In this paper, a novel time-domain algorithm for long transmission line distance protection is proposed. When a certain fault occurs, the current and voltage at the end of the protection zone can be calculated by usin...
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In this paper, a novel time-domain algorithm for long transmission line distance protection is proposed. When a certain fault occurs, the current and voltage at the end of the protection zone can be calculated by using the measured current and voltage at the relay. By applying the new algorithm, which has three coefficients needed to be resolved by time-domain differential equation and fits long distance transmission line, to the current and voltage data at the end of the protection zone, we will obtain the fault distance. When the computed distance is less than the setting value, we consider the fault as an internal fault. Theoretical analysis and simulation prove that this method is not affected by the distributed capacitance or aperiodic component. Furthermore, the algorithm works very reliably without overreaching and its speed is really fast. As to a 300km long transmission line with a 300Ω transition resistance, this algorithm is verified to be valid and accurate.
A novel model-predictive-control strategy with a timeout scheme and p-step-ahead state estimation is presented in this paper to overcome the adverse influences of stochastic time delays and packet losses encountered i...
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ISBN:
(纸本)0780390989
A novel model-predictive-control strategy with a timeout scheme and p-step-ahead state estimation is presented in this paper to overcome the adverse influences of stochastic time delays and packet losses encountered in network-based real-time control. An open-loop unstable magnetic-levitation (maglev) test bed was constructed and employed for its experimental verification. The compensation algorithms developed in this paper deal with the network-induced stochastic time delays and packet losses in both the forward path and the feedback path simultaneously. With the p-sampling-period delay upper bound, the networked control system (NCS) can also accommodate up to p - 1 successive packet losses. Experimental results demonstrate the feasibility and effectiveness of this networked real-time control strategy.
The LNG shipbuilding profiles' deformation leads to lots of challenges for hi-precision shipbuilding, in order to achieve hi-precision manufacturing for deformed LNG shipbuilding profiles, a 3D-compensating algori...
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The LNG shipbuilding profiles' deformation leads to lots of challenges for hi-precision shipbuilding, in order to achieve hi-precision manufacturing for deformed LNG shipbuilding profiles, a 3D-compensating algorithm for shipbuilding profile deformation is developed based on the profile deformation happening principles. The spatial coordinates on edge curve of the profile are measured and collected by a moving 2D laser sensor. Basing on the collected profile edge coordinates, a formula of polynomial curve is defined and fitted by the method of least squares, which takes accumulated chord length as parameters. Giving coordinates on a standard profile, the target coordinates on deformed profile can be calculated, eventually the deformation of the profile is compensated and the hi-precision manufacturing for deformed shipbuilding profile is fulfilled. Furthermore, the compensation algorithm has been has been used in a robot flexible cutting system for serial production a famous shipbuilding company. The results show the 3D-deformation of shipbuilding profiles robot cutting system worked as expectation, it also verified the algorithm is effective and efficient.
AMOLED displays are still facing the two major challenges after one decade of intensive researches. They are low yield particularly for large panels and modest lifetime due to image sticking. The low yield issue is ca...
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AMOLED displays are still facing the two major challenges after
one decade of intensive researches. They are low yield
particularly for large panels and modest lifetime due to image
sticking. The low yield issue is caused by the analog driving
scheme and the image sticking issue is due to the active emitting
nature of OLED. With digital driving scheme, the yield of
AMOLEDs can be lifted to the level of LCDs. On the other hand,
the image sticking issue is getting even severer. It is caused by
both, OLED I–V drift and its efficiency loss. In this paper, a
method based on aging model is shown which compensates the
reduced efficiency of aged OLED pixels. Image sticking artifacts
can be deferred and the lifetime of an AMOLED display can
significantly be extended. It may ease the penetration of
AMOLEDs in TVs and automotive displays performing the high
image quality of AMOLEDs with even longer lifetime.
This paper handles further development of a proposed combined PAM and PWM driving scheme for Micro-LED displays. A prototype display which consists of 64x3x64 pixels is driven by a combined PAM and PWM scheme. The occ...
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This paper handles further development of a proposed combined PAM and PWM driving scheme for Micro-LED displays. A prototype display which consists of 64x3x64 pixels is driven by a combined PAM and PWM scheme. The occurring non- uniformity of Micro-LED displays is improved by two extensions in the driving scheme. First, an analog bit for high luminance compensation and second, a compensation method that uses the high gray scale of digital driving schemes.
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