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Tension impact during dynamical process would have a disadvantageous effect on tension control system based on permanent magnet synchronous motor(PMSM) for flexible rope applications, and a novel anti-impact tension control strategy is proposed in this paper. The model of tension control system containing flexible rope and the reason for difficulty in solving tension impact by using traditional proportional integral(PI) control is analyzed. The proposed control strategy realizes the establishment of tension and the suppression of tension impact through the optimization of integration regulator in a PMSM-based rope tension control system. The simulation and experiment results from a tension control platform prove the dynamic performance and steady state precision of the proposed control strategy and show the advantages on the tension control for flexible rope applications.

The dual winding induction generator system uses flux-oriented control strategy to adjust the active current and reactive current separately, thereby to obtain stable control of the system. Among them, the control performance of active current and reactive current affects the entire system. This article introduces two current control strategies for dual winding induction generator systems, as well as their comparison and performance. These two control strategies include Proportional Integral Current Control (PI-CC) and Deadbeat Predictive Current Control (DP-CC). The control strategy is compared from two aspects of implementation and performance. From the comparison results, DP-CC has better performance and is simpler to implement.

In this paper, a flux linkage adaptive direct torque control (DTC) method for permanent magnet synchronous motor (PMSM) drive is investigated to increase power factor without stabilizing stator flux at a constant value. Using this method, the stator flux linkage amplitude will be changed adaptively according to load variation. The control system scheme and analysis model for this method are presented and studied. A prototype PMSM is employed for the experiments under different load. The experimental comparison between the traditional and presented methods shows that the flux linkage adaptive DTC can improve the dynamic performance of the system and effectively increase power factor.

The operating principle and electromagnetic characteristics under no-load condition of 12/10 pole flux-switching permanent magnet motor(FSPM) are studied using the finite element analysis software in this paper. By changing the stator permanent magnet width, the rotor tooth width and the rotor tooth height, the influence of structure parameters on the no-load electromagnetic characteristics of FSPM is explored, which is helpful to its optimal design.

Induction motors are widely applied in the fields of industry with the merits of simple structure, stable performance and convenient manufacturing. However, in some servos with high reliability requirements, the installation of the speed sensor not only increases the volume and the weight, but also reduces the reliability of the driving system. To solve this problem, speed-sensorless technique has gained an increasing number of attention and research. This paper proposes the adaptive full-order (AFO) observer based on bilinear transformation, simulation has been done to prove the effectiveness.

In this paper, an improved speed synchronization control algorithm based on cross coupling is proposed for dual servo motors control. This method controls two motors synchronously from the angle of bandwidth and solves the problem of controlling the coupling of the target in the traditional speed cross coupling control algorithm. It has a clear control target and can realize the speed synchronization of the two motors more effectively. In this paper, a series of simulation results are given to verify the effectiveness of the improved speed control algorithm based on cross coupling.

This paper proposes a novel self-bearing dual stator solid rotor axial flux induction motor (BDSSRAFIM) which combines axial thrust magnetic bearing and rotating electric motor for flywheel energy storage system (FESS). First of all, development of FESS is briefly introduced. Secondly, in order to control BDSSRAFIM accurately, this paper analyzes its construction and characteristics, derives a valid equivalent mathematic model and proposes a differential excitation vector control method which is based on air gap magnetic field orientation. Finally, a 5kW BDSSRAFIM prototype is designed and set up for experiments. The effectiveness of method is verified by simulation and experimental results.

The structural parameter optimization to reduce cogging torque of the consequent pole in-wheel motor (CPM) is studied in this paper. The analysis model of calculating the cogging torque is derived by the energy equations and finite-element analysis (FEA) is carried out for accurate numerical simulation of the cogging torque. The difference between the consequent pole structure and the conventional structure is investigated firstly. Then the influences of structural parameters on the cogging torque, such as pole arc coefficient and widths of slot opening are calculated and analyzed. Beyond that, the slot-pole match and curved iron core to reduce cogging torque are studied. Through the analysis of calculation results, the optimized structural parameters are obtained, and experiment results from two prototypes demonstrate the correctness and feasibility of the proposed methods.

This paper presents a random space vector pulse width modulation (SVPWM) strategy for a three-phase voltage source inverter based on Field Programmable Gate Array (FPGA). It is more flexible and faster to realize randomization algorithm in FPGA than digital signal processor (DSP). What's more, it is easily extensible for multiphase driving systems with FPGA. Models in Simulink and an experiment platform with FPGA have been built up. Results of experiments have proved the correctness of the proposed strategy and the effectiveness and feasibility of implementation using FPGA.

A novel tubular transverse-flux flux-reversal permanent magnet linear motor (TTFFRPMLM) for long stroke applications is designed and analyzed in this paper, which not only has the low cost advantage of the existing flux-reversal motor (FRM) by combining both PMs and armature coils in short primary, but also can address the problem of complicated structure of the existing transverse-flux motor (TFM) by using rotating motor technology. The structure of the motor are introduced. The topology and operating principle of the motor are presented and analyzed. The performance of the motor is optimized by equivalent 2D finite element method (FEM). The simulation results of the 3D FEM prove the correctness and effectiveness of the motor topology and equivalent 2D FEM. The research work of this paper provides the theory basis for the engineering application of this novel motor.

This paper investigates the harmonic voltage control strategy of direct torque control for five-phase induction generator (IG) system. In high/medium power applications, the generating function requires the performance of fast dynamic response, good static performance and high utilization of the dc bus voltage. For IG generating system, the direct torque control strategy has the advantages of easy implementation and great performances with load. Harmonic current injection is studied to improve the torque density of multi-phase machine. However, the direct torque control is not fit for that current control loop is not existed. To solve this problem, harmonic voltage control is proposed to study the performance of five-phase IG system. The simulation results and experimental results are given to verify the control strategy.

This paper, based on the three dimension (3D) coordinates, presents the cause of the zero-sequence voltage in the open winding asynchronous motor system which is driven by double inverters with single power supply. The large vectors which have zero-sequence voltage are selected to realize PWM. For eliminating the zero-sequence voltage, the space zero vectors are inserted in every control period. This modulation algorithm is easy to be realized by digital controller. The validity of the proposed method has been verified by MATLAB simulation.

In this paper, two dual random space vector pulse-width modulation (RSVPWM) methods, Random Switching Period-Random Zero Vector Timing SVPWM (RSP-RZVT-SVPWM) and Variable Daley-Random Zero Vector Timing SVPWM (VD-RZVT-SVPWM), are proposed to apply in five-phase inverters. The proposed RSVPWM methods can decrease the amplitudes of high harmonics and spread harmonics concentrated around switching frequency and its integer times to a wider frequency band. The dual RSVPWM has a more continuous and uniform power spectrum which will alleviate acoustic noise and restrain electromagnetic interference (EMI) of the system effectively. In this paper, a series of simulation results are provided to verify the effectiveness of the two dual RSVPWM methods for five-phase inverter.

For hybrid AC& DC micro-grid, this paper proposes a new generating system based on dual stator-winding induction generator (DWIG). This generating system can realize bidirectional energy flow, reduce the number of converters and simplify the structure of micro-grid. To meet the requirement of supplying AC and DC power simultaneously, this paper proposes the control winding voltage oriented (CWVO) control strategy on the basis of instantaneous reactive power theory. Through the analysis of simulation results, the feasibility and accuracy of this generating system and its control strategy is validated. This paper lays the foundation for future research for hybrid AC& DC micro-grid.

For the detection of rotor position in Permanent Magnet Synchronous Motor (PMSM), this paper presents an improved estimation method with switch-Hall-effect sensors. This algorithm can reduce the position error effectively originating from the process of estimation. In the course of estimation, coordinate transformation and an improved orthogonal PLL (Phase locked loop) which can decrease the oscillation availably of velocity are adopted successively. In order to validate the superiority of the method, simulations based on MATLAB/Simulink with high-precision sensor, typical PLL and improved PLL are built here. Analysis of the results and comparisons between waveforms of above models indicate the feasibility of the proposed strategy.

This paper proposes a novel dual-frequency space vector pulse width modulation strategy for the five-phase voltage source inverter, which contains fundamental frequency and third harmonic frequency. The proposed strategy has the advantages of half-wave symmetry, outputting dual frequency voltages and currents, reducing the switching times, and balancing the switching times of top device and bottom device. Based on the fast fours transformer (FFT) analysis, the third harmonic components are trade with the command value. It indicates that the two components (fundamental and third) are regulated greatly by this proposed strategy. The principle and performance of this strategy are verified by the MATLAB simulation finally.

This paper presents the mathematical model of dual-stator-winding induction generator (DWIG) for aircraft variable frequency ac generating system under asymmetric operation. Firstly, the asymmetric mathematical model of DWIG under the A-B-C three-phase static coordinate system is built. Then, for the asymmetric operation, the zero-axis component is considered, and the asymmetric mathematical model of the DWIG in the d-q-0 three-phase orthogonal rotating coordinate system is obtained. Based on this, the simulation of the DWIG and whole system is built in the MATLAB/ SIMULINK Simulation and experiments are carried out under single-phase full load, two-phase full load and three-phase asymmetric load. The results of simulation and experiment prove the correctness of the mathematical model.

An improved quasi-z-source dual-inverter for open-end winding induction motor drives is presented in the paper. The improved quasi-z-source dual-inverter can not only realize boost/buck function, but also suppress DC-link bus overshoot voltage, which is suitable for medium/high-power level. The topology allows shoot-through state, so that the dead-time effect cannot be existed. The dual-inverter belongs to the three-level drive system. The utilization rate of DC-link bus voltage is accordingly improved. The proposed topology has high reliability, strong fault tolerance and single-stage boost/buck voltage function, bidirectional energy flow, except simple structure and low cost of open-end winding induction motor. Due to strong fault tolerance and boost function in the proposed topology, the dynamic performance of the drive system can be significantly improved. The operating mode and the modulation method are analyzed in this paper. The simulation and experimental results can verify the feasibility of the improved topology for the motor drives.

In this paper, the model of the third-harmonic-injected five-phase dual stator-winding induction generator (FPDWIG) is presented. There are two sets of five-phase concentrated stator windings in this generator. One is called as the control winding, the other is termed as the power winding. For improving the power density, the third harmonics are injected in this generator. With the consideration of the differences of the fundamental and third harmonic spaces, the model of the third-harmonic-injected FPDWIG is built in the rotating d 1 -q 1 -d 3 -q 3 arbitrary reference frame. The dynamic equivalent circuits of FPDWIG in the rotating d 1 -q 1 -d 3 -q 3 arbitrary reference frame are given. Based on this method, FPDWIG simulating model is built in the MATLAB/SIMULINK and the simulation results is given for verification.

This paper presents a dc generating system based on the five-phase dual stator-winding induction generator (DWIG) with the static excitation controller (SEC), and also investigates its control strategy. In this five-phase DWIG, the cage-type rotor is employed and it has two sets of five-phase stator windings (power winding and control winding). Based on the instantaneous power theory, a control winding field oriented control (CWFOC) strategy considering third-harmonic injection is proposed. The simulation results support the proposed control strategy, the five-phase DWIG dc generating system can have a good performance.

The coupled-inductor single-stage boost inverter (CI-SSBI) has been proposed and applied to photovoltaic (PV) power system. The CI-SSBI based grid-connected PV system integrates some characteristics together in one stage, including boost inversion, feeding current to the grid with high power factor, and maximum power point tracking (MPPT). Moreover, system reliability can be improved by using the shoot-through zero states as a normal operation mode. This paper focuses on the control analysis of both bus voltage loop and inner current loop of the proposed PV system. Experimental results are presented to verify the analysis and show the real system performance.

The performance of direct torque control (DTC) is closely related to the precision of flux linkage which calculated by electromotive force (EMF), especially at low speed. To improve the torque performance of DTC, this paper analyzes the influence of dead-time and presents the corresponding compensation method. The influence of parasitic capacitances is taken into account for accurate compensation, and the indirect nonlinear compensation is proposed. The validity of the proposed method is verified by experimental tests.

This paper presents an improved direct torque control (DTC) method for permanent magnet synchronous motors. The proposed DTC method generates the diver signal with SVPWM for the fixed switching frequency and low torque ripple relative to conventional hysteresis controllers. Different with the popular SVM-DTC, the proposed method obtains amplitude and angle of reference voltage vector directly by the torque and flux linkage loop respectively without complicated calculations that reproduces the simplicity and robustness of conventional DTC. Furthermore, the observation and control of torque angle in the proposed method ensures the PMSM operating stably. The validity of the control method is verified by experimental tests.

This paper presents an instantaneous slip frequency control (ISFC) strategy for the dual stator-winding induction generator (DWIG) variable frequency AC (VFAC) power system. In this ISFC scheme, the information of both the output voltage and the output power is employed to guarantee the system has a desirable static and dynamic performance. The experimental results on a 15 kW prototype verify the principle and performance of the proposed control method.

In this paper, an optimal scheme of excitation capacitor for 6/3-phase dual stator-winding induction generator (DWIG) system applied in wind power is presented. Through the analysis of the excitation reactive power released by the excitation capacitor and the static excitation controller (SEC), the optimal selection of excitation capacitor not only is related to generator parameters, speed range, and load, but also affected by wind turbine power curve. In order to minimize the capacity of SEC, an appropriate excitation capacitor is determined by calculation and simulation. On the basis of this, the experimental works from the prototype of 18 kW 6/3-phase DWIG wind power system are carried out to verify the optimal scheme, and the results prove the correctness and effectiveness of this optimization scheme.

The magneto motive force (MMF) of a novel dual stator-winding induction generator (DWIG) for wind power application is analyzed in this paper. There are two sets of windings embedded in the stator slots. One is 3-phase control winding, and the other is 6-phase power winding. A static excitation converter (SEC) is connected to the control winding to provide the variable excitation power to the generator. The 6-phase power winding, feeding a 6-phase rectifier, is designed as two 3-phase star windings spatially shifted by 30° electrical to decrease the harmonic MMF. Based on the analysis on the harmonic current components of the two sets of stator windings, the harmonic MMF in this generator is investigated, and the relationship between the harmonic current and harmonic MMF is consequently disclosed. The harmonic MMF in a 18 kW DWIG prototype is calculated, and the correctness of harmonic MMF analysis is verified.

To apply the dual stator-winding induction generator (DWIG) system in wind power, the optimal scheme of excitation capacitor to decrease the capacity of static excitation controller (SEC) is proposed in this paper. The optimization of excitation capacitor not only have much to do with the generator parameters and speed range, to some extent, but also are affected by wind turbine power curve and the types of loads. Based on the objective of minimizing capacity of SEC, the graphic and iterative methods are employed to achieve the optimal capacitor with the resistance load. However, for the rectifier load, this optimal capacitor should be modified properly by the way of simulation. The simulation and experimental results from the prototype of 18 kW 3/3-phase DWIG wind power system are shown to demonstrate the validity of the optimal scheme.

In order to capture the maximum wind energy and improve the efficiency of wind generation system, the yaw control system is researched. This system takes the initiative to windward. According to the control algorithm proposed in this paper, yaw angle is calculated by the DSP, and the drive signals of stepping motor are generated. The stepping motor is controlled by the micro-stepping control to drive the yaw mechanical device to make the wind turbine windward. Through this way, the yaw control system can track the wind direction automatically. Experimental results show that based on the proposed control algorithm and DSP control, the performance of yaw system is great and the operation precision of stepping motor is high. Therefore, the yaw system has the ability to track the wind direction quickly and exactly.

This paper presents a novel dual stator-winding induction generator (DWIG) system used in wind power generation. Based on the control winding field orientation, an indirect field-oriented control strategy is proposed for a simple realization to control the DWIG system. The voltage control mechanism of the DWIG system over variable-speed operation of the power system is analyzed in detail. The component of the control winding current which are produced on the control winding terminal voltage vector and its normal component determine the instantaneous reactive power and active power, and further influence the DC voltage of the load connecting across the power windings and that of the static excitation controller (SEC) on the control windings. Simulation and experimental results on a 20kW/750rpm DWIG are provided to demonstrate the effectiveness and accuracy of the proposed control strategy.

The usual dual-stator winding induction generator (DWIG) is composed of 3-phase power winding and 3-phase control winding, defined as 3/3-phase DWIG. The power winding has only three phases, and connects to a rectifier load, which results in larger harmonic magnetomotive force (MMF) in the generator. In order to overcome this problem and improve the performance of the DWIG system, the power winding of 3/3-phase DWIG is converted from three phases to six phases. A novel 6/3-phase DWIG with six phase power windings and three phase control windings is proposed. The six power windings of it are divided to two Y windings shifted by 30° electrical angle. In this paper, in order to further study the static and dynamic characteristics of 6/3-phase DWIG system with a rectifier load, harmonic MMF in generator are analyzed in detail. The corresponding relationship between the harmonic current and harmonic MMF is achieved. Based on these, the model of a 600 V/18 kW 6/3-phase DWIG system is built-up. The simulation and experiment results indicate that the 6/3-phase DWIG system has excellent performance over the wide speed rang and is suitable for the application of wind generation.