A calibrating device for the Rogowski coil is developed, which can be used to calibrate the Rogowski coil having a partial response time within tens of nanoseconds. Its key component is a step current generator, which...A calibrating device for the Rogowski coil is developed, which can be used to calibrate the Rogowski coil having a partial response time within tens of nanoseconds. Its key component is a step current generator, which can generate the output with a rise time of less than 2 ns and a duration of larger than 300 ns. The step current generator is composed by a pulse forming line （PFL） and a pulse transmission line （PTL）. A TEM （transverse electromagnetic mode） coaxial measurement unit is used as PTL, and the coil to be calibrated and the referenced standard Rogowski coil can be fixed in the unit. The effect of the dimensions of the TEM unit is discussed theoretically as well as experimentally.展开更多
The Bayesian approach is considered as the most general formulation of the state estimation for dynamic systems. However, most of the existing Bayesian estimators of stochastic hybrid systems only focus on the Markov ...The Bayesian approach is considered as the most general formulation of the state estimation for dynamic systems. However, most of the existing Bayesian estimators of stochastic hybrid systems only focus on the Markov jump system, few liter- ature is related to the estimation problem of nonlinear stochastic hybrid systems with state dependent transitions. According to this problem, a new methodology which relaxes quite a restrictive as- sumption that the mode transition process must satisfy Markov properties is proposed. In this method, a general approach is presented to model the state dependent transitions, the state and output spaces are discreted into cell space which handles the nonlinearities and computationally intensive problem offline. Then maximum a posterior estimation is obtained by using the Bayesian theory. The efficacy of the estimator is illustrated by a simulated example .展开更多
文摘A calibrating device for the Rogowski coil is developed, which can be used to calibrate the Rogowski coil having a partial response time within tens of nanoseconds. Its key component is a step current generator, which can generate the output with a rise time of less than 2 ns and a duration of larger than 300 ns. The step current generator is composed by a pulse forming line （PFL） and a pulse transmission line （PTL）. A TEM （transverse electromagnetic mode） coaxial measurement unit is used as PTL, and the coil to be calibrated and the referenced standard Rogowski coil can be fixed in the unit. The effect of the dimensions of the TEM unit is discussed theoretically as well as experimentally.
基金supported by the National Natural Science Foundation of China (6097400161104121)the Fundamental Research Funds for the Central Universities (JUDCF11039)
文摘The Bayesian approach is considered as the most general formulation of the state estimation for dynamic systems. However, most of the existing Bayesian estimators of stochastic hybrid systems only focus on the Markov jump system, few liter- ature is related to the estimation problem of nonlinear stochastic hybrid systems with state dependent transitions. According to this problem, a new methodology which relaxes quite a restrictive as- sumption that the mode transition process must satisfy Markov properties is proposed. In this method, a general approach is presented to model the state dependent transitions, the state and output spaces are discreted into cell space which handles the nonlinearities and computationally intensive problem offline. Then maximum a posterior estimation is obtained by using the Bayesian theory. The efficacy of the estimator is illustrated by a simulated example .
