An open-plus-closed-loop （OPCL） control problem for the chaotic motion of a 3D rigid pendulum subjected to a constant gravitationM force is studied. The 3D rigid pendulum is assumed to be consist of a rigid body sup...An open-plus-closed-loop （OPCL） control problem for the chaotic motion of a 3D rigid pendulum subjected to a constant gravitationM force is studied. The 3D rigid pendulum is assumed to be consist of a rigid body supported by a fixed and frictionless pivot with three rotational degrees. In order to avoid the singular phenomenon of Euler＇s angular velocity equation, the quaternion kinematic equation is used to describe the motion of the 3D rigid pendulum. An OPCL controller for chaotic motion of a 3D rigid pendulum at equilibrium position is designed. This OPCL controller contains two parts： the open-loop part to construct an ideal trajectory and the closed-loop part to stabilize the 3D rigid pendulum. Simulation results show that the controller is effective and efficient.展开更多
An analysis technique of steady state and stability for closed-loop PWM DC/DC switching converters is presented. Using this method, the closed-loop switching converter is transformed into an open-loop system. By means...An analysis technique of steady state and stability for closed-loop PWM DC/DC switching converters is presented. Using this method, the closed-loop switching converter is transformed into an open-loop system. By means of the fact that in steady state, the two boundary values are equal in one switching period. The exponential matrix is evaluated by precise time-domain-integration method, and then the related curve between feedback duty cycle and the input one is obtained. Not only can the steady-state duty cycle be found from the curve, but also the stability and stable domain of the system. Compared with other methods, it features with simplicity and less calculation, and fit for numerical simulation and analysis for closed-loop switching converters. The simulation results of examples indicate the correctness of the presented method.展开更多
This paper explores the model reference adaptive control problem for a class of switched linear systems under arbitrary switching with no need for the measurability of the system state.Based on the state of reference ...This paper explores the model reference adaptive control problem for a class of switched linear systems under arbitrary switching with no need for the measurability of the system state.Based on the state of reference model and the measurable output error, adaptive laws and controllers are designed for switched systems.Each subsystem may have its individual reference model and controller, which increases the design flexibility.The introduction of the closed-loop reference model is to get a better transient performance of the whole switched systems.A numerical example is provided to verify the effectiveness of the main results.展开更多
To achieve a high precision capacitive closed-loop micro-accelerometer,a full differential CMOS based on switched-capacitor circuit was presented in this paper as the sensor interface circuit.This circuit consists of ...To achieve a high precision capacitive closed-loop micro-accelerometer,a full differential CMOS based on switched-capacitor circuit was presented in this paper as the sensor interface circuit.This circuit consists of a balance-bridge module,a charge sensitive amplifier,a correlated-double-sampling module,and a logic timing control module.A special two-path feedback circuit configuration was given to improve the system linearity.The quantitative analysis of error voltage and noise shows that there is tradeoff around circuit's noise,speed and accuracy.A detailed design method was given for this tradeoff.The noise performance optimized circuit has a noise root spectral density of 1.0 μV/Hz,equivalent to rms noise root spectral density of 1.63 μg/Hz.Therefore,the sensor's Brown noise becomes the main noise source in this design.This circuit is designed with 0.5 μm n-well CMOS process.Under a ±5 V supply,the Hspice simulation shows that the system sensitivity achieves 0.616 V/g,the system offset is as low as 1.456 mV,the non-linearity is below 0.03%,and the system linear range achieves ±5 g.展开更多
随着光伏和风能等可再生能源在柔性配电网中的比例不断提高,可再生能源发电的间歇性输出给电力系统带来了不稳定性与波动性。现有的柔性合环开关因为硬件参数和容量限制,无法应对负荷超容量波动带来的频率超限及潮流转移造成的电网开路...随着光伏和风能等可再生能源在柔性配电网中的比例不断提高,可再生能源发电的间歇性输出给电力系统带来了不稳定性与波动性。现有的柔性合环开关因为硬件参数和容量限制,无法应对负荷超容量波动带来的频率超限及潮流转移造成的电网开路问题。因此,有必要将柔性合环开关与储能技术相结合,构建新型柔性互联配电网,对带电池储能系统的多端口柔性合环开关设计相应的控制策略。首先,对于硬件参数不同和工作状态差异造成的储能单元荷电状态(state of charge,SOC)不均衡,设计自适应的SOC均衡控制策略。其次,对负荷大波动和稳压侧开路故障,设计切换策略以调节电网频率并进行短时直流电压支撑,确保下级负荷的稳定运行。最后,利用基于MATLAB/Simulink平台的仿真模型和RTLAB硬件在环平台验证了所提协调控制策略的有效性和实用性。展开更多
基金supported by the National Natural Science Foundation of China(No.11072038)the Municipal Key Programs of Natural Science Foundation of Beijing(No.KZ201110772039)
文摘An open-plus-closed-loop （OPCL） control problem for the chaotic motion of a 3D rigid pendulum subjected to a constant gravitationM force is studied. The 3D rigid pendulum is assumed to be consist of a rigid body supported by a fixed and frictionless pivot with three rotational degrees. In order to avoid the singular phenomenon of Euler＇s angular velocity equation, the quaternion kinematic equation is used to describe the motion of the 3D rigid pendulum. An OPCL controller for chaotic motion of a 3D rigid pendulum at equilibrium position is designed. This OPCL controller contains two parts： the open-loop part to construct an ideal trajectory and the closed-loop part to stabilize the 3D rigid pendulum. Simulation results show that the controller is effective and efficient.
文摘An analysis technique of steady state and stability for closed-loop PWM DC/DC switching converters is presented. Using this method, the closed-loop switching converter is transformed into an open-loop system. By means of the fact that in steady state, the two boundary values are equal in one switching period. The exponential matrix is evaluated by precise time-domain-integration method, and then the related curve between feedback duty cycle and the input one is obtained. Not only can the steady-state duty cycle be found from the curve, but also the stability and stable domain of the system. Compared with other methods, it features with simplicity and less calculation, and fit for numerical simulation and analysis for closed-loop switching converters. The simulation results of examples indicate the correctness of the presented method.
基金Sponsored by the National Natural Science Foundation of China(Grant No.61233002)the 111 Project(Grant No.B16009)the IAPI Fundamental Research Funds(Grant No.2013ZCX03-01)
文摘This paper explores the model reference adaptive control problem for a class of switched linear systems under arbitrary switching with no need for the measurability of the system state.Based on the state of reference model and the measurable output error, adaptive laws and controllers are designed for switched systems.Each subsystem may have its individual reference model and controller, which increases the design flexibility.The introduction of the closed-loop reference model is to get a better transient performance of the whole switched systems.A numerical example is provided to verify the effectiveness of the main results.
基金Sponsored by the National High Technology Research and Development Program of China(863Program)(Grant No.2008AA042201)
文摘To achieve a high precision capacitive closed-loop micro-accelerometer,a full differential CMOS based on switched-capacitor circuit was presented in this paper as the sensor interface circuit.This circuit consists of a balance-bridge module,a charge sensitive amplifier,a correlated-double-sampling module,and a logic timing control module.A special two-path feedback circuit configuration was given to improve the system linearity.The quantitative analysis of error voltage and noise shows that there is tradeoff around circuit's noise,speed and accuracy.A detailed design method was given for this tradeoff.The noise performance optimized circuit has a noise root spectral density of 1.0 μV/Hz,equivalent to rms noise root spectral density of 1.63 μg/Hz.Therefore,the sensor's Brown noise becomes the main noise source in this design.This circuit is designed with 0.5 μm n-well CMOS process.Under a ±5 V supply,the Hspice simulation shows that the system sensitivity achieves 0.616 V/g,the system offset is as low as 1.456 mV,the non-linearity is below 0.03%,and the system linear range achieves ±5 g.
文摘随着光伏和风能等可再生能源在柔性配电网中的比例不断提高,可再生能源发电的间歇性输出给电力系统带来了不稳定性与波动性。现有的柔性合环开关因为硬件参数和容量限制,无法应对负荷超容量波动带来的频率超限及潮流转移造成的电网开路问题。因此,有必要将柔性合环开关与储能技术相结合,构建新型柔性互联配电网,对带电池储能系统的多端口柔性合环开关设计相应的控制策略。首先,对于硬件参数不同和工作状态差异造成的储能单元荷电状态(state of charge,SOC)不均衡,设计自适应的SOC均衡控制策略。其次,对负荷大波动和稳压侧开路故障,设计切换策略以调节电网频率并进行短时直流电压支撑,确保下级负荷的稳定运行。最后,利用基于MATLAB/Simulink平台的仿真模型和RTLAB硬件在环平台验证了所提协调控制策略的有效性和实用性。
