行星齿轮箱广泛应用于低速重载的大型机电设备中,其故障检测尤为重要。当前行星齿轮箱的故障检测主要依靠振动信号分析,然而低转速工况导致的冲击微弱以及故障冲击难以分离等问题,使得行星齿轮箱故障冲击难以发掘。针对上述瓶颈,提出一...行星齿轮箱广泛应用于低速重载的大型机电设备中,其故障检测尤为重要。当前行星齿轮箱的故障检测主要依靠振动信号分析,然而低转速工况导致的冲击微弱以及故障冲击难以分离等问题,使得行星齿轮箱故障冲击难以发掘。针对上述瓶颈,提出一种基于编码器信号的低转速行星齿轮箱故障诊断方法。该方法首先通过内置编码器获取故障信息,避免了冗长的振动传递路径带来的不利影响。在此基础上,建立稀疏低秩分解模型,引入快速主成分追踪算法(fast principal component pursuit,FPCP)进行求解,实现低转速下行星齿轮箱故障冲击的提取。行星齿轮箱故障实验结果表明,该方法不仅能获取输入轴转速为30r/min下的故障信息,而且有效地实现故障冲击的分离。研究工作可为低转速旋转机械的故障诊断提供有效的工具。展开更多
In the electricity market, charging based on the traditional spot electricity price often results in the payment imbalance of electric network, and goes against the development of the power system. So, it is necessary...In the electricity market, charging based on the traditional spot electricity price often results in the payment imbalance of electric network, and goes against the development of the power system. So, it is necessary to modify the spot price. The key of the modification lies in how to calculate the fixed unit transmission cost of each node, that is how to allocate the fixed transmission cost to users.To solve this problem, we develop a power flow tracing algrithm to modify the spot price. We put forward a path searching method based on the graph theory after studying the fundamental principle of power flow tracing and apply the method to the downstream tracing algorithm and upstream tracing algorithm according to the proportional distribution principle. Furthermore, to improve the computational efficiency of the algorithm, we introduce the branch expunction method to optimize the node order. By using the result of power flow tracing to get fixed node transmission cost and introducing it to modify the spot price, we obtain the synthetical price.The application to a 5-bus system prove the algorithm feasible.展开更多
文摘行星齿轮箱广泛应用于低速重载的大型机电设备中,其故障检测尤为重要。当前行星齿轮箱的故障检测主要依靠振动信号分析,然而低转速工况导致的冲击微弱以及故障冲击难以分离等问题,使得行星齿轮箱故障冲击难以发掘。针对上述瓶颈,提出一种基于编码器信号的低转速行星齿轮箱故障诊断方法。该方法首先通过内置编码器获取故障信息,避免了冗长的振动传递路径带来的不利影响。在此基础上,建立稀疏低秩分解模型,引入快速主成分追踪算法(fast principal component pursuit,FPCP)进行求解,实现低转速下行星齿轮箱故障冲击的提取。行星齿轮箱故障实验结果表明,该方法不仅能获取输入轴转速为30r/min下的故障信息,而且有效地实现故障冲击的分离。研究工作可为低转速旋转机械的故障诊断提供有效的工具。
文摘In the electricity market, charging based on the traditional spot electricity price often results in the payment imbalance of electric network, and goes against the development of the power system. So, it is necessary to modify the spot price. The key of the modification lies in how to calculate the fixed unit transmission cost of each node, that is how to allocate the fixed transmission cost to users.To solve this problem, we develop a power flow tracing algrithm to modify the spot price. We put forward a path searching method based on the graph theory after studying the fundamental principle of power flow tracing and apply the method to the downstream tracing algorithm and upstream tracing algorithm according to the proportional distribution principle. Furthermore, to improve the computational efficiency of the algorithm, we introduce the branch expunction method to optimize the node order. By using the result of power flow tracing to get fixed node transmission cost and introducing it to modify the spot price, we obtain the synthetical price.The application to a 5-bus system prove the algorithm feasible.
