Reinforcement learning (RL) has gained significant attention due to its end-to-end learning capabilities and model-free nature. In the realm of vehicle engineering, active suspensions are crucial for enhancing both comfort and safety. The Deep Deterministic Policy Gradient (DDPG) algorithm, characterized by its stability and efficiency, offers valuable guidance for addressing the nonlinear issues in suspension systems. However, its learning efficiency may be compromised when dealing with high-dimensional state or action spaces. Therefore, this research primarily focuses on improving the DDPG algorithm by implementing enhancements by improved reward modules and integrating Long Short-Term Memory (LSTM), in order to maximize its control performance. By conducting five sets of experiment, the results demonstrate that the DDPG algorithm, after being integrated with various methods, exhibits superior control performance.

A medium/high-power conversion system, using power electronic (PE) converter in conjunction with a medium/high-frequency transformer, has many desirable effects suitably oriented for modern power system architecture. Switching at high frequency results in lesser volume of magnetics but induces higher loss density. Thus design and characterization of a medium-frequency (MF) high-power (HP) transformer has significant ramification on its performance and application. Thermal management of a MF HP transformer is one of key aspects for its characterization. In this paper, an equivalent thermal model of a multi-layer concentrated winding is derived. Core and copper losses are carefully estimated. Thermal resistance and capacitance are accurately calculated. Time-domain response of proposed thermal network is obtained using Heun's method (Modified Euler) and validated with PLECS. Effects of temperature change on thermal properties of material and coolant (transformer oil) are also discussed. Furthermore, accuracy of said thermal network is corroborated through FEM-CFD study of a 10kW, 0.5/2.5kV, 1kHz natural oil-cooled transformer. Close agreement between analytical and simulation results is observed which substantiates proposed thermal model in terms of accuracy and efficacy of computation.

The advantage of low cost and large capacity gives strong driving force for hard disk to enter the consumer electronic market. One of the most challenging servo control issue faced in mobile application is to perform normal read/write operation when significant vibration is excited in HDD jogging/walking condition. This paper presents a simple yet effective method to improvement hard disk throughput with an add-on low frequency disturbance feed forward compensator. With the proposed approach, the track following performance is significantly improved in jogging/walking, and the hard disk is capable to meet the read/write throughput requirement with minimum servo controller re-design effort

This paper deals with modeling of the hard disk ramp loading with a discontinuous controller. The property of the sampled-data system with a discontinuous hold is studied. Further, explicit expression of the discrete-time transfer function of sampled-data systems with a discontinuous hold is provided for a class of continuous time plant. It is shown that with discontinuous hold, the hard disk plant sampled-time model is minimum-phase instead of non-minimum phase if with zero-order hold