Abstract: A method for determining an efficiency and/or calibrating a torque of a drivetrain comprises two tests. The drivetrain has a motor-side end at a main shaft connectable to a motor and a generator-side end, with a generator arranged between the ends. In a first test, the motor-side end of the drivetrain is driven. A variable dependent on the main shaft torque is determined at the motor-side end of the drivetrain and an electrical power Pelec is determined at the generator-side end of the drivetrain. In a second test, the generator-side end of the drivetrain is driven and the variable dependent on the main shaft torque is determined at the motor-side end and the electrical power is determined at the generator-side end. An efficiency and/or calibration parameters is/are determined from the electrical power values and the variables dependent on the main shaft torque determined in the first test and second tests.

Abstract: A method and a device for measuring the torque in the drivetrain (1) of a wind power plant is described, having at least two incremental encoders (7, 8) which are positioned at two different positions on at least one shaft (3) of the drivetrain (1) and which each supply periodic rotational signals, wherein the phases of the rotational signals are evaluated in order to detect a phase shift, and a torque of the shaft (1) is determined from the phase shift. The detected phase shift is corrected as a function of a zero load phase shift (AZero), using a rigidity factor K, wherein, in order to determine the zero load phase shift (AZero) and the rigidity factor K, in-situ calibration is carried out before and/or between the torque-determining processes. The in-situ calibration is performed at zero load of the wind power plant, i.e. below a rated rotational speed and with a generator torque equal to zero, and at the rated load of the wind power plant, i.e.

Abstract: A method and a device for measuring the torque in the drivetrain (1) of a wind power plant is described, having at least two incremental encoders (7, 8) which are positioned at two different positions on at least one shaft (3) of the drivetrain (1) and which each supply periodic rotational signals, wherein the phases of the rotational signals are evaluated in order to detect a phase shift, and a torque of the shaft (1) is determined from the phase shift. The detected phase shift is corrected as a function of a zero load phase shift (AZero), using a rigidity factor K, wherein, in order to determine the zero load phase shift (AZero) and the rigidity factor K, in-situ calibration is carried out before and/or between the torque-determining processes. The in-situ calibration is performed at zero load of the wind power plant, i.e. below a rated rotational speed and with a generator torque equal to zero, and at the rated load of the wind power plant, i.e.

Abstract: The present application relates to a method for determining an efficiency and/or for calibrating a torque of a drivetrain (1), in particular a drivetrain (1) of a wind turbine. The method for determining an efficiency and/or for calibrating a torque of a drivetrain (1), in particular of a drivetrain of a wind turbine, is particularly suited for carrying out on a test rig and comprises two tests. The drivetrain has a motor-side end at a main shaft connectable to a motor and a generator-side end, between which ends a generator is arranged. In a first test, the motor-side end of the drivetrain (1) is driven. A variable dependent on the main shaft torque is thereby determined at the motor-side end of the drivetrain (1) and an electrical power Pelec is determined at the generator-side end of the drivetrain (1).

Abstract: The device serves for cooling electronic structural elements and has a cooling body and a metal base plate constructed as a part of the support of the structural element. The cooling body is arranged adjacent the base plate. A connecting element is arranged at least over areas between the base plate and the cooling body. The connecting element is at least partially constructed of a metal which has a melting temperature of at least 60° C. The connecting element is provided with a frame-like seal.

Abstract: A method and an apparatus for measuring electric currents include at least one sensor for measuring the magnitude of the field strength depending on the current. The current to be measured is conducted past the sensor at least partially with oppositely directed directional components at the sensor. At least one magnetic field sensor can be used as a sensor.