Maximum Torque Control Research Articles

Maximum Torque Control of 3-phase induction motor drives

Maximum Torque Control of 3-phase induction motor drives

CONTROL STRATEGY FOR REGENERATIVE BRAKING IN ELECTRIC VEHICLES

Regenerative Braking system (RBS) is energy recovery process that will slows-down a moving vehicle by converting its kinetic energy into electric energy that can be either use immediately or stores until it is needed. Regenerative braking provides an effective way of extending the driving range of battery powered electric vehicles (EVs). It approaches an analysis of maximum torque control distribution of an electric vehicle for BLDC motor with traction on wheels. This work proposes a Direct Torque Control (DTC) strategy to improve the performance of distributed torque applied to electric vehicles to act during regenerative braking. In this model FUZZY controller for BLDC motor is used and is compared with PI controller. The proposed work will be carried out using MATLAB/Simulink software. Key Words: Regenerative Braking, Fuzzy logic control, bi directional DC-DC converter, Direct Torque Control (DTC) method.

Inductionless control of high speed permanent magnet synchronous motor in full speed range based on neural network

In order to solve the problems of high control error, large maximum output torque and long control time in the traditional full speed range sensorless control method of high-speed permanent magnet synchronous motor, a full speed range sensorless control method of high-speed permanent magnet synchronous motor based on neural network is proposed in this paper. Analyze the range of stator current trajectory in rotor coordinate system, so as to build the discrete model of permanent magnet synchronous motor, and build the whole process control model of high-speed permanent magnet synchronous motor by using neural network algorithm. Through the design of observer, overall control structure and speed regulation range of non inductance control, the goal of non inductance control in the full speed range of high-speed permanent magnet synchronous motor is achieved. The experimental results show that the non inductive control error in the full speed range of the high-speed permanent magnet synchronous motor is 0.2, the maximum output torque is 420 N⋅m, and reaches 2000 r/min at 0.6 s. The practical application effect is good.

Optimized Anti-Windup Coordinating Strategy for Torque-Maximized High-Speed Flux-Weakening Operation of Constrained Induction Motor Drives

Due to the contradiction between torque-maximized requirements and limited voltage and current constraints, voltage closed-loop flux-weakening strategy is developed to circumvent the saturation problem for maximum torque control of induction motor when the accelerating speed enters high-speed region. At the same time, since voltage inconsistency caused by the saturation is employed to construct flux-weakening controller (FC), anti-windup (AW) item in current regulator needs to be cut off to avoid the conflict. However, the replacement discards part of AWs utility and results in the distortion of command voltage, thus compromising system’s dynamic performance and making the tuning process of proportional-integral controller (PI)-based FC much trickier. To address this issue, an equivalent saturation model is presented. An optimized AW coordinating strategy is proposed, combining a novel structure, so-called virtual voltage buffer, with FC. Through an equivalent proof, it can be transformed into over-modulation block for a convenient implementation. Through its compensation in the transient period, <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$d$ </tex-math></inline-formula> -axis current can be quickly and smoothly manipulated in a more concise tuning process. As a result, the overall system possesses a fast acceleration capability with maximum torque and a wide speed range, while retaining a desirable system response. Simulation and experimental results verify the effectiveness of proposed method.

Harmonic and Vibration Analysis of Dual Three-Phase PMSM with One-Phase Open Circuit Fault

This paper analyzes the harmonics and vibration under different fault-tolerant current control when one-phase winding of dual three-phase permanent magnet synchronous motor (PMSM) is an open circuit fault. Firstly, the dual three-phase load condition subdomain model of breadloaf surface-mounted permanent magnet (PM) PMSM is established. Secondly, the working conditions of an open circuit fault of one-phase winding are set from the perspectives of no fault-tolerant (NFT) control, maximum torque (MT) control, minimum copper loss (MCL) control and single three-phase mode (STPM) control. The torque harmonics and electromagnetic force harmonics of the four working conditions are analyzed. Then, considering the multi-physical field of electromagnetic and structural coupling, the electromagnetic force in the motor air gap acts on the stator core, and the vibration under four different working conditions is calculated and analyzed. Through the comparison between the analytical method and finite element method, the accuracy of the established model is verified. The calculation method is effective and accurate, it can quickly predict the motor performance in case of one-phase open circuit fault of dual three-phase PMSM.

Research on IPMSM Control Based on MTPA

In view of the lack of the role of reluctance torque in the electromagnetic torque output of the motor under the previous control logic with id=0, only the excitation torque component is working. Therefore, on the premise of inputting unit current, the output electromagnetic torque cannot reach the maximum value, resulting in low energy utilization, reduced load capacity and low operation efficiency. The maximum torque control of unit current output is proposed to control id to pursue the maximum torque. This control method studies the mathematical model of the Interior Permanent Magnet Synchronous Motor (IPMSM) in the rotating d-q-O coordinate system, and establishes the relationship between the current and torque of IPMSM through mathematical formula derivation, so as to realize the Maximum Torque Per Ampere (MTPA) control of the IPMSM. Through Simulink simulation, compared with the previous control logic with id=0, when MTPA control logic outputs the same electromagnetic torque value, the stator current value of IPMSM is smaller and the energy utilization rate is the highest, thus improving the operation efficiency.

Research and Analysis of Permanent Magnet Transmission System Controls on Diesel Railway Vehicles

As the energy crisis and environmental pollution continue to be a gradual threat, the energy saving of transmission systems has become the focus of railway vehicle research and design. Due to their high-power density and efficiency features, permanent magnet synchronous motors (PMSM) have been gradually applied in railway vehicles. To improve the efficiency of the transmission system of diesel railway vehicles, it is a good option to use PMSM as both a generator and traction motor to construct a full permanent magnet transmission system (FPMTS). Due to the application of the new FPMTS, some of the original control strategies for diesel railway vehicle transmission systems are no longer applicable. Therefore, it is necessary to adjust and improve the control strategies to meet the needs of FPMTS. We studied several key issues that affect the reliability and comfort of the vehicles. As such, this paper introduced the FPMTS control strategy, including the coordinated control strategy of the diesel and the traction motor, the two degrees of freedom (2DOF) decoupling current regulator, the maximum torque control of the standardized unit current, the wheel slip protection control, and the fault protection strategy. The experiment was carried out on the test platform and the test run of the diesel shunting locomotive equipped with the FPMTS. The results showed that the control strategy described in this paper met the operation characteristics of the FPMTS and that the control performance was superior. The study of FPMTS lays the foundation for the subsequent application of permanent magnet motors in high-powered diesel locomotives and high-speed diesel multi-units.

Fault-Tolerant Hybrid Current Control of Dual Three-Phase PMSM With One Phase Open

A fault-tolerant hybrid current control is proposed for dual three-phase permanent magnet synchronous machines (PMSMs) with one phase open in this article. The maximum torque control, minimum copper loss control, and single three-phase mode control are unified in the proposed method, which is a combination of single three-phase mode control and maximum torque control with different percentages. When the percentage of single three-phase mode control ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$k$ </tex-math></inline-formula> ) varies from 0% to 100%, the hybrid current control transitions from maximum torque control ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$k \,\,=0$ </tex-math></inline-formula> %) to minimum copper loss control ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$k\,\,=50$ </tex-math></inline-formula> %) and then to single three-phase mode ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$k =100$ </tex-math></inline-formula> %). Therefore, the hybrid current control can be switched among the aforementioned three control methods easily and smoothly. Meanwhile, it can be a mixed mode with a tradeoff between the maximum torque control and the minimum copper loss control, such as the minimum copper loss control for a given torque within the full torque range, which can be achieved by changing <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$k$ </tex-math></inline-formula> . The smoothness of transition among the maximum torque control, minimum copper loss control, and single three-phase mode control is verified by experimental results on a prototype machine.

Analytical low-jerk reorientation maneuvers for multi-body spacecraft structures

A low-jerk attitude guidance method is developed, based on an analytical smoothing of a bang-off-bang maneuver. A set of closed-form equations are derived and used to plan constrained low-jerk maneuvers, with prescribed boundary conditions, inertia, time and maximum control torque. The guidance law is first developed for one-dimensional and then three-dimensional rotations using two different approaches: (i) by designing a rotation about the Euler axis and (ii) by using the inverse kinematics equations. A generic model of the torque induced by a multi-body appendage is derived using the lumped-parameter method. This method can also be used to approximate the dynamic behavior of flexible appendages. The simulations results show that the smoothing techniques reduce the excitation of multi-body and flexible structures during a slew maneuver.

Optimization of maximum torque output in the wide speed range of a PMSM traction control system

This paper introduces a permanent magnet synchronous motor maximum torque control method for the wide speed range of a traction control system. This method tracks the maximum torque per ampere operating point and generates a d-axis current command according to the injection of a high-frequency angle signal to the current. This method is parameter independent when looking for the maximum torque per ampere operating point. By not injecting any real signal to a permanent magnet synchronous motor, this method does not increase the amount of copper and iron losses resulting from real signal injection. To obtain a maximum torque output in a wide speed range, this method considers the maximum amplitude limits of voltage and current when the traction motor runs in a flux weakening control field. This method is also robust to current and voltage harmonics, speed mutations, and torque disturbances. Experiment and analysis are conducted on a permanent magnet synchronous motor traction control system prototype under various operating conditions to verify the effectiveness of this method.

Position and MTPA Current Phase Estimation Method at Low Speed for IPMSMs Based on Flux Model Suitable for Maximum Torque Control

Position and MTPA Current Phase Estimation Method at Low Speed for IPMSMs Based on Flux Model Suitable for Maximum Torque Control

Research on Active Disturbance Rejection Control Technology of Electromechanical Actuators

It has been proven that the properties of non-linearity, multi-disturbance, and time-variation are the main factors affecting the performance of the electromechanical actuator (EMA) for guided artillery rockets. In particular, its controller should have good dynamic characteristics and strong anti-disturbance features when the projectile is maneuvered at the end of its guidance. For these reasons, an active disturbance rejection controller (ADRC) was designed for a guided artillery rocket’s EMA with a ball screw drive. Compared to other control methods, it has been shown that the ADRC had a stronger disturbance rejection ability than PID, Fuzzy-PID, and BP-PID under the condition of 20% maximum control torque disturbance, and it also had a large stability margin and bandwidth.

Dynamic DC-link Voltage Adjustment for Electric Vehicles Considering the Cross Saturation Effects

The demands of remarkable reliability and high power density of traction systems are becoming more and more rigorous. The conflicting requirements imposed on the control strategy are higher accuracy and higher efficiency over the whole speed range. However, parameter variations caused by the cross coupling and magnetic saturation effect (omitted from the cross saturation effects in the following) are usually neglected in conventional control strategies, which could reduce the control precision. In order to fully consider the influence of parameter changes on the motor control and derive an approach that could realize the maximum efficiency during the whole speed range, this paper proposes a dynamic DC-link voltage adjustment strategy considering the cross coupling and magnetic saturation effects. The strategy can be categorized into three parts. Firstly, the torque request is transformed to the optimal current reference signal. Secondly, the differences between the setpoint and the real-time feedback signals of torque and voltage can be applied in the linearized function in the did,q coordinate. The solution guides the current vector into the optimal direction under the current and voltage limits to ensure the safety and reliability of the motor. Finally, last, the bus voltage can be modified according to the asked terminal voltage. A 10 kW prototype which instrumented a bidirectional DC-DC converter to regulating the bus voltage has been studied. The simulation and experiment results verify that the proposed control strategy can reduce the inverter losses in low speed region by offering the low bus voltage and track the actual maximum torque control trace more accurately, meanwhile, the flux weakening region can be delayed in high speed region by applying a high bus voltage. It helps the motor realize the high utilization rate of the DC-link voltage and guarantees the system reliability and robustness.

Adaptive Neuro Fuzzy Based Maximum Torque Control of Three Phase Induction Motor

Adaptive Neuro Fuzzy Based Maximum Torque Control of Three Phase Induction Motor

Study on a Maximum Torque Control of Magnetic-Geared Motors

Traction motors of EVs require wide power band characteristics. A magnetic-geared motor has a possibility to achieve these requirements because it has passively variable magnetic flux characteristics. In this paper, the passively variable magnetic flux characteristics of the magnetic-geared motor is investigated using finite element analyses. Furthermore, a maximum torque control method for the magnetic-geared motor is proposed and investigated.

동기릴럭턴스전동기의 자기포화를 고려한 약계자제어

Conventional field weakening control considering magnetic saturation in a 3-phase synchronous motor drive has not presented a clear calculation method for base speed. In this paper, a calculation method for the base speed considering the magnetic one is presented. The base speed is calculated using maximum torque control method. It is shown that the improved speed response is achieved by the proposed method being compared to that of the conventional method. In addition, it is shown that voltage limit curve with magnetic saturation does not become ellipse while the one without magnetic saturation becomes ellipse. The proposed method is verified by simulation results.

Investigation and implementation of a new hybrid excitation synchronous machine drive system

Hybrid excitation synchronous machines (HESMs) inherit the high-torque density of permanent magnet synchronous machines and flux regulation capability of wound rotor synchronous machines. This makes HESMs attractive candidates for vehicle traction applications. To further improve torque density, an optimised HESM with magnet shunting rotor is proposed in this study. This study presents a maximum torque control strategy with zero d-axis current. Furthermore, an optimised control strategy that utilises the coordinated operation between the field current and d-axis current is proposed. The optimised control strategy exhibits advantages of low-speed high-torque, wide constant power range, and high efficiency in flux-weakening (FW) region. A 100 kW drive system based on the optimised HESM with the proposed control strategy is developed, experimentally realised, and validated. The experimental results show that the FW range is 3.5–1, and the efficiency of the drive system is >92% in most operating region, which verify the superiority and effectiveness of the proposed HESM drive system.

最大トルク制御軸での仮想インダクタンスを用いた永久磁石同期モータ用直接トルク制御の広範囲運転制御法

最大トルク制御軸での仮想インダクタンスを用いた永久磁石同期モータ用直接トルク制御の広範囲運転制御法

Attitude control of apricot during orientation transmission

The kinetic characteristics of apricots during orientation transmission were studied to provide a basis for improving the structure of the transmission device. Previous studies have generally focused on the development of orientation devices, but few studies have been conducted to analyze the mechanisms of orientation. In order to study the attitude control in the orientation mechanisms, an orthogonal combination test was performed and a rigid kinetic model for a monosymmetric apricot was developed based on Euler’s kinetic equations with the modified Rodrigue parameters (MRPs). Kinetic simulation and analysis based upon the attitude control law were conducted and an attitude control simulation platform was created. The simulation results showed that the orientation transmission system for monosymmetric apricots was globally convergent and tended to stable. The experimental torques also affected the orientation success rates. The calculated average experimental torque value (0.164 N•m) was consistent with the maximum control torque value (0.16478 N•m) when the system was in a stable state in Simulink. The consistency between the simulation result and the calculated control torque validates the correctness of the designed control torques. Keywords: attitude control, apricot, orientation transmission, torque control, monosymmetric fruit DOI: 10.3965/j.ijabe.20160905.2135 Citation: Ding X Y, Wang C Y, Huang C Y, Luo J Q. Attitude control of apricot during orientation transmission. Int J Agric & Biol Eng, 2016; 9(5): 9－16.

Three-axis attitude stabilization of a flexible satellite using non-linear PD controller

In this paper, after complete modelling of a flexible satellite equipped with a control moment gyroscope (CMG) actuator, it is shown that a PD-like controller can globally asymptotically stabilize this satellite by using Lyapunov’s direct method. Despite the simplicity, simulations show that the controller can stabilize the flexible satellite in a three-axis manoeuvre even in the presence of external disturbances. Then, using a non-linear variable gains PD controller, which only uses angular velocity of the rigid body and the attitude parameters as the inputs, the performance of the control system is improved in some important aspects such as reducing maximum control torque, reducing maximum peak of deflection of the appendages and increasing robustness of the controller against the orbital disturbances. In addition, locally asymptotically stability of the non-linear variable gain PD controller is guaranteed using a novel Lyapunov candidate function. Considering the difficulty in measuring the appendages’ deflection and the primarily existence of parameter uncertainties, and as this controller is independent of changes in these parameters, such a control system is very useful and applicable. In order to validate the system’s mathematical model and the control system performance, an exact model of the satellite is constructed in the ADAMS/View software that is linked to the MATLAB software. The efficacy of the proposed approach is demonstrated by several numerical examples.