Elevator control device

• US 7,588,125 B2
• Filed: 11/14/2005
• Issued: 09/15/2009
• Est. Priority Date: 11/14/2005
• Status: Active Grant

• Current Assignee: Mitsubishi Electric Corporation
• Original Assignee: Mitsubishi Electric Corporation
• Inventors: Shibata, Masunori, Ueda, Takaharu, Sakai, Masaya
• Primary Examiner(s): SALATA, ANTHONY J
• Application Number:
  US11/573,699
• Publication Number:
  US 20080315802A1
• Time in Patent Office: 1,401 Days
• Field of Search: 187/247, 187/281, 187/284, 187289-293, 187/296, 187/297, 187/248, 187/277, 318798-815
• US Class Current: 187/293
• CPC Class Codes: B66B 1/285 with the use of a speed pattern generator
• CPC Class Codes: B66B 1/308 with AC powered elevator drive

Abstract

An elevator control device that drives a cage in a high-efficient speed pattern without using a load detector such as a conventional scale device. The elevator control device includes: a current detector for detecting a current that is supplied to a motor from an inverter; a speed detector for detecting a rotation speed of the motor; a speed pattern generator for generating an elevator speed pattern; a motor speed control device for controlling the speed so that a speed detection value follows a speed command value of the speed pattern; and a motor current control device for controlling a current that is supplied to the motor with respect to the inverter by using a current detection value and the speed detection value on the basis of the speed command value. The motor current control device has a duty detector for detecting a duty that is a ratio of an on-time of the inverter within a given sampling period, and the speed pattern generator changes the speed pattern of the motor based on a duty detection value detected by the duty detector.

Claims

1. An elevator control device, which causes a cage to be raised and lowered by a motor driven by an inverter, the cage being connected to one end of a rope having the other end connected to a counterweight through a sheave, the elevator control device comprising:

a current detector for detecting a current that is supplied to the motor from the inverter;

a speed detector for detecting the rotation speed of the motor;

speed pattern generating means for generating an elevator speed pattern;

a motor speed control device for controlling a speed so that a speed detection value from the speed detector follows a speed command value of the speed pattern from the speed pattern generating means; and

a motor current control device for controlling a current that is supplied to the motor with respect to the inverter by using a current detection value from the current detector and the speed detection value from the speed detector on the basis of the speed command value from the motor speed control device,

wherein the motor current control device has duty detecting means for detecting a duty that is a ratio of an on-time of the inverter within a given sampling period, and

wherein the speed pattern generating means changes the speed pattern of the motor on the basis of a duty detection value that is detected by the duty detecting means.

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

bus voltage detecting means for detecting a bus voltage that is applied to the inverter; and

voltage calculating means for calculating a voltage that is applied to the motor on the basis of a bus voltage detection value from the bus voltage detecting means and a duty detection value from the duty detecting means,

wherein the speed pattern generating means changes the speed pattern of the motor on the basis of the output of the voltage calculating means.

3. The elevator control device according to claim 1, further comprising target floor setting means for generating a command to move the cage of the elevator from a present floor to a target floor,

wherein the speed pattern generating means changes a magnitude of the acceleration of the speed pattern according to a movement distance to the target floor which is set by the target floor setting means.

7. The elevator control device according to claim 2, further comprising target floor setting means for generating a command to move the cage of the elevator from a present floor to a target floor,

wherein the speed pattern generating means changes a magnitude of the acceleration of the speed pattern according to a movement distance to the target floor which is set by the target floor setting means.

4. An elevator control device, which causes a cage to be raised and lowered by a motor driven by an inverter the cage being connected to one end of a rope having the other end connected to a counterweight through a sheave, the elevator control device comprising:

a current detector for detecting a current that is supplied to the motor from the inverter;

a speed detector for detecting a rotation speed of the motor;

speed pattern generating means for generating an elevator speed pattern;

a motor speed control device for controlling the speed so that a speed detection value from the speed detector follows a speed command value of the speed pattern from the speed patter generating means;

a motor current control device for controlling a current that is supplied to the motor with respect to the inverter by using a current detection value from the current detector and the speed detection value from the speed detector on the basis of the speed command value from the motor speed control device; and

voltage detecting means for calculating a voltage that is applied to the motor on the basis of the current detection value from the current detector and the speed detection value from the speed detector,

wherein the speed pattern generating means changes the speed pattern of the motor on the basis of the output of the voltage calculating means.

5. An elevator control device, which causes a cage to be raised and lowered by a motor driven by an inverter, the cage being connected to one end of a rope having the other end connected to a counterweight through a sheave, the elevator control device comprising:

a current detector for detecting a current that is supplied to the motor from the inverter;

a speed detector for detecting a rotation speed of the motor;

speed patter generating means for generating an elevator speed pattern;

a motor speed control device for controlling the speed so that a speed detection value from the speed detector follows a speed command value of the speed pattern from the speed pattern generating means; and

a motor current control device for controlling a current that is supplied to the motor with respect to the inverter by using a current detection value from the current detector and the speed detection value from the speed detector on the basis of the speed command value from the motor speed control device,

wherein the speed pattern generating means changes over the speed pattern to a constant speed travel in a case where a difference between the speed detection value from the speed detector and a speed pattern or a differential value of the difference exceeds a threshold value that is set in advance during acceleration of the cage.

6. An elevator control device, which causes a cage to be raised and lowered by a motor driven by an inverter the cage being connected to one end of a rope having the other end connected to a counterweight through a sheave, the elevator control device comprising:

a current detector for detecting a cu rent that is supplied to the motor from the inverter;

a speed detector for detecting a rotation speed of the motor;

speed patter generating-means for generating an elevator speed pattern;

a motor speed control device for controlling the speed so that a speed detection value from the speed detector follows a speed command value of the speed pattern from the speed pattern generating means; and

a motor current control device for controlling a current that is supplied to the motor with respect to the inverter by using a current detection value from the current detector and the speed detection value from the speed detector on the basis of the speed command value from the motor speed control device,

wherein the motor current control means outputs a control command to the speed pattern generating means so as to stop acceleration and change over the speed pattern to a constant speed travel in a case where a difference between the current detection value from the current detector and a current command value or a differential value of the difference exceeds a threshold value that is set in advance during the acceleration of the cage, and

wherein the speed pattern generating means changes over the speed pattern to the constant speed travel on the basis of a control command from the motor current control device.