KR101197900B1 - Motor driver for washing machine - Google Patents

Abstract

By providing the motor drive device of the washing machine which can generate the boosting voltage required reliably when rotating a motor at high speed,
The control circuit 42B inputs the full-wave rectifying circuit 45 between the zero cross timings of the voltage waveforms of the AC power supply by the IGBT48 in accordance with the change in the rotational speed of the drum motor 5 which is a control parameter in the case of performing dehydration operation. The number of times of shorting between the terminals is changed, and the DC power supply voltage output from the full-wave rectifier circuit 45 is boosted higher by effectively using the electron energy stored in the reactor 44.

Description

Motor drive device of washing machine {MOTOR DRIVER FOR WASHING MACHINE}

The present invention relates to a motor driving apparatus of a washing machine having a reactor between an AC power supply and a rectifier circuit.

For example, Patent Document 1 discloses a configuration as described below for a laundry dryer having a configuration in which a DC power supply of a first inverter circuit for driving a laundry dewatering motor and a second inverter circuit for driving a compressor motor of a heat pump are shared. have.

That is, in the dehydration drying operation, the DC voltage is lowered so that the laundry dehydration motor and the compressor motor rotate at the same time at high speed, and the drying time is lengthened by the dehydration rotation speed and the dehydration rate being lowered. In addition, when the AC power supply voltage decreases, the AC current increases, so that there is a problem that the high frequency of the power supply increases or that the heat generation of power components such as a reactor (inductive reactor, coil) or a power diode increases.

Therefore, in Patent Document 1, a reactor, a rectifier circuit for generating a DC power source, and a short circuit means for shorting the AC input terminal of the rectifier circuit are connected between the AC power source and the inverter circuit, and the predetermined voltage is determined from the zero voltage of the AC power source voltage. During the time, the AC input terminals are shorted so that current flows through the reactor and the DC power bus voltage is controlled.

However, in the configuration of Patent Document 1, since the number of short-circuits by the short-circuit means is only once in a half cycle of a commercial AC power supply, a sufficient boosting effect cannot actually be obtained.

For example, when the motor is rotated at high speed in dewatering operation, a high power supply voltage that overcomes the high induced voltage generated in the winding of the motor is required. As in Patent Document 1, even if the time for short-circuit is controlled once, the voltage cannot be increased beyond the amount of electron energy accumulated in the reactor within the time, so that the voltage-up effect has a limit.

Japanese Unexamined Patent Publication No. 2008-183087

This invention is made | formed in view of the said situation, The objective is to provide the motor drive device of the washing machine which can generate | occur | produce the boost voltage required in the case of rotating a motor at high speed more reliably.

Motor driving device of the washing machine of the present invention to achieve the above object

Rectifier circuit connected to the AC power supply through the reactor,

Short-circuit means for shorting between input terminals of said rectifier circuit,

An inverter circuit connected to an output side of the rectifier circuit to drive a motor that converts DC power into AC power and generates a rotational driving force for at least dehydration operation;

And a short circuit control means for changing the number of times of shorting between the input terminals between zero cross timings of the voltage waveform of the AC power supply by the short circuit means in accordance with a change of a control parameter in the case of performing the dehydration operation. do.

In other words, if the number of times of shorting between the input terminals of the rectifier circuit is changed between the zero cross timings, it is possible to effectively boost the DC power supply voltage output from the rectifier circuit using the electron energy stored in the reactor effectively. Therefore, it is possible to increase the rotation speed of the motor higher in the dewatering operation and to improve the dewatering effect.

According to the motor driving apparatus of the washing machine of the present invention, the efficiency of the dewatering operation can be improved by increasing the rotational speed of the motor, so that energy consumption can be reduced by suppressing the current consumption.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a first embodiment, schematically showing a drive control system of each motor of a drum, a fan, and a compressor in a laundry dryer;
2 is a longitudinal side view showing the configuration of a drum type laundry dryer;
3 is a view showing a configuration of a heat pump;
4 is a flowchart schematically illustrating a series of process operations of a laundry dryer;
5 is a flowchart showing a process in which a control circuit controls the driving power supply voltage;
6 is a time chart showing the process from washing to dehydration;
7 is a waveform diagram showing a state in which a power supply voltage is changed;
FIG. 8A is a diagram showing the maximum rotational speed of a motor that can be reached when the DC power supply voltage is changed; and (b) is an inverter when the rotational speed of the motor is constant at 1200 rpm by changing the voltage in the same manner. A diagram showing the power consumption of the circuit,
9 corresponds to FIG. 6 showing a second embodiment;
10 is a flowchart showing details of a process corresponding to step S14,
11 is a view corresponding to FIG. 10 showing a third embodiment;
12 corresponds to FIG. 11 showing a fourth embodiment;
13 is a view corresponding to FIG. 11 showing a fifth embodiment;
14 corresponds to FIG. 10 showing a sixth embodiment;
15 is equivalent to FIG. 7,
16 corresponds to FIG. 14 showing a seventh embodiment;
17 corresponds to FIG. 14 showing an eighth embodiment, and
18 is a diagram corresponding to FIG. 14 showing a ninth embodiment.

(Embodiment 1)

Hereinafter, the first embodiment will be described with reference to FIGS. 1 to 8. 2 is a longitudinal side view illustrating the configuration of a drum type laundry dryer. The outer box 1 forms a hollow shape having a front plate, a rear plate, a left plate, a right plate, a bottom plate and a ceiling plate, and the front plate of the outer box 1 is formed with a through-hole doorway 2 formed therein. have.

The door 3 is mounted on the front plate of the outer box 1. The door (3) is a user can operate between the closed state and the open state from the front, the door (2) is closed in the closed state of the door 3, the door (2) in the open state of the door (3) Open.

The drip tray 4 is fixed inside the outer box 1. The drip tank 4 forms a cylindrical shape in which the rear surface is closed, and is disposed in an inclined state in which the axial center line CL descends from the front to the rear. The drip tray 4 is a front face opening, and in the closed state of the door 3, the door 3 closes the front surface of the drip tank 4 in an airtight state.

The drum motor 5 is fixed to the rear plate of the drip tank 4 by being located outside the drip tank 4. The drum motor 5 is made of a DC brushless motor capable of speed control, and the rotating shaft 6 of the drum motor 5 protrudes inside the drip tank 4.

The rotary shaft 6 is disposed overlapping with the axial center line CL of the drip tank 4, and the drum 7 is fixed to the rotary shaft 6 by being located inside the drip tank 4. The drum 7 has a cylindrical shape with a rear surface closed, and rotates integrally with the rotation shaft 6 in the operating state of the drum motor 5.

The front face of the drum 7 faces the doorway 2 from the rear through the front face of the drip tank 4, and the door 7 is opened from the front in the open state of the door 3 inside the drum 7. ) And laundry through the front face of the drip tank 4 and the front face of the drum 7.

The drum 7 is provided with a plurality of through holes 8, and the internal space of the drum 7 is connected to the internal space of the drip tray 4 via each of the plurality of through holes 8. A plurality of baffles 9 are fixed to the drum 7.

Each of these plural baffles 9 moves in the circumferential direction about the axial center line CL as the drum 7 rotates, and the laundry in the drum 7 is attached to each of the plural baffles 9. It is stirred by moving in the circumferential direction while falling and falling by gravity.

The water supply valve 10 is fixed inside the outer box 1. The water supply valve 10 has an inlet and an outlet, and the inlet of the water supply valve 10 is connected to the tap. The water supply valve 10 uses an electronic device (not shown) as a driving source, and the outlet of the water supply valve 10 can switch the open state and the closed state according to the on / off of the electronic device.

The outlet of the water supply valve 10 is connected to the water supply case 12. In the open state of the water supply valve 10, tap water is injected into the water supply case 12 through the water supply valve 10, and the water supply valve 10 In the closed state, the tap water is not injected into the pouring case 12. The water pouring case 12 is located at a position higher than the drip tray 4 inside the outer box 1 and is fixed, and has a cylindrical water pouring port 13.

The water inlet 13 is inserted into the drip tray 4, and the tap water injected into the water casing 12 from the water supply valve 10 is injected into the drip tank 4 from the water spout 13. do.

The upper end of the drain pipe 14 is connected to the drip tank 4 at the lowest part, and the drain pipe 14 is interposed with the drain valve 15. The drain valve 15 uses a drain valve motor (not shown) as a driving source, and can switch the open state and the closed state in accordance with the winding-up and rewinding of the drain valve motor.

In the closed state of the drain valve 15, tap water injected into the drip tank 4 from the water inlet 13 is stored in the drip tank 4, and in the open state of the drain valve 15, Tap water is discharged to the outside of the drip tray 4 through the drain pipe 14.

The main duct 17 is fixed to the bottom plate of the outer box 1 under the drip tray 4. The main duct 17 has a cylindrical shape directed in the front-rear direction, and the lower end of the front duct 18 is connected to the front end of the main duct 17.

The front duct 18 has a cylindrical shape directed in the vertical direction, and the upper end of the front duct 18 is connected to the inner space of the drip tray 4 at the front end of the drip tank 4. have. The fan casing 19 is fixed to the rear end of the main duct 17.

The fan casing 19 has a through-hole inlet 20 and a tubular exhaust port 21. The inner space of the fan casing 19 is an inner space of the main duct 17 through the inlet 20. Is connected to.

The fan motor 22 is fixed to the fan casing 19 outside the fan casing 19. The fan motor 22 has a rotating shaft 23 projecting inside the fan casing 19, and the fan 24 is fixed to the rotating shaft 23 by being located inside the fan casing 19.

The fan 24 is a centrifugal type which sucks air from the axial direction and discharges it in the radial direction, and the inlet 20 of the fan casing 19 is connected to the fan 24 from the axial direction of the fan 24. On the other hand, the exhaust port 21 of the fan casing 19 opposes the fan 24 from the radial direction of the fan 24.

The lower end of the rear duct 25 is connected to the exhaust port 21 of the fan casing 19. The rear duct 25 forms a tubular shape directed in the vertical direction, and the upper end of the rear duct 25 is connected to the internal space of the drip tray 4 at the rear end of the drip tank 4.

These rear ducts 25, fan casings 19, main ducts 17, front ducts 18 and drip trays 4 are annular circulation ducts having the inner space of the drip tank 4 as starting and ending points ( 26, and when the fan motor 22 is operated in the closed state of the door 3, the air in the drip tank 4 is rotated in a predetermined direction by the fan 24 so that the front duct 18 ) Is sucked into the fan casing 19 from within the main duct 17, and returns to the drip tray 4 from within the fan casing 19 through the rear duct 25.

A compressor (compressor) 27 is fixed inside the outer box 1. The compressor 27 is disposed outside the circulation duct 26 and has a discharge port for discharging the refrigerant and a suction port for sucking the refrigerant. The compressor 27 uses a compressor motor (hereinafter referred to as a compressor motor) 28 (see FIG. 1 to be described later) as a drive source, and the compressor motor 28 is constituted by a DC brushless motor capable of speed control.

A condenser (condenser) 29 is fixed inside the main duct 17. The condenser 29 is configured to heat air and fix each of the plurality of heating fins 31 in a plate shape to the outer circumferential surface of one refrigerant pipe 30 that is bent in a meandering shape in a contact state.

The refrigerant pipe 30 of the condenser 29 is connected to the discharge port of the compressor 27. In the operating state of the compressor motor 28, the refrigerant discharged from the discharge port of the compressor 27 is the refrigerant pipe of the condenser 29. Enter 30.

Inside the outer box 1, a capillary tube (decompressor) 32 is fixed as shown in FIG. The capillary tube 32 is connected to the refrigerant pipe 30 of the condenser 29 and is disposed outside the circulation duct 26.

The capillary tube 32 narrows the flow of the coolant on the downstream side of the condenser 29 and is composed of one pipe.

An evaporator 33 is fixed inside the main duct 17. The evaporator 33 cools the air, and is disposed on the upstream side of the air flow rather than the condenser 29.

1 schematically shows the drive control system of the drum motor 5, the fan motor 22 and the comp motor 28. The inverter circuit 34 is constituted by connecting three IGBTs (switching elements) 35a to 35f by three-phase bridges, and between the collector-emitters of each IGBT 35a to 35f, a flywheel diode ( flywheel diodes 36a to 36f are connected. Each phase output terminal of the inverter circuit 34 is connected to each phase winding of the drum motor 5.

The emitters of the IGBTs 35d, 35e, and 35f on the lower arm side are connected to ground through shunt resistors 37u, 37v, and 37w. The common connection point of the emitters of the IGBTs 35d, 35e, and 35f and the shunt resistors 37u, 37v, and 37w is connected to the input terminal of one control circuit (microprocessor, microcomputer) 42A.

Although not shown inside the control circuit 42A, it includes an operational amplifier (op amp) and the like, and amplifies the terminal voltage of the shunt resistors 37u to 37w by the level shift circuit, and the output range of the amplified signal is positive. The bias is applied so as to enter (for example, 0 to +3.3 V). In addition, the control circuit 42A has a function of performing overcurrent detection to prevent breakage of the circuit when the lower arm is short-circuited on the inverter circuit 34.

Inverter circuits 38 and shunt resistors 39 (u, v, w), which are configured similarly to the fan motor 22, are disposed, and the inverter circuits 40 and the comparators 28 are similarly provided. Shunt resistors 41 (u, v, w) are arranged.

Control of the inverter circuits 38 and 40 is carried out by the other control circuit 42B (microprocessor, microcomputer), short circuit control means, and the control circuits 42A and 42B are capable of bidirectional communication by serial communication. It is done.

The driving power supply circuit 43 is connected to the input side of the inverter circuits 34, 38, 40. The driving power supply circuit 43 is connected to one end side via a reactor (inductive reactor) 44 with respect to a 100 V AC power supply, and is a full-wave rectifier composed of a diode bridge. The circuit 45 and two capacitors 46a and 46b connected in series to the output side of the full-wave rectifying circuit 45 are provided.

Common connection points of the capacitors 46a and 46b are connected to one of the input terminals of the full-wave rectifier circuit 45. The driving power supply circuit 43 double-waves full-wave rectification of an AC power supply of 100 V when the boost operation using the reactor 44, which will be described later, is performed, and a DC voltage of about 280 V is applied to the inverter circuit 34 or the like. Supply.

The other full-wave rectifier circuit 47 (short circuit means) comprised similarly to a diode bridge is connected to the input terminal of the full-wave rectifier circuit 45, and IGBT48 (short circuit) is provided between the output terminals of the full-wave rectifier circuit 47. Means) are connected. On-off control of the IGBT48 is performed by the control circuit 42B.

The series circuit of the resistors 49a and 49b and the series circuit of the resistors 50a and 50b are connected between the input terminals of the inverter circuits 34 and 38, respectively, and each common connection point is input to the control circuits 42A and 42B. It is connected to the terminal.

The control circuits 42A and 42B detect the drive power supply voltages input to the inverter circuits 34 and 38 by referring to the voltages of the respective common connection points.

In addition, in order to detect the rotor position with respect to the drum motor 5, for example, position sensors 51 (u, v, w) made of, for example, wheel ICs are disposed, and the position sensors 51 output. The sensor signal is provided to the control circuit 42A.

In addition, a current sensor 52 made of, for example, a current transformer CT is inserted between the AC power supply and the reactor 44, and a sensor signal output from the current sensor 52 is provided to the control circuit 42B. have.

The control circuits 42A and 42B detect currents flowing in the windings of the phases of the drum motor 5, the fan motor 22, and the comp motor 28, and based on the current values, the phase of the rotating magnetic field on the secondary side ( θ) and rotational angular velocity (ω) are estimated, and the excitation current component Id and torque current component Iq are obtained by converting the three-phase current into Cartesian coordinate transformation and dq (direct-quadrature) coordinate transformation.

When the speed command is supplied from the outside to the control circuits 42A and 42B, the current commands Idref and Iqref are generated based on the estimated phase θ, the rotational angular velocity ω and the current components Id and Iq. When the current commands Idref and Iqref are converted into voltage commands Vd and Vq, rectangular coordinate transformation and three-phase coordinate transformation are performed.

Finally, a drive signal is generated as a PWM signal and output to the windings of each phase of the respective motors 5, 22, 28 via inverter circuits 34, 38, 40.

In the above configuration, the inverter circuit 34, the control circuits 42A and 42B, the driving power supply circuit 43, the reactor 44, the rectifier circuit 47, and the IGBT 48 constitute the driving device 60. .

Next, the operation of this embodiment will be described with reference to FIGS. 4 to 8. 4 is a flowchart schematically illustrating a series of process operations of a laundry dryer. After pouring water to the drum 7 for the first time, the drum 7 is inverted at a rotation speed of about 46 rpm to perform the washing operation (step S1).

Then, after the intermediate dehydration, water is poured again to perform the rinsing operation, but the rotation speed of the drum 7 in the intermediate dewatering is about 1200 rpm, and the rinsing operation is about 46 rpm which is the same as the washing operation (step S2). .

Subsequently, when the final dehydration is performed at a rotational speed of about 1700 rpm, the compressor 27 and the fan 24 are operated to invert the air to the drum 7, while inverting the rotation to about 46 rpm to perform a dehumidification drying operation. (Step S3).

5 is a flowchart showing a process of controlling the drive power supply voltage by switching the IGBT 48, which is the short circuit means, by the control circuit 42B during the series of operations shown in FIG. If the drum 7 is inverted at about 46 rpm in the washing operation or the rinsing operation (step S11: YES), the IGBT48 is kept off and the input side of the full-wave rectifying circuit 45 is not shorted. In other words, the boosting operation is not performed (step S12).

When the drum 7 is rotated at a high speed such as intermediate dehydration or final dewatering operation (step S13: YES), the IGBT48 is rotated a plurality of times in a half cycle of the AC power supply voltage (between zero cross points of voltage waveforms). The pulse signal (short pulse) is provided to a gate so that it may turn on, and the input side of the full-wave rectifier circuit 45 is short-circuited (step S14).

That is, when the input side of the full-wave rectifier circuit 45 is shorted by turning on the IGBT48, electron energy can be accumulated in the reactor 44 during that time. If the IGBT48 is turned off afterwards, the current corresponding to the accumulated energy is supplied to the reactor ( 44), the boosting operation is performed.

At this time, even if the time for turning on the IGBT48 is long, the electron energy accumulated in the reactor 44 is saturated, and thus there is a limit to the voltage that can be boosted by one short circuit. However, if the short-circuit is performed by turning on the IGBT48 a plurality of times within a half cycle of the AC power supply voltage, the boosted voltage can be increased in accordance with the number of times.

In the present embodiment, the AC current is detected by the current sensor 52. However, since the voltage and the current are in phase in the commercial AC power supply, the zero cross point of the AC current corresponds to the zero cross point of the AC voltage. .

In addition, when the drum 7 is not reversed like the washing and rinsing operation and the drum 7 is not rotated at high speed like the dehydration operation (step S13: NO), the condenser 27 operates. It is judged whether or not a large current is flowing (for example, 600 W or more in power consumption) by the presence of the current (step S15).

If a large current flows (step S15), for example, when the rotation speed of the comp motor 28 rises or the refrigerant pressure rises, for example, when operating in a drying operation or an air conditioner function that sends cold air to the room, etc., The IGBT48 is turned on once in the half cycle of the AC power supply voltage, and the input side of the full-wave rectifier circuit 45 is shorted (step S16).

In this case, there is no step-up operation, and the operation (high frequency suppression operation) improves the power factor of the power supply.

FIG. 6 is a time chart showing the stroke from washing to dehydration, and shows the stroke in more detail than the flow of FIG. 4. The weight of the laundry is sensed before starting the water supply, and the shower water and intermediate dewatering are repeated twice before the rinsing operation is performed.

FIG. 7 shows a state in which the power supply voltage is changed when the power supply control is performed as shown in FIG. 5. As the operating state of the laundry dryer, dehydration is performed and the compressor 27 is operated. The total input power is about 650 W ( AC power supply voltage 105V).

As shown in Fig. 7A, when the IGBT48 is kept in the OFF state, the DC voltage, which is 295V with the output current at zero, drops to 230V under the influence of the output current and the line impedance.

From this state, as shown in Fig. 7 (b), when the IGBT48 is turned on only once in a half cycle of the AC power supply voltage (corresponding to step S16), the power factor of the AC current is improved, and the high frequency is also reduced. The voltage is rising to 265V.

As shown in Fig. 7C, when the IGBT 48 is turned on twice in a half cycle of the AC power supply voltage (corresponding to step S14), the DC voltage rises to 295V. In this case, the on-time of the IGBT48 is turned on for 0.6 msec after 2 msec from the zero cross point and for 0.3 msec after 2 msec.

FIG. 8A shows the maximum rotational speed of the drum motor 5 that can be reached when the DC power supply voltage is changed, and the maximum rotational speed also increases as the power supply voltage increases. Therefore, it becomes possible to shorten the time of dehydration operation and a drying operation.

8B shows the power consumption of the inverter circuit 34 when the voltage is changed in the same manner and the rotation speed of the drum motor 5 is set to 1200 rpm.

In this case, it can be seen that power consumption is decreasing as the power supply voltage is increased, and the reduction rate is 7.6% at 240W to 223W.

As described above, according to the present embodiment, the control circuit 42B propagates between zero cross timings of the voltage waveforms of the AC power supply by the IGBT48 in accordance with the change in the rotation speed of the drum motor 5 which is a control parameter in the case of performing dehydration operation. The number of times of shorting between the input terminals of the rectifier circuit 45 was changed.

Therefore, it is possible to effectively use the electron energy stored in the reactor 44 and to boost the DC power supply voltage output from the rectifier circuit 45 higher.

Thereby, the rotation speed of the drum motor 5 can be raised higher in dewatering operation to improve dewatering efficiency, and current consumption can be suppressed to save energy.

In the case where the short circuit is performed twice between the zero cross timings of the voltage waveforms, the control circuit 42B shortens the short time as the timing at which the voltage waveforms are higher is high, thus reducing the deformation of the AC current waveform to reduce the power factor. It can be improved. In addition, the IGBT 35 constituting the inverter circuit 34 can be protected.

In addition, even when the dehydration operation is performed and the compressor 27 is driven, the control circuit 42B is connected between the input terminals of the rectifier circuit 45 by the IGBT48 in accordance with the change of the output current which is a parameter controlling the compressor 27. To change the number of shorts.

Accordingly, when a large current flows through the compressor 23, the power factor can be improved to reduce the high frequency and increase the DC power supply voltage to suppress current consumption.

(Second Embodiment)

9 and 10 are the second embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted, and other parts will be described below. FIG. 9 is a diagram corresponding to FIG. 6 and shows a case where the laundry dryer performs the drying operation after the final dehydration is performed.

At this time, the final dehydration is carried out in four stages, and the highest rotational speed of the drum motor 5 in each dewatering operation is set to rise to 400 rpm, 700 rpm, 950 rpm, and 1700 rpm in order.

FIG. 10 shows details of the process corresponding to step S14 of FIG. It is determined whether the setting of the rotation speed is 950 rpm or more (step S21), and if it is 950 rpm or more (Yes), it is also determined whether it is 1450 rpm or more (step S22). Then, if it is 1450 rpm or more (Yes), the short-circuit pulse is output three times (step S23), and the input terminal of the rectifier circuit 45 is short-circuited three times within a half cycle of the AC power supply voltage, and the DC power supply voltage is raised to increase. Let's do it.

If the rotation speed is less than 1450 rpm in step S22 (No), the short-circuit pulse is output twice in the same manner as in the first embodiment (step S25). The rotational speed is set at 1450 rpm as the threshold in step S22 because the intermediate dehydration in the washing operation is 1200 rpm.

As described above, according to the second embodiment, the control circuit 42B increases the number of short circuits between the input terminals of the rectifier circuit 45 as the rotation speed of the drum motor 5 increases when dehydration operation is performed. By increasing the DC power supply voltage, the rotation speed of the motor 5 can be increased.

(Third Embodiment)

Fig. 11 is a third embodiment, and a part different from the second embodiment will be described. FIG. 11 is a diagram corresponding to FIG. 10, and the contents of the determination in steps S21A and S22A changed to steps S21 and S22 differ.

The control circuit 42B detects the AC input current (control parameter) of the driving power supply circuit 43 by the current sensor 52, and determines whether the effective value of the current is 3 amps [A] or more. (Step S21A). If the current effective value is 3 amps or more (Yes), it is further determined whether it is 5 amps or more (step S22A). Then, if it is 5 amps or more (Yes) (step S23), the short-circuit pulse is output three times, and the input terminal of the rectifier circuit 45 is short-circuited three times within a half cycle of the AC power supply voltage.

If less than 5 amps (No), step S25 is executed to output the short pulse twice.

That is, the magnitude of the AC input current in the driving power supply circuit 43 corresponds to the height of the rotational speed of the drum motor 5, so that the same effect as in the second embodiment can be obtained even in the third embodiment. .

(Example 4)

12 is a fourth embodiment, and a part different from the third embodiment will be described. FIG. 12 corresponds to FIG. 11 and changes to the AC input current of the driving power supply circuit 43 in steps S21A and S22A, and changes the input current (control parameter) of the drum motor 5 to FIG. Detect by value. In this case, for example, the current sensor may be disposed on either of the power bus lines of the inverter circuit 34.

Then, the control circuit 42B determines whether the input current rms value of the drum motor 5 is 1.5 amps or more (step S21B), and if the current rms value is 1.5 amps or more (Yes), further, 2.2A. It is judged whether or not it is abnormal (step S22B).

If the current effective value is 2.2 A or more (example of step S22B), step S23 is executed to output the short-circuit pulse three times. If less than 5 amps (No), step S25 is executed to output the short pulse twice.

That is, since the magnitude of the AC input current of the drum motor 5 corresponds to the height of the rotation speed of the drum motor 5, the same effect as that of the third embodiment is obtained also in the case of the fourth embodiment.

(Fifth Embodiment)

Fig. 13 is a fifth embodiment, and a part different from the third embodiment and the like will be described.

FIG. 13 is a diagram corresponding to FIG. 11, and detects the AC input power (control parameter) of the driving power supply circuit 43 in steps S21C and S22C which are switched to steps S21A and S22A.

In this case, what is necessary is just to arrange | position the voltage sensor which measures an AC input voltage as needed. Then, the control circuit 42B determines whether or not the input power of the driving power supply circuit 43 is 300 watts [W] or more (step S21C), and if the input power is 300 watts or more (Yes), It is determined whether or not 500 watts or more (step S22C).

If it is 500 watts or more (Yes), step S23 is executed. If it is less than 500 watts (No), step S25 is executed.

That is, the magnitude of the AC input power of the driving power supply circuit 43 corresponds to the height of the rotational speed of the drum motor 5, so that the same effect as in the third embodiment can be obtained even in the fifth embodiment.

In addition, about step S21C, S22C, you may set a threshold value with respect to the input power of the drum motor 5, and detect the said input power and perform determination similarly to 4th Example.

(Sixth Embodiment)

14 and 15 are the sixth embodiment, and portions different from the second embodiment will be described. FIG. 14 is a diagram corresponding to FIG. 10, and in steps S23A and S25A which are replaced with steps S23 and S25, the control circuit 42B shorts the input terminal of the power supply circuit 43 within a half cycle of the AC power supply. Do it twice.

In step S23A and S25A, the timing of performing two short circuits is changed. 15 shows the corresponding voltage and current waveforms. The short pulse width is the same as in the first embodiment.

In step S25A, the start of the first short circuit is 1.2 msec from the zero cross point of the AC voltage waveform, and the start of the second short circuit is 1.0 msec after the end of the first short circuit (see Fig. 15B). . On the other hand, in step S23A, the first short circuit start is set to 1.7 msec from the zero cross point of the AC voltage waveform, and the second short circuit start is set to 1.0 msec after the first short circuit is finished (Fig. 15 (c)). Reference).

That is, when the AC power supply frequency is 60 Hz, the half cycle is 8.33 msec, so the peak value of the AC voltage becomes a peak after 4.17 msec from the zero cross point. Therefore, the delayed timing of starting the short circuit increases the current value supplied to the reactor 44, so that the boosting effect can be increased (265 V to 295 V).

In addition, Fig.15 (a) is a case where 0.7 msec of 1st short circuit start is started from a zero cross point for a comparison, and the DC voltage is set to 235V.

As described above, according to the sixth embodiment, when the dehydration operation is performed, the control circuit 42B increases the period from the zero cross timing of the AC voltage waveform to the short-circuit when the rotation speed of the drum motor 5 increases. Since it is made long, a boost voltage can be controlled by adjusting a short circuit start period.

(7th-9th Example)

16 to 18 are seventh to ninth embodiments, and show that the short circuit processing in the sixth embodiment described with reference to FIG. 14 is combined with the determination processing for the third to fifth embodiments described with reference to FIGS. 11 to 13. . Also in the case of these 7th-9th Example, the effect similar to 6th Example is acquired.

This invention is not limited only to the Example mentioned above and shown in drawing, The following deformation | transformation or expansion is possible. In other words, the control circuits 42A and 42B may be integrated into one control circuit.

The number of short circuits in the AC power supply half cycle may be set to four or more times.

The pulse width and the delay time from the zero cross point in the case of short-circuiting by IGBT48 can also be appropriately changed.

The semiconductor switching element is not limited to the IGBT but may use a bipolar transistor or a MOSFET.

Setting of the threshold value regarding the rotation speed, the voltage, the current, and the power is an example, and may be appropriately changed according to an individual design.

You may apply to the washing machine which does not have a drying function.

5: drum motor 7: drum
22: fan motor 27: compressor
28: compressor motor 42: control circuit
42B: control circuit (short control means)
34, 38, 40: inverter circuit 43: power supply circuit for driving
44: reactor 45: full-wave rectifier circuit (rectifier circuit)
47: full-wave rectifier circuit (short means) 48: IGBT (short means)
60: drive unit

Claims (6)

Rectifier circuit connected to the AC power supply through the reactor,
Short-circuit means for shorting between input terminals of said rectifier circuit,
An inverter circuit connected to an output side of the rectifier circuit to drive a motor that converts DC power into AC power and generates a rotational driving force for at least dehydration operation; and
And a short circuit control means for changing the number of times of shorting between the input terminals between zero cross timings of the voltage waveform of the AC power supply by the short circuit means in accordance with a change of a control parameter in the case of performing the dehydration operation. Motor drive of washing machine. The method of claim 1,
An inverter circuit for driving a compressor constituting a heat pump for performing a drying operation;
The short-circuit control means changes the number of times of shorting the input terminals by the short-circuit means according to a change of a parameter controlling the compressor even when the dehydration operation is performed and the compressor is driven. Motor-drive unit of the washing machine. The method according to claim 1 or 2,
An input detecting means for detecting power or current input to the inverter circuit,
And the short circuit control means extends the period from zero crossing timing of the voltage waveform to starting a short circuit when the input power or current is large. The method according to claim 1 or 2,
And wherein the short circuit control means increases the number of times of performing the short circuit as the number of rotations of the motor increases when the dehydration operation is performed. The method according to claim 1 or 2,
And the short circuit control means increases the period from zero cross timing of the voltage waveform to starting a short circuit as the rotation speed of the motor increases when dehydration operation is performed. The method of claim 1,
And the short circuit control means shortens the short circuit time when the peak value of the voltage waveform is higher when the short circuit is performed a plurality of times between zero cross timings of the voltage waveform.

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