Crystal oscillator disciplined system based on digital phase locked loop (PLL) technology, using satellite signals output 1 Pulse Per Second (1PPS) local oscillator signal tame, so as to obtain high-precision time and...
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ISBN:
(纸本)9781479943159
Crystal oscillator disciplined system based on digital phase locked loop (PLL) technology, using satellite signals output 1 Pulse Per Second (1PPS) local oscillator signal tame, so as to obtain high-precision time and frequency standards. Firstly, using MATLAB simulation for GPS tracking signal, through Kalman filtering and application performance analysis, adaptive filtering coefficients obtained crystal tame and dimension x then, in the case of different parameters pi algorithm for the simulation for the existence of a competitive relationship between the various performance indicators to optimize the coefficient of the Proportion Integration (pi) algorithm x finally, combining the Kalma filtering and pi algorithm to filter and adjust phase. The test result shows that, Kalman filtering and pi algorithm combines technology effectively filter out signal noise, the excellent long-term stability characteristics of a standard satellite receiver seconds pulses generated with excellent short-term stability oven controlled crystal characteristics combined, solving local crystal oscillator aging, long term stability in accuracy and poor performance issues, system output frequency accuracy up nanosecond (ns), finally got the short and long term have a high stability, high precision frequency reference and time synchronization standard source.
A simple refinement of Morreale's method yields a useful criterion to identify and cancel the redundant subfunctions generated in the application of the pi-algorithm. Use of such a criterion improves the efficienc...
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A simple refinement of Morreale's method yields a useful criterion to identify and cancel the redundant subfunctions generated in the application of the pi-algorithm. Use of such a criterion improves the efficiency of the algorithm. Extension to multiterminal Boolean functions is also presented.
Pseudo-Derivative-Feedback (PDF) control is compared to pi control through simulation using an approximated dynamic system thermal model of the greenhouse. The effects of time delays on control system performance for ...
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Pseudo-Derivative-Feedback (PDF) control is compared to pi control through simulation using an approximated dynamic system thermal model of the greenhouse. The effects of time delays on control system performance for both PDF and pi control are demonstrated. Results showed PDF control to have a better load handling capability than pi control. PDF control was exceptionally better than pi for systems without time delay and significantly better for systems with time delay. The algorithm was then tested to control a greenhouse section and showed satisfactory results. (C) 2000 Elsevier Science B.V. All rights reserved.
This study presents an improved self-charging algorithm by introducing a new feature known as step size error cancellation for better performance of DC-link capacitor voltage control in single-phase shunt active power...
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This study presents an improved self-charging algorithm by introducing a new feature known as step size error cancellation for better performance of DC-link capacitor voltage control in single-phase shunt active power filter (SAPF). Previous works of self-charging algorithms were focused only for steady-state operation by using either proportional-integral (pi) or fuzzy logic control (FLC). However, in a certain operation of any power system, dynamic operation may also happen. Thus, by introducing step size error cancellation as an additional feature to the self-charging algorithm, both steady state and dynamic operations can be covered. For evaluation and comparison analysis, self-charging with pi and FLC algorithms have been developed too. All the algorithms were simulated in MATLAB-Simulink, respectively, together with the single-phase SAPF. For hardware implementation, the proposed algorithm was programmed in TMS320F28335 digital signal processing board. The other two conventional self-charging algorithms were also programmed for comparison purposes. From the results and analysis, the proposed self-charging with step size error cancellation shows the best performance with high accuracy, fast response time and less overshoot and undershoot. It performs well in both steady state and dynamic operations as compared with both previous self-charging techniques which only work well in steady-state operation.
The performance of Plug-in Hybrid Electric Vehicle (PHEV) depends on the energy management strategy (EMS). An optimal EMS guarantees the maximum use of the energy through electric power grid, coordinates power output ...
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The performance of Plug-in Hybrid Electric Vehicle (PHEV) depends on the energy management strategy (EMS). An optimal EMS guarantees the maximum use of the energy through electric power grid, coordinates power output of main power sources and exerts comprehensive advantages of both engine and motor. However, the current EMS cannot react to the dynamic driving cycles in the future and thus have a bad real-time performance. In order to solve these problems, a novel EMS based on rule-based energy strategy (RE), dynamic programming algorithm (DP) and equivalent fuel consumption algorithm (ECMS) is proposed. First, DP is used to extract the boundary of mode switching and shift schedule under three typical driving cycles in offline, especially, RE is corrected using the boundary of mode switching. Second, an instantaneous optimization strategy-ECMS is used to replace the Charge-Depleting Mode (CD) of RE for finding the real-time optimal solution in a wider range in online, in this part, owe to the fixed distance of urban public transport, a reference State of Charge (SOC) is formulated, and the Proportion-Integration (pi) algorithm is used to make the actual SOC always follow the reference SOC by adjusting the equivalent factor. Finally, combine all the above efforts, a real-time optimization EMS is proposed and validated through simulation and experiment. The results show that this approach can significantly enhance the vehicle drivability, with overall obvious improvement of the comprehensive performance qualification based on both fuel economy and drivability.
In this paper, we propose a novel active fault-tolerant control (AFTC) method for modular manipulators with multiple sensor failure, which is based on adaptive dynamic programming (ADP). Combining the principle of dif...
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ISBN:
(纸本)9781728140940
In this paper, we propose a novel active fault-tolerant control (AFTC) method for modular manipulators with multiple sensor failure, which is based on adaptive dynamic programming (ADP). Combining the principle of diffeomorphism, a first-order filter is introduced to convert sensor faults into pseudo-actuator faults. Combine the sensor faults estimated by the adaptive sensor fault observer to establish the Hamilton-Jacobi-Bellman (HJB) equation. Based on the ADP, the online policy iteration (pi) algorithm is applied to solve the HJB equation by establishing a critic neural network. It is proved that the closed-loop modular manipulators system is asymptotic stability according to the Lyapunov theory. Simulation results of 2-DOF modular manipulator systems with two configurations demonstrate the validity of the proposed algorithm finally.
The paper deals with the best choice for the control sampling period in term of a multicriterial conditioning, with the on-line timing and with a comparison between the conventional (like pi) control algorithms and th...
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ISBN:
(纸本)9789898111326
The paper deals with the best choice for the control sampling period in term of a multicriterial conditioning, with the on-line timing and with a comparison between the conventional (like pi) control algorithms and the fuzzy control. Several useful relations are followed by diagrams obtained in simulation and by different real-time recordings both for the timing and for characteristic variables of the system. Implementations with microcontroller and DSP are used for analyzing the design criterion and the timing strategy. The application field concerns a servodrive, so the real-time constraints are quite strong. The author conceived a general control strategy for the on-line timing based on imbricate interrupts.. each pulse encoder acting on the hardware input interrupt of the control processor.
In this paper, we discuss how to protect satellite signals from strong interference signals The power inversion (pi) algorithm has been widely used in interference suppression. However, both the interference and the s...
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ISBN:
(纸本)9781509048281
In this paper, we discuss how to protect satellite signals from strong interference signals The power inversion (pi) algorithm has been widely used in interference suppression. However, both the interference and the satellite signals are significantly suppressed. Therefore, we further optimized the satellite steering vector and interference steering vector using a multi-star, forming pi approach. To verify the superiority of the new method, we designed an anti-interference hardware platform that includes a seven-element antenna array, a radio frequency (RF) front-end module, a field-programmable gate array (FPGA), and a digital signal processor (DSP)to compare the two algorithms. Using the hardware platform, we compare the traditional pi algorithm to our proposed optimized algorithm using the following three metrics: simulation waveform, direction of arrival (DOA), and positioning. The results show that our method can suppress interference from satellites, resulting in better efficiency than the pi algorithm.
It is worried that the ITS may suffer interference from broadcast system or mobile communication system. Thus, we proposed a power inversion adaptive array which can suppress an interference wave in ITS propagation en...
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ISBN:
(纸本)9781479914722
It is worried that the ITS may suffer interference from broadcast system or mobile communication system. Thus, we proposed a power inversion adaptive array which can suppress an interference wave in ITS propagation environment. However, the interference suppression performance is reduced due to multipath fading. As a countermeasure, we devised a continue control method for power inversion to follow the change of propagation environment. In this paper, the optimal snapshot number for properly estimating a correlation matrix is examined. As the result of examination, it is clarified that the optimal number of snapshots is about 30 times.
The brushless DC motor (BLDCM) is a multi-variable and non-linear system. The mathematical model of the BLDCM is founded, the simulation model of the double closed-loop control system is designed using Matlab6.5, and ...
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ISBN:
(纸本)9780769544151
The brushless DC motor (BLDCM) is a multi-variable and non-linear system. The mathematical model of the BLDCM is founded, the simulation model of the double closed-loop control system is designed using Matlab6.5, and the rotational speed profiles of the electrical machinery are given on the control strategy of traditional pi algorithm and fuzzy-pi algorithm, then the validity of the proposed BLDCM model and the rationality of the control system are all confirmed.
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