Elevator controller

• US 7,837,011 B2
• Filed: 03/17/2005
• Issued: 11/23/2010
• Est. Priority Date: 03/18/2004
• Status: Expired due to Fees

• Current Assignee: Toshiba Elevator Kabushiki Kaisha
• Original Assignee: Toshiba Elevator Kabushiki Kaisha
• Inventors: Takasaki, Kazuhiko, Monden, Yukitaka
• Primary Examiner(s): Benson; Walter
• Assistant Examiner(s): Chan; Kawing
• Application Number:
  US10/591,394
• Publication Number:
  US 20070137945A1
• Time in Patent Office: 2,077 Days
• Field of Search: 187/290, 187/296, 187/293
• US Class Current: 187/296
• CPC Class Codes: B66B 1/30 effective on driving gear , e.g. acting on power electronics, on inverter or rectifier controlled motor
• CPC Class Codes: B66B 1/308 with AC powered elevator drive
• CPC Class Codes: H02P 1/029 Restarting, e.g. after power failure
• CPC Class Codes: H02P 3/12 by short-circuit or resistive braking
• CPC Class Codes: H02P 3/14 by regenerative braking
• CPC Class Codes: Y02B 50/00 Energy efficient technologies in elevators, escalators and moving walkways, e.g. energy saving or recuperation technologies

Abstract

In addition to the construction of a typical elevator control device in which power generated during regenerative operation is dissipated by a resistance chopper (18), an elevator control device is newly provided with: an electric double layer capacitor (21) connected in parallel with the DC capacitor (3) that smoothes the DC ripple of the rectifier circuit (2) that rectifies the AC power of the AC power source (1) and having an electrostatic capacitance that is considerably larger than this DC capacitor; a voltage detection circuit (22) that detects the terminal voltage of this electric double layer capacitor; and a drive control unit (5) that uses a voltage in the vicinity of the rated voltage of the electric double layer capacitor as the operating voltage of resistance chopper and, when the terminal voltage detected by a voltage detection circuit reaches the voltage in the vicinity of the rated voltage of the electric double layer capacitor, operates and controls the resistance chopper.

Claims

1. An elevator control device comprising:

a rectifier circuit that converts an AC voltage from an AC power source to a DC voltage;

a DC capacitor that smoothes ripples of said DC voltage;

an inverter that converts a smoothed DC voltage to an AC voltage of variable voltage and variable frequency;

a motor that is driven by said AC voltage that is output from said inverter to raise or lower a passenger cage;

a resistance chopper that is connected in parallel with said DC capacitor; and

a drive control unit that controls said inverter or controlling said resistance chopper such that said AC voltage of variable voltage and variable frequency is output in accordance with a speed instruction;

an electric double layer capacitor having an electrostatic capacitance that is substantially larger than that of said DC capacitor and that is connected in parallel with said DC capacitor, and capable of accumulating substantially all of a regenerated power from said motor;

a voltage detection unit that detects a terminal voltage of said electric double layer capacitor, and

an initial charging circuit connected in series with said electric double layer capacitor, and said initial charging circuit including a switch and a resistance connected in parallel to each other,

said drive control unit employing a voltage in a vicinity of a rated voltage of a electric double layer capacitor as a drive voltage of a resistance chopper and operates and controls said resistance chopper when a terminal voltage detected by said voltage detection unit reaches a voltage in a vicinity of said rated voltage of said electric double layer capacitor, and

said drive control unit charging said electric double layer capacitor while restricting a current during current passage from said AC power source due to said resistance when said switch is turned off on commencement of current passage from said AC power source and that connects said electric double layer capacitor in parallel with said DC capacitor when said switch is turned on after a required time after commencement of passage of current by said AC power source.

2. The elevator control device according to claim 1, further comprising:

a switch connected in series with said electric double layer capacitor, that is turned on in response to an operating instruction from said drive control unit during normal operation and that isolates said electric double layer capacitor from said DC capacitor when operation is stopped.

3. The elevator control device according to claim 1, further comprising:

a current breaking circuit connected in series with said electric double layer capacitor and that breaks an inflow of excess current produced by a short-circuit fault of said DC capacitor or said inverter to said electric double layer capacitor.

4. The elevator control device according to claim 1, in which, when said inverter is below a prescribed switching frequency, said electric double layer capacitor substitutes for a voltage smoothing function of said DC capacitor by deletion of said DC capacitor;

and

when said terminal voltage that is detected by said voltage detection unit reaches the vicinity of said rated voltage of said electric double layer capacitor, a voltage in the vicinity of said rated voltage of said electric double layer capacitor constitutes said operating voltage of said resistance chopper.