Position control method and apparatus for an elevator drive

Claim 1

A method for the distance control of a positioning drive having a cascade structure wherein, through specifying an appropriate jerk input value and by a threefold integration over the time of the same, the control of a desired distance value takes place as well as the control of desired values of velocity and acceleration which are directly generated to subordinated velocity and armature current control circuits for forwrd correction, comprising the following steps: a. defining a control distance which is the basis of a positioning drive as a standard control distance which can be influenced by interferences, and characterizing said standard control distance by a standardized set of values for the parameters of said control distance superimposed to which are parameter value changes caused by interferences; b. adjusting a cascade control by fourfold forward correction to said standardized set of values for the parameters of said standard control distance including forward correcting a velocity controller by a specified desired velocity value, a current controller by a specified desired jerk value, and a control unit by said specified desired velocity value; c. subdividing the interferences, which can have an effect on said standard control distance, into two classes, deterministic interferences which can be determined by a starting test and stochastic interferences which cannot be determined by a starting test; d. quantitatively detecting said deterministic interferences by a starting test in a starting phase of every travel, forming a compensation signal therefrom which completely compensates a corresponding distance control error which occurs over a remaining travel distance, and inputting said compensation signal to said current controller; e. inputting distance control errors caused by stochastic interferences, after a conclusion of the starting test, to an integrating amplifier which is connected to a distance controller for completely equalizing until the end of the travel all distance control errors still remaining after performing said steps a. through d.; and f. upon a restart after a stop outside a place of destination, temporarily increasing a corresponding residual one of said distance control errors.

Claim 2

A method for the distance control of a positioning drive having a cascade structure wherein, through specifying an appropriate jerk input value and by a threefold integration over the time of the same, the control of a desired distance value takes place as well as the control of desired values of velocity and acceleration which are directly generated to subordinated velocity and armature current control circuits for forwrd correction, comprising the following steps: a. defining a control distance which is the basis of a positioning drive as a standard control distance which can be influenced by interferences, and characterizing said standard control distance by a standardized set of values for the parameters of said control distance superimposed to which are parameter value changes caused by interferences; b. adjusting a cascade control by fourfold forward correction to said standardized set of values for the parameters of said standard control distance including forward correcting a velocity controller by a specified desired velocity value, a current controller by a specified desired jerk value, and a control unit by said specified desired velocity value; c. subdividing the interferences, which can have an effect on said standard control distance, into two classes, deterministic interferences which can be determined by a starting test and stochastic interferences which cannot be determined by a starting test; d. quantitatively detecting said deterministic interferences by a starting test in a starting phase of every travel, forming a compensation signal therefrom which completely compensates a corresponding distance control error which occurs over a remaining travel distance, and inputting said compensation signal to said current controller; e. inputting distance control errors caused by stochastic interferences, after a conclusion of the starting test, to an integrating amplifier which is connected to a distance controller for completely equalizing until the end of the travel all distance control errors still remaining after performing said steps a. through d.; and f. upon a restart after a stop outside a place of destination, temporarily increasing a corresponding residual one of said distance control errors.

Claim 10

A method for the distance control of a positioning drive in an elevator system having an electric motor for driving an elevator car in an elevator shaft to predetermined destinations comprising the steps of: a. defining a standard control distance, which can be influenced by interferences, by a standardized set of values for the parameters of an elevator system to be controlled; b. providing a cascade control including connected in series, a distance controller, a velocity controller, a current controller, and a control unit for generating armature current to an electric motor in the elevator system to be controlled; c. adjusting said cascade control by fourfold forward correction to said standardized set of values including inputting a desired velocity command signal to said velocity controller and to said control unit and inputting a desired jerk command signal to said current controller; d. subdividing said interferences into deterministic interferences which can be determined by a starting test and stochastic interference which cannot be determined by a starting test; e. detecting said deterministic interferences by a starting test in a starting phase of every travel of an elevator car in the elevator system, forming a compensation signal from said deterministic interferences, and inputting said compensation signal to said current controller; f. after a conclusion of said starting test, inputting distance control errors through an integrating amplifier to said distance controller for completely equalizing all distance control errors remaining after performing said steps a. through e.; and g. upon a restart after a stop of the elevator car outside of a place of destination, temporarily increasing a corresponding one of said distance control errors.

Claim 11

A method for the distance control of a positioning drive in an elevator system having an electric motor for driving an elevator car in an elevator shaft to predetermined destinations comprising the steps of: a. defining a standard control distance, which can be influenced by interferences, by a standardized set of values for the parameters of an elevator system to be controlled; b. providing a cascade control including connected in series, a distance controller, a velocity controller, a current controller, and a control unit for generating armature current to an electric motor in the elevator system to be controlled; c. adjusting said cascade control by fourfold forward correction to said standardized set of values including inputting a desired velocity command signal to said velocity controller and to said control unit and inputting a desired jerk command signal to said current controller; d. subdividing said interferences into deterministic interferences which can be determined by a starting test and stochastic interference which cannot be determined by a starting test; e. detecting said deterministic interferences by a starting test in a starting phase of every travel of an elevator car in the elevator system, forming a compensation signal from said deterministic interferences, and inputting said compensation signal to said current controller; f. after a conclusion of said starting test, inputting distance control errors through an integrating amplifier to said distance controller for completely equalizing all distance control errors remaining after performing said steps a. through e.; and g. upon a restart after a stop of the elevator car outside of a place of destination, temporarily increasing a corresponding one of said distance control errors.

Claim 13

An apparatus for controlling the position of an elevator car supported by a cable and driven by an electric motor comprising: a distance controller having an input and having an output connected to an input of a velocity controller, said velocity controller having an output connected to an input of a current controller, said current controller having an output connected to an input of a control unit, said control unit having an output for supplying current to an electric motor in an elevator system; a first summing point connected to a source of a desired distance command signal and a source of an actual distance signal and having an output connected to said distance controller input; a second summing point connected to a source of a desired velocity command signal, a source of an actual velocity signal and to said output of said distance controller and having an output connected to said velocity controller input; a third summing point connected to a source of a desired jerk command signal and a source of a desired acceleration command signal and having an output; a fourth summing point connected to said third summing point output, a source of an actual current signal and to said velocity controller output and having an output connected to said current controller input; a fifth summing point connected to said source of a desired velocity command signal and to said current controller output and having an output connected to said control unit input; a measuring means having an input connected to said first summing point output and responsive to deterministic interferences for generating a measurement value error signal at an output; a function generator having an input connected to said measuring means output for generating a compensation signal at an output connected to said third summing point; and a series connected integrating amplifier and switch connected in parallel with a proportional amplifier in said distance controller and an operating control for closing said switch for a short time at a restart after a stop of the elevator car.

Claim 14

An apparatus for controlling the position of an elevator car supported by a cable and driven by an electric motor comprising: a distance controller having an input and having an output connected to an input of a velocity controller, said velocity controller having an output connected to an input of a current controller, said current controller having an output connected to an input of a control unit, said control unit having an output for supplying current to an electric motor in an elevator system; a first summing point connected to a source of a desired distance command signal and a source of an actual distance signal and having an output connected to said distance controller input; a second summing point connected to a source of a desired velocity command signal, a source of an actual velocity signal and to said output of said distance controller and having an output connected to said velocity controller input; a third summing point connected to a source of a desired jerk command signal and a source of a desired acceleration command signal and having an output; a fourth summing point connected to said third summing point output, a source of an actual current signal and to said velocity controller output and having an output connected to said current controller input; a fifth summing point connected to said source of a desired velocity command signal and to said current controller output and having an output connected to said control unit input; a measuring means having an input connected to said first summing point output and responsive to deterministic interferences for generating a measurement value error signal at an output; a function generator having an input connected to said measuring means output for generating a compensation signal at an output connected to said third summing point; and a series connected integrating amplifier and switch connected in parallel with a proportional amplifier in said distance controller and an operating control for closing said switch for a short time at a restart after a stop of the elevator car.