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Highly integrated and efficient electric drive technology for improving the comprehensive performance of electric vehicles stands as a prominent research focus. This paper proposes a novel dual-motor coupling electric drive axle incorporating torque vectoring (TV) technology, aiming to enhance driving maneuverability and further improve vehicle efficiency. Firstly, the configuration of the dual-motor coupling drive-axle is analyzed, introducing its four operational modes: main drive motor independent drive mode, TV motor independent drive mode, dual-motor torque coupling drive mode, and torque vectoring drive mode. Subsequently, to unlock the energy-saving potential of the dual-motor coupling drive system, optimization of the drive-mode division is conducted. This optimization selects the work mode with minimal energy consumption under the specified speed and torque requirements. The switching logic thresholds for optimal work mode boundaries and their buffer zones, designed to mitigate frequent switchover, are established in the equivalent external characteristic map of the dual motors. Finally, the co-simulation validates the torque vectoring function and driving economy. Results indicate that positive or negative torque vectoring can be strategically employed to enhance driving maneuverability or stability, respectively. The optimized multi-mode driving of the proposed dual-motor coupling electric drive-axle demonstrates a reduction in energy consumption by 7.28%, 7.35%, and 8.54% under NEDC, FTP-75, and CLTC work conditions, respectively, in comparison with a single-motor drive-axle with equal total power.

This paper proposes a novel seven-dimensional fractional-order chaotic system applied to secure communication. First, a seven-dimensional fractional order system is constructed by selecting an arbitrary fractional order q. Then, the chaotic and non-chaotic dynamic behaviors of the system are analyzed by 0–1 Test, and the correctness is verified by phase diagram comparison and complexity analysis. Then, the corresponding fractional-order chaotic circuit is designed, and the phase image which is basically consistent with the experimental simulation results is obtained. Finally, the seven-dimensional fractional-order chaotic system is used to complete the signal encryption and decryption test to achieve secure communication. This indicates that the seven-dimensional fractional-order chaotic system proposed to this paper has more complex dynamic characteristics and can be used for secure communication.

To establish the hydro-pneumatic suspension model more accurately and better analyze the influence of heavy vehicle hydro-pneumatic suspension system on road friendliness, the fractional order theory is applied to modeling, and the mathematical model and dynamics model of dual-chamber hydro-pneumatic suspension with fractional order are established by using Matlab/Simulink, and the fractional order differential term of the suspension system is calculated according to the improved Oustaloup filter. The effect of fractional order on suspension stiffness, damping and output forces is also investigated. The optimal fractional order is determined to be 0.9 for the design of a combined suspension performance index function. The vibration law of increasing amplitude and error of fractional-order is obtained through simulation, and the model with fractional-order is described more accurately. A sliding film variable structure controller was established for control. The simulation results were analyzed by means of theoretical road damage factors and dynamic load factors. The results show that the suspension system model with fractional order terms can effectively reduce the dynamic tire load and improve the suspension smoothness and road friendliness.

For the sake of deriving the signature frequencies of the composite malfunctions of broken and worn teeth of gearbox, the essay raised a method on account of local mean decomposition and Hilbert demodulation to diagnose gearbox composite fault. The local mean decomposition translates a complicated multi-component AM-FM signal into several PF elements with certain physical significance. Every PF component can be approximately regarded as a simplex component AM-FM signal. Using correlation coefficient method, the Hilbert envelope demodulation spectrum is analyzed by selecting the PF component which is strongly relevant to the incipient composite malfunction signal, and the malfunction signature frequency is identified from the demodulation spectrum. Through analyzing the emulation signal and the vibration signal of the actual gear box broken-wear complex fault, and compared with EMD, it is shown that the means can effectually discern the malfunction characteristic frequency in the composite fault signal.

In order to accurately track the state of the doubly fed induction generator (DFIG) for wind power systems and implement its fault detection, an event-triggered sliding mode observer based on particle swarm optimization (PSO-ET-SMO) is proposed in this paper. First, the sliding mode observer (SMO) is designed according to the rotor current state space equation of the DFIG. Then, a new event-triggered mechanism (NETM) is proposed for the designed SMO, and the constructed fitness function is optimized by using Particle Swarm Optimization (PSO) algorithm, so as to obtain the optimal parameters of the SMO. Finally, to verify the effectiveness of the proposed method in this paper, the fault detection of the DFIG for wind power systems is performed by using the sequence of residuals between the rotor current output values and the sliding mode observations. The innovation of this work is that a NETM is designed by combining sliding mode reaching law, and this mechanism is introduced into the design of SMO. The simulation results show that the proposed method not only reduces sliding mode chattering, but also improves the tracking effect of SMO and detects faults accurately. At the same time, due to the action of the NETM, the transmission burden between the SMO and the DFIG is also reduced.

In this article, a fault detection method based on chaos is proposed for doubly fed induction generator (DFIG). First, the nonlinear differential equation of the DFIG is established by the stator flux-oriented vector control method, and then, the motion state of the DFIG is proved by the 0–1 test algorithm. Second, the motion state of the DFIG is analyzed under normal and fault conditions. Due to some failures that may occur in the normal operation of the DFIG, the motion state of the DFIG system may enter chaos from the cycle, which is mainly manifested by the violent oscillation of the rotor current and speed. At this time, the system is in an extremely unstable operating condition. Thereby, a new sliding mode control rate is mentioned to suppress chaotic behavior. Its stability is analyzed by constructing the Lyapunov function to ensure that the system state can quickly and stably converge to the given value. After that, the simulation model of the system is built. The simulation results show that sliding mode control can make the DFIG get out of the chaotic state quickly. And, the sliding mode control has the characteristics of fast fault elimination and high control accuracy. In addition, the traditional sliding mode approach rate is compared with the proposed new sliding mode approach rate. It proves that the proposed new approach rate can achieve better control effect.

To improve the ride comfort of wheeled armored vehicles, air springs are used. To describe the vehicle motion more accurately, a nine-degree-of-freedom air suspension system for the whole vehicle was established, and its equations of motion were derived. Through theoretical analysis of the stiffness characteristics and forces on the air springs, the nonlinear restoring force was obtained as a cubic polynomial of the air spring displacement. The simulation results obtained by fitting the polynomial and radial basis function curves with MATLAB/Simulink software are consistent with the actual test results, thus verifying the correctness of the nonlinear air spring polynomial model. Finally, a fuzzy fractional order PIλDμcontroller is designed and simulated for the vehicle-seat-body model in terms of wheel dynamic load, suspension dynamic deflection, body acceleration, and other indicators. The simulation results show that the fuzzy fractional order PIλDμProportion Integral Differential (PID) control strategy has better overall performance than the PID control strategy, fuzzy control strategy, and fuzzy PID control strategy.

In-wheel motor-drive electric vehicles have the advantage of independently controllable wheel torque and the disadvantages of unsprung mass rise and power restriction. To address the disadvantages, a centralized layout electric torque vectoring drive-axle system (E-TVDS) with dual motors is proposed, which can realize arbitrary distribution of driving torque between the left and right wheels. First, the speed and torque distribution principle of E-TVDS based on velocity diagram are analyzed, and a virtual prototype of the whole vehicle with basic gear ratio relation model of the E-TVDS is built for simulation to verify the theoretical results and the basic effect of E-TVDS on the steering performance of the vehicle. Second, the characteristics of 36 types of the novel E-TVDS topology structure are compared and analyzed, and the optimal structure scheme is selected. Third, the accurate multiple degrees of freedom dynamic model for the optimal structure is established by using the bond graph method, and its dynamic response characteristics are analyzed. The results show that the vehicle equipped with the proposed E-TVDS can distribute the driving torque with the almost identical amount but opposite sign between the left and right wheels in any direction, and varying amount according to different chassis dynamics control requirements, and the torque response performance is great with little delay and overshoot. The function and dynamic response of the proposed E-TVDS show that it has potential application value for various performance improvements of electric vehicles.

This paper proposes a novel chaotic system model, which can be in a chaotic state when the order is fractional-order, integer order and improper fractional-order. Analyze the equilibrium stability and dynamic characteristics of the chaotic system employing the bifurcation diagram, maximum Lyapunov exponent, Spectral Entropy complexity and phase diagram. The outstanding randomness and unpredictability of system is discovered, which is suit for digital circuit secure communication. The Chaos Shift Keying secure communication method is used to encrypt and decrypt the data with the sequence of system in improper fractional-order, and the sequence of system in integer order is used as cipher. Apply to electronic lock, the simulation results illustrate that the method has an excellent encryption effect and can decrypted, which effectively improves the security of electronic lock confidential communication.

Compared with the static cipher, the dynamic cipher has the characteristic of "one cipher at a time" proposed by Shannon theory. Therefore, it is regarded as the safest among many forms of identity authentication. This paper proposes a five-dimensional chaotic system suitable for the construction of dynamic cipher and analyzes its relevant characteristics, including stability, balance, time-domain waveform, Poincaré cross sectional diagram, Lyapunov exponent and bifurcation diagram. The results show that the chaotic system has multiple controllable parameters and a wide range of chaos, which is very suitable for constructing chaotic dynamic ciphers. The complexity of the proposed chaotic system is analyzed to verify the high security of the proposed system. On this basis, a dynamic cipher electronic lock based on chaotic system is designed in this paper. In the designed hardware circuit, the fourth order Runge–Kutta solving algorithm is used to discretize the constructed system, and the chaos is successfully implemented in the single-chip microcomputer. The phase diagram obtained from the circuit simulation data is basically consistent with the numerical simulation. Finally, the circuits of the handheld terminal and the electronic lock terminal are designed and simulated. The simulation results show that the preset function can be basically realized, and the generated chaotic dynamic cipher is random and irregular. The five-dimensional chaotic system proposed in this paper has complex dynamic characteristics, which makes the dynamic cipher electronic lock based on the chaotic system extremely safe.

Following the establishment of the draft standardization for Post-Quantum Cryptography (PQC), cryptographic systems across various sectors have undergone a paradigm shift. Although the theoretical strength of PQC has provided a robust foundation for securing communications against quantum threats, physical implementations of PQC algorithms remain vulnerable to Side-Channel Attacks (SCAs). Existing SCA studies predominantly focus on the attack process, lacking thorough side-channel leakage assessments and comparisons of inherent vulnerabilities at different attack points and with different countermeasures. In this paper, we first present a comprehensive assessment of side-channel leakage and resistance of four attack points within an ARM Cortex-M4 implementation of Kyber, including its masked version. This assessment employs a range of countermeasures such as noise addition, random delays, clock jitter, and their combinations. Besides, we also build deep-learning models for attacking, thereby verifying the results of the leakage assessments. By collaboratively utilizing three distinct leakage assessment approaches and deep learning-based attack results, we experimentally demonstrate that different algorithmic intermediate values of Kyber are suited to different countermeasures, which advances our understanding of the capacity and vulnerability of PQC implementations.

Electrical Parking Brake (EPB) has been popularly used in passenger cars over the past ten years. With the help of the several kinds of sensors mounted in driveline for the total traction force estimation, EPB can obtain well performance on drive-off assistance and automatic parking brake. Furthermore, its AUTOHOLD function can realize automatic parking brake and ease the driver. However, given that the higher cost and complexity of this traction force estimation method based on the driveline sensors and its slower response resulted by applying maximum parking force for safety parking while driving off, a novel automatic parking brake system without these transmission system sensors, such as clutch position sensor for the cars with manual transmission, is proposed in this paper, including its control scheme and application test. Firstly, the indirect judgement method of the appropriate moment to release the parking brake, which is based on the car pitch moment when it drives off, is introduced according to the force analysis when the car is ready to go. Then a pragmatic mass estimation method for proper brake force calculation is proposed for improving the drive-off performance. In addition, for the convenience and drivability of skillful driver, as well as the system reliability, a mechanical redundant design to reserve the conventional handbrake lever is also described. Finally, various simulations based on CarSim software and road tests are performed to validate its effectiveness.

Although electric vehicle fully exhibits its comparative merits of energy conservation and environmental friendliness, further improvement of its traction energy efficiency lacks comprehensive investigations in the past. In this paper, the effect of the torque vectoring on traction energy conservation during cornering for a rear-wheel-independent-drive electric vehicle is investigated. Firstly, turning resistance coefficient and energy conservation mechanism of torque vectoring are derived from the single track dynamic model. Next, an optimal torque vectoring control strategy based on genetic algorithm is proposed, with the consideration of the influence of the operation-point change of the in-wheel motors, to find out the best torque vectoring ratio offline. Finally, various simulation tests are conducted to validate the energy conservation effect after Simulink modelling. The results verify that though the optimization of the operating region of the motors is the main part for tractive energy conservation, the contribution of torque vectoring itself can reach up to 1.7% in some typical cases.

In this paper, we are going to introduce a novel iteractive method, leading us to find the fixed point of a nonlinear function based on firefly algorithm. This new method is able to help us in solving nonlinear function more efficiently. In addition, some theorems will be obtained by using firefly algorithm. Lastly, we are going to prove the validity of the proposed technique through some complicated functions as well.