Modelling and indirect field‐oriented control for pole phase modulation induction motor drives

This paper proposes a propulsion control algorithm considering End-effect of a linear induction motor (LIM) used in a magnetic levitation train. Indirect field oriented control (IFOC) technique is one of the popular control techniques widely applied to LIM drive control. The main idea of IFOC in a LIM is the decoupling of the flux and torque. Therefore, IFOC has a higher dynamic characteristic than the scalar control [1]. The LIM applied to the magnetic levitation trains should control the thrust force and also take into account the normal force for levitation stabilization. When the LIM is driven, normal force is inevitable. The normal force is a function of the speed, the slip frequency and the current of the train. In the rotary type induction motor, the normal force is canceled due to its symmetrical structure. Therefore, IM could operate in a low slip and high efficiency range. However, in the case of LIM, a high attraction force is generated in a low slip region, which cause the instability of the levitation system. Therefore, the propulsion control for magnetic levitation trains must operate in a higher slip region than the slip used in conventional IFOC. In this paper, the slip characteristics of the LIM are analyzed to improve the efficiency and safety of the magnetic levitation train by FEM analysis. A constant slip frequency propulsion control algorithm is proposed for operation in the analyzed slip region. The proposed algorithm can be controlled by separating magnetic flux and thrust from IFOC. The proposed algorithm is verified in 250 kW test bench. The results of FEM analysis according to speed and slip at constant voltage condition are shown on Fig. 1. The dotted lines of Indirect Field Oriented Control(IFOC) and Constant Slip Indirect Field Oriented Control(CSIFOC) are shown on the figure. The slip of the IFOC is low and that leads to operate near the maximum thrust and efficiency. However, the normal force of LIM is also increase, which could not be allowed in maglev application. On the other hand, when CSIFOC is performed considering normal force, the slip is higher than the conventional algorithm. Although the CSIFOC is not operated in maximum thrust slip, the normal force could be greatly reduced. Fig.2 (a) shows the CSIFOC algorithm considering the end-effect of the linear induction motor. In general IFOC, the d-axis current reference is calculated through the magnetic flux reference value, and the q-axis is calculated based on thrust. However, the CSIFOC for the LIM generates the d-axis and q-axis current references along with the slip frequency and thrust. Fig. 2 (b) shows the waveform of the experimental results based on the general IFOC and the proposed algorithm. Both IFOC and CSIFOC were tested with the same rate pattern of the same load. It is confirmed that CSIVC has larger slip than conventional IFOC and low normal force in all regions. In this paper, a constant slip frequency IFOC algorithm is proposed considering the end effect of LIM used for magnetic levitation trains. The efficiency, thrust and normal force according to the speed and slip through the FEM analysis of the LIM were analyzed and the slip condition suitable for the magnetic levitation train is proposed. In addition, a current reference generation algorithm based on the thrust and slip is proposed in the IFOC considering the end effect to operate under the proposed slip condition. In the full paper, the detailed formulas of the proposed algorithm are developed and will be verified through simulation and experimental results.

In this paper, indirect field oriented control (IFOC) of induction motor at very low speed range (1-5 rpm) using a low-count encoder is presented. To test the lowest possible pulse encoder that gives both satisfactory performance for IFOC algorithm and precise enough speed information, a low-count encoder implementation algorithm is developed. This algorithm converts high-resolution encoder data to various number of pulse low-count encoders. Using this algorithm, different pulse encoders are tested and the lowest possible pulse encoder is selected for IFOC implementation due to the cost limitation. Furthermore, solutions to computational problems of microprocessing unit associated with low speed measurement techniques are given. These contributions are experimentally tested and successfully applied to digital signal processor (DSP)- based (TMS320F28xx) ac drives used in traction applications.

Indirect vector control or Indirect Field Oriented Control (IFOC) is known to produce high performance in induction Motor (IM) drives by decoupling rotor flux and torque producing current components of stator current. The most commonly used controller for the vector control of ac motor is Proportional- Integral (P-I) controller. However, the P-I controller has some disadvantages such as high starting overshoot, sensitivity to controller gains and sluggish response to sudden disturbances. So, the Integral-Proportional (I-P) controller is proposed as speed controller for induction motor drives to overcome the disadvantages of the P-I controller. Simulation results are presented and analyzed for both the controllers and it is observed that Integral-Proportional (I-P) controllers give better responses than the traditional P-I controllers for the Indirect Field Oriented Control (IFOC) of ac motor drives.

Induction Motor in Electrical drive system at a accelleration speed for example in electric cars have a hard speed setting is set on a wide range, causing an inconvenience for motorists and a fast response is required any change of speed. It is necessary for good system performance in control motor speed and torque at low speed or fast speed response, which is operated by Indirect Field Oriented Control (IFOC). Speed control on IFOC methods should be better to improving the performance of rapid response in the induction motor. In this paper presented a method of incorporation of Fuzzy Logic Controller and Backstepping (Fuzzy-Backstepping) to improve the dynamically response speed and torque in Induction Motor on electric car, so we get smoothness at any speed change and braking as well as maximum torque of induction motor. Test results showed that Fuzzy-Backstepping can increase the response to changes speed in electric car. System testing is done with variations of the reference point setting speed control system, the simulation results of the research showed that the IFOC method is not perfect in terms of induction motor speed regulation if it’s not use speed control. Fuzzy-Backstepping control is needed which can improve the response of output, so that the induction motor has a good performance, small oscillations when start working up to speed reference.Keywords: Fuzzy-Backstepping, IFOC, induction motor

The pole phase modulation (PPM) technique is an effective method to extend speed range and torque capabilities for an integrated starter and hybrid electric vehicles applications. In this paper, the five pole-phase combination types of a multiphase induction motor (IM) with 36 stator slots and 36 stator conductors are presented and compared quantitatively by using the time-stepping finite element method (TS-FEM). The 36 stator conductors of the proposed multiphase IM are fed by a 36 leg inverter and the current phase angle and amplitude of each stator conductor can be controlled independently. This paper focuses on the winding connection, the PPM technique and the performance comparative analysis of each pole-phase combination types of the proposed multiphase IM. The flux distribution, air-gap flux density, output torque, core losses and efficiency of five pole-phase combination types have been investigated.

Indirect field oriented control (IFOC) and direct torque control (DTC) have been widely commercialized in induction motor drives, with each being favored by its supporters. In this paper, the dynamic performance of these drives for an electric vehicle application is examined, and sensitivities to parameter variations affecting this dynamic performance are explored. Key performance measures include torque and speed transients. To achieve decoupling between the drive and the switching scheme, both drives are simulated in MATLAB/Simulink for different switching schemes. These schemes include space-vector pulse-width modulation (SVPWM), and hysteretic control for IFOC and DTC. DTC is also simulated with a switching table. Experimental results for some of these schemes are also presented. Results show that control performance is influenced by the switching scheme. It is shown that when IFOC and DTC are used with SVPWM, the torque response of IFOC is superior. These characteristics are verified by simulations. The work opens further discussion for the feasibility of applying IFOC in electric and hybrid-electric vehicles.

The purpose of this paper is to address improvement of the dynamic and load torque rejection of the indirect field oriented control (IFOC), of an induction motor (IM), by replacing all proportional-integral (PI) controllers with intelligent components: fuzzy logic controllers (FLCs). The controllers substituted, are those of the speed and the stator currents of the IFOC. The performance of the proposed fuzzy control structure, of the IM, was studied in different operating conditions, and was compared with the PI control performance in the same conditions. Simulation tests prove the robustness and relevance of the unique structure of fuzzy logic control based IFOC, in different speed ranges with the application of a load.

The pole phase modulation (PPM) principle is gaining attention in the squirrel induction machine design to be used for high speed applications in industries and for electric vehicle drives requiring increasing operating speed range. This principle signifies one of the advantages of using multiphase machines in variable speed-torque requirements. In this paper a design and an analysis of a multiphase induction machine for a variable speed drive (PPM) principle is presented. The results obtained from a 3 phase, 12 pole and 9 phase, 4 pole machines are analyzed to demonstrate the performance possible using (PPM) principle for speed control. The 3 phase, 12 pole configuration can be used for low speed and high torque applications. Similarly, the 9 phase, 4 pole configuration is used for high speed and low torque applications. The design of the machine for this operation relies on the concepts of turn and winding functions, and winding layouts. Finite element analysis for both winding configurations validates the winding design. Simulation results show that multiphase squirrel cage induction machines can be operated in both the configurations according to the speed and torque requirements simply by reconfiguring the stator windings.

Use of induction motor (IM) at it's highest efficiency is a big demanding task because of their complex mathematical model and non linear features during saturation. These elements make the control of IM strenuous and call for the use of high performance control algorithm such as field orientation control. This paper introduces a speed controller, particularly at minimum speeds by utilizing Fuzzy logic controller (FLC) for indirect field-oriented control (IFOC) of induction motor (IM) drives fed by a four-switch three-phase (FSTP) inverter. From suggested viewpoint, the IM drive is used with a FSTP inverter as an alternative for the conventional six-switch three-phase (SSTP) inverter. Utter IFOC programme includes the FLC of IM drives with the suggested FSTP inverter is raised in MATLAB/Simulink. By considering the good dynamic performance, cost minimization and low total harmonic distortion (THD), FSTP inverters are comparable with SSTP inverters. The dynamic performance and robustness of proposed FLC with the FSTP inverter fed IM drive is verified with PI controller. It is established that the suggested FLC is further powerful than the PI controller under speed tracking and load disturbances

Indirect Field Oriented Control (IFOC) is very popular technique in industries due to its simple designing and structure, in comparison to the direct method since it requires flux and torque estimators. This paper presents detail calculation of all values needed for the development of an indirect rotor flux oriented induction motor model fed by a current-controlled voltage source inverter. With the calculated values for 1 hp 50 Hz 3 phase induction motor; an indirect rotor flux oriented model is developed using MATLAB/Simulink. The simulation results are outlined and discussed.

The multiphase motors due to their reliability find new areas of application in the industry and transportation. Developing of any system with multiphase motors at first requires elaborate model of the system, define control mode and controllers. The model of control system for the sixphase drive is based on its conventional d-q mathematical model and indirect field-oriented control. Simulink model of six-phase drive with indirect field-oriented control and simulated with two types PID and PID fuzzy controllers. The simulation results, reflecting step response and provided speed reference law as well as load application at constant speed, are presented and analyzed. Fuzzy controller with 49 rules is considered and applied. Six-phase electric drive with field-oriented control at well-tuned PID controller has good step response specifications: settling time 0.13 s at starting without load, step response has no overshoot, small about 1% short time decrease of speed at load of 5 Nm application. The system employing PID fuzzy controller shows slightly better results in response to torque application: the decrease in speed 1% is eliminated in shorter time. Simulation results indicate the robustness of both systems with six-phase drive to disturbance and provide high quality transient specifications at provided reference speed.

This paper proposes a novel optimized control strategy of quasi-Z source indirect matrix converter (QZS-IMC) for induction motor drives. The QZS-IMC provides boost function to overcome the output voltage limit of the traditional matrix converter, and achieves a voltage gain over 0.866. This paper proposes an indirect field oriented control (IFOC) technique based closed loop speed control of an induction motor fed by a QZS-IMC. By selecting the best optimized shoot-through duty ratio (D), modulation index (m <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">i</sub> ;) of the rectification stage and modulation index (mo) of the inversion stage, the solution ensures effective control and stable system. The simulation results are conducted to validate the proposed control strategy.

Speed Tracking of Indirect Field Oriented Control Induction Motor Using Neural Network

In this paper, a new approach has been proposed to control induction motor drives using a PI controller. The induction motor drive system is fed by a current-controlled voltage source inverter (VSI) and indirect field oriented control (IFOC) method has been used to control the three-phase command currents. During simulation proccess, the stator three-phase real currents are sensed from sensors inside the motor and regulated by hystersis controllers with comparison of the command currents obtained from the block proceeding the IFOC. The PI controller presented in this paper, has improved stability of the induction motor drive effectively. A neural network has been designed as a numerical controller to replace the original PI based cotroller to verify the results gained from the simulink.

In this paper, a novel multi-objective optimization method based on a Genetic-Fuzzy Algorithm (GFA) is proposed. GFA is applied to optimize the five PI controller gains in the Indirect Field Oriented Control (IFOC) of an induction motor drive. The PI controller gains are designed to optimize the step response of the system. Rise-time, maximum over-shoot, settling time and steady state error are the objective functions. In this drive system, the simultaneous estimation of the rotor speed and time constant for a voltage source inverter-fed induction motor is discussed. The theory is based on the parallel Model Reference Adaptive Control System (MRAC). The vector control of the induction motor may be achieved in the rotor-flux-oriented frame. Furthermore, to eliminate the offset error caused by the change in the stator resistance, a fuzzy resistance is also designed. The simulation results of the new method for induction motor speed control is compared with the results obtained by the conventional method, which allows better performance.