the moment of inertia of the rotating object is reduced in the range of the invalid angle region. By rotating the motor, it is possible to shift to the second driving means in a short time, and the time required to start the electric motor can be shortened. It is possible to suppress the phase variation of the current at the time when the operation of the second driving means is started. In this way, it is possible to realize an electric washing machine having high washing performance and capable of suppressing heat generation of the electric motor and suppressing power consumption.

In the second invention, in the first invention, the second driving means is an electric washing machine that supplies the electric motor with a current based on the voltage calculated by using the voltage supplied to the electric motor and the parameters of the electric motor.

As a result, the current phase with respect to the phase of the permanent magnet after shifting to the second driving means can be controlled to an optimum value.

A third invention includes, in the first or second invention, a drum that constitutes a rotating object and stores laundry, and a water tank that includes the drum, and the first driving means is in the first phase order. The second driving means has a period for driving the electric motor by energization, and the second driving means is configured to supply a current in the second phase order opposite to the first phase order to drive the electric motor, and the transmission mechanism is , The electric washing machine is configured such that the invalid angle region with respect to the first phase order is larger than the invalid angle region with respect to the second phase order.

As a result, when the electric motor that rotates the drum having a large moment of inertia is started, the electric motor that rotates the drum in the washing operation is driven in a short time by driving the electric motor using the invalid angle region by the first driving means. Can be activated.

The fourth invention includes, in the first or second invention, a water tank in which the laundry and the washing water are housed, and a stirring blade that constitutes a rotating object and agitates the laundry and the washing water, and the transmission mechanism comprises. It is an electric washing machine that has a planetary gear and is configured to transmit the rotation decelerated by the planetary gear to the stirring blade.

As a result, the electric motor that rotates the stirring blade in the washing step and the rinsing step can be started in a short time.

According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the invalid angle region is configured such that the electric angle of the electric motor is larger than half a rotation, and the current angle of the first driving means is 1. It is an electric washing machine that is configured to be smaller than half a turn.

As a result, the phase at the time of transition from the first drive means to the second drive means due to the invalid angle region can be effectively suppressed, and unnecessary movement of the electric motor in the first drive means can be reduced. ..

A sixth invention includes a rotating object, an electric motor having a permanent magnet and a winding, a power supply circuit that supplies an electric current to the electric motor, a transmission mechanism that transmits the torque of the electric motor to the rotating object, and a control unit that controls the power supply circuit. The transmission mechanism has an invalid angle region in which the transferable torque on the shaft of the motor is smaller than the maximum torque of the motor, and the power supply circuit conducts energization regardless of the position of the permanent magnet with respect to the winding. It has one driving means and a second driving means for energizing according to the position of the permanent magnet with respect to the winding, and the control unit supplies an electric current to the electric motor by using the first driving means when the electric motor is started. This is a method of starting an electric motor that supplies an electric current to the electric motor by using a second driving means after driving the electric motor within the range of the invalid angle region.

By this method, even if the moment of inertia of the rotating object as a load is large, the first driving means supplies a current to the electric motor in a state where the influence of the moment of inertia of the rotating object is reduced in the range of the invalid angle region. By rotating the motor, it is possible to shift to the second driving means in a short time, and the time required to start the electric motor can be shortened. It is possible to suppress the phase variation of the current at the time when the operation of the second driving means is started. In this way, it is possible to realize a method of starting an electric motor such as an electric washing machine, which has high washing performance and can suppress heat generation of the electric motor and suppress power consumption.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is not limited to this embodiment.

(Embodiment 1)
FIG. 1 is a block diagram of an electric washing machine according to an embodiment of the present invention.

In FIG. 1, the electric washing machine 10 is a vertical washing machine. The rotating object 12 has a drum 13 that comes into contact with the laundry 11 and rotates in the dehydration step. Further, the rotating object 12 has a stirring blade 14 that rotates so as to stir the laundry 11 and the washing water in the washing step and the rinsing step of the washing operation.

The electric motor 16 is a synchronous motor having permanent magnets 40 to 47 and windings 50 to 52, and rotates the drum 13 and the stirring blade 14. Either the permanent magnets 40 to 47 and the windings 50 to 52 may be a stator or a rotor, and may be an inner rotor type or an outer rotor type.

The transmission mechanism 15 transmits the torque of the electric motor 16 to the drum 13 or the stirring blade 14 which is the rotating object 12. The transmission mechanism 15 is made of rubber that connects the first pulley 18 provided on the motor rotating shaft 38 of the electric motor 16, the second pulley 19 having a diameter larger than that of the first pulley 18, and the first pulley 18 and the second pulley 19. Belt 20, a planetary gear mechanism 23 connected to the second pulley 19, and a clutch 32 for switching whether the planetary gear mechanism 23 is in a coupled state or a dissociated state.

The planetary gear mechanism 23 has a sun gear 24 at the center. The sun gear 24 is provided at one end of the gear rotation shaft 21, and a second pulley 19 is provided at the other end of the gear rotation shaft 21. Further, the planetary gear mechanism 23 includes an internal gear 25 rotatably provided coaxially with the sun gear 24, three planetary gears 27, 28, 29 that mesh with both the sun gear 24 and the internal gear 25, and the planetary gear 27. It has a planetary carrier 30 that connects the centers of 28 and 29 to each other.

The internal gear 25 is connected so as to transmit torque to the drum 13. The planetary carrier 30 is connected so as to transmit torque to the stirring blade 14.

The clutch 32 switches whether the gear rotation shaft 21 and the internal gear 25 are in the coupled state or the dissociated state. In the clutch 32, the clutch spring 33 coupled to the internal gear 25 is provided on the outside of the gear rotating shaft 21, and the clutch spring 33 is entangled with the gear rotating shaft 21 so that the gear rotating shaft 21 and the internal gear 25 are entangled. And are in a combined state.

The clutch spring 33 is configured to be entwined with the gear rotation shaft 21 in the state of a crane-wound spring. As a result, the direction in which effective torque can be effectively transmitted to the internal gear 25 is limited to one direction. For example, in the present embodiment, the direction in which torque transmission is effective is the direction in which the drum 13 rotates clockwise when the electric washing machine is viewed from above during dehydration.

In a state where the gear rotation shaft 21 and the internal gear 25 are coupled by the clutch 32, the planetary gear mechanism 23 does not act, and the rotation of the gear rotation shaft 21 is directly transmitted to the internal gear 25. That is, the sun gear 24, the internal gear 25, and the planetary carrier 30 rotate together. As a result, the stirring blade 14 and the drum 13 rotate together, and the laundry 11 housed in the drum 13 also rotates together. Therefore, for example, in the dehydration step of the washing operation, the clutch 32 connects the gear rotation shaft 21 and the internal gear 25, and the drum 13 is rotated at high speed, so that a centrifugal force acts on the laundry 11 to perform the dehydration operation. Will be.

On the other hand, in the state where the gear rotation shaft 21 and the internal gear 25 are separated by the clutch 32, torque in the direction opposite to that in the above-mentioned coupled state is transmitted from the electric motor 16. In this case, the clutch spring 33 is in a state where the crane winding spring is disentangled and does not stick to the gear rotation shaft 21, so that torque is not transmitted to the internal gear 25.

In the disengaged state of the clutch 32, the planetary gear mechanism 23 operates, and the rotation of the gear rotation shaft 21 is transmitted to the planet carrier 30 via the sun gear 24 and the planetary gears 27 to 29. At this time, the rotation of the internal gear 25 is braked by the brake shoes 70 provided on the outer circumference thereof. As a result, only the stirring blade 14 rotates without rotating the drum 13, and the laundry 11 rotates together with the washing water contained in the drum 13. Therefore, for example, in the washing step or rinsing step of the washing operation, the gear rotating shaft 21 and the internal gear 25 are separated by the clutch 32, and the stirring blade 14 is rotated to stir the laundry 11 together with the washing water, and the washing operation is performed. Or a rinse operation is performed.

As described above, in the engaged state of the clutch 32 as in the dehydration step, the maximum torque required to drive the drum 13 increases accordingly according to the amount of the laundry 11. On the other hand, in the dissociated state of the clutch 32, the transmittable torque of the transmission mechanism 15, which is in the opposite direction to the dehydration step, becomes a very small value and has an invalid angle region. In particular, since the clutch spring 33 slips no matter how many rotations, the invalid angle region with respect to the reverse torque becomes an infinite rotation angle.

Further, in the engaged state of the clutch 32 as in the dehydration step, the torque required for reverse rotation of the electric motor 16 is the torque given to the stirring blade 14 in addition to the torque for slipping the clutch spring 33 described above. is there. This is equivalent to driving the stirring blade 14 during stirring, which will be described later, and there is a finite invalid angle region.

By switching between the holding state and the releasing state of the end portion of the clutch spring 33 in the state of the crane winding spring, entanglement with the gear rotating shaft 21 is prohibited, which is effective for the internal gear 25. A mechanism for blocking torque transmission from the gear rotation shaft 21 is also provided regardless of whether or not the torque transmission is possible.

The maximum torque of the electric motor 16 can be changed by setting a current limit value in the power supply circuit 55. Further, the maximum torque of the electric motor 16 can be calculated by using the maximum rated value of the torque that the electric motor can instantaneously output described in the specifications and the like. Alternatively, it can be calculated using the guaranteed value of the maximum current that does not cause demagnetization, which is described in the specifications and the like.

For example, in a three-phase permanent magnet motor, if there is a maximum value Ipeak1 or an effective value Irms1 of each line current, it can be calculated from the parameter of the induced electromotive force constant Ke [Vrms / 1000 rpm]. Alternatively, if there is a maximum value Ipeak2 or an effective value Irms2 of the current that can be passed between the other two wires when one terminal is open, it can be calculated from the parameter of the induced electromotive force constant Ke [Vrms / 1000 rpm].

The induced electromotive force is generated by changing the product of the magnetic flux of the permanent magnet and the interlinkage of the winding, and is sometimes called an induced voltage, a counter electromotive force, or back EMF (BEMF).

When the maximum torque of the electric motor is, for example, Ke = 53 [Vrms / 1000 rpm] and Ipeak2 = 4 [A], the torque constant (below (Equation 1)) and the maximum value of the current vector Ia on the dq plane (below). By the product of (Equation 2)), it becomes 2.48 [Nm] on the motor rotating shaft 38.

Further, when the electric motor has Ld ≠ Lq, a reluctance torque is generated, and a torque value considering this may be calculated to be the maximum torque.

The region where torque smaller than this can be transmitted is the invalid angle range.

In general, since the components of the transmission mechanism have elasticity, the twist angle with respect to torque naturally exists, but an invalid angle range can be realized even when a material having a particularly large non-linear component is used.

Although not shown, a large number of holes are formed in the wall surface of the cylindrical drum 13, and dehydrated water is scattered from these holes to the outside of the drum 13 during dehydration. A polypropylene water tank 35 is provided on the outside of the drum 13 to block water scattered during dehydration and prevent water from reaching the floor. It is not always necessary to provide a large number of holes in the wall surface of the drum 13. As the drum 13 without holes, dehydrated water may be drained from the upper part of the drum 13.

In the present embodiment, the electric motor 16 has an inner rotor structure, and the rotor 36 is provided inside the stator 37 so as to be rotatable around the shaft 38, but the motor 16 is not limited to the inner rotor structure. The rotor 36 may be arranged on the outside of the stator 37, or may have a surface-facing structure having a gap in the axial direction.

In the present embodiment, the rotor 36 is provided with eight permanent magnets 40 to 47. Permanent magnets 40, 42, 44, 46 have N poles on the outside, and permanent magnets 41, 43, 45, 47 have S poles on the outside, and surface magnets attached to the surface of a rotor core 48 laminated with silicon steel plates. The structure (SPM).

Here, in addition to the surface magnet structure as in the present embodiment, a permanent magnet may be embedded inside the rotor core 48. In this case, a torque called reluctance torque using the difference in inductance on the dq axis can be effectively utilized.

The windings 50, 51, and 52 of the three phases (U phase, V phase, and W phase) are provided on the stator 37. A power supply circuit 55 that supplies currents Iu, Iv, and Iw is connected to the windings 50, 51, and 52, respectively, to drive the electric motor 16. The electric motor 16 applies a force (torque) to the rotating object 12 via the transmission mechanism 15 to exert a force on the laundry 11.

In the present embodiment, the configuration of the electric motor 16 and the power supply circuit 55 may have a number of phases other than three phases, and the number of windings and permanent magnets can be freely designed. Further, although the connection of the three-phase windings is a star connection, a delta connection may also be used.

Since the electric motor 16 of the present embodiment uses a three-phase configuration, there are two phase orders, UWV, which is the first phase order, and UVW, which is the second phase order. In the UVW phase order, the electric motor 16 and the sun gear 24 rotate clockwise when viewed from above the electric washing machine. At the time of dehydration, the internal gear 25 also rotates clockwise to perform dehydration.

The power supply circuit 55 includes a first drive means 56, a second drive means 57, a switch 58, an inverter circuit 59 having a three-phase six-stone configuration, a current detection circuit 61, and a phase estimation means 94, and the current detection circuit 61. Detects the currents Iu, Iv, and Iw supplied from the inverter circuit 59 to the electric motor 16, respectively.

In the present embodiment, the current detecting means 61 is composed of three current detecting elements 63, 64, 65 called DCCT provided on each of the three phases, but in the configuration of the inverter circuit 59, switching on the low potential side is performed. A shunt resistor is provided on the inverter terminal side of the element, and the voltage generated there is converted to an analog voltage by an amplifier circuit (composed of an OP amplifier, etc.) while the switching element on the low potential side is on. It may be configured. When the motor 16 has three phases, in addition to the configuration using three shunt resistors, shunt resistors are provided only on the two phases, and the total current of the three wires is 0 for the other one phase (ΣI =). It is also possible to calculate the current value from Kirchhoff's law of 0). Further, the configuration uses only one shunt resistor, and depending on the timing of reading the voltage generated there, the three-phase current values Iu, Iv, and Iw are set in relation to the on / off timing of the switching element of each phase. It may be configured to detect separately.

The control unit 68 outputs various signals to each component at appropriate timings so that the electric washing machine can operate in order. The control unit 68 outputs the speed command signal N1ref to the first drive means 56, outputs the speed command signal N2ref to the second drive means 57, and the first drive means 56 and the second drive means 57 A signal S for switching which one is connected to the inverter circuit 59 is output to the switch 58.

The control unit 68 outputs the switching command C of the clutch 32 to the transmission mechanism 15. Further, the control unit 68 outputs a signal B for switching whether or not the brake shoes 70 (brake shoes, braking shoes, etc.) are brought into contact with the internal gear 25, and brakes the rotation of the drum 13.

Here, the brake shoe 70 uses a belt shape so that the brake can be effectively applied with a small force. Here, there is a direction of rotation in which the braking force (torque) is effective, and this is the direction of rotation during dehydration, that is, the direction clockwise when viewed from above the electric washing machine.

On the other hand, the braking force of the brake shoe 70 is small for rotation in the opposite direction. Although not shown, the gear rotation shaft 21 is provided with a bearing called a one-way clutch that rejects rotation that is counterclockwise when viewed from above the electric washing machine in order to suppress rotation in the reverse direction. As a result, during washing, the action of the brake shoe 70 becomes effective by the output signal B from the control unit 68.

Further, the control unit 68 outputs a signal F for switching the opening and closing of the water supply valve 71, which is a component necessary for the electric washing machine, and a signal D for switching the opening and closing of the drain valve 72. When the water supply valve 71 is opened by the signal F, water having pressure flows from the water pipe 73 into the water tank 35. When the drain valve 72 is opened by the signal D, the water in the water tank 35 is drained to the drain pipe 74. When the control unit 68 outputs these signals in order, the washing, dehydrating, rinsing, and other courses proceed, and the electric washing machine is established.

In FIG. 1, the components in the power supply circuit 55 and the control unit 68 are shown as separate circuit components, but this is just a block diagram, and all of these operations are performed by, for example, a one-chip microcomputer or the like. You may go. Further, the switch 58 may be configured by a relay having contacts, or may be realized by writing software such as an IF statement on a program written in the microcomputer. These make it low cost and highly reliable.

FIG. 2 shows a detailed block diagram of the first driving means 56 according to the embodiment of the present invention.

The speed converter 80 multiplies the command speed signal N1ref from the control unit 68 by a predetermined constant to convert it into an electric angular velocity ω1ref, and the integrator 81 outputs the phase θ1 of the electric angle.

In the present embodiment, the command speed signal N1ref is the mechanical speed (unit: r / min) of the rotating object 12, in addition to the mechanism reduction ratio that is effective during dehydration and stirring, as well as the number of pole pairs of the electric motor 16. It is an element of constants of 4, which is 1/2) of the number of poles, 60 [seconds / minute], and 2π [rad].

The two-phase three-phase converter 82 and the three-phase two-phase converter 83 use γδ coordinates, which are estimated dq coordinates in the power supply circuit 55. According to the input θ, the two-phase three-phase converter 82 converts the γδ coordinates to UVW with respect to the voltage according to the following (Equation 3). The three-phase two-phase converter 83 converts the current from UVW to γδ coordinates according to the following (Equation 4).

However, (Equation 3) and (Equation 4) are examples, and there are differences in various expressions due to changes in how to take zero points with respect to cos and sin, θ, differences in coefficients, and how to take positive and negative signs. .. In each case, the physical quantities of the three phases may be expressed in Cartesian coordinates, and a mathematical formula may be appropriately selected according to the design.

The output Iγ of the three-phase two-phase converter 83 is input to the subtractor 85, the error value of the γ-axis current with respect to the command value Iγref is input to the γ-axis current error amplifier 86, and V is the sum of the proportional component and the integral component.
γ is output to the two-phase three-phase converter 82.

On the other hand, the output Iδ of the three-phase two-phase converter 83 is input to the subtractor 87, the error value of the δ-axis current with respect to the command value Iδref is input to the δ-axis current error amplifier 88, and the sum of the proportional component and the integral component is used. A certain Vδ is output to the two-phase three-phase converter 82.

The PWM modulation circuit 90 receives Vu, Vv, and Vw which are the outputs of the two-phase three-phase converter 82, and compares the Duty of each of the three phases with the DC voltage VDC used by the inverter circuit 59 as 100% with the triangular wave. It is converted into an on / off digital signal, and a process of setting a dead time for switching the on period of the switching elements above and below each phase is performed to generate Q1 to Q6 which are gate signals for 6 stones.

Such a configuration in which the current vector is converted into Cartesian coordinates (γδ coordinates) to control the supply current value to the electric motor 16 is generally called vector control.

However, the configuration is not particularly limited to three phases, and a configuration having a plurality of phases can be configured, and a simple configuration is required even in a more polyphase.

FIG. 3 shows a detailed block diagram of the second driving means 57 according to the embodiment of the present invention. In FIG. 3, each component of the two-phase three-phase converter 82, the three-phase two-phase converter 83, the subtractors 85 and 87, the γ-axis current error amplifier 86, the δ-axis current error amplifier 88, and the PWM modulation circuit 90 is described. , Since it is the same as the explanation of the first driving means 56 described with reference to FIG. 2, detailed description is omitted. In FIG. 3, the value of Iγref input to the subtractor 85 is set to 0.

The speed converter 91 multiplies the command speed signal N2ref from the control unit 68 by a predetermined constant to convert it into an electric angular velocity ω2ref, and the subtractor 92 calculates a value corresponding to an error with the estimated value ω2 of the electric angular velocity. Output to amplifier 93.

The speed error amplifier 93 outputs the command value Iδref with the sum of the proportional component and the integral component as the δ-axis current value proportional to the torque.

The velocity phase estimation means 94 inputs Iγ, Iδ, and Vγ, and outputs the estimated velocity (electric angular velocity) ω2 and the estimated phase θ2. The estimated phase θ2 is calculated using the resistance values Ra and the inductance values L of the windings 50, 51, and 52, which are the parameters of the electric motor 16.

As a result, it functions as an element for supplying a current corresponding to the phase (position) of the permanent magnets 40 to 47 of the electric motor 16 to the windings 50, 51, 52 of the electric motor 16.

FIG. 4 shows a detailed block diagram of the velocity phase estimation means 94 according to the embodiment of the present invention. In FIG. 4, the velocity phase estimation means 94 includes an error voltage calculator 96, an error voltage amplifier 97, an integrator 98, and a subtractor 99.

The error voltage calculator 96 includes a converter 100 for multiplying the inductance value L, a converter 101 for multiplying the resistance value Ra, a multiplier 102 having an estimated speed ω as one input, a subtractor 103, and a subtractor 104. The subtractor 99 inputs εγ, which is the calculation result of the following (Equation 5), and the error voltage set value εγref = 0V, and outputs the result −εγ to the error voltage amplifier 97.

The error voltage amplifier 97 includes a PI-type error amplifier having a gain KP proportionalizer 108, a gain KI integrator 109, and an adder 110. The output from the error voltage amplifier 97 is time-integrated by the integrator 98 and output as the estimated phase θ. The output from the integrator 109 is output as the estimated velocity ω.

However, the error voltage computer 96 is not necessarily limited to the above calculation formula, and (Equation 6) or the like to which the time derivative term is added may be used.

Also, as in (Equation 7),

εθ = tan-1 (Vγ- (Ra ・ Iγ-ω ・ L ・ Iδ) / Vδ- (Ra ・ Iδ + ω ・ L ・ Iγ)) [rad] (7)

It may be the calculation result of the inverse trigonometric function, or the conversion function from Cartesian coordinates to polar coordinates corresponding to four quadrants. The configuration of the error voltage amplifier 97 may be a PID or fuzzy type other than the PI type.

As the inductance L in each of the above equations, the same L value can be used in the electric motor 16 having the characteristic that Ld = Lq. In an electric motor in which Ld ≠ Lq, a constant L value (= Lq) can be used in the calculation formula for estimating εθ.

FIG. 5 shows a vector diagram of the electric motor 16 in operation in the second driving means 57 of the present embodiment. FIG. 5A shows a state in which the estimated dq coordinate (γδ coordinate) is slightly behind the actual dq coordinate of the electric motor 16, and FIG. 5B shows a state in which the estimated dq coordinate (γδ coordinate) is slightly advanced. Indicates the state.

On the vector diagram, the error voltage εγ is the γ-axis component of the estimated induced electromotive force vector ω · Ψa obtained by subtracting the drop of the current flowing through Ra and ωL from the input voltage Va of the motor 16. Considering that ω ・ Ψa is always on the q-axis, the state where the estimated phase error Δθ = 0 is the state where the q-axis coincides with the δ-axis. Assuming that the state in which the γδ coordinate comes counterclockwise with respect to the dq coordinate is positive, the error voltage εγ becomes negative in the state where the estimated phase is delayed (Δθ <0) as shown in FIG. 5A. On the other hand, as shown in FIG. 5B, the error voltage εγ is positive in the state where the estimated phase is advanced (Δθ> 0).

In the case of FIG. 5A, the error voltage amplifier 97 increases the estimated speed ω to advance θ, and in the case of FIG. 5B, decreases the estimated speed ω to delay θ. In this way, the second driving means 57 drives the electric motor 16 while performing feedback control in the direction in which the error voltage εγ = 0.

FIG. 6 shows a schematic explanatory view of an invalid angle region of the transmission mechanism 15 in the present embodiment. The electric motor 16 in FIG. 1 has eight poles, but here, for the sake of simplicity, electric angle = mechanical angle 2
FIG. 6 shows a configuration diagram of a schematic mechanism corresponding to the polar configuration.

In FIG. 6, both the schematic motor shaft 115 and the schematic load shaft 116 rotate around a central shaft 117. A rotating object 12 having a large moment of inertia is connected to the model load shaft 116, while the model motor shaft 115 has only a minute moment of inertia that only the motor 16 has.

FIG. 6A shows a case where the invalid angle range (which can be said to be backlash, play, and clearance) of the transmission mechanism 15 is set to half a rotation (180 degrees) and the position of the electric motor 16 is exactly at the center thereof.

FIG. 6B shows a position where torque transmission to the model load shaft 116 is started when the model motor shaft 115 is rotated 90 degrees counterclockwise to make contact at the X portion.

FIG. 6C shows a position where torque transmission to the model load shaft 116 is started when the model motor shaft 115 is rotated 90 degrees clockwise to make contact at the Y portion.

That is, the model motor shaft 115 is in the invalid angle range without torque being transmitted at the position (including FIG. 6 (a)) between FIGS. 6 (b) and 6 (c).

Actually, since the number of poles of the electric motor 16 in FIG. 1 is eight, the play on the shaft 38 of the electric motor 16 is 1/4 times the expression in terms of the electric angle. Further, as a factor that causes the play, the play by the planetary gears 27, 28, 29 becomes large due to the deceleration element by the pulleys 18 and 19 during stirring.

Further, a mechanism for transmitting torque may be provided between the planet carrier 30 and the stirring blade 14 by engaging teeth, for example, called serrations. In that case, there is play in the tooth-to-tooth meshing portion, and the angle corresponding to that is the invalid angle range converted into an electric angle together with the play of the planetary gears 27, 28, and 29.

As a method of actually confirming the invalid angle range of the electric washing machine, the shaft 38 of the electric motor 16 is twisted by hand while the drum 13 and the stirring blade 14 are fixed so as not to rotate. If there is rattling in the range of 90 degrees (1/4 rotation = π / 2) at the time of this stirring blade, multiply this by 4, which is the logarithm of the electric motor 16, and the electric angle of 360 degrees is invalid. It can be confirmed as an angle range.

FIG. 7 shows an operation explanatory view of the first driving means 56 according to the embodiment of the present invention, in which the horizontal axis represents the electric angle of the current supplied to the electric motor 16 and the vertical axis represents the actual electric angle. In both cases, a right angle (90 degrees) is used as one unit. The case where the invalid angle range is set to a value slightly larger than half rotation (180 degrees) (assumed to be α) is shown.

In the present embodiment, the current supplied to the electric motor 16 by the first driving means 56 is set to a relatively small value, and the first is applied to the moment of inertia of the rotating object 12 and the rigid body friction load torque. It is assumed that the electric motor 16 does not rotate when the current is supplied from the drive means 56.

Of course, the first driving means 56 may supply a large current value such that the electric motor 16 rotates. However, the effect of this embodiment is that the current value of the rotating object 12 is smaller than the current value required to rotate those elements, and the current value is sufficient to rotate only the electric motor 16. In order to enable operation, the following description will be given under the above conditions.

As shown in FIG. 6A, the actual angle (initial electric angle) in the state where the electric motor 16 has an invalid angle range (play) in the non-energized state represents a position in a state where it is substantially in the center of the invalid angle range. Let the vertical axis value be the value.

Generally, when starting an electric motor using a permanent magnet, the phase at the time of starting is unknown without position detection by a Hall IC or the like, and positioning (locking) operation, forced synchronization (forced commutation, synchronous drive) , Also called synchronous operation), but all of them supply voltage or current to the motor regardless of the position of the permanent magnet. In the present embodiment, when the first driving means 56 supplies a current vector to the electric motor 16, rotational torque is generated so that the d-axis of the electric motor 16 has the same direction as the current vector. When the moment of inertia is large, the rotating object does not rotate immediately even if a current is supplied, but when it is within the invalid angle range, the d-axis has the characteristic of being in the same direction as the supplied current vector with a relatively small current. is there.

As an example in which the electric angle of the supply current is fixed, the horizontal axis value 0 in FIG. 7 will be described. The vertical axis value is also 0 on the thick solid line, and the supplied current causes point A where the actual electric angle is 0, which is the same as the supplied current, at the position shown in FIG. 6 (a). Although there are two points A in FIG. 7, the two points A are the same because the actual electrical angle difference is four right angles. This also applies to point C.

When the electric angle of the supply current is 0, when the initial electric angle is in the range of P, the d-axis is aligned with the supplied current, and the phase shifts to the point A where the permanent magnet is fixed to the winding.

On the other hand, when the initial position exists in the range of Q, the motor 16 may rotate within the invalid angle range, but it cannot move to the point A and stays at either the point B or the point C, resulting in the result. It falls within the range of R.

Here, due to the presence of α (> 0), S, which is 2R−α, is smaller than half a rotation (180 degrees). This is because the invalid angle range is made larger than the half rotation of the electric angle, and the phase variation range after the rotation of the motor occurs within the invalid angle range due to the current supply is from the half rotation k (180 degrees). Also shows that it fits in a small range.

If the phase of the supply current at the end of the operation by the first drive means 56 is not 0, it is considered that the phase variation at that time moves in parallel, and even if the current phase change from the start is increased, the half rotation k It fits in a range smaller than (180 degrees).

When the second drive means 57 calculates the estimated phase using the induced electromotive force of the electric motor 16, the speed of the electric motor 16 may increase to some extent when the operation of the second drive means 57 is started. Desirably, it is important for the phase to keep the absolute value of the estimated phase error below 90 degrees.

This relates to performing a physical quantity (mainly Iδ or the like) corresponding to torque, which is a feature of vector control, at the output of the speed error amplifier 93. If the estimated phase deviates by 90 degrees or more from the actual phase, vector control cannot be performed because the q-axis becomes negative even if current control is performed so that a positive current flows in the δ-axis. For example, in a situation where the estimated speed is lower than the command speed, even if Iδ is changed in the positive direction in order to increase the torque, the generated torque decreases or becomes negative, the motor 16 decelerates, and speed control is not established.

Therefore, in the driving period of the second driving means 57, the estimated phase needs to have an absolute value of an error of less than 90 degrees from the actual phase of the electric motor 16. Therefore, the actual phase variation of the electric motor 16 needs to be less than 180 degrees at the stage of shifting to the operation by the second drive means 57. Then, by setting the center of the phase variation as the γ axis of the estimated phase, the estimated phase error (= estimated phase-phase of the motor 16) is in the range of ± 90 degrees, and the above condition can be satisfied.

8A to 8D show operation explanatory views of the first driving means 56 in the embodiment of the present invention. The horizontal axis shows the current phase change from the start, and the vertical axis shows the actual phase of the motor 16 as the actual electric angle.

When the electric motor 16 is started (horizontal axis value 0), the current from the first driving means 56 starts supplying current from the phase value 0. The actual phase of the motor 16 at that time is generally not fixed and exists with variation in the range of 0 to 360 degrees (4 right angles). For example, when the initial value of the actual electric angle is 0 degrees, it is shown in FIG. 8A, when the initial value of the actual electric angle is 90 degrees (= 1 right angle), it is shown in FIG. 8B, and when the initial value of the actual electric angle is 180 degrees (=). FIG. 8C shows the case of (2 right angles), and FIG. 8D shows the case where the initial value of the actual electric angle is 270 degrees (= 3 right angles).

When the current phase change from the start of the electric motor 16 (horizontal axis value 0) is increased (moved to the right on the graph), a point where the current phase changes by 180 degrees (= 2 right angles) occurs. When the initial value of the actual electric angle is 0 degrees, point a (Fig. 8A), when the initial value of the actual electric angle is 90 degrees, points b and c (Fig. 8B), and when the initial value of the actual electric angle is 180 degrees, At point d (FIG. 8C) and the initial value of the actual electrical angle is 270 degrees, it is point e and point f (FIG. 8D).

At these points, reverse rotation with an electrical angle of 180 degrees occurs. Until just before that, the actual electric angle is fixed at a constant value (the d-axis stays at the most rotated position in the invalid angle range), and the generated torque increases until it reaches 90 degrees and becomes maximum. After that, the generated torque decreases, and the sign of the generated torque is reversed when it turns 180 degrees from the end of the invalid angle range.

Therefore, if the moment of inertia of the electric motor 16 is sufficiently small at this time, reverse rotation within the invalid angle range is promptly generated. In the transmission mechanism 15 in which the invalid angle range is larger than the electric angle of 180 degrees, the estimated phase error is 0, that is, the supplied current phase is in the same direction as the d-axis of the electric motor 16.

Here, by limiting the electric phase change from the start of the motor 16 (horizontal axis value 0) to a range smaller than 6 [right angle] (= one and a half rotations), in any case, the initial phase of the motor 16 is However, during the operation period of the first driving means 56, the occurrence of the reverse rotation can be reduced to once or less.

FIG. 9 is a flowchart of the control unit 68 during dehydration according to the embodiment of the present invention. Although not shown in the flowchart of FIG. 9, the elapsed time t increases with the passage of time, and after passing through the first driving process, step 122, and the second driving process, step 123, the dehydration is completed in step 125. To reach. Dehydration is started in step 120, and the elapsed time t is reset in step 121 (t = 0 [s]).

First, step 122, which is the first driving process, will be described.

In step 130, the control unit 68 outputs a signal S for selecting the first drive means 56 to the switch 58.

At the time of dehydration, the deceleration function by the planetary gears 27, 28, 29 does not work, and the value of N1ref is shown as the speed at which the drum 13 rotates at the same speed as the stirring blade 14. In step 131, the speed command signal N1ref = 0 [r / min] is set to a stopped state (generally called positioning or locking). In the present embodiment, the current is then supplied to the electric motor 16 from the first drive means 56.

In step 133, the time waiting for t> T1a is performed. For example, T1a = 0.2 [s]. In step 135, when the T1a time has elapsed, N1ref = −0.13 [r / min]. In the present embodiment, the UVW phase order, which is clockwise when viewed from above the electric washing machine, is positive, so a negative N1ref means operation in the UWV phase order, which is counterclockwise.

In step 137, the time waiting control of t> T1b is performed. For example, T1b = 1.2 [s]. The rotation in the reverse direction (UWV phase order) by the first driving means 56 is T1b-T1a = 1 [s].

In the present embodiment, the reduction ratio of the pulleys 18 and 19 is about 3.8, and the electric motor 16 has 8 poles. Therefore, the phase change (rotation) of the supply current is 1 [s] rotation of the drum 13. Therefore, the electric angle becomes 2 rotations (720 degrees).

However, since torque cannot be transmitted to the clutch spring 33 during this period, the drum 13 does not rotate and only the stirring blade 14 rotates. Since the planetary gears 27, 28, and 29 are engaged, the angle of reverse rotation of the stirring blade 14 is about 8 degrees at the maximum. Actually, due to the phase of the electric motor 16 at that time and the presence of rattling in the planetary gears 27, 28, 29, etc., the invalid angle range also acts in the opposite direction of the stirring blade 14, and the stirring blade 14 is 8 degrees. The stirring blade rotates in the reverse direction at a smaller angle.

Here, some torque is required to rotate the stirring blade 14 in the reverse direction. In the present embodiment, the current value for operating the first driving means 56 during the period from T1a to T1b is set to Ia = 2 [A]. This is the torque that enables the rotation of the drum 13 after T1b.

In step 139, the first driving means 56 is stopped again with N1ref = 0 [r / min]. Then, after performing the time waiting control of t> T1c in step 141, N1ref = N1ref + ΔN [r / min] is set in step 144. In step 146, ΔN is multiplied by the acceleration [r / min / s] while the time wait control of t> T1d is performed.

When N1ref = 35 [r / min] at the time of t = T1d is reached, the process proceeds to the second driving means process (step 123). By the first driving means 56, the electric angle is 26.6 [rotation], and the acceleration operation is performed by forced synchronization.

In particular, in the present embodiment, torque transmission can be performed in only one direction (clockwise when viewed from above the electric washing machine) caused by the configuration of the clutch spring 33 in the clutch 32, and torque is applied to the drum 13 in the reverse direction. Is not transmitted. Utilizing this, by setting N1ref to a negative value in step 135, positioning and forced synchronization can be performed under the condition that the torque required by the electric motor 16 is small.

Next, step 123, which is the second driving process, will be described.

In step 149, the control unit 68 outputs a signal S for selecting the second drive means 57 to the switch 58. In step 150, the initial command speed of the second driving means 57 is set to N2ref = 35 [r / min]. In the present embodiment, in step 151, which is equal to the command speed of the first driving means 56 in T1d and is set to a continuous value, N2ref = Min (N2ref + ΔN, 740) [r / min.
]. Here, the function "Min ()" outputs the minimum absolute value of a plurality of values in parentheses.

In step 153, while the time wait control of t> T2 is performed, ΔN is multiplied by the acceleration [r / min / s] of the drum 13. As a result, the command speed is increased and the speed is controlled. After reaching N2ref = 740 [r / min], a constant value of 740 [r / min] is set to the command speed.

FIG. 10 shows a waveform diagram of the power supply circuit according to the embodiment of the present invention when dehydrated. The upper figure of FIG. 10 shows the electric angular velocity, and the lower figure of FIG. 10 shows the current. This is a period in which T1a to T1b output the reverse phase order, and at T1d, the operation by the first driving means 56 shifts to the operation by the second driving means 57.

After T1d, velocity control becomes effective, and the required current Ia changes depending on factors such as friction loss and moment of inertia of the rotating object 12. In the lower figure of FIG. 10, as shown by the solid line, the alternate long and short dash line, and the broken line, the current value changes so as to establish the speed control. Although the current values of T1a to T1d are constant, the set values of Iγref and Iδref may be changed with time.

FIG. 11 shows a flowchart of the control unit 68 during stirring according to the embodiment of the present invention. Similar to the time of dehydration, although not shown in the flowchart of FIG. 11, the elapsed time t increases with the passage of time, and goes through the first driving process, step 158, and the second driving process, step 159. The process proceeds to step 161 at which stirring is completed.

Stirring is started in step 156, and the elapsed time t is reset in step 157 (t = 0 [s]).

First, step 158, which is the first driving process, will be described.

In step 163, the control unit 68 outputs a signal S for selecting the first drive means 56 to the switch 58, and in step 164, sets the command speed of the first drive means 56 to N1ref = 4.39 [r. / Min]. In the present embodiment, the deceleration function by the planetary gears 27, 28, 29 works during stirring, and N1ref is shown as the rotation speed of the stirring blade 14. At the time of stirring, all N1refs are set to positive values, and the UVW phase order is clockwise when viewed from above the electric washing machine.

Therefore, in order to perform stirring such that the left and right rotations are alternately performed, after the operation of FIG. 11 has completed the flow chart, the operation flowchart of FIG. 11 is again rotated in the opposite direction with the symbols for all speeds reversed. Operate counterclockwise when viewed from above the electric washing machine. By performing this a plurality of times, it is possible to perform operations such as washing and rinsing, including forward rotation and reverse rotation.

In step 166, the time wait control of t> T1 is performed. T1 is, for example, 0.1 [s]. By operating at N1ref = 4.39 [r / min] for 0.1 [s] time, rotation is performed at an electric angle of 240 degrees.

Next, step 159, which is the second driving process, will be described.

In step 169, the control unit 68 outputs a signal S for selecting the second drive means 57 to the switch 58. In step 170, the initial command speed of the second drive means 57 is set. In the present embodiment, N2ref = N1ref [r / min], and the value of the immediately preceding N1ref is continued.

In step 171, N2ref = Min (N2ref + ΔN, 115) [r / min]. Here, the function "Min ()" outputs the minimum absolute value of a plurality of values in parentheses.

In step 173, while the time waiting control of t> T2 is performed, ΔN is multiplied by the acceleration [r / min / s] of the stirring blade 14. As a result, the command speed is increased and the speed is controlled. After reaching N2ref = 115 [r / min], a constant value of 115 [r / min] is set as the command speed.

At the time of stirring, the first driving means 56 does not perform a positioning operation such that the command speed N1ref = 0, and there is no operation of increasing the speed from 0 with time. It has a simple structure.

It is important to perform the operation at the time of stirring in a short time (1 to 2 seconds) from the start to the stop of the stirring blade 14 in order to ensure the performance of easy washing and rinsing. Therefore, it is necessary to perform the transition from the first driving means 56 to the second driving means 57 in the shortest possible time. In this embodiment, the positioning operation (N1ref = 0) is omitted, the forced synchronization period is set to about 0.1 [s], and the speed during that period is set to a constant value (equivalent to an electric angle of 240 degrees), so that the invalid angle is set. The rotational movement of the electric motor 16 within the range can be performed quickly. As a result, the phase variation of the electric motor 16 at the time of transition from the first drive means 56 to the second drive means 57 can be suppressed within the electric angle of 180 degrees. Further, during stirring, the moment of inertia converted to the shaft 38 of the electric motor 16 becomes smaller than that during dehydration, so that operation without step-out is possible.

FIG. 12 shows a waveform diagram of the power supply circuit during stirring according to the embodiment of the present invention. The upper figure of FIG. 12 shows the electric angular velocity, and the lower figure of FIG. 12 shows the current.

Although the current value is constant during the period before T1, the set values of Iγref and Iδref may be changed with time.

At time T1, the first drive means 56 shifts to the second drive means 57. In T1, the electric angular velocity has the characteristics shown by the solid line, but as shown by the broken line, the electric angular velocity may be started from 0. Optimal design can be performed while checking the movement of the stirring blade 14 and the movement of the electric motor 16.

After T1, the velocity control becomes effective, and the required current Ia changes depending on factors such as friction loss and moment of inertia of the rotating object 12. In the lower figure of FIG. 12, as shown by the solid line, the alternate long and short dash line, and the broken line, the current value changes so as to establish the speed control.

Further, N1ref may be in the opposite rotation direction to N2ref during stirring as in dehydration. Under the condition that the invalid angle range is finite in both rotation directions, the first driving means 56 operates in the opposite direction to provide a margin for taking back from the end of the invalid angle range in the positive direction. Is possible. Moving from that state to the second driving means 57 in the positive direction, or continuing the operation of the first driving means 56 in the positive direction in that state and changing the current and frequency settings, etc. The configuration may be effective for the operation.

In the present embodiment, the first driving means 56 performs current control using subtractors 85 and 87, a γ-axis current error amplifier 86, a delta-axis current error amplifier 88, and the like, but is particularly suitable for current control. It is not limited. V-voltage control of Vγ and Vδ, which can utilize the damped vibration action of the resistors Ra of the windings 50, 51, and 52 of the electric motor 16, may be used, and a configuration with a built-in dead time compensation or impedance compensation, or a predetermined configuration The configuration may be such that PWM is performed by Duty. With respect to the electric phase 0 to 360 degrees at the time when the actual motor 16 is started.
If either the supplied voltage or the current is measured with a difference of about 10% or less, it is effective as an element of the first driving means 56.

As described above, according to the present embodiment, the rotating object in contact with the laundry, the electric motor having a permanent magnet and the winding, the power supply circuit for supplying an electric current to the electric motor, and the torque of the electric motor are transmitted to the rotating object. The transmission mechanism includes a transmission mechanism and a control unit that executes a washing operation, the transmission mechanism has an invalid angle region in which the transmissible torque on the shaft of the motor is smaller than the maximum torque of the motor, and the power supply circuit is wound. It has a first driving means for energizing regardless of the position of the permanent magnet with respect to the wire and a second driving means for energizing according to the position of the permanent magnet with respect to the winding, and the control unit controls the power supply circuit. Then, when the electric motor is started, the electric current is supplied to the electric motor by using the first driving means, the electric motor is driven in the range of the invalid angle region, and then the electric current is supplied to the electric motor by using the second driving means. is there.

With this configuration, even if the moment of inertia of the rotating object as a load is large, the first driving means supplies a current to the electric motor in a state where the influence of the moment of inertia of the rotating object is reduced in the range of the invalid angle region. By rotating the motor, it is possible to shift to the second driving means in a short time, and the time required to start the electric motor can be shortened. It is possible to suppress the phase variation of the current at the time when the operation of the second driving means is started. In this way, it is possible to realize an electric washing machine having high washing performance and capable of suppressing heat generation of the electric motor and suppressing power consumption.

Further, the second driving means is an electric washing machine that supplies the electric motor with a current based on the phase calculated by using the voltage supplied to the electric motor and the parameters of the electric motor.

As a result, the current phase with respect to the phase of the permanent magnet after shifting to the second driving means can be controlled to an optimum value.

Further, it includes a drum that constitutes a rotating object and stores laundry, and a water tank that contains the drum, and the first driving means has a period for driving the electric motor by energizing in the first phase order, and the second The driving means is configured to supply a current in a second phase order that is opposite to the first phase order to drive the electric motor, and the transmission mechanism has an invalid angle region with respect to the first phase order. It is an electric washing machine configured to be larger than the invalid angle region with respect to the phase order of 2.

As a result, when the electric motor that rotates the drum having a large moment of inertia is started, the electric motor that rotates the drum in the washing operation is driven in a short time by driving the electric motor using the invalid angle region by the first driving means. Can be activated.

In addition, it is provided with a water tank in which laundry and washing water are housed, and a stirring blade that constitutes a rotating object and stirs the laundry and washing water, and the transmission mechanism has a planetary gear and rotates decelerated by the planetary gear. It is an electric washing machine configured to transmit to the stirring blade.

As a result, the electric motor that rotates the stirring blade in the washing step and the rinsing step can be started in a short time.

Further, the invalid angle region is an electric washing machine configured so that the electric angle of the electric motor is larger than half a rotation and the current angle of the first driving means is smaller than one and a half rotations.

As a result, the phase at the time of transition from the first drive means to the second drive means due to the invalid angle region can be effectively suppressed, and unnecessary movement of the electric motor in the first drive means can be reduced. ..

Further, according to the present embodiment, a rotating object, an electric motor having a permanent magnet and a winding, a power supply circuit for supplying an electric current to the electric motor, a transmission mechanism for transmitting the torque of the electric motor to the rotating object, and a power supply circuit are controlled. The transmission mechanism has an invalid angle region where the transmittable torque on the motor shaft is less than the maximum torque of the motor, and the power supply circuit is independent of the position of the permanent magnet with respect to the winding. It has a first driving means for energizing and a second driving means for energizing according to the position of the permanent magnet with respect to the winding, and the control unit uses the first driving means when the electric motor is started. This is a method of starting an electric motor that supplies an electric current to the electric motor by using a second driving means after driving the electric motor within an invalid angle region.

By this method, even if the moment of inertia of the rotating object as a load is large, the first driving means supplies a current to the electric motor in a state where the influence of the moment of inertia of the rotating object is reduced in the range of the invalid angle region. By rotating the motor, it is possible to shift to the second driving means in a short time, and the time required to start the electric motor can be shortened. It is possible to suppress the phase variation of the current at the time when the operation of the second driving means is started. In this way, it is possible to realize a method of starting an electric motor such as an electric washing machine, which has high washing performance and can suppress heat generation of the electric motor and suppress power consumption.

As described above, in the method of starting the electric washing machine and the electric motor according to the present invention, the electric motor is rotated in the invalid angle region by the first driving means while using a rotating object having a large moment of inertia. Since it is possible to stabilize the operation of the driving means of the above, high performance can be obtained in an electric washing machine or the like in which repeated activation for a short time is effective. For example, a configuration with stirring blades such as pulsator type and agitator type, a vertical electric washing machine with a drum whose rotation axis is tilted vertically and vertically, and a rotation axis horizontally and tilted with respect to horizontal. It can also be applied to applications such as holding drums. It can also be applied to various commercial and household devices.

10 Electric washing machine 11 Washing 12 Rotating object 13 Drum 14 Stirring blade 15 Transmission mechanism 16 Electric motor 23 Planetary gear mechanism 27, 28, 29 Planetary gear 35 Water tank 40, 41, 42, 43, 44, 45, 46, 47 Permanent magnet 50, 51, 52 Winding 55 Power supply circuit 56 First drive means 57 Second drive means 68 Control unit

Claims (6)

A rotating object that comes into contact with the laundry, an electric motor having a permanent magnet and a winding, a power supply circuit that supplies an electric current to the electric motor, a transmission mechanism that transmits the torque of the electric motor to the rotating object, and a control for executing the washing operation. With a part,
The transmission mechanism has an invalid angle region in which the torque that can be transmitted on the shaft of the motor is smaller than the maximum torque of the motor.
The power supply circuit includes a first driving means for energizing the winding regardless of the position of the permanent magnet, and a second driving means for energizing the winding according to the position of the permanent magnet. And
The control unit controls the power supply circuit, supplies a current to the electric motor by using the first driving means at the time of starting the electric motor, drives the electric motor within the range of the invalid angle region, and then the second. To supply an electric current to the motor using the driving means of
Electric washing machine. The second driving means supplies the electric motor with a voltage based on the voltage supplied to the electric motor and a current calculated based on the parameters of the electric motor.
The electric washing machine according to claim 1. A drum that constitutes the rotating object and stores the laundry, and a water tank that contains the drum are provided.
The first driving means has a period for driving the electric motor by energization in the first phase order.
The second driving means is configured to drive the electric motor by supplying a current in a second phase order that is opposite to that of the first phase order.
The transmission mechanism is configured such that the invalid angle region with respect to the first phase order is larger than the invalid angle region with respect to the second phase order.
The electric washing machine according to claim 1 or 2. It is provided with a water tank in which laundry and washing water are housed, and a stirring blade that constitutes the rotating object and stirs the laundry and the washing water.
The transmission mechanism has a planetary gear and is configured to transmit the rotation decelerated by the planetary gear to the stirring blade.
The electric washing machine according to claim 1 or 2. The invalid angle region is configured such that the electric angle of the electric motor is larger than half a rotation and the current angle of the first driving means is smaller than one and a half rotations.
The electric washing machine according to any one of claims 1 to 4. It includes a rotating object, an electric motor having a permanent magnet and a winding, a power supply circuit that supplies an electric current to the electric motor, a transmission mechanism that transmits the torque of the electric motor to the rotating object, and a control unit that controls the power supply circuit. ,
The transmission mechanism has an invalid angle region in which the torque that can be transmitted on the shaft of the motor is smaller than the maximum torque of the motor.
The power supply circuit includes a first driving means for energizing the winding regardless of the position of the permanent magnet, and a second driving means for energizing the winding according to the position of the permanent magnet. And
When the electric motor is started, the control unit supplies a current to the electric motor by using the first driving means to drive the electric motor within the range of the invalid angle region, and then uses the second driving means to drive the electric motor. A method of starting an electric motor that supplies electric current to the electric motor.