A way to obtain the rotor flux angle is to calculate the rotor flux linkage from the air-gap flux detected by Hall effect sensors or sensing coils, which are installed in the applied motor. However, this method is costly and is not practical. A widely used method is to estimate the ...
The amount of back-EMF is once calculated through the reference model em (17), and the other time, by the adjustable model êm (17). The error between these two values converges to zero through the adaptive mechanism. This method is robust to Rs variations but any error in the Rr ...
Ok, here we go. In a rotating mechanism (helicopter rotor), at a state of equilibrium, the rotor consumes a certain amount of energy from the shaft to maintain a constant angular velocity (since there is a measure of resistance present over the span of the rotor). Lets suppose that the...
Inthiscontextadecisionmapisafunction:01→{−101}which ‘decides’whetheravariablehastobedecreased,keptconstant,orincreasedtheerrorispracticallyzero,duetolargejumpsinthecontrol dependingonwhetheritsvalueis−1,0,or1,respectively.command.Eventhoughgeneratingchatteringforavery 5205 OperationInstructionsClockcyclesTime...
an endless belt and a motor controller. The outer rotor motor drives the belt at commanded speeds. The outer rotor motor is preferably a brushless permanent magnet motor with a sinusoidal back EMF waveform, and the controller can be a sine wave drive based on field orientation control algorithms...
It is equally clear that because the rotor cage comprises permanently short-circuited conductor bars, no external control can be exercised over the resistance of the rotor circuit once the rotor has been made. This is a significant drawback which can be avoided in the second type of rotor, ...
The flux linkage waveforms of BEESM1 and BEESM2 when the excitation current is 10 A are shown in Fig. 8. It can be seen that the amplitude of the waveforms of BEESM1 is larger than that of the BEESM2. The phase back-EMF of BEESMs can be calculated as (9)ephase=dφphase∕dt....
Hence, it is only suitable for PMSMs with sinusoidal back EMF, and its application scenarios are limited. Similarly, it was concluded in [29] that the derivative of the d-axis current harmonics will be the major error in the estimation of VSI nonlinearity. Moreover, the suppression of d-...
However, the estimation of the back-EMF under low speed is quite complex; combining this method with a normal HFI method in position sensorless control, the program should be switched between the two methods. A simpler method was proposed in [20], in which a current ramp was imposed on ...
magnet-less machines are being widely regarded as potential alternatives. The permanent magnet vernier machine is a good candidate for EVs as it produces almost double the back EMF compared to conventional permanent magnet synchronous machines. A wound field pole changing vernier machine with a fractio...