Abstract:
A controller for a variable frequency drive monitors electrical power from a variable frequency drive motor while a brake is maintaining a load driven or moved by the motor without requiring additional feedback components of a closed loop configuration. If excess electrical power is being generated by the motor, an undesirable condition in the brake is indicated. Support or maintenance of the load is assumed by the motor in that event. Appropriate alarms or indicators are also activated.
Abstract:
A control system for a pneumatically operated mast has a first control, a second control, and a positioning member. A first serial link communicates the first control with the second control. A second serial link communicates the second control with the positioning member. A relay system communicates with the first and second control and the positioning member. The relay system accommodates a 12 voltage or 24 voltage source.
Abstract:
A method and apparatus for utilizing unused power available in an elevator that is not fully loaded to improve the traffic handling capacity of an elevator system (1). The present invention can be used to provide an optimized velocity profile for an elevator based on the pre-designed power of the drive motor (11) and the actual load in the elevator.The invention can achieve velocities higher than the design velocity of the elevator system (1). The method also utilizes surplus torque available to the motor (11) during a trip to produce an optimized velocity profile that has a short trip time, yet does not exceed the torque deliverable by the motor (11) and does not exceed acceptable discomfort levels to the passengers or the mechanical limitations on the system (1).
Abstract:
A method for intelligent control is disclosed including exchange of historical parameters of events for operating a system and operting a hoist (1) where an electric motor, preferably a DC-motor (11), is used for lifting and lowering a lifting belt (6). It can take place at different speeds by registering amperage through the motor and to perform a switching between fast and slow speed when a given current level (18) is reached. The change in hoisting/lowering speed is achieved when a control unit (13) changes the voltage suplied by the battery unit (12) to the DC-motor (11) or changes the frequency of power supply to an AC-motor. The method makes ti possible to control the system and to optimise the hoisting/lowering speed for the lifting belt depending on the load thereon.
Abstract:
The invention relates to a procedure for regulating the velocity of an elevator. In the procedure, the regulation of velocity employs feedback and is digitally implemented. The feedback for velocity regulation is effected using a feedback signal (Vest) which is generated from a reference (Tohje) controlling the elevator drive (4) and based on the result (Volo) of a measurement of the velocity of the elevator. The invention also relates to an elevator system in which the velocity data (Volo) produced by a velocity measuring device is used to generate a feedback signal (Vest) by using the parameters (β) of a model describing the operation of the elevator.
Abstract:
The invention relates to a drive system (100) for driving an electric motor (110). The drive system (1009) comprises a drive control unit (120) and a frequency converter (130) comprising a speed controller (140). The drive control unit (120) is configured to: define a speed reference (210) of the electric motor (110); preset operating parameters of the speed controller (140) to provide a first response time of the speed controller (140), before a drive of the electric motor (110) is initiated; adjust at least one operating parameter of the speed controller (140) to provide a second response time of the speed controller (140), after the speed of the electric motor (110) reaches a constant speed, wherein the second response time is slower than the first response time; and readjust the at least one operating parameter of the speed controller (140) to provide the first response time, before a deceleration from the constant speed is initiated. The invention relates also to a method for controlling the drive system (100) for driving the electric motor (110).
Abstract:
The invention is generally directed to an elevator display system which provides the illusion of observing a visual narrative of an elevator trip which is made to appear as if the actual elevator has glass walls and one is observing a fanciful elevator trip. The elevator can have a variety of different fanciful rides which are not restricted by the constraints of time, location or physics.