Transfer function

About: Transfer function is a research topic. Over the lifetime, 14362 publications have been published within this topic receiving 214983 citations. The topic is also known as: system function & network function.

A Transfer Function Approach for a Generalized Electrochemical Impedance Spectroscopy

Abstract: The electrochemical interface is treated here as a multi-input/multi-output system. This approach allows application of new measurement techniques based on the sinusoidal perturbation or the sinusoidal response of nonelectrical quantities in addition to the usual electrochemical parameters (i.e., potential or current). Used in conjunction with the usual electrochemical impedance, these new transfer functions allow extra information to be obtained on the interface. Some examples are given corresponding to input perturbation related to light, magnetic field, temperature, and angular velocity of the electrode and output responses related to mass, optical reflection, and the currents in a ring-disk system

Digital implementation of a line current shaping algorithm for three phase high power factor boost rectifier without input voltage sensing

Abstract: In this paper the implementation of a simple yet high performance digital current mode controller that achieves high power factor operation for three phase boost rectifier is described. The indicated objective is achieved without input voltage sensing and without transformation of the control variables into rotating reference frame. The controller uses the concept of resistance emulation for shaping of input current like input voltage in digital implementation. Two decoupled fixed frequency current mode controllers calculate the switching instants for equivalent single phase boost rectifiers. A combined switching strategy is developed in the form of space vectors to simultaneously satisfy the timing requirements of both the current mode controllers in a switching period. Conventional phase locked loop (PLL) is not required as converter switching is self-synchronized with the input voltage. Analytical formula is derived to obtain the steady state stability condition of the converter. A linear, low frequency, small signal model of the three phase boost rectifier is developed and verified by measurement of the voltage control transfer function. In implementation Texas Instruments's DSP TMS320F240F is used as the digital controller. The algorithm is tested on a 10-kW, 700-V dc, three phase boost rectifier.

Method and apparatus for simulating aural response information

Abstract: Speech and like signals are analyzed based on a model of the function of the human hearing system. The model of the inner ear is expressed as signal processing operations which map acoustic signals into neural representations. Specifically, a high order transfer function is modeled as a cascade/parallel filterbank network of simple linear, time-invariant second-order filter sections. Signal transduction and compression are based on a half-wave rectification with a non-linearly coupled, variable time constant automatic gain control network. The result is a simple device which simulates the complex signal transfer function associated with the human ear. The invention lends itself to implementation in digital circuitry for real-time or near real-time processing of speech and other sounds.

An efficient method to compute transfer function of a transformer from its equivalent circuit

Abstract: The dynamics of an electrical network can completely be described from the knowledge of its poles and zeros. Computation of poles and zeros of the transfer function (TF) of a transformer winding, represented as a coupled ladder network, involves solution of a large-sized equivalent circuit. This paper presents a novel solution based on state space analysis approach. It is shown, how the linearly transformed state space formulation, together with algebraic manipulations, can become useful. In the proposed formulation, symbolic variables (i.e., Laplace variable, s) are suitably manipulated, so as to render computations purely numerical. With this feature, there is practically no limit on the size of networks and topologies (including resistances to model losses) that can be represented. So, virtually any number of windings of a transformer can be considered, permitting a comprehensive analysis of winding behavior and its interactions, that was until now severely limited, by the simplifying assumptions imposed by existing methods.