The subject matter of this specification can be embodied in, among other things, a controller apparatus that includes a digital controller configured to provide a digital position signal based on a setpoint and a differential analog feedback signal, and a converter circuit configured to provide a differential analog electrohydraulic servo valve position control signal based on the digital position signal, and provide the differential analog feedback signal based on the differential analog electrohydraulic servo valve position control signal.

In order to carry out largely automated parameterisation of the closed-loop control parameters for closed-loop control of a hydraulic system comprising a servo drive, a method and a device for determining the closed-loop parameters of a closed-loop control unit of the hydraulic system are specified, wherein an actual system pressure of a hydraulic consumer of the hydraulic system is closed-loop controlled by means of a predefined set point rotational speed of a servo drive, wherein an actual rotational speed of the servo drive follows the predefined set point rotational speed, wherein an excitation signal is applied to the setpoint rotational speed, and the actual system pressure which is set here is measured, the dynamics of the hydraulic system are acquired from the actual rotational speed and/or the setpoint rotational speed and the actual system pressure, and the closed-loop control parameters are calculated from the acquired dynamics.

A diagnostic apparatus determines, at a reference time, whether a device is normal or abnormal, and in which operation state the device is at the time. A reference data creation unit repeats a process of storing sensor values acquired from the device while changing the operation state at the reference time in association with each of the determined operation states until there is no non-corresponding operation state with which the acquired sensor value is not yet associated. At a diagnosis time at which it is not known whether the device is normal or abnormal, an operation state and a sensor value of the device at the time is acquired. The stored sensor value associated with the acquired operation state is read to compare the sensor value acquired at the diagnosis time with the read sensor value to display a result of determination on whether the device is normal or abnormal.

The subject matter of this specification can be embodied in, among other things, a controller apparatus that includes a digital controller configured to provide a digital position signal based on a setpoint and a differential analog feedback signal, and a converter circuit configured to provide a differential analog electrohydraulic servo valve position control signal based on the digital position signal, and provide the differential analog feedback signal based on the differential analog electrohydraulic servo valve position control signal.

A control device that controls an electric hoisting machine includes: a tension sensor that detects tension of a pulling member; a mode input unit that inputs a mode switch signal to switch between a winding mode and an unwinding mode; and a control unit that controls the operation of a electric motor. The control unit, when set in the unwinding mode, controls the electric motor in accordance with a detection signal from the tension sensor to cause the rotating body to be inversely rotated when the tension of the pulling member is not less than a predetermined threshold value, and to prevent the rotating body from being inversely rotated when the tension of the pulling member is lower than the predetermined threshold value.

A control device that controls an electric hoisting machine includes: a tension sensor that detects tension of a pulling member; a mode input unit that inputs a mode switch signal to switch between a winding mode and an unwinding mode; and a control unit that controls the operation of a electric motor. The control unit, when set in the unwinding mode, controls the electric motor in accordance with a detection signal from the tension sensor to cause the rotating body to be inversely rotated when the tension of the pulling member is not less than a predetermined threshold value, and to prevent the rotating body from being inversely rotated when the tension of the pulling member is lower than the predetermined threshold value.

In order to carry out largely automated parameterisation of the closed-loop control parameters for closed-loop control of a hydraulic system comprising a servo drive, a method and a device for determining the closed-loop parameters of a closed-loop control unit of the hydraulic system are specified, wherein an actual system pressure of a hydraulic consumer of the hydraulic system is closed-loop controlled by means of a predefined set point rotational speed of a servo drive, wherein an actual rotational speed of the servo drive follows the predefined set point rotational speed, wherein an excitation signal is applied to the setpoint rotational speed, and the actual system pressure which is set here is measured, the dynamics of the hydraulic system are acquired from the actual rotational speed and/or the setpoint rotational speed and the actual system pressure, and the closed-loop control parameters are calculated from the acquired dynamics.

In one aspect, a wireless transceiver is used to wirelessly connect various electrohydraulic components in a hydraulic system. In another aspect, a self-powered wireless hydraulic system includes a harvesting device for converting hydraulic energy into electrical energy. The electrical energy generated by the harvesting device can be used to power one or more electrohydraulic components and wireless transceivers. In another aspect, a self-powered wireless hydraulic system also includes a flow control device powered by the harvesting device for actively controlling the hydraulic flow through the harvesting device.

A method for operating a winch and an electric drive for driving a winch including a rotatable winch drum for spooling a spoolable medium and an electric motor operably coupled to the winch drum, the electric drive being configured to drive the winch drum by driving the electric motor such that a tension of the spoolable medium reaches a predetermined tension set point value or value range, and set a driving speed of the electric motor to zero, and after the setting of the driving speed of the electric motor to zero, drive the electric motor to alternate directions of rotation at predetermined driving speeds such that the direction of rotation is changed at a predetermined frequency.

In one aspect, a wireless transceiver is used to wirelessly connect various electrohydraulic components in a hydraulic system. In another aspect, a self-powered wireless hydraulic system includes a harvesting device for converting hydraulic energy into electrical energy. The electrical energy generated by the harvesting device can be used to power one or more electrohydraulic components and wireless transceivers. In another aspect, a self-powered wireless hydraulic system also includes a flow control device powered by the harvesting device for actively controlling the hydraulic flow through the harvesting device.