AU7856487A

AU7856487A – Alternating current motor control apparatus
– Google Patents

AU7856487A – Alternating current motor control apparatus
– Google Patents
Alternating current motor control apparatus

Info

Publication number
AU7856487A

AU7856487A
AU78564/87A
AU7856487A
AU7856487A
AU 7856487 A
AU7856487 A
AU 7856487A
AU 78564/87 A
AU78564/87 A
AU 78564/87A
AU 7856487 A
AU7856487 A
AU 7856487A
AU 7856487 A
AU7856487 A
AU 7856487A
Authority
AU
Australia
Prior art keywords
power
inverter
power failure
control circuit
motor
Prior art date
1986-08-22
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)

Granted

Application number
AU78564/87A
Other versions

AU589803B2
(en

Inventor
Yasutami Kito
Kenji Oshima
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)

Otis Elevator Co

Original Assignee
Otis Elevator Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
1986-08-22
Filing date
1987-08-21
Publication date
1988-03-08

1987-08-21
Application filed by Otis Elevator Co
filed
Critical
Otis Elevator Co

1988-03-08
Publication of AU7856487A
publication
Critical
patent/AU7856487A/en

1989-10-19
Application granted
granted
Critical

1989-10-19
Publication of AU589803B2
publication
Critical
patent/AU589803B2/en

2007-08-21
Anticipated expiration
legal-status
Critical

Status
Ceased
legal-status
Critical
Current

Links

Espacenet

Global Dossier

Discuss

239000004020
conductor
Substances

0.000
claims
description
19

230000001172
regenerating effect
Effects

0.000
claims
description
8

230000008929
regeneration
Effects

0.000
claims
description
6

238000011069
regeneration method
Methods

0.000
claims
description
6

230000003247
decreasing effect
Effects

0.000
claims
description
5

230000001360
synchronised effect
Effects

0.000
claims
description
4

230000006698
induction
Effects

0.000
description
24

238000001514
detection method
Methods

0.000
description
13

239000003990
capacitor
Substances

0.000
description
9

XUIMIQQOPSSXEZ-UHFFFAOYSA-N
Silicon
Chemical group

[Si]
XUIMIQQOPSSXEZ-UHFFFAOYSA-N
0.000
description
3

230000001276
controlling effect
Effects

0.000
description
3

230000003292
diminished effect
Effects

0.000
description
3

229910052710
silicon
Inorganic materials

0.000
description
3

239000010703
silicon
Substances

0.000
description
3

230000005284
excitation
Effects

0.000
description
2

238000009499
grossing
Methods

0.000
description
2

238000000034
method
Methods

0.000
description
2

238000012986
modification
Methods

0.000
description
2

230000004048
modification
Effects

0.000
description
2

230000001105
regulatory effect
Effects

0.000
description
2

125000004122
cyclic group
Chemical group

0.000
description
1

238000010586
diagram
Methods

0.000
description
1

Classifications

B—PERFORMING OPERATIONS; TRANSPORTING

B66—HOISTING; LIFTING; HAULING

B66B—ELEVATORS; ESCALATORS OR MOVING WALKWAYS

B66B1/00—Control systems of elevators in general

B66B1/24—Control systems with regulation, i.e. with retroactive action, for influencing travelling speed, acceleration, or deceleration

B66B1/28—Control systems with regulation, i.e. with retroactive action, for influencing travelling speed, acceleration, or deceleration electrical

B66B1/30—Control systems with regulation, i.e. with retroactive action, for influencing travelling speed, acceleration, or deceleration electrical effective on driving gear, e.g. acting on power electronics, on inverter or rectifier controlled motor

B66B1/308—Control systems with regulation, i.e. with retroactive action, for influencing travelling speed, acceleration, or deceleration electrical effective on driving gear, e.g. acting on power electronics, on inverter or rectifier controlled motor with AC powered elevator drive

B—PERFORMING OPERATIONS; TRANSPORTING

B66—HOISTING; LIFTING; HAULING

B66B—ELEVATORS; ESCALATORS OR MOVING WALKWAYS

B66B1/00—Control systems of elevators in general

B66B1/24—Control systems with regulation, i.e. with retroactive action, for influencing travelling speed, acceleration, or deceleration

B66B1/28—Control systems with regulation, i.e. with retroactive action, for influencing travelling speed, acceleration, or deceleration electrical

B66B1/285—Control systems with regulation, i.e. with retroactive action, for influencing travelling speed, acceleration, or deceleration electrical with the use of a speed pattern generator

B—PERFORMING OPERATIONS; TRANSPORTING

B66—HOISTING; LIFTING; HAULING

B66B—ELEVATORS; ESCALATORS OR MOVING WALKWAYS

B66B1/00—Control systems of elevators in general

B66B1/24—Control systems with regulation, i.e. with retroactive action, for influencing travelling speed, acceleration, or deceleration

B66B1/28—Control systems with regulation, i.e. with retroactive action, for influencing travelling speed, acceleration, or deceleration electrical

B66B1/30—Control systems with regulation, i.e. with retroactive action, for influencing travelling speed, acceleration, or deceleration electrical effective on driving gear, e.g. acting on power electronics, on inverter or rectifier controlled motor

B66B1/302—Control systems with regulation, i.e. with retroactive action, for influencing travelling speed, acceleration, or deceleration electrical effective on driving gear, e.g. acting on power electronics, on inverter or rectifier controlled motor for energy saving

B—PERFORMING OPERATIONS; TRANSPORTING

B66—HOISTING; LIFTING; HAULING

B66B—ELEVATORS; ESCALATORS OR MOVING WALKWAYS

B66B5/00—Applications of checking, fault-correcting, or safety devices in elevators

B66B5/02—Applications of checking, fault-correcting, or safety devices in elevators responsive to abnormal operating conditions

H—ELECTRICITY

H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER

H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS

H02P23/00—Arrangements or methods for the control of AC motors characterised by a control method other than vector control

H02P23/06—Controlling the motor in four quadrants

Description

DESCRIPTION
ALTERNATING CURRENT MOTOR CONTROL APPARATUS
BACKGROUND OF THE INVENTION
This invention relates to an apparatus for controlling an adjustable-speed alternating current (AC) motor coupled to drive an elevator cage.
Electric power converters or inverters have been employed–for- the- application of adjustable-speed drives using alternating current motors. A typical converter includes a direct current (DC) rectifier for rectifying three-phase AC input voltage and for supplying the resulting DC bus potential to an inverter. The inverter comprises a plurality of pairs of series-connected switching elements to generate an adjustable frequency output. In many applications, such a frequency adjustment is effected through a control circuit which employs a pulse width modulation (PWM) control . technique in producing variable frequency gating pulses to periodically switch the respective switching elements so as to operate the AC motor at a variable speed. The AC motor can be propelled (motoring mode) or retarded (braking mode) as desired by ppropriately varying the frequency and the amplitude of the excitation that the inverter applies to the AC motor. The AC motor operation is changed frequency between the motiring and braking modes particularly when the AC motor is used to drive an elevator. It is necessary to flow power from the AC motor back through the

inverter to the converter during the braking mode or other regenerative conditions in order to operate the AC motor with high efficiency.
It is the conventional practice to bring the elevator to a stop by applying a mechanical braking while stopping the inverter operation when a power failure occurs. However, this requires a large-sized mechanical braking system which can absorb the whole inertia energy of the elevator. This is true particularly for large-sized and high-speed elevators. In addition, there is no way to handle the regenerated power when the regenerative function is inhibited in response to the power failure. SUMMARY OF THE INVENTION
There is provided, in accordance with the invention, an apparatus for controlling an adjustable-speed alternating current motor coupled to drive an elevator cage. The apparatus includes a converter connected to a source of AC power for converting the AC power into DC power, and an inverter connected through relatively positive and negative conductors to the converter for inverting the DC power into AC output power having adjustable frequency, voltage magnitude and current magnitude to drive the motor. The converter includes regeneration means controlled to permit flow of power from the inverter to the power source during regenerative conditions. The apparatus also includes a control circuit

for controlling the inverter to drive the motor at an adjustable speed. The control circuit includes means responsive to a power failure for disabling the regeneration means to prevent flow of power to the power source and reducing the current magnitude of the inverter output power to a predetermined minimum limit enough to maintain a synchronous relationship between the inverter and the» motor. The control circuit includes means for connecting an electric resistor between the relatively positive and negative conductors to provide a dynamic braking of the motor after the power failure continues for a predetermined time. BRIEF DESCRIPTION OF THE DRAWINGS
This invention will be described in greater detail by reference to the following description taken in connection with the accompanying drawings, in which:
Fig. 1 is a schematic block diagram showing one embodiment of an alternating current motor control apparatus made in accordance with the invention; and
Fig. 2A-2H are graphic illustrations used in explaining the operation of the invention. DETAILED DESCRIPTION OF THE INVENTION
With reference now to the drawings, and particularly to Fig. 1, a converter system 20 includes input conductors 11, 12 and 13 for receiving electric power from a suitable three-phase AC power source 10. The input conductors 11, 12 and 13 carry this power to a

three-phase power rectifier 21 which is operative to convert alternating voltage to unipolarity voltage for energizing a DC link shown as the relatively positive conductor 22 and the relatively negative conductor 23. The power rectifier 21 is shown as including a plurality of parallel pairs of series-connected diodes. A capacitor 24 spans the DC link for smoothing the rectified power. The unipolarity- voltage -across the- smσothi*ng «capacitor 24 is applied to respective DC input terminals 30a and 30b of a power inverter 30. The inverter 30 is shown as including a plurality of parallel pairs of series-connected power transistors arranged and controlled to convert the DC input power into three-phase AC output power having adjustable frequency and voltage magnitude. For this purpose, each of the power transistors has its base or controlled electrode coupled to a control circuit 50 which will supply the power transistors with cyclic gate pulses to turn on the power transistors in a predetermined sequence and at a desired frequency. The power transistors may be replaced with silicon controlled rectifiers or other switching elements to obtain the same result. The three-phase AC output is supplied through output conductors 31, 32 and 33 to a three-phase induction motor 40 which is used to drive an elevator passenger cage (not shown) .
The induction motor 40 can be propelled (motoring mode) or retarded (braking mode) as desired by

appropriately varying the frequency and the amplitude of the excitation that the inverter 30 applies to the induction motor 40. For this purpose, the control circuit 50 regulates and controls the operation of the inverter 30 in programmed response to a plurality of input signals which may comprise a signal representing the desired motor speed and a feedback signal representative of the actual motor speed. The control circuit 50 utilizes a pulse width modulation (PWM) control technique to produce gating pulses so as to periodically switch the respective power transistors of the inverter 30 in accordance with a speed pattern programmed into the control circuit 50.
During the normal operation of the inverter 30, the flow of energy is from the converter system 20 through the inverter 30 to the induction motor 40. However, during regenerative conditions, power may flow from the induction motor 40, which is now acting an energy source, back through the inverter 30 to charge the capacitor 24.
The inverter 30 includes feedback diodes each connected across the corresponding power transistor in inverse parallel relationship therewith for passage of current regenerated in the induction motor 40 to charge the capacitor 24, for example, during an induction motor braking mode. Additionally, the converter system 20 also includes a. plurality of parallel pairs of series-connected power transistors arranged and controlled to feed the regenerated current to the AC power source 10. For this

purpose, each of the power transistors has its base or controlled electrode coupled to the control circuit 50. These power transistors may be replaced with silicon controlled rectifiers or other switching elements to obtain the same result.
The control circuit 50 operates on regulated DC power supplied from a constant-voltage regulated power source (PS) -52 which is- supplied *with DC power from the converter system 20. The control circuit 50 receives inputs from various detection circuits including a power failure detection circuit (PF) 54 and a voltage shortage detection circuit (VS) 56. The power failure detection circuit 54 has three inputs connected to the respective input conductors 11, 12 and 13 for produce a power failure indication signal NV when a power failure such as power interruption, open-phase, or the like occurs. The voltage shortage detection circuit 56 has two inputs connected to the respective positive and negative conductors 22 and 23 for producing a voltage shortage indication signal UV when a voltage drop appears in the AC power source 10 or the inverter system 20. These signals NV and UV are applied to the control circuit 50.
As shown in Fig. 1, the smoothing capacitor 24 is connected in parallel with a braking resistor 60 which is connected in series with a power transistor 62. The power transistor 62 has a base or controlled electrode connected to the output of an AND gate 64. The AND gate

64 has an input connected to the control circuit 50 and another input connected to an overvoltage detection circuit (OV) 66. The overvoltage detection circuit 66 has two inputs connected to the positive and negative conductors 22 and 23 for producing an overvoltage indication signal OV in the form of a high-level signal to the AND gate 64 when an overvoltage appears at the output of the converter system 20. It is to be noted, of course, that the power transistor 62 may be replaced with a silicon controlled rectifiers or other switching elements. In response to the power failure indication signal NV or the voltage shortage indication signal UV, the control circuit 50 carries out the following controls. First, the control circuit 50 controls the power transistors of • the converter system 20 to interrupt the regenerated current flow to the AC power source 10. This is effective to protect the power transistors from breakage due to excessive current flow caused when a power failure occurs during a regenerative condition. Second, the control circuit 50 controls the inverter 30 to reduce its output current to a predetermined minimum limit enough to maintain the synchronous relationship between the inverter 30 and the induction motor 40. This is effective to maintain the induction motor running while minimizing the DC voltage drop across the conductors 22 and 23 so as to facilitate the resumption of the induction motor operation after removal of the power failure. Third, the

control circuit 50 produces a high-level signal to open the AND gate 64. The output of the AND gate 64 changes to its high level turning on the power transistor 62 so as to connect the braking resistor 60 across the capacitor 24 when the overvoltage detection circuit 66 produces an overvoltage indication signal OV. This is effective to protect the power transistors and the capacitor 24 from breakage» «duetto Excessive current flow caused after the regenerated current flow is interrupted.
The operation of the invention may be better understood by referring to Figs. 2A to 2H. It is assumed that a power failure occurs at time tO, as shown in Fig. 6B, during the normal operation where the control circujit 50 controls the inverter 30 to operate the induction motor 40 at a target speed Ns, as shown in Fig. 2A. At time tl, the power failure detection circuit 54 or the voltage shortage detection circuit 56 produces a signal indicative of the power failure to the control circuit 50, as shown in Fig. 2D. In response to this failure indication signal, the control circuit 50 turns off the power transistors of the inverter system 20 to prevent regenerated current flow to the AC power source 10, as shown in Fig. 2F, controls the inverter 30 to reduce the output current to the induction motor 40 to a predetermined minimum limit enough to maintain the synchronous relationship between the converter 30 and the induction motor 40, as shown in Fig. 2H, and produces a

high-level signal to open the AND gate 64. It is to be noted that the output of the AND gate 64 remains low until the overvoltage detection circuit 66 produces an overvoltage indication signal OV.
As long as the power failure continues for a predetermined time TD, for example, several tens of seconds, the control circuit 50 confirms the power failure, as shown in Fig. 2E, and controls the inverter ’30 ‘ to operate the induction motor 40 at a decreasing speed, as shown in Fig. 2A, while at the same time permitting the DC voltage to increase, as shown in Fig. 2C. Under this control, current will flow from the induction motor 40 through the inverter 30 to charge the capacitor 24, causing an excessive voltage across the conductors 22 and 23. The overvoltage detection circuit 66 detects this excessive voltage and generates the overvoltage indication signal OV. Since the AND gate 64 has been open, the overvoltage indication signal OV changes the output of the AND gate 64 to its high level turning on the power transistor 62 to connect the braking resistor 60 across the capacitor 24. Under this condition, the braking resistor 60 serves to provide a dynamic braking so as to slow down the induction motor 40 and reduce the regenerated current. At time t5 when the voltage across the conductors 22 and 23 drops below a predetermined level, the overvoltage detection circuit 66 stops generating the overvoltage indication signal OV and turns

off the power transistor 62 so as to release the dynamic braking. Thereafter, a mechanical braking is used to bring the elevator to a stop.
It is to be noted that, during the period between time tl and time t4r the inverter 30 operates in a normal manner except for its output current being at a predetermined minimum limit. Assuming now that the power failure is -diminished at time t3 which is prior to time t4, as shown by the broken line of Fig. 2B, the power failure indication signal is diminished at time t3, as shown by the broken line of Fig. 2D, and thus, the control circuit 50 controls the inverter 30 to return its output current to its initial magnitude, as shown by the broken line of Fig. 2H, and turns on the power transistors of the converter system 20 to permit flow of regenerated current to the AC power source 10, as shown by the broken line of Fig. 2F. In addition, the control circuit 50 holds the AND gate 64 closed to prevent the dynamic braking function of the braking resistor 60, as shown by the broken line of Fig. 2G.
As described previously, the control circuit 50 is responsive to a power failure for stopping the regeneration function and reducing the inverter output current to a predetermined minimum level enough to maintain a synbchronous relationship between the inverter 30 and the induction motor 40. If the power failure is diminished within the predetermined time T , the control

circuit 50 returns the inverter 30 to its normal operation mode. Otherwise, the control circuit 50 commands application of a dynamic braking of the induction motor 40. If a power failure occurs during a regenerative condition, the overvoltage detector 66 will produce an overvoltage indication signal to start the application of the dynamic braking of the induction motor before the lapse of the time TD so that-the induction «motor 40* can come to a stop.
After the power failure continues for a predetermined time, the control circuit 50 controls the inverter 30 to operate the induction motor 40 at a decreasing speed by gradually decreasing the speed command signal Ns which is obtained from a speed pattern. However, such control may be made by decreasing the inverter output current to maintain the induction motor 40 at a constant torque. In addition, the control circuit 50 may be arranged to control the inverter 30 to increase the induction motor speed again so that the inverter can return to its normal operation or to restart the induction motor after it is stopped when the power supply is resumed after the power failure continues for the predetermined time. These control patterns can be realized merely be modifying the speed pattern. Another control pattern may be employed to provide a motoring torque required to bring the elevator passenger cage to the nearest floor after the power failure continues for the predetermined time.

It is apparent from the foregoing that there has been provided, in accordance with the invention, an alternating current motor control apparatus which permits the motor to operate in a normal manner without any speed reduction in the event of a power failure which diminished within a predetermined time. After the power failure continues for the predetermined time, the motor is decelerated by a dynamic braking in the early stage of the motor braking mode and a mechanical braking is employed in the subsequent stage of the motor braking mdoe. This is effective to ensure that the elevator comes to a stop safely. In addition, this permits the use of a compact mechanical braking system having a relatively small braking force.
While the invention has been described in conjunction with a specific embodiment thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all alternatives, modifications and variations that fall within the scope of the appended claims.

Claims (7)

WHAT IS CLAIMED IS:

1. An apparatus for controlling an adjustable-speed alternating current motor coupled to drive an elevator cage, comprising: a converter connected to a source of AC power for converting the AC power into DC power; an inverter connected through relatively positive and negative conductors- to»—he- converter for inverting the DC power into AC output power having adjustable frequency, voltage magnitude and current magnitude to drive the motor; the converter including regeneration means controlled to permit flow of power from the inverter to the power source during regenerative conditions; an electric resistor; an control circuit for controlling the inverter to drive the motor at an adjustable speed, the control circuit including means responsive to a power failure for disabling the regeneration means to prevent flow of power to the power source and reducing the current magnitude of the inverter output power to a predetermined minimum limit enough to maintain a synchronous relationship between the inverter and the motor, the control circuit including means for connecting the electric resistor between the relatively positive and negative conductors to provide a dynamic braking of the motor when the power failure continues for a predetermined time.

2. The apparatus as claimed in claim 1, wherein the control circuit includes means for returning the current magnitude of the inverter output power to its initial value when the power failure continues for the predetermined time.

3. The apparatus as claimed in claim 2, wherein the control circuit includes means for controlling the inverter to drive the electric motor at a decreasing speed when the power failure continues for a predetermined time.

4. The apparatus as claimed in claim 3, wherein the control circuit includes an overvoltage detector connected between the relatively positive and negative conductors for producing an overvoltage indication signal when the voltage between the relatively positive and negative conductors exceeds a predetermined value, means for providing a command signal when the power failure continues for the predetermined time, and means for connecting the electric resistor between the relatively positive and negative conductors in the presence of both of the overvoltage indication signal and the command signal.

5. The apparatus as claimed in claim lr wherein the regeneration means includes a plurality of switching element controlled to permit flow of power from the inverter to the power source during regenerative conditions when they are turned on.

6. The apparatus as claimed in claim 5, wherein the control circuit includes a power failure detector connected between the relatively positive and negative conductors for producing a power failure indication signal when the voltage between the relatively positive and negative conductors drops below a predetermined value, and means respective to the power failure indication signal for turning off the switching elements and reducing the current magnitude of the inverter output power to the predetermined minimum limit.

7. The apparatus as claimed in claim 5, wherein the control cicuit includes a power failure detector connected to the power source for producing a power failure indication signal when the voltage at an output of the power source drops below a predetermined value, and means responsive to the power failure indication signal for turning off the switching elements and reducing the current magnitude of the inverter output power to the predetermined minimum limit.

AU78564/87A
1986-08-22
1987-08-21
Alternating current motor control apparatus

Ceased

AU589803B2
(en)

Applications Claiming Priority (2)

Application Number
Priority Date
Filing Date
Title

JP61197569A

JPS6356183A
(en)

1986-08-22
1986-08-22
Invertor for driving elevator

JP61-197569

1986-08-22

Publications (2)

Publication Number
Publication Date

AU7856487A
true

AU7856487A
(en)

1988-03-08

AU589803B2

AU589803B2
(en)

1989-10-19

Family
ID=16376683
Family Applications (1)

Application Number
Title
Priority Date
Filing Date

AU78564/87A
Ceased

AU589803B2
(en)

1986-08-22
1987-08-21
Alternating current motor control apparatus

Country Status (9)

Country
Link

US
(1)

US4902954A
(en)

EP
(1)

EP0278988B1
(en)

JP
(1)

JPS6356183A
(en)

KR
(1)

KR950015173B1
(en)

AU
(1)

AU589803B2
(en)

BR
(1)

BR8707426A
(en)

DE
(1)

DE3786912T2
(en)

FI
(1)

FI95425C
(en)

WO
(1)

WO1988001450A1
(en)

Cited By (1)

* Cited by examiner, † Cited by third party

Publication number
Priority date
Publication date
Assignee
Title

AU600066B2
(en)

*

1987-01-13
1990-08-02
Kone Elevator Gmbh
Method for controlling the semiconductor switches of a rectifier bridge connected to an A.C. mains supply, and a control unit designed for applying the method

Families Citing this family (45)

* Cited by examiner, † Cited by third party

Publication number
Priority date
Publication date
Assignee
Title

JPS63137597U
(en)

*

1987-02-26
1988-09-09

JPH0697875B2
(en)

*

1987-05-20
1994-11-30
日本オ−チス・エレベ−タ株式会社

Inverter for driving elevator

US4876637A
(en)

*

1988-03-22
1989-10-24
Kabushiki Kaisha Toshiba
Power converter and method of controlling the same

FI86053C
(en)

*

1989-10-31
1992-07-10
Kone Oy

Method and apparatus for controlling a lifting motor

JPH0496677A
(en)

*

1990-08-13
1992-03-30
Nippon Otis Elevator Co
Operation confirming unit of dynamic brake circuit for elevator

US5170105A
(en)

*

1991-03-08
1992-12-08
General Electric Company
Method for determining operability of an electrical dynamic braking system

JPH04322186A
(en)

*

1991-04-22
1992-11-12
Hitachi Ltd
Motor-operated door device

FR2676095A1
(en)

*

1991-05-02
1992-11-06
Alavoine Jean Pierre
Device for regulating the pumping rate and for the protection of beam engine pumps

DE4138596A1
(en)

*

1991-11-23
1993-05-27
Buehne Werner Abus Kg

LIFTING WORKING WITH VARIABLE LIFTING SPEED

US5361565A
(en)

*

1993-01-19
1994-11-08
Bayer Robert F
Elevating system

US5672950A
(en)

*

1994-08-16
1997-09-30
Itt Corporation
Voltage, phase and frequency control by miniature inverter system

US5471125A
(en)

*

1994-09-09
1995-11-28
Danfoss A/S
AC/DC unity power-factor DC power supply for operating an electric motor

FI112733B
(en)

*

1994-09-30
2003-12-31
Kone Corp

Method and apparatus for braking a synchronous motor

JP3627303B2
(en)

*

1995-08-11
2005-03-09
日立工機株式会社

Centrifuge

JP3330050B2
(en)

*

1997-03-11
2002-09-30
本田技研工業株式会社

Electric vehicle control device

US5814955A
(en)

*

1997-03-14
1998-09-29
Eaton Corporation
Motor control circuit with a low voltage monitor

US6005362A
(en)

*

1998-02-13
1999-12-21
The Texas A&M University Systems
Method and system for ride-through of an adjustable speed drive for voltage sags and short-term power interruption

AT411506B
(en)

*

2000-10-02
2004-01-26
Siemens Ag Oesterreich

SWITCHING REGULATOR

JP2003037990A
(en)

*

2001-07-24
2003-02-07
Hitachi Ltd
Motor control device

US6686718B2
(en)

2001-11-27
2004-02-03
York International Corp.
Control loop and method for variable speed drive ride-through capability improvement

US7414377B2
(en)

*

2002-09-23
2008-08-19
Siemens Energy & Automation, Inc.
System and method for automatic current limit control

KR100500525B1
(en)

*

2003-02-12
2005-07-12
삼성전자주식회사
Power Supply Device For Motor

JP2005016958A
(en)

*

2003-06-23
2005-01-20
Fanuc Ltd
Motor driving device

AT504808B1
(en)

*

2003-11-14
2009-08-15
Bernecker & Rainer Ind Elektro

SYNCHRONOUS MACHINE

US7116067B2
(en)

*

2004-09-21
2006-10-03
Honeywell International Inc.
Power converter controlling apparatus and method providing ride through capability during power interruption in a motor drive system

US20060131462A1
(en)

*

2004-12-20
2006-06-22
Holland Leo D
Turboelectric arresting gear

FI117938B
(en)

*

2005-10-07
2007-04-30
Kone Corp

Lift system

NL1030489C1
(en)

*

2005-11-22
2007-05-23
Maasland Nv

Feeding device.

JP5363112B2
(en)

*

2005-11-23
2013-12-11
オーチス エレベータ カンパニー

System and method for continuously driving hoisting motor for elevator with non-standard power source

US7607896B2
(en)

*

2006-04-28
2009-10-27
Baker Hughes Incorporated
Systems and methods for power ride-through in variable speed drives

JP4986541B2
(en)

*

2006-08-31
2012-07-25
東芝エレベータ株式会社

Elevator control device

CN101971474A
(en)

*

2008-02-20
2011-02-09
莫斯科技株式会社
Magnetic energy recovery switech having protective circuit

CN101340174B
(en)

*

2008-08-08
2010-08-04
周顺新
System asynchronously implementing frequency conversion and speed regulation of rotor by dragging multiple motors with inverter

FI120854B
(en)

*

2008-09-08
2010-03-31
Kone Corp

Power Supply Arrangement for Transport System

JP5872692B2
(en)

2011-06-21
2016-03-01
トゥエルヴ, インコーポレイテッド

Artificial therapy device

CN103782502B
(en)

2011-07-26
2017-11-17
莫戈公司
motor clamping system

US11202704B2
(en)

2011-10-19
2021-12-21
Twelve, Inc.
Prosthetic heart valve devices, prosthetic mitral valves and associated systems and methods

US9039757B2
(en)

2011-10-19
2015-05-26
Twelve, Inc.
Prosthetic heart valve devices, prosthetic mitral valves and associated systems and methods

EP2750630B1
(en)

2011-10-19
2021-06-30
Twelve, Inc.
Device for heart valve replacement

CN114903657A
(en)

2011-10-19
2022-08-16
托尔福公司
Prosthetic heart valve devices, prosthetic mitral valves, and related systems and methods

JP5260719B2
(en)

2011-11-30
2013-08-14
ファナック株式会社

Motor drive device having power failure determination unit for determining presence or absence of power failure

JP6004970B2
(en)

*

2013-03-05
2016-10-12
三菱電機株式会社

Motor drive control device, air conditioner, ventilation fan and heat pump water heater

US10919730B2
(en)

2016-03-18
2021-02-16
Otis Elevator Company
Management of mutiple coil brake for elevator system

EP3617110B1
(en)

*

2018-08-30
2022-02-23
KONE Corporation
Elevator motor drive including safety control of elevator in case of power failure

JP7003965B2
(en)

*

2019-04-23
2022-01-21
フジテック株式会社

Passenger conveyor

Family Cites Families (20)

* Cited by examiner, † Cited by third party

Publication number
Priority date
Publication date
Assignee
Title

US3829757A
(en)

*

1970-07-18
1974-08-13
Hoechst Ag
System for controlling the frequency of an alternating current converter in response to load changes

BE790067A
(en)

*

1971-10-13
1973-04-13
Westinghouse Air Brake Co

ENGINE CONTROL SYSTEM

US4051418A
(en)

*

1975-11-03
1977-09-27
Berto Gerald N O
Three phase a.c. motor drive system

JPS5822959B2
(en)

*

1977-10-31
1983-05-12
神鋼電機株式会社

Control device for instantaneous voltage drop of input power supply of inverter

JPS5840918B2
(en)

*

1979-08-15
1983-09-08
ファナック株式会社

Electric motor operation control device

JPS57208895A
(en)

*

1981-06-16
1982-12-22
Fanuc Ltd
Controlling system of induction motor

JPS5812578A
(en)

*

1981-07-15
1983-01-24
Fuji Electric Co Ltd
Inverter device

US4445167A
(en)

*

1981-10-05
1984-04-24
Tokyo Shibaura Denki Kabushiki Kaisha
Inverter system

JPS5889572A
(en)

*

1981-11-16
1983-05-27
三菱電機株式会社
Operating device for alternating current elevator

JPS58154380A
(en)

*

1982-03-09
1983-09-13
Mitsubishi Electric Corp
Controller for ac elevator

JPS5914393A
(en)

*

1982-07-15
1984-01-25
Fuji Electric Co Ltd
Control system for inverter

JPS5980195A
(en)

*

1982-10-27
1984-05-09
Hitachi Ltd
Controller for elevator

JPS59149781A
(en)

*

1983-02-16
1984-08-27
Mitsubishi Electric Corp
Controller for elevator

JPH067754B2
(en)

*

1983-08-15
1994-01-26
株式会社日立製作所

Induction motor controller

DE3341952A1
(en)

*

1983-11-21
1985-05-30
Siemens AG, 1000 Berlin und 8000 München

METHOD AND DEVICE FOR THE OPERATION OF A LOAD SUPPLIED BY A CURRENT INTERCONNECTOR, ESPECIALLY AN ASYNCHRONOUS MACHINE, WHEN THE MAINS FAILURE

JPS60170483A
(en)

*

1984-02-14
1985-09-03
Mitsubishi Electric Corp
Controller of ac elevator

JPH0634624B2
(en)

*

1984-06-28
1994-05-02
株式会社日立製作所

Instantaneous power failure restart device for voltage-type inverter

JPS6188774A
(en)

*

1984-10-05
1986-05-07
Mitsubishi Electric Corp
Controller for elevator

JPS62107698A
(en)

*

1985-10-31
1987-05-19
Mitsubishi Electric Corp
Power interruption time stopping circuit for inverter

US4761600A
(en)

*

1987-03-06
1988-08-02
General Electric Company
Dynamic brake control

1986

1986-08-22
JP
JP61197569A
patent/JPS6356183A/en
active
Pending

1987

1987-08-21
AU
AU78564/87A
patent/AU589803B2/en
not_active
Ceased

1987-08-21
WO
PCT/JP1987/000623
patent/WO1988001450A1/en
active
IP Right Grant

1987-08-21
KR
KR1019880700431A
patent/KR950015173B1/en
not_active
IP Right Cessation

1987-08-21
EP
EP87905479A
patent/EP0278988B1/en
not_active
Expired – Lifetime

1987-08-21
BR
BR8707426A
patent/BR8707426A/en
not_active
IP Right Cessation

1987-08-21
US
US07/196,199
patent/US4902954A/en
not_active
Expired – Fee Related

1987-08-21
DE
DE87905479T
patent/DE3786912T2/en
not_active
Expired – Fee Related

1988

1988-04-18
FI
FI881794A
patent/FI95425C/en
not_active
IP Right Cessation

Cited By (1)

* Cited by examiner, † Cited by third party

Publication number
Priority date
Publication date
Assignee
Title

AU600066B2
(en)

*

1987-01-13
1990-08-02
Kone Elevator Gmbh
Method for controlling the semiconductor switches of a rectifier bridge connected to an A.C. mains supply, and a control unit designed for applying the method

Also Published As

Publication number
Publication date

KR880702000A
(en)

1988-11-07

BR8707426A
(en)

1988-11-01

AU589803B2
(en)

1989-10-19

WO1988001450A1
(en)

1988-02-25

DE3786912D1
(en)

1993-09-09

DE3786912T2
(en)

1993-11-11

FI881794A0
(en)

1988-04-18

EP0278988B1
(en)

1993-08-04

JPS6356183A
(en)

1988-03-10

KR950015173B1
(en)

1995-12-23

FI95425C
(en)

1996-01-25

FI881794A
(en)

1988-04-18

US4902954A
(en)

1990-02-20

FI95425B
(en)

1995-10-13

EP0278988A1
(en)

1988-08-24

Similar Documents

Publication
Publication Date
Title

AU589803B2
(en)

1989-10-19

Alternating current motor control apparatus

US5070290A
(en)

1991-12-03

Alternating current motor control system with emergency control responsive to failure of power supply

KR900005815B1
(en)

1990-08-11

Power failure stop circuit for a converter

US4879639A
(en)

1989-11-07

Power converter for driving an AC motor at a variable speed

US5726550A
(en)

1998-03-10

Motor control system for centrifuge

KR930008465B1
(en)

1993-09-04

Inverter power transistor protection

US5932979A
(en)

1999-08-03

PWM speed-control apparatus for elevators

JPH069164A
(en)

1994-01-18

Control method and device of elevator

US4486824A
(en)

1984-12-04

PWM Converter with control circuit responsive to minimum holding current

KR840008456A
(en)

1984-12-15

Control device of AC elevator

JP2619390B2
(en)

1997-06-11

Induction motor speed control device

KR830001532B1
(en)

1983-08-08

AC motor drive control device

KR850002699Y1
(en)

1985-11-13

Speed control device in ac elevator

JPH10304669A
(en)

1998-11-13

Pwm converter device

SU888321A1
(en)

1981-12-07

Frequency converter for frequency-controllable electric drive

JPS6056785A
(en)

1985-04-02

Controller for speed of elevator

JPH0270292A
(en)

1990-03-09

Controller for inverter device

JPS60261384A
(en)

1985-12-24

Controller of ac motor

JPS58136277A
(en)

1983-08-13

Braking device for induction machine

JPS60237888A
(en)

1985-11-26

Controller of ac elevator

JPS59220076A
(en)

1984-12-11

Inverter

JPS60141193A
(en)

1985-07-26

Drive device of induction motor

JP2000166259A
(en)

2000-06-16

Control method for inverter device for drive of motor

JPH0670576A
(en)

1994-03-11

Controller for dc brushless motor

JPS62296796A
(en)

1987-12-24

Controller for motor driving inverter

Download PDF in English

None