共查询到20条相似文献,搜索用时 62 毫秒
1.
详细介绍了半导体制冷器的失效机理、可靠性和寿命。引用的大量数据证明半导体制冷器是一种高可靠性的温差电器件。从而为深入研究半导体制冷器的可靠性和寿命提供了可靠的理论依据和实验参考。 相似文献
2.
3.
针对传统继电反馈模型辨识精度较低的问题,介绍了一种新型的移位继电反馈方法,并根据辨识结果设计了基于模型的预测PI控制器。移位继电法采用带滞环的偏置继电器,能够从单次继电反馈测试实验得到模型的三个频率响应点,移位继电法不需要任何模型先验知识,并且辨识精度较高。预测PI控制对于时滞环节具有良好的控制性能,根据移位法与ATV法的辨识结果分别设计了预测PI控制器进行仿真比较,仿真结果验证了移位继电法的实用性。 相似文献
4.
5.
本文用控制论与生物物理学的方法对人体体温国庆节和外部控制的方式进行了研究和探讨,在建模的过程中充分利用了现代计算机的功能,大胆仿真人体本身的调节机制来建立一个接近可用的系统。 相似文献
6.
7.
大多数实际物理系统的模型本质上是连续的,连续时间模型为物理系统的行为提供了更好的解释。提出了一种采样数据中存在高频有色噪声的连续模型辨识方法,该方法通过引入积分运算,将连续时间系统的微分方程模型转换为积分方程模型,从而使噪声的影响可以忽略,然后直接利用传统的最小二乘法估计出系统的连续时间模型参数。该方法具有较强的抗有色噪声干扰的鲁棒性、计算方法简单、参数辨识精度高等优点。仿真实例验证了该方法的有效性和可行性。 相似文献
8.
锂电池参数辨识模型的设计与研究 总被引:2,自引:2,他引:0
电动汽车动力电池内部参数随负载与工况而发生变化,因此建立准确的动力电池模型尤为必要。基于锂电池等效电路模型并着重考量运行温度与荷电状态对各元件参数的影响,依托充放电法、复合脉冲特性充放电试验并结合最小二乘法实现模型中各元件参数辨识。通过Simulink平台构建动力电池模型与充放电模型,上述模型通过安时计量法同时考虑温度影响实现荷电状态的准确估算。结果表明,该锂电池参数辨识模型可准确模拟各种负载工况下动力电池的运行特性,该设计可应用于动力电池的测试与开发。 相似文献
9.
介绍了模型辨识器的设计和实际应用.模型辨识器的辨识算法采用基于模型分解方法的辨识算法,软件设计上采用模块化的程序设计原则.辨识器从实用性出发,注重辨识的速度、简洁,可以方便给出系统对象的阶次、参数和时延的无偏估计,可以灵活地对多变量系统进行辨识,辨识出的模型有利于控制器的设计.还对一个实际的装置进行了应用研究,获得的结果是精确的,说明了该软件的有效性和实用性. 相似文献
10.
11.
设计了一种高精度、外围元件较少的热电致冷温度控制电路。介绍了激光器温度控制电路的系统组成及工作原理,重点论述了采用基于TPS63000的热电致冷控制电路,通过MCU的数字PID控制算法对EML激光器温度进行精确调节的过程。实验结果表明,该电路完全符合EML激光器对温度稳定性的要求。 相似文献
12.
13.
14.
15.
In the recent past, mobile robots with high mobility have been developed actively. We have already proposed a holonomic and omnidirectional mobile robot using two active dual-wheel caster assemblies and also derived the kinematic models for the assembly and the mobile robot. This paper presents dynamic analysis and control for the mobile robot. The dynamic model has been derived based on the forces acting on the steering axis. Then a model-based resolved acceleration controller is constructed. The validity of the model and the effectiveness of the control system are confirmed by experiments using a prototype robot as well as simulations. 相似文献
16.
In this paper, we exploit an adaptive control scheme to adjust highly sensitive oscillations of fluid conveying carbon nanotube (CNT) resonators. Firstly, we focus on the nonlinear vibrations of the fluid conveying CNTs, considering an added mass using nonlocal Euler‐Bernoulli beam theory. CNT rests on nonlinear Winkler and Pasternak foundations. We use the Galerkin method to extract the nonlinear ordinary differential equation models of the CNT oscillations. We elicit a linear parametric model for estimating the added mass and other parameters of the system. Numerical simulations delineate that the developed model has sensitivity to added mass at the yoctogram level. It is known that CNT vibrations are very sensitive to small perturbations. Accordingly, a small perturbation results in significantly abrupt changes in the vibrational parameters of the targeted system. For that reason, it is crucial to have a potent apparatus for identifying the system parameters in case of sudden changes in the vibrational parameters. For such parameter identification, a least squares (LS) parameter identification algorithm and an extended Luenberger observer are integrated to a pole placement controller for online estimation of the system parameters as well as vibration control of the objective system. It is well‐known that CNTs are potentially ideal atomic force microscopy (AFM) probes, and accordingly, the proposed method is potentially beneficial for identifying highly sensitive motions in AFM. In addition, numerical simulations are presented, showing that the proposed adaptive controller has the potential to be used for vibration control of the CNT resonators even in the case of chaotic motions. 相似文献
18.
针对基于角色的访问控制(RBAC)模型在业务处理流程中访问控制粒度过粗和无法动态调整授权等方面的问题,提出了一种面向业务的动态RBAC模型(BO-RBAC)。该模型参考基于任务的访问控制(TBAC)模型,引入了业务、业务步和授权步等概念,并形式化定义了模型的基本集合;同时将授权过程分为角色授权和授权步授权两部分,将业务执行视为随机过程,给出了基于马尔可夫链的动态授权方法;最后使用C++14对模型进行了实现。BO-RBAC模型结合了RBAC与TBAC的特点,具有访问控制粒度细、授权动态调整、满足安全规范等优点。 相似文献
19.
20.
A problem of developing an identification algorithm for a linear discrete dynamic control system is considered. The solution is based on the derived formulas for the differentiation of quadratic functionals with respect to matrix variables. An example is given. 相似文献