A differential electromagnetic induction torque sensor and its finite element analysis

Abstract

Torque is an important parameter for condition monitoring and fault diagnosis for rotary machines. This paper describes a new structure differential torque sensor based on the principle of electromagnetic induction. The method involves the construction of a pulsating flux by the excitation winding of the sensor, and the torsion angle produced by the load torque is converted into the angle displacements of the excitation winding and the output winding. Last, the output winding of sensor generates an induction potential force, which is proportional to the load torque as seen through electromagnetic coupling. Sensor sensitivity would be reduced by load effect; therefore, this paper presents a suppression method that can ensure the sensitivity is not affected. The transfer function of the sensor is constructed through Laplace transformation. The sensor characteristics are simulated by finite elements, including the influence of winding coil numbers and excitation voltage frequency. The sensor was calibrated by a torsion testing machine, and the experimental results indicated that the sensitivity of the sensor is about 18.2 mV/Nm, the non-repeatability error is about 2.3%, the non-linear error is about 3.3%, and the hysteresis error is about 2.6%.

Analysis and Optimization of Planar Excitation Coil for EPS Torque Senor Based on GWO

“…When the circuit produces resonance, the power supply angular frequency is 𝜔 = (𝐿𝐶) 1/2 = 2𝜋𝑓, and the equivalent model circuit is resistive. Combining with equation ( 1), the excitation coil input power 𝑃 𝑖𝑛 and receiver coil output voltage 𝑉 𝑒𝑐𝑒 can be obtained, as shown in equation (3).…”

“…Due to space constraints, the excitation coil, as an important component of the torque sensor, should meet the design requirements of large inductance, small size, low-cost, high-quality factor, easy integration, and mass production. At present, the eddy current effect and the electromagnetic induction coupling principle are widely used in measurement systems [2,3]. However, the excitation coil is less analysed and further research is needed.…”

Sleeve-type Torque Sensor Based on Effect of Strain Induction Applied to Wide-blade Drill Rod

“…Furthermore, the contact type between the torque sensor and the drill rod is set to "friction", and that between the torque sensor and the strain gauges is set to "binding". As for mesh generation, (11,12) a tetrahedral mesh is adopted, and the mesh on the friction surface is generated densely to improve the analysis accuracy.…”

Non-destructive diagnosis of grounding grids based on the electromagnetic induction impedance method

“…This method can detect global damage rather than local corrosion of the grid. There are three state-of-the-art local detection methods for the diagnosis of corroded points, including the soil resistivity method [7], the transient electromagnetic (TEM) method [8] and the electromagnetic induction (EMI) method [9,10].…”