Controller of elevator

• US 20010017243A1
• Filed: 02/20/2001
• Published: 08/30/2001
• Est. Priority Date: 02/28/2000
• Status: Active Grant

• Current Assignee: Korea Electric Power Corporation (Government of South Korea), Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Korea Electric Power Corporation (Government of South Korea), Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Kobayashi, Kazuyuki, Araki, Hiroshi, Suga, Ikuro, Tajima, Shinobu
• Granted Patent: US 6,435,313 B2
• Time in Patent Office: Days
• 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

Abstract

This invention provides a controller of an elevator for stably controlling charging and discharging operations of a power accumulating device by using a cheap secondary battery of a low capacity, without damaging energy saving effects obtained by charging. Therefore, the controller of the elevator comprises a converter 2 for rectifying AC power and converting the AC power to DC power; an inverter 4 for converting the DC power to AC power of a variable voltage and a variable frequency to operate the elevator; a power accumulating device 11 for accumulating DC power from a DC bus 3 at a regenerative operation time of the elevator and supplying the DC power accumulated on the DC bus at a power running operation time; a charging-discharging control circuit 15 for controlling charging and discharging operations of the power accumulating device; a series connecting body, arranged between DC buses, and constructed by a gate 16 for regenerative current control and a regenerative resistor 17; a regenerative control circuit 19A for controlling an operation of the gate for regenerative current control; and a charging-discharging state measuring device 14A for measuring charging and discharging states of the power accumulating device. The charging-discharging control circuit 15A controls the charging and discharging operations of the power accumulating device in accordance with a measuring value of a bus voltage and a measuring value of the charging and discharging states.

Claims

1. A controller of an elevator comprising:

a converter for rectifying AC power from an AC power source and converting the AC power to DC power;

an inverter for converting the DC power to AC power of a variable voltage and a variable frequency and driving an electric motor and operating the elevator;

a power accumulating device arranged between DC buses between said converter and said inverter, and accumulating DC power from the DC buses at a regenerative operation time of the elevator and supplying the DC power accumulated on the DC buses at a power running operation time;

charging-discharging control means for controlling charging and discharging operations of said power accumulating device with respect to said DC buses;

bus voltage measuring means for measuring a bus voltage of each of said DC buses; and

charging-discharging state measuring means for measuring charging and discharging states of said power accumulating device;

said charging-discharging control means controlling the charging and discharging operations of said power accumulating device according to a measuring value from said bus voltage measuring means and a measuring value from said charging-discharging state measuring means.

2. A controller of an elevator according to

claim 1

, wherein

said charging-discharging control means has a table setting a limited charging current with respect to temperature, and the limited charging current corresponding to a measuring value of the temperature from said table calculated from said charging-discharging state measuring means on the basis of the measuring value of the temperature, and the charging current supplied to said power accumulating device is controlled on the basis of the comparison of a measuring value of the charging current from said charging-discharging state measuring means and the limited charging current.

3. A controller of an elevator according to

claim 2

, wherein

said charging-discharging control means has plural tables each according to a charging degree as a value obtained by normalizing and accumulating a product of a charging-discharging current and a charging-discharging voltage by a capacity with a full charging state of said power accumulating device as a reference, and selects a table according to said charging degree.

4. A controller of an elevator according to

claim 1

, wherein

said charging-discharging control means has a table in which a limited charging current is set with respect to a charging degree as a value obtained by normalizing and accumulating a product of a charging-discharging current and a charging-discharging voltage by a capacity with a full charging state of said power accumulating device as a reference, and said charging-discharging control means calculates the limited charging current corresponding to a value of the charging degree based on the measuring value from said charging-discharging state measuring means, and controls the charging current supplied to said power accumulating device on the basis of the comparison of a measuring value of the charging current and the limited charging current.

5. A controller of an elevator according to

claim 1

, wherein

said charging-discharging control means controls a charging current supplied to said power accumulating device on the basis of the comparison of a measuring value of the charging current from said charging-discharging state measuring means and a maximum charging current set value.

6. A controller of an elevator according to

claim 1

, wherein

said charging-discharging control circuit has a table setting a maximum charging voltage with respect to a charging current, and calculates a set value of the maximum charging voltage corresponding to a measuring value of the charging current from said charging-discharging state measuring means, and controls the charging current supplied to said power accumulating device on the basis of the comparison of a measuring value of the charging voltage and the set value of the maximum charging voltage.

7. A controller of an elevator according to

claim 1

, wherein

the controller further comprises speed control means for controlling a speed of the elevator by controlling an output voltage and an output frequency of said inverter, and said charging-discharging control means controls a discharging current of said power accumulating device on the basis of the measuring value from said bus voltage measuring means, the measuring value from said charging-discharging state measuring means, and speed commands from said speed control means.

8. A controller of an elevator according to

claim 1

, wherein

said charging-discharging control means has a table setting a limited discharging current with respect to temperature, and calculates the limited discharging current corresponding to a measuring value of the temperature from said charging-discharging state measuring means, and controls the discharging current supplied to said power accumulating device on the basis of the comparison of a measuring value of the discharging current and the limited discharging current.

9. A controller of an elevator according to

claim 8

, wherein

said charging-discharging control means has plural tables each according to a charging degree as a value obtained by normalizing and accumulating a product of a charging-discharging current and a charging-discharging voltage by a capacity with a full charging state of said power accumulating device as a reference, and selects a table according to the charging degree based on the measuring value from said charging-discharging state measuring means.

10. A controller of an elevator according to

claim 1

, wherein

said charging-discharging control means has a table in which a limited discharging current is set with respect to a charging degree as a value obtained by normalizing and accumulating a product of a charging-discharging current and a charging-discharging voltage by a capacity with a full charging state of said power accumulating device as a reference, and said charging-discharging control means calculates the limited discharging current corresponding to the value of the charging degree based on the measuring value from said charging-discharging state measuring means, and controls the discharging current supplied to said power accumulating device on the basis of the comparison of a measuring value of the discharging current and the limited discharging current.

11. A controller of an elevator according to

claim 1

, wherein

said charging-discharging control means has a table setting a maximum discharging voltage with respect to the discharging current, and calculates a set value of the maximum discharging voltage corresponding to a measuring value of the discharging current from said charging-discharging state measuring means, and controls the discharging current supplied to said power accumulating device on the basis of the comparison of a measuring value of the discharging voltage and the set value of the maximum discharging voltage.