The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 27, 2002
Filed:
Feb. 08, 2001
Shinobu Tajima, Tokyo, JP;
Hiroshi Araki, Tokyo, JP;
Ikuro Suga, Tokyo, JP;
Kazuyuki Kobayashi, Tokyo, JP;
Other;
Abstract
A controller of an elevator for stably controlling regenerated power by using a cheap secondary battery of a low capacity without damaging energy saving effects obtained by charging. The controller of the elevator includes a converter for rectifying AC power and converting the AC power to DC power; an inverter for converting the DC power to AC power having a variable voltage and a variable frequency and operating the elevator; a power accumulating device for accumulating DC power from a DC bus in a regenerative operation of the elevator and supplying the DC power accumulated on the DC bus during a power operation time; a charging-discharging control circuit for controlling charging and discharging operations of the power accumulating device; a series connecting body arranged between DC buses and including a gate for regenerative current control and a regenerative resistor; a regenerative control circuit for controlling operation of the gate for regenerative current control; and a charging-discharging state measuring device for measuring charge and discharge states of the power accumulating device. The regenerative control circuit controls the operation of the gate for regenerative current control in control modes in which duty is different in accordance with a measured value of the charge and discharge states.