Elevator controller

• US 20040035646A1
• Filed: 03/18/2003
• Published: 02/26/2004
• Est. Priority Date: 10/17/2001
• Status: Active Grant

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Araki, Hiroshi
• Granted Patent: US 6,827,182 B2
• Time in Patent Office: Days
• US Class Current: 187/290
• CPC Class Codes: B66B 5/02 responsive to abnormal operating conditions
• CPC Class Codes: B66B 5/027 to permit passengers to leave an elevator car in case of failure, e.g. moving the car to a reference floor or unlocking the door

Abstract

The object of the present invention to obtain an elevator control apparatus which is capable of, when a power failure of the A.C. power source is detected, using effectively and usefully a quantity of charged power in a power accumulator and when recovering the power supply, returning an elevator back to the original service to make the proper operation possible. The control system is provided with control means for, when a power failure is detected with a power failure detector, supplying the power of the power accumulator to an inverter and to control circuits and an illumination circuit of the elevator with a charge/discharge control circuit to continue the operation of the elevator.

Claims

1. An elevator control apparatus, comprising:

a converter for converting an A.C. power from an A.C. power source into a D.C. power through rectification;

an inverter for converting the D.C. power from the converter into an A.C. power of a variable voltage and a variable frequency to drive an electric motor to operate the elevator;

a power accumulator provided across D.C. buses between the converter and the inverter for accumulating therein a D.C. power from the D.C. buses in a regenerative operation of the elevator to supply the D.C. power accumulated in a powering operation to the D.C. buses;

a charge/discharge control circuit for controlling the charge/discharge of the power accumulator for the D.C. buses;

a charging/discharging state measuring circuit for measuring a quantity of charged power or a charging/discharging state of the power accumulator;

a power failure detector for detecting a power failure of the A.C. power source;

a control power supply device for supplying the power to the elevator control apparatus during a power failure;

an illumination power supply apparatus for supplying the power to an illumination circuit of the elevator during a power failure; and

control means for, when a power failure is detected with the power failure detector, supplying the power of the power accumulator to the inverter and supplying the power to control circuits and the illumination circuit of the elevator with the charge/discharge control circuit to continue the operation of the elevator.

2. An elevator control apparatus according to claim 1, characterized in that the control means, when a power failure is detected, limits speed of the elevator.

3. An elevator control apparatus according to claim 1, characterized in that the control means, when a power failure is detected, selectively cuts off the illumination circuit of the elevator to limit the power supply in order to secure only the necessary illumination and cut off a cable way to unnecessary illumination.

4. An elevator control apparatus according to claim 1, characterized in that the control means, when a power failure is detected, selectively cuts off the control circuits of the elevator in order to secure only the control circuits of the control circuits required for the operation and cut off a cable way to the unnecessary control circuits.

5. An elevator control apparatus according to claim 1, characterized in that the control means, after a power failure is detected, when the operation of the elevator is being continued, if a measured value obtained with the charging/discharging state measuring circuit has become equal to or smaller than a set value, or a predetermined period of time has elapsed, stops the operation of the elevator.

6. An elevator control apparatus according to claim 5, characterized in that the control means informs a passenger that the operation of the elevator will be stopped.

7. An elevator control apparatus according to claim 2, further comprising a power supply recovery detector for detecting power source recovery of the A.C. power source, characterized in that the control means, when power supply recovery is detected, returns speed of the elevator back to the original rated speed.

8. An elevator control apparatus according to claim 7, characterized in that the control means, when power supply recovery is detected, after the elevator is stopped if the elevator is being moved, returns the operation of the elevator from an operation mode at the time of a power failure to the normal operation mode to return speed thereof back to the original rated speed.

9. An elevator control apparatus according to claim 3 or 4, further comprising a power supply recovery detector for detecting power supply recovery of the A.C. power source, characterized in that the control means, when power supply recovery is detected, connects the control circuits or the illumination circuit which has been selectively cut off.

10. An elevator control apparatus according to claim 1, characterized in that said control means is provided with both a continuous operation mode at the time of a power failure at which the operation of the elevator is continued, and a rescue operation mode at which the elevator is moved at low speed to be stopped at the nearest floor, and the control means selects the operation mode on the basis of a measured value obtained with the charging/discharging state measuring circuit or a lapse of a predetermined period of time from a power failure.

11. An elevator control apparatus according to claim 10, characterized in that the control means selects the rescue operation mode on the basis of the measured value obtained with the charging/discharging state measuring circuit or a lapse of a predetermined period of time from a power failure to prevent the passenger from being shut in the elevator due to the insufficiency in quantity of charged power in the power accumulator.

12. An elevator control apparatus according to claim 10, characterized in that the control means, when the measured value obtained with the charging/discharging state measuring circuit becomes equal to or smaller than a first set value, or when a lapse of time from a power failure becomes equal to or larger than the first set value, does not receive the hall call so as not to allow getting-in of a new passenger and to carry out the service for the car call by the passengers who is currently on board and when the measured value obtained with the charging/discharging state measuring circuit becomes equal to or smaller than a second set value, or when a lapse of time from a power failure becomes equal to or larger than the second set value, selects the rescue operation mode to prevent the passenger from being shut in the elevator due to insufficiency in quantity of charged power in the power accumulator.

13. An elevator control apparatus according to claim 12, characterized in that the second set value of the quantity of charged power is equal to or smaller than the first set value, and the second set value for the elapsed time from a power failure is equal to or larger than the first set value.