The described techniques are directed to inductive torque sensors that implement independent target coil and pickup coil systems. By utilizing the various principles of inductive angle sensors, and as a result of the specific physical arrangement of target coils, the inductive torque sensor may independently obtain a rotational position (i.e., mechanical angle) of the rotatable input shaft via one pickup coil system, and a rotational position (i.e., mechanical angle) of the rotatable output shaft via another pickup coil system. Combiner circuitry is also provided to calculate the torsion angle using the signals induced in each of two separate pickup coil systems. By using different k-fold symmetry periodicities in the target coils with respect to the coil configurations, the inductive torque sensor advantageously reduces or eliminates mutual coupling between the different target coil systems and provide robustness to stray or external electromagnetic fields.

An arrangement (100) for specifying the pressure (64), produced by a pump (30) driven by an electric motor (31), includes a processor (116) which derives a target pressure value (62, 118) from an internal torque value (114) and a loss torque (108). The arrangement (100) further derives (112) the internal torque value (114) from a motor current value (110) and a motor constant k.sub.e.

An arrangement (100) for specifying the pressure (64), produced by a pump (30) driven by an electric motor (31), includes a processor (116) which derives a target pressure value (62, 118) from an internal torque value (114) and a loss torque (108). The arrangement (100) further derives (112) the internal torque value (114) from a motor current value (110) and a motor constant k.sub.e.

A preload inspection method for a bearing device for a vehicle wheel comprises: a first bearing preload value calculation step for calculating a first bearing preload value; a first rotating torque measurement step for measuring a first rotating torque; a caulking step for swaging the small-diameter stepped part to the inner ring; a second bearing preload value calculation step for calculating a second bearing preload value; a second rotational torque measurement step for measuring a second rotational torque; a third bearing preload value calculation step for calculating a third bearing preload value by adding, to the first bearing preload value, a preload change amount based on a differential torque between the first rotating torque and the second rotating torque; and a determination step for determining the suitability of the preload from the second bearing preload value and the third bearing preload value.

A preload inspection method for a bearing device for a vehicle wheel comprises: a first bearing preload value calculation step for calculating a first bearing preload value; a first rotating torque measurement step for measuring a first rotating torque; a caulking step for swaging the small-diameter stepped part to the inner ring; a second bearing preload value calculation step for calculating a second bearing preload value; a second rotational torque measurement step for measuring a second rotational torque; a third bearing preload value calculation step for calculating a third bearing preload value by adding, to the first bearing preload value, a preload change amount based on a differential torque between the first rotating torque and the second rotating torque; and a determination step for determining the suitability of the preload from the second bearing preload value and the third bearing preload value.

A method of determining torsional deformation in a drivetrain e.g. of a wind turbine. To provide a reliable and simple deformation assessment, the method comprises the step of generating a first signal representing first rotational speed of a low speed shaft, generating a second signal representing the second rotational speed of a high speed shaft, and determining torsional deformation based on changes in the ratio between the first and second signals.

A method of determining torsional deformation in a drivetrain e.g. of a wind turbine. To provide a reliable and simple deformation assessment, the method comprises the step of generating a first signal representing first rotational speed of a low speed shaft, generating a second signal representing the second rotational speed of a high speed shaft, and determining torsional deformation based on changes in the ratio between the first and second signals.

A shaft torque control device executes highly responsive shaft-torque control even when spring rigidity of a connection shaft connecting an engine and dynamometer varies, and has a feedback control system including a nominal plant imitating input-output characteristics of a test system, generalized plant having nominal plant; controller providing an input with use of outputs and variation term causing variation in the nominal plant on the basis of a variation transfer function. In the controller, setting is made to satisfy a design condition. Nominal plant is structured with a two-inertia system configured by connecting two inertia bodies via a shaft having spring rigidity equal to a predetermined nominal value set to be a lower limit value in an assumed variation range of spring rigidity of the connection shaft. The variation transfer function is a positive real function. Spring rigidity in the nominal plant Na increases from the nominal value.

In a test run, in order to easily provide a high-quality propulsion torque of a torque generator based on the partially low-quality measured variables available on the test bench, it is foreseen that an inner torque (M.sub.i) of the torque generator (D) is measured and based on the measured inner torque (M.sub.i), from an equation of motion, including the measured inner torque (M.sub.i), a dynamic torque (M.sub.dyn) and a shaft torque (M.sub.w) measured on the output shaft of the torque generator (D), a correction torque ({circumflex over (M)}.sub.cor) is estimated, and from the estimated correction torque ({circumflex over (M)}.sub.cor) and the measured inner torque (M.sub.i), the propulsion torque (M.sub.v) according to the relation M.sub.v={circumflex over (M)}.sub.cor+M.sub.i is computed.

In a test run, in order to easily provide a high-quality propulsion torque of a torque generator based on the partially low-quality measured variables available on the test bench, it is foreseen that an inner torque (M.sub.i) of the torque generator (D) is measured and based on the measured inner torque (M.sub.i), from an equation of motion, including the measured inner torque (M.sub.i), a dynamic torque (M.sub.dyn) and a shaft torque (M.sub.w) measured on the output shaft of the torque generator (D), a correction torque ({circumflex over (M)}.sub.cor) is estimated, and from the estimated correction torque ({circumflex over (M)}.sub.cor) and the measured inner torque (M.sub.i), the propulsion torque (M.sub.v) according to the relation M.sub.v={circumflex over (M)}.sub.cor+M.sub.i is computed.