Search

Aluminum target material is an important target material and is widely used in preparations of semiconductor films, integrated circuits, display circuits, protective films, decorative films, etc. In this study, pure aluminum coatings were deposited on stainless steel substrates by cold-spray technology as part of an overall project to produce large-size pure aluminum sputtering target materials. The results show that pure aluminum coatings exhibit high adhesive strength (~98 MPa), high deposition efficiency (~95%), and low porosity (~0.3%) on stainless steel substrates. The bonding mechanisms of pure aluminum coatings on stainless steel are a combination of metallurgical and mechanical interlocking. The evolutions of microstructure and mechanical properties of pure aluminum coatings under different heat treatments were also studied. With the increase of heat treatment temperature, it is found that cold-sprayed aluminum coatings become more homogenous in microstructure, the microhardness is reduced, and the adhesive strength seems to be slightly reduced. Overall, this study demonstrates significant advantages of cold-spray technology in depositing high-performance pure aluminum coatings on stainless steels.

A unified specification to design and operate the stability control device in smart substation has not been formed yet, which has greatly affected the promotion and application of stability control device in smart substation. Thus, referring to the technical specifications of protection device and combining to the specificity of stability control device, a full and detailed configuration scheme is proposed to meet the requirement, including the device configuration principle, the access configuration of SV and GOOSE for variable primary connection types, the virtual terminal and soft switch. This solution is beneficial to standardize the R&D of stability control device in smart substation, and to facilitate on-site debugging, operation and maintenance.

In order to improve the throughput of network and ensure the quality of user experience, more small stations has been densely deployed in cellular networks. And consumption of fossil fuel will increase rapidly, which has brought serious challenges to the mobile operators in cost control and the ecological environment. With the development of renewable energy and smart grid, great changes have taken place in energy structure and energy utilization of the cellular network. The future trend of cellular networks will present a multi-source power. Traditional grid as the main body, centralized powering the base station form the wide area power grid, to maintain the basic power of wireless network. As a supplement, green base station can combine the set of equipment, base station, storage battery and charge controller together to achieve micro electric power network by multi-sources energy harvesting technology. However, the harvest of the renewable energy is influenced by the time-space instability. The demand of users and the consumption of the cellular networks are also influenced by space-time instability. Therefore, this paper proposes a model of the flexible configuration of energy through the energy management unit(EMU), through energy cooperation between base stations and smart grid, we can get optimal energy configuration. By analyzing the scenario of N time slots, m base station, we solve the optimal energy profiles for each time slots according to the greedy algorithm and Linear programming, and then the relevant simulation will validate the algorithm. By using the algorithm to realize the energy cooperation according to the demands of each node, we can recede the instability of the process of energy harvesting. And we can achieve the goal of optimizing the efficient use of clean energy.

An optimal coordinated control strategy between generator and VSC HVDC system is proposed in this paper. In the studied system, a generator is connected with infinite bus through parallel AC lines and VSC HVDC. The simulation results show that both the generator and the VSC HVDC system can be recovered rapidly from minor or severe disturbance, and the control strategy is robust to the parameter variety of power system. Simulation are also conducted when the generator and VSC HVDC system are controlled independently. The simulation results also show that the system has much better dynamic responses with the proposed coordinated control strategy than that with the independent control