DIN EN 301140-4-2:2001-09, Intelligente Netze (IN)_- Anwendungsprotokoll für Intelligente Netze (INAP); Leistungsmerkmal Gruppe_2 (CS2)_- Teil_4: Abstrakte Prüfanweisung (ATS) und zu vervollständigendes Formular für Zusatzinformationen zur Prüfung der Protokollimplementierung (PIXIT) für die Service Switching Function (SSF); Teil_4-2: Verbindungssteuerung (CPH) (Anerkennung der Englischen Fassung EN_301140-4-2_V_1.1.3 (2000-05) als Deutsche Norm)

The six-phase motor control system has low torque ripple, low harmonic content, and high reliability; therefore, it is suitable for electric vehicles, aerospace, and other applications requiring high power output and reliability. This study presents a superior sensorless control system for a six-phase permanent magnet synchronous motor (PMSM). The mathematical model of a PMSM in a stationary coordinate system is presented. The information of motor speed and position is obtained by using a sliding mode observer (SMO). As torque ripple and harmonic components affect the back electromotive force (BEMF) estimated value through the traditional SMO, the function of the frequency-variable tracker of the stator current (FVTSC) is used instead of the traditional switching function. By improving the SMO method, the BEMF is estimated independently, and its precision is maintained under startup or variable-speed states. In order to improve the estimation accuracy and resistance ability of the observer, the rotor position error was taken as the disturbance term, and the third-order extended state observer (ESO) was constructed to estimate the rotational speed and rotor position through the motor mechanical motion equation. Finally, the effectiveness of the method is verified by simulation and experiment results. The proposed control strategy can effectively improve the dynamic and static performance of PMSM.

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The Approximation of the Nonlinear Singular System with Impulses and Sliding Mode Control via a Singular Polynomial Fuzzy Model Approach

Symmetry ◽

10.3390/sym13081409 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1409

Author(s):

Jiawen Li ◽

Yi Zhang ◽

Zhenghong Jin

Keyword(s):

Sliding Mode Control ◽

Sliding Mode ◽

Singular System ◽

Fuzzy Model ◽

Switching Function ◽

Covering Theorem ◽

Function Type ◽

Numerical Examples ◽

Mode Control ◽

Nonlinear Singular System

In this paper, the Singular-Polynomial-Fuzzy-Model (SPFM) approach problem and impulse elimination are investigated based on sliding mode control for a class of nonlinear singular system (NSS) with impulses. Considering two numerical examples, the SPFM of the nonlinear singular system is calculated based on the compound function type and simple function type. According to the solvability and the steps of two numerical examples, the method of solving the SPFM form of the nonlinear singular system with (and without) impulse are extended to the more general case. By using the Heine–Borel finite covering theorem, it is proven that a class of nonlinear singular systems with bounded impulse-free item (BIFI) properties and separable impulse item (SII) properties can be approximated by SPFM with arbitrary accuracy. The linear switching function and sliding mode control law are designed to be applied to the impulse elimination of SPFM. Compared with some published works, a human posture inverted pendulum model example and Example 3.2 demonstrate that the approximation error is small enough and that both algorithms are effective. Example 3.3 is to illustrate that sliding mode control can effectively eliminate impulses of SPFM.

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Generating high-dimensional grid multi-scroll attractors via feedback controller and switching function

2015 Chinese Automation Congress (CAC) ◽

10.1109/cac.2015.7382849 ◽

2015 ◽

Author(s):

Nan Yu ◽

Jiang-Wen Xiao ◽

Yan-Wu Wang

Keyword(s):

Feedback Controller ◽

High Dimensional ◽

Switching Function

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Role of Autocleavage in the Function of a Type III Secretion Specificity Switch Protein in Salmonella enterica Serovar Typhimurium

mBio ◽

10.1128/mbio.01459-15 ◽

2015 ◽

Vol 6 (5) ◽

Cited By ~ 31

Author(s):

Julia V. Monjarás Feria ◽

Matthew D. Lefebre ◽

York-Dieter Stierhof ◽

Jorge E. Galán ◽

Samuel Wagner

Keyword(s):

Host Cell ◽

Type Iii Secretion ◽

Effector Proteins ◽

Switching Function ◽

Gram Negative Bacteria ◽

Wild Type ◽

Gram Negative ◽

Type Iii ◽

Autocatalytic Cleavage ◽

Serovar Typhimurium

ABSTRACTType III secretion systems (T3SSs) are multiprotein machines employed by many Gram-negative bacteria to inject bacterial effector proteins into eukaryotic host cells to promote bacterial survival and colonization. The core unit of T3SSs is the needle complex, a supramolecular structure that mediates the passage of the secreted proteins through the bacterial envelope. A distinct feature of the T3SS is that protein export occurs in a strictly hierarchical manner in which proteins destined to form the needle complex filament and associated structures are secreted first, followed by the secretion of effectors and the proteins that will facilitate their translocation through the target host cell membrane. The secretion hierarchy is established by complex mechanisms that involve several T3SS-associated components, including the “switch protein,” a highly conserved, inner membrane protease that undergoes autocatalytic cleavage. It has been proposed that the autocleavage of the switch protein is the trigger for substrate switching. We show here that autocleavage of theSalmonella entericaserovar Typhimurium switch protein SpaS is an unregulated process that occurs after its folding and before its incorporation into the needle complex. Needle complexes assembled with a precleaved form of SpaS function in a manner indistinguishable from that of the wild-type form. Furthermore, an engineered mutant of SpaS that is processed by an external protease also displays wild-type function. These results demonstrate that the cleavage eventper sedoes not provide a signal for substrate switching but support the hypothesis that cleavage allows the proper conformation of SpaS to render it competent for its switching function.IMPORTANCEBacterial interaction with eukaryotic hosts often involves complex molecular machines for targeted delivery of bacterial effector proteins. One such machine, the type III secretion system of some Gram-negative bacteria, serves to inject a multitude of structurally diverse bacterial proteins into the host cell. Critical to the function of these systems is their ability to secrete proteins in a strict hierarchical order, but it is unclear how the mechanism of switching works. Central to the switching mechanism is a highly conserved inner membrane protease that undergoes autocatalytic cleavage. Although it has been suggested previously that the autocleavage event is the trigger for substrate switching, we show here that this is not the case. Rather, our results show that cleavage allows the proper conformation of the protein to render it competent for its switching function. These findings may help develop inhibitors of type III secretion machines that offer novel therapeutic avenues to treat various infectious diseases.

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