A calculation method of braking torque for eddy current dynamometer using least square method based on assumption of cylindrical ring

For engineering applications, the existing method of calculating the braking torque is more complex. Furthermore, the calculation method depends on the internal structure parameters which are often difficult to obtain. Hence, the calculational method of braking torque using least square method based on assumption of cylindrical ring (CR-LS) is proposed in this paper. Referring to calculation methods of eddy current braking devices, The CR-LS assumes that the eddy current is distributed as a cylindrical ring with the same width as the tooth tip of the inductor. Eddy current values are worked out by conversion coefficient. With the employ of LS, unknown internal structure parameters of dynamometer in formula are fitted. It makes the formula use in industrial control with easy. By experimental verification, the formula obtained by CR-LS was simple and available, and calculation results had minor errors in contrast with output values of actual system. Therefore CR-LS can be applied in actual engineering calculations of dynamometer.