Nlinear optimization dilemma of fitting the model to the frequency response
Nlinear optimization difficulty of fitting the model for the frequency response dataset. Different complicated number representations from the similar datasets of frequency response information are completely presented. All presented complicated number representations are compared within a simulation test repeated a single thousand instances at distinct beginning points. This permits for high-quality indicators of every single representation to be ready. A further novelty on the write-up is in bounding the NLS operating with frequency data to a precise array of frequencies from the excitation signal. A second constraint is added for the damping issue, soEnergies 2021, 14,4 ofits assumed range is from zero to one particular. The presented identification workflow is verified by simulation and a dataset in the laboratory setup. two. Frequency Model of Electric Drive with Multi-Resonant Mechanical Part The model in the discussed electric direct drive has an electric element and a mechanical portion. Inside the actual application, a permanent magnet synchronous motor (PMSM) was applied. The laboratory setup is presented in Figure 1. The electric component consisted of a 3-phase provide, a 3-phase rectifier, and a 3-phase inverter. The mechanical aspect consisted of metal plates directly mounted to the motor shaft. The laboratory setup permitted for the measurement of 3-phase currents i a , ib and ic , which are transformed to rotating coordinates iq and id Olesoxime Technical Information depending on the rotor electric position e , that is calculated from the measured motor position M multiplied by the amount of motor pole pairs equal to 12. Two proportional ntegral (PI) re f re f controllers have been used to track reference currents iq and id . Actuating signals are voltages in rotating coordinates vq and vd , transformed to 3-phase stationary coordinates v a , vb , and vc as an input to get a pulse-width modulation (PWM) inverter. The PWM switches v DC voltage with a frequency of 10 kHz. The time constants of your electric aspect had been considerably smaller than those on the mechanical portion and had restricted influence on the velocity and position from the mechanical component. In the present short article, the author focused around the identification of the mechanical portion using a identified CTTF model of a current closed loop responsible for torque generation. The velocity in the motor M was calculated from the motor angular position M as a 1st time derivative d = M , exactly where M is transform in t the motor angular position divided by modify in time t. The calculated velocity of motor d contained high-frequency noise, and, therefore, a lowpass digital filter with a cutoff of 500 Hz frequency was applied. A low-pass filter would be the first part of the digital filter shown within the diagram in Figure 1. The second part of the digital filter is a bandstop filter, tuned to attenuate resonance frequencies in feedback signal d . The Ziritaxestat Inhibitor output in the made use of filter f ,r was made use of as a feedback signal within the speed controller having a reference velocity of re f . The velocity with the load L isn’t readily available in the measurements. The mechanical portion was modeled as four CTTFs: H1,1 (s), H1,two (s), H2,1 (s), and H2,2 (s), where only one pair of input and output was measurable, with motor present iq (equivalent to motor torque TM ) and motor velocity M . The torque of load TL and also the velocity of load L weren’t measurable at the laboratory setup of direct drive. The model on the direct-drive mechanics is presented in Figure two, exactly where the existing constant kT = 17.5 Nm/A, delays cur = 300 , and sam = 200 are recognized. The.
