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Chen X.,Guangdong University of Technology | Chen X.,Dongguan Anwell Digital Machinery Co. | Yang M.,Dongguan Anwell Digital Machinery Co.
Key Engineering Materials | Year: 2013

Laser scribing of hydrogenated amorphous silicon (a-Si) is a crucial step in the fabrication of thin film photovoltaic modules. The required line width of the laser scribing process for a-Si thin film solar cell preparation is 30 μ m∼50μ m, the dead zone is less than 300 μ m in size, and the line depth should be compliant with the process requirements. Thus, the high imaging quality and focal depth of the optical system is required in the laser scribing system. Three crucial laser patterning steps (known as P1, P2 and P3 in the photovoltaic literature) are integrated in the thin film silicon module manufacturing sequence. Therefore, efforts to optimize these laser processes are demanded by the photovoltaic industry. In particular, the state of the remaining material after laser treatment is known to have a critical influence on the electrical properties of the final devices. This paper focuses on the P3 laser scribing process with the peculiarity that it has been done in single solar cells. By evaluating it in single solar cells rather than in finished module, it is possible to isolate its effect on the device characteristics since the P1 and P2 scribings are omitted. To study the effect of the P3 scribing length, several scribings can be done in the same cell. As it will be shown, the high speed motion systems needed for precision laser scribing plays an important role in this experiment. They can be responsible for the electrical losses after the scribing of the solar cells. If this is dealt with properly, it can be seen that the P3 scribings have very little effect on the electrical characteristics of the processed solar cells. © (2013) Trans Tech Publications, Switzerland. Source

Dongguan Anwell Digital Machinery Co. | Date: 2011-04-19

machines for manufacturing solar cells, solar modules, photovoltaic cells and photovoltaic modules. solar cells, solar modules, photovoltaic cells and photovoltaic modules. installation services for solar cells, solar modules, photovoltaic cells and photovoltaic modules. Engineering and design services in the field of solar cells, solar modules, photovoltaic cells and photovoltaic modules.

Chen X.-S.,Guangdong University of Technology | Chen X.-S.,Dongguan Anwell Digital Machinery Co. | Yang M.-S.,Dongguan Anwell Digital Machinery Co. | Liu F.-C.,Guangdong University of Technology
Chinese Control Conference, CCC | Year: 2013

In this paper we propose a new online actor-critic algorithm based on policy iteration for learning the continuous-time optimal control solution with infinite horizon cost for nonlinear systems. In other word, the algorithm solves online an algebraic Riccati equation without knowing the internal dynamics model of the system. This approach is implemented as an actor-critic structure which involves both actor and critic neural networks. Because of using a policy iteration method, the present algorithm alternates between the policy evaluation and policy update steps until an update of the control policy will no longer improve the system performance. Simulation results show the effectiveness of the new algorithm. © 2013 TCCT, CAA. Source

Chen X.,Guangdong University of Technology | Chen X.,Dongguan Anwell Digital Machinery Co. | Yang M.,Dongguan Anwell Digital Machinery Co.
Key Engineering Materials | Year: 2015

Smart actuators, such as piezoceramic actuators, magnetostrictive actuators, and shape memory alloy actuators are widely used in applications of micrositioning and vibration control. Piezoelectric (PZT) actuators having the characteristic of infinitely small displacement resolution are popularly applied as actuators in precision positioning systems. However, the tracking control accuracy of the precision positioning systems is difficultly achieved because of its nonlinear hysteresis effect. Hence, it is important to take hysteresis effect into consideration for improving the trajectory tracking performance. In this paper, in order to capture the hysteresis nonlinearity in the PZT actuators, the Hammerstein model is put to use. The fuzzy control algorithm is used to identify the weighing values. The adaptive inverse controller based on adaptive fuzzy inference is used to track the PZT actuator. We firstly identify the weighting values of the Hammerstein model in situ using the multi-mode fuzzy control algorithm based on the error between reference displacement and actual displacement of the actuator, and then calculate the weighting values and threshold values of the Hammerstein model. Finally, we obtain the feed-forward input voltage. The stability of the controller in the presence of the estimated state is demonstrated. The experimental results show the performance is effectively improved under the intelligent control method. © (2015) Trans Tech Publications. Source

Zhang S.,South China University of Technology | Zhang S.,Dongguan Anwell Digital Machinery Co. | Wang H.,South China University of Technology | Yeung M.,Dongguan Anwell Digital Machinery Co. | And 3 more authors.
International Journal of Hydrogen Energy | Year: 2013

Cu(OH)2/TNAs photocatalyst was prepared by loading Cu(OH) 2 nanoparticles on TiO2 nanotube arrays (TNAs) using a chemical bath deposition method. The amount of Cu(OH)2 loaded on the arrays was controlled by the repeated deposition times. The prepared catalyst was used to generate hydrogen under simulated solar light irradiation, and the results demonstrated that the hydrogen yield of Cu(OH)2/TNAs was 20.3 times that of the pure TNAs. Furthermore, the photocatalytic efficiency for hydrogen production decreased only 5.8% after five cycles, indicating that Cu(OH)2/TNAs photocatalyst showed excellent stability and reusability. This work presents an applicable and facile method to fabricate a highly active and stable photocatalyst for hydrogen production. © 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights. Source

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