Abstract: An example includes: receiving a process variable; predicting a estimation value by linear fitting on a number of recent values, comparing that with a warning threshold, and if greater, setting the estimation value as a first value; comparing the current value with a value at the same position in the previous cycle to determine a deviation value, adding the deviation value to the previous peak value or trough value to serve as a maximum estimation value, comparing the maximum value with the preset warning threshold, and if greater, setting the maximum value as a second estimation value; computing a estimation value on the basis of the first and the second estimation; comparing the process variable estimation value with the preset warning threshold; and issuing an early alert signal if the estimation value is greater than the threshold.

Abstract: A method, apparatus and system are for displaying measurement information. An embodiment of the method includes: obtaining a display instruction for displaying measurement information of at least one second transmitter; and displaying, after obtaining the display instruction, the measurement information of the at least one second transmitter on a display screen of the a first transmitter. The first transmitter and the at least one second transmitter perform data communication with a distributed I/O device according to a preconfigured data transmission path. Further, the measurement information of the at least one second transmitter is obtained by means of the distributed I/O device according to the preconfigured data transmission path. The embodiment of the method enables an operator to conveniently view the measurement information of the second transmitter on the first transmitter nearby, without viewing the information on a remote device manager or the second transmitter.

Abstract: A method, apparatus and system are for displaying measurement information. An embodiment of the method includes: obtaining a display instruction for displaying measurement information of at least one second transmitter; and displaying, after obtaining the display instruction, the measurement information of the at least one second transmitter on a display screen of the a first transmitter. The first transmitter and the at least one second transmitter perform data communication with a distributed I/O device according to a preconfigured data transmission path. Further, the measurement information of the at least one second transmitter is obtained by means of the distributed I/O device according to the preconfigured data transmission path. The embodiment of the method enables an operator to conveniently view the measurement information of the second transmitter on the first transmitter nearby, without viewing the information on a remote device manager or the second transmitter.

Abstract: A wind turbine condition monitoring method includes the steps of generating in advance a reference curve for normal operation of a transmission chain of a wind turbine using position information, measuring position information and generating an actual condition monitoring curve; comparing the actual condition monitoring curve with the reference curve, and determining the current condition of the wind turbine from the comparison. With the proposed monitoring method, monitoring with a high signal-to-noise ratio can be achieved with minimal or no addition of hardware, such as an A/D module; moreover, computational task is greatly reduced, so that the monitoring system can be more easily integrated into the main control system. In addition, the position measurement system is more stable than a vibration measurement system, and the monitoring result is more reliable.

Abstract: A method and fault detection device for detecting faults in digital output channels includes a detection circuit for detecting a first level of a first detection point disposed before a switch and a load in the PLC system, detecting a second level of a second detection point disposed after the switch and load in the PLC system, and for outputting a corresponding first pulse signal according to a change in the first level and second levels, a judgment circuit for judging whether the pulse width of the received first pulse signal is within a permitted range and for outputting a second pulse signal when the judgment result is negative, a trigger circuit for triggering the display circuit according to the received second pulse signal, and a display circuit for displaying a detection result in response to a received signal.

Abstract: A wind turbine condition monitoring method includes the steps of generating in advance a reference curve for normal operation of a transmission chain of a wind turbine using position information, measuring position information and generating an actual condition monitoring curve; comparing the actual condition monitoring curve with the reference curve, and determining the current condition of the wind turbine from the comparison. With the proposed monitoring method, monitoring with a high signal-to-noise ratio can be achieved with minimal or no addition of hardware, such as an ND module; moreover, computational task is greatly reduced, so that the monitoring system can be more easily integrated into the main control system. In addition, the position measurement system is more stable than a vibration measurement system, and the monitoring result is more reliable.

Abstract: A method and an apparatus for quantitatively detecting the unbalanced state of a rotating shaft and a clamping state of a workpiece clamped to a shaft are disclosed by solving with a nonlinear multivariable method a Lagrange kinematics equation to determine from acquired position, velocity, acceleration and torque signals of the rotating shaft an unbalanced amplitude variable and an unbalanced angle variable of the rotating shaft, optionally both with and without a workpiece. The motor driving the shaft is energized with a combined S-shaped and sinusoidal velocity profile with a position profile component, a velocity profile component, and an acceleration profile component. The components are selected such that the motor speed during the accelerating and decelerating stages does not change abruptly.

Abstract: A method and an apparatus for quantitatively detecting the unbalanced state of a rotating shaft and a clamping state of a workpiece clamped to a shaft are disclosed by solving with a nonlinear multivariable method a Lagrange kinematics equation to determine from acquired position, velocity, acceleration and torque signals of the rotating shaft an unbalanced amplitude variable and an unbalanced angle variable of the rotating shaft, optionally both with and without a workpiece. The motor driving the shaft is energized with a combined S-shaped and sinusoidal velocity profile with a position profile component, a velocity profile component, and an acceleration profile component. The components are selected such that the motor speed during the accelerating and decelerating stages does not change abruptly.