Modeling of supercapacitor modules in the hybrid powertrain with a nonlinear 3-branch equivalent circuit

Abstract

Summary In this study, a nonlinear 3‐branch equivalent circuit model is established that considers the instantaneous dynamic characteristics of supercapacitors. A dynamic capacitor Cf is introduced to represent the effect that the terminal voltage has on the capacitance for supercapacitors based on the traditional model, which can improve the precision of the description of a supercapacitor's dynamic characteristics. Then, the parameters of the supercapacitor model are identified using Levenberg‐Marqurdt method, and a simulation analysis and experimental validation are performed. The simulation and experiment results show that the linear and nonlinear 3‐branch equivalent model can quickly track the measured voltage value under the dynamic working conditions of Economic Commission for Europe and Urban Dynamometer Driving Schedule. However, the nonlinear 3‐branch equivalent circuit model has a smaller voltage error, and the minimum error is 2.16%. In summary, the proposed nonlinear equivalent circuit model can more accurately reflect the actual dynamic characteristics of supercapacitors with a better engineering application value.

A comparative study and parameterization of supercapacitor electrical models applied to hybrid electric vehicles

“…En este caso, el modelo de Thevenin con histéresis es el que mejor precisión muestra. Adicionalmente en [57], se realiza la comparativa de redes RC en serie pero con valores constantes, los cuales son incapaces de representar las no linealidades presentes en el supercondensador [58]. En la estimación de los parámetros se utiliza algoritmos genéticos, inteligencia artificial, entre otros, [56] y [59].…”

“…En [108] se analiza la equivalencia de los tres modelos RC de parámetros constantes, pudiendo utilizar un equivalente u otro, en función de la aplicación. Sin embargo, como se muestra en [58], la precisión del modelo puede mejorarse con un modelo eléctrico de circuito equivalente no lineal. Así, en [109] los autores comparan tres modelos de circuitos equivalentes (Miller, Zubieta y Thevenin), con un perfil de corriente de identificación específico para cada modelo.…”

State of charge estimation of ultracapacitor based on forgetting factor recursive least square and extended Kalman filter algorithm at full temperature range

“…The indirect SOC estimation of ultracapacitor depends on the accurate characterization parameter identification results [22] . Xie et al [23] used the Levenberg-Marqurdt method to identify model parameters. The simulation error of the nonlinear 3-branch ECM was smaller.…”

Experimental design for an enhanced parametric modeling of supercapacitor equivalent circuit model

“…Control systems of supercapacitor or operational boundaries and cutoff points can be acquired from a model, amplifying the lifetime of the capacity and hence accomplishing a more significant level of unwavering quality and competitiveness [20]. Numerous SC models have been distributed in the literature for various purposes, including describing electrical unique behavior, which is of most extreme significance for the industrial applications [21].…”