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As the sampling rates of the inner loop and the outer loop of the target tracking control system are different, a typical digital multi-rate control system was formed. If the traditional single-rate design method was applied, the low sampling rate loop will seriously impact the dynamical characteristic of the system. After analyzing and calculating the impact law of the low sampling rate loop to the bandwidth and the stability of the tracking system, a kind of multi-rate control system design method was introduced. Corresponding to the different sampling rates of the inner loop and the outer loop, the multi-rate control strategy was constituted by a high sampling rate sub-controller and a low sampling rate sub-controller. The two sub-controllers were designed separately and connected by means of the sampling rate converter. The low sampling rate controller determined the response rapidity of the system, while the high sampling rate controller applied additionally effective control outputs to the system during a sampling interval of the low sampling rate controller. With the introduced high and low sampling rates sub-controllers, the tracking control system can achieve the same performance as a single-rate controller with high sampling rate, yet it works under a much lower sampling rate. The simulation and experimental results show the effectiveness of the introduced multi-rate control design method. It reduces the settling time by 5 times and the over shoot by 4 times compared with the PID control. 相似文献
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为寻找一种可用于连续化生产低聚甘油的固体碱催化剂,采用共沉淀法将Na+、K+、Ca2+、Sr2+、Ba2+掺杂到ZrO2中,分别制得Na/ZrO2、K/ZrO2、Ca/ZrO2、Sr/ZrO2、Ba/ZrO2,同时将制得的催化剂用于合成低聚甘油。通过XRD、Raman、CO2-TPD等方法研究掺杂不同金属离子对催化剂结构及其表面碱度的影响。采用GC,ICP等方法研究催化剂的活性和稳定性。结果表明,Na/ZrO2,K/ZrO2为单斜相,Ba/ZrO2为四方相,Ca/ZrO2,Sr/ZrO2为立方相,且各催化剂表现出不同的碱性位点。五种催化剂中Ca/ZrO2表现出最佳的稳定性, Ca2+浸出量为0.003%,催化剂用量减半并循环4次后,甘油转化率保持在22%以上,催化剂回收率在95%以上。在Ca/ZrO2用量为1 g,甘油用量100 g,反应温度270 ℃,反应24 h的条件下,低聚甘油产率为73.05%,选择性为100%。 相似文献
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根据云台系统对传感器采集量实时性和快速性要求,在传统云台单处理器控制电路的基础上,设计了以DSP芯片TMS320F28335为伺服控制核心及FPGA芯片EP4CE10E22C8为外设管理核心的一种新型云台伺服控制电路,给出了该控制电路重要部分的芯片选型及电路设计原理,并采用模块化编程完成相应软件设计。实验中通过分析绝对式编码器信号采集等关键模块的时序信息,准确计算数据刷新频率和并行通信周期,证明该设计可以有效提高处理器获取云台位置及姿态信息的时效性,验证了控制电路的科学性和合理性,同时具有高集成度、功能可拓展等优点。 相似文献
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基于虚拟样机的磁悬浮控制系统仿真 总被引:3,自引:0,他引:3
自从磁浮列车的概念诞生起,研究者们一直采用微分方程描述方法对系统进行研究。但是由于系统是多点耦合,并且严重非线性,这种传统的研究方法已经不能满足研究需要,磁浮列车的飞速发展迫切需要一种新的有效的研究手段。虚拟样机技术是近几年在国际上逐渐发展起来的,它利用三维实物图形建立模型,避免了描述微分方程的困难。文中利用AD—AMS虚拟样机软件组建详细的磁浮列车单个转向架三维模型,以垂向控制系统为研究对象进行虚拟样机仿真分析。最后给出了车辆慢慢悬浮和激励测试的仿真结果,这一结果与实验现象是一致的。该文将虚拟样机技术与磁浮列车系统技术研究有效地结合起来。 相似文献
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