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The purpose of this paper is to present a complete solution for speed sensorless AC drive with voltage source inverter, induction machine, and motor choke. Major problems with adjustable speed drives are underlined and the use of motor choke is justified. An AC drive with motor choke can work only if specific modifications in the control algorithms are done.

The goal of the paper is to present new nonlinear vector control method for induction motor drive. In the control system, the presence of motor choke is taken into account. The choke changes the structure of the predictive controller and state observer. The new concept of integrating the predictive controller with electromagnetic forces observer is presented. The paper presents theoretical description of the system as well the simulation and experimental verification.

The paper shows that the suggested decoupled AC drive control system is operating better than a system without decoupling. The system with motor choke requires modifications in the current controller and observer system. With omitting the motor choke a speed sensorless drive cannot work properly.

The solution is oriented for industrial applications because in numerous industrial dives the motor choke is utilized. However, with motor choke many sophisticated control algorithms cannot work properly. The concept presented in the paper solves such practical problems.

The paper presents a completely new decoupled field‐oriented control system with load angle controller, predictive current controller and state observer for AC drive with motor choke.

Purpose – This paper presents the performance of medium voltage induction motor drive fed through a bidirectional quasi z-source inverter (BQ-ZSI). By controlling the shoot-through duty ratio, BQ-ZSI is able to produce desired stable ac output voltage even during the situation of critical power supply variation. BQ-ZSI based drive has unique properties like boosting the output voltage during voltage sag, reducing harmonic distortion and improving the input power factor. Generally, adjustable speed drives (ASD) are interrupted due to voltage sag in input supply that causes manufacturing and commercial losses. Replacing the conventional converter with BQ-ZSI, it can eliminate those common operational constraints.

This purpose is validated through simulations using real-time digital simulator (RTDS). RTDS is based on FPGA that interfaces the digital and analog I/O ports of the external hardware device. The IGBT based BQ-ZSI closed loop induction motor drive is modelled in SIMULINK and analysed through state space averaging technique. The suitable controllers are assigned and implemented on FPGA. The performance of the whole system is executed by offline simulation and analysed in hardware-in-loop (HIL) real time simulator with fixed-time step. HIL simulation plays important role in design and development stage for BQ-ZSI based medium voltage drives where virtual plant is executed instead of physical plant.

Real-time simulation results show the performance of 225KW, 3.3KV induction motor for BQ-ZSI based motor drive under both steady state and dynamic conditions. The applied closed loop control method provides nearly zero steady state speed error at any operating frequency.

The application of BQ-ZSI is explored for medium voltage drive to solve the issues of power supply quality through the design of suitable control solution. Performance results presented in this paper can help in development of simple and low cost prototype controller for the drive.

Induction motors (IMs) are considered one of the most important elements of the industrial process. However, in this environment, these machines are subject to electrical and mechanical faults, which may cause significant financial losses. Thus, the purpose of this paper is to propose an optimal identification of inter-turn insulation faults present in the random wound IM.

The design approach deals with a simple technique, using the effect of the inter-turn fault in modifying the high-frequency components of the applied pulse-width-modulated voltage.

The change in insulation strength between the turns affects the capacitive component of the stator line current. Resulting changes in wave shapes of the applied voltage have been studied with respect to both the distance of inter-turn faults from line end and reduction in the insulation strength, and hence in the insulation resistance value.

Studies have been conducted by using computer simulation and validated by experiments. There is ample evidence that an impending and progressing inter-turn fault can be identified in adjustable speed drives driven by frequency converters by studying line-end coil-voltage waveforms.

This paper aims to present the impact of Pulse Width Modulation (PWM) control frequency for specific Permanent Magnet Synchronous Motors (PMSMs) on the efficiency of the entire driving unit. Examinations were carried out for a PMSM unit with a power of 1 kW, rated speed of 1,000 rpm, and rated torque of 6 Nm.

The PWM frequency ranged from 4 to 20 kHz with increments of 1 kHz. Measurements were taken for each of the foregoing frequencies, for the different load torques, and for the different rotation speeds including overspeed. The results achieved allow the PWM control frequency to be properly adjusted for each PMSM to operate the entire driving unit in the most efficient way and, in consequence, save energy consumed by the drive.

Obtained results may be used as a kind of background for the design of drive system.

For a specific PMSM-based drive system, one can find the optimal PWM control frequency. This frequency depends on the rotation speed and torque of the motor. However, the validity of the results presented in the paper is limited. They are valid for the specific motor drive under test and cannot be generalized easily.

This work shows that there is some maximal efficiency of the entire system depending on the rotation speed, load torque and switching frequency of the power transistors. For a specific motor working in a certain condition, we can find the minimum power loss.

The purpose of this paper aims to design a robust wind turbine emulator (WTE) based on a three-phase induction motor (3PIM).

The 3PIM is driven by a soft voltage source inverter (VSI) controlled by a specific space vector modulation. By adjusting the appropriate vector sequence selection, the desired VSI output voltage allows a real wind turbine speed emulation in the laboratory, taking into account the wind profile, static and dynamic behaviors and parametric variations for theoretical and then experimental analysis. A Mexican hat profile and a sinusoidal profile are therefore used as the wind speed system input to highlight the electrical, mechanical and electromagnetic system response.

The simulation results, based on relative error data, show that the proposed reactive power control method effectively estimates the flux and the rotor time constant, thus ensuring an accurate trajectory tracking of the wind speed for the wind emulation application.

The proposed architecture achieves its results through the use of mathematical theory and WTE topology combine with an online adaptive estimator and Lyapunov stability adaptation control methods. These approaches are particularly relevant for low-cost or low-power alternative current (AC) motor drives in the field of renewable energy emulation. It has the advantage of eliminating the need for expensive and unreliable position transducers, thereby increasing the emulator drive life. A comparative analysis was also carried out to highlight the online adaptive estimator fast response time and accuracy.

The purpose of this paper is to implement the macro-modeling and passivity enforcement for the equivalent high frequency circuit model of a single-phase winding for an alternating current (AC) three-phase motor. It provides a stable and strictly passive Foster-type circuit macro-model for the winding. Consequently, a stable circuit network is guaranteed when it is connected with an external passive circuit. The equivalent circuit is validated on a three-phase permanent magnet synchronous motor. Furthermore, the corresponding three-phase windings macro-model could be obtained accordingly.

The following techniques are used: the least square method, vector fitting method, the fast residue perturbation method, circuit synthesis, sequence quadratic programming method and simulated annealing method.

This work presents an effective approach to model an equivalent high frequency circuit macro-model for a single-phase winding. Simultaneously, both the characteristics of port passivity and component passivity are guaranteed.

This paper carries out both the port passivity and the component passivity enforcement for a single-phase winding of a motor during the macro-modeling procedure. This equivalent motor winding model can be applied to obtain the conducted electromagnetic interference and the overvoltage performance analysis for an adjustable speed motor drive system.

Recently there has been considerable technological change in the way in which safety‐related control may be engineered. A series of standards based upon IEC 61508 are under development. This paper discusses these changes and highlights their relevancy to machine safety.

An overview of technological change is given; from safety relays, to programmable safety controllers, safety‐related networks and the trend to combine safety and control functions in controllers and networks. Topics to consider when choosing between technologies are put forward, followed by a review of standards that incorporate functional safety.

The development of safety‐related standards, such as IEC 61508 provides general guidance on the design of safety‐related systems across a wide range of industries, with specific machinery implementation of the same principles in IEC 62061. There is overlap between IEC 62061 and ISO 13849‐1. The same functional safety principles are also implemented in IEC 61800‐5‐2 for adjustable power drive systems. IEC 61784‐3 embodies the functional safety concept in specific network technologies. Significant opportunities arise from the combination of technology and standards development to facilitate design, engineering and cost improvements.

Confusion is apparent in the application of emerging safety standards, coupled with dramatic changes in the approach to safety engineering. Areas of overlap between developing standards are highlighted, along with draft amendments intended to reduce potential conflict and perplexity. Incorporating functional safety into automation and industrial networking technologies enables engineers to produce innovative solutions that can lead to further improvements in machine safety, functionality, productivity and afford design, commissioning and maintenance benefits. Similar benefits are unlikely to be achievable with traditional safety technologies.

Areas of overlap between developing standards are highlighted, with amendments intended to reduce confusion in the intended audience. This paper seeks to raise awareness in the methods and benefits of incorporating functional safety into automation and industrial networking technologies.

The purpose of this paper is to investigate the impact of different distribution of shoot through mode on Z‐source inverter efficiency and particularly on complexity of switching pattern generation. Switching pattern generation has been optimized for field‐oriented control (FOC) of induction motor operating beyond its nominal speed which can be easily accomplished due to the input voltage boosting implemented inherently by Z‐source inverter. The proposed drive is unaffected to supply voltage sags, too.

The space vector modulation switching pattern of the traditional FOC drive was modified in order to insert shoot through mode necessary for input voltage boosting. Since this can be accomplished only on account of zero mode of the inverter, the active modes have to be reduced. Consequently, the output voltage space vector has to be reduced, as well.

In order to maximize profit of the input DC voltage and to omit the output voltage distortion, mathematical limitations have been derived giving the optimal boost ratio for required output voltage and ride‐through capability during voltage sags.

The experimental tests of upgraded FOC of induction motor with the proposed distribution of shoot through mode in the switching pattern of Z‐source inverter and optimized control of inverter voltage are demonstrated. It is also shown that such a drive can withstand a long period of input voltage sags and operate in a broader field weakening regime.

The paper's value lies in the overall, DSP‐based control of the induction motor supplied with Z‐source inverter gaining the maximum utilization of the input DC supply source and optimum trade‐off between inverter efficiency and inverter components voltage stress.

This paper aims to study modeling of the nonlinear behavior of the Torus machine back EMF using an adaptive networks fuzzy inference system (ANFIS). The model can be used to study the steady‐state as well as the dynamic performances of the machine operating as a motor or as a generator.

Using the universal approximation capability of fuzzy systems the authors designed an ANFIS network to model the nonlinear behavior of the back EMF of the Torus motor. The ANFIS is trained using an actual set machine measurements data to generate the motor back EMF for different operating conditions.

Simulation results of the ANFIS model of the Torus motor at different loads proved the ability of the algorithm to effectively model the complex electromagnetic behavior of the machine. Such efficient modeling can directly help in improving and optimizing the Torus motor drive system design.

It demonstrates that ANFIS can model the nonlinear behavior of the back EMF of the Torus motor with excellent accuracy.