The use of flange torque sensors HBM in the energy sector.
Steadily increasing global energy demand along with stricter requirements for enterprises of the energy sector on rational use of natural resources and environmental protection – all these factors necessitate the implementation of innovative technologies in the processes of operation of such enterprises.
Power and efficiency are the two key factors in the power plants. Efficiency is the ratio between the effective power of the generator produced per unit time, produced by power expressed in fuel volume.
The effective power is relatively easy to measure the output of the generator. Measurements required to assess the effectiveness of the entire system significantly more complex. Definition of mass fuel consumption is widely common method used for this purpose. However, direct measurement of mass flow is relatively inaccurate method because it does not take into account the impact on the measurement uncertainty of additional factors such as the type of fuel. In practice, the mass flow of fuel can be indirectly measured using certain calibration values and simulation programs.
Another method to determine the drive capacity is the measurement of the torque on the shaft between the actuator and the generator, on the basis of which the speed of rotation is computed drive power. This is achieved by measuring the elastic twisting of the input shaft formed by torque on the drive side. There are several similar methods is not direct, but indirect measure torque by measuring a parameter associated with a torque and subsequent calculation. The parameters that need to be considered in the calculation (e.g., material, geometry of the shaft) are subject to biases that invariably lead to relatively high errors of measurement of torque.
Measurement of the elastic twisting of the input shaft through the surface deformation is a good enough compromise. On the shaft surface bonded strain gages and connected in a measuring bridge. The excitation voltage of the measuring bridge and the measuring signal is transmitted from the stator to the rotating shaft and Vice versa in a contactless manner via the telemetry system. Depending on the quality of execution and the components used, this method provides a very accurate measurement of deformations. However, subsequently calculated torque value in this case is the estimated error of 35%, due to the previously mentioned tolerances parameters to be taken into account. This method has great advantages for example, the existing system can be equipped with such a solution. However, the resulting error in the measurement of the torque does not meet modern requirements for new power generating plants.
The error of the methods described above can be significantly reduced by using the calibration shaft or its parts directly for the parameter torque. Portion of the shaft to be calibrated, the calibration gradually degraded machine, defined by the values of torque and corresponding to each value of the output signal is measured and documented. Calibration can be performed directly on site, however, this can lead to problems due to the complex and time-consuming process load and local ambient conditions. Calibration in a calibration laboratory provides optimal conditions and high accuracy, but it requires a complex and, perhaps, shift the load snap to install products calibrated in the calibration machine. In addition, in some cases, it may simply not be calibrating machine, suitable to the size of the calibrated component or maximum torque.
