Prospects of regenerative current breaking in DC circuit breaker topology

Due to the stunning advancement of power electronics, DC power system is getting immense attention in the field of research. Protection and hereafter the protective devices for the DC power system application are two vital areas that need to be explored and developed further. Designing a protective device such as DC circuit breaker possesses a lot of challenges. The main challenge is to interrupt a current which does not have a natural zero crossing like AC current has. In addition, energy is stored in the network inductances during normal operation. Instantaneous current breaking is opposed by this stored energy during circuit breaker tripping, hence, all the DC circuit breaker topologies proposed in literature use snubber network, nonlinear resistor to dissipate this stored energy as heat during the current breaking operation. However, it is possible to store this energy momentarily and reuse it later by developing an improvised topology. In this paper, the prospects of energy recovery and reuse in a DC circuit breaker was studied and a new topology with regenerative current breaking capability had been proposed. This new topology can feed the stored energy of the network back into the same network after breaking the current and thus can improve the overall system efficiency.

Application of particle swarm optimization with ANFIS model for double scroll chaotic system

The predictions for the original chaos patterns can be used to correct the distorted chaos pattern which has changed due to any changes whether from undesired disturbance or additional information which can hide under chaos pattern. This information can be recovered when the original chaos pattern is predicted. But unpredictability is most features of chaos, and time series prediction can be used based on the collection of past observations of a variable and analysis it to obtain the underlying relationships and then extrapolate future time series. The additional information often prunes away by several techniques. This paper shows how the chaotic time series prediction is difficult and distort even if Neuro-Fuzzy such as Adaptive Neural Fuzzy Inference System (ANFIS) is used under any disturbance. The paper combined particle swarm (PSO) and (ANFIS) to exam the prediction model and predict the original chaos patterns which comes from the double scroll circuit. Changes in the bias of the nonlinear resistor were used as a disturbance. The predicted chaotic data is compared with data from the chaotic circuit.

A physical memristor based Muthuswamy–Chua–Ginoux system

In 1976, Leon Chua showed that a thermistor can be modeled as a memristive device. Starting from this statement we designed a circuit that has four circuit elements: a linear passive inductor, a linear passive capacitor, a nonlinear resistor and a thermistor, that is, a nonlinear “locally active” memristor. Thus, the purpose of this work was to use a physical memristor, the thermistor, in a Muthuswamy–Chua chaotic system (circuit) instead of memristor emulators. Such circuit has been modeled by a new three-dimensional autonomous dynamical system exhibiting very particular properties such as the transition from torus breakdown to chaos. Then, mathematical analysis and detailed numerical investigations have enabled to establish that such a transition corresponds to the so-called route to Shilnikov spiral chaos but gives rise to a “double spiral attractor”.

Three-Saddle-Foci Chaotic Behavior of a Modified Jerk Circuit with Chua’s Diode

This paper investigates the chaotic behavior of a modified jerk circuit with Chua’s diode. The Chua’s diode considered here is a nonlinear resistor having a symmetric piecewise linear voltage-current characteristic. To describe the system, we apply fundamental laws in electrical circuit theory to formulate a mathematical model in terms of a third-order (jerk) nonlinear differential equation, or equivalently, a system of three first-order differential equations. The analysis shows that this system has three collinear equilibrium points. The time waveform and the trajectories about each equilibrium point depend on its associated eigenvalues. We prove that all three equilibrium points are of type saddle focus, meaning that the trajectory of (x(t),y(t)) diverges in a spiral form but z(t) converges to the equilibrium point for any initial point (x(0),y(0),z(0)). Numerical simulation illustrates that the oscillations are dense, have no period, are highly sensitive to initial conditions, and have a chaotic hidden attractor.

Relaxation Oscillations in a Nonsmooth Oscillator with Slow-Varying External Excitation

The main purpose of the paper is to explore the influence of the coupling of two scales on the dynamics of a nonsmooth dynamical system. Based on a typical Chua’s circuit, by introducing a nonlinear resistor with piecewise characteristics as well as a harmonically changed electric source, a modified nonsmooth model is established, in which the coupling of two scales in frequency domain exists. Different types of bursting oscillations, appearing in the combination of large-amplitude oscillations, called spiking oscillations ([Formula: see text]), and small-amplitude oscillations or at rest, denoted by quiescent states ([Formula: see text]), can be observed with the variation of the exciting amplitude. When the exciting frequency is relatively small, by regarding the whole exciting term as a slow-varying parameter, the original system can be transformed into a generalized autonomous system. The phase space can be divided into three regions by the nonsmooth boundaries, in which the trajectory is governed by three different subsystems, respectively. Based on the analysis of the three subsystems as well as the behaviors on the nonsmooth boundaries, all the equilibrium branches and their bifurcations can be obtained, which can be employed to investigate the mechanism of the bursting oscillations. It is found that, for relatively small exciting amplitude, since no bifurcation on the equilibrium branches can be realized with the variation of the slow-varying parameter, the system behaves in periodic movement, which may evolve to bursting oscillations when a pair of fold bifurcations occurs with the increase of the exciting amplitude. Further increase of the exciting amplitude may lead to more complicated bursting oscillations, which may bifurcate into two coexisted asymmetric bursting attractors via symmetric breaking. Interaction between the two attractors may result in an enlarged symmetric bursting attractor, in which more forms of bifurcations at the transitions between the quiescent states and repetitive spiking states can be observed.

A Transformation Methodology of Normal Nonlinear Resistors/Conductors to Inverses

This work proposes a simple transformation methodology of normal nonlinear resistors/conductors to their inverted topologies in their floating and grounded versions (NNR/C). It is demonstrated that inverted topologies can also be configured as incremental or decremental nonlinear resistors/conductors. The main fingerprints of an NNR/C are holding up after the transformation and it is demonstrated that an inverse nonlinear resistor/conductor becomes a linear resistor/conductor when the operating frequency of the signal source decreases, inverse behavior in comparison with one memristor. Illustrative examples are given for floating and grounded nonlinear resistors and in both configurations. HSPICE simulation results are provided confirming the theory. Moreover, the normal and inverses resistors can be reconfigured in order to be used in future applications such as programmable analog circuits.

Operating conditions analysis of memristor model

The two terminal, fourth basic circuit element, memristor acts as nonlinear resistor with built-in memory functionality. Memristor has many advantages like non-volatile, no leakage current, Even when the power supply turn off, it retains its memory and typically apparent only at small scale. It shows significant effect in digital circuit application because it stores logic values without power consumption and logic values are measured based on the memristance value. Memristor is a class of non-volatile memory storage and is suitable for nanoscale memory applications. It is considered one of the most promising technology to implement memory and logic operations in a single cell. In this technology stored information is calculated as a low resistive state (LRS) and high resistive state (HRS). A detailed operating conditions of tunneling modulation model of memristor is studied and analyzed the operating frequency and voltage ranges in this paper. Switching behavior is measured based on the transition time of memristance change from one state to another state at different working frequencies.

Does a Standalone, “Cold” (Low-Thermal-Noise), Linear Resistor Exist Without Cooling?

Classical ways of cooling require some of these elements: phase transition, compressor, nonlinearity, valve and/or switch. A recent example is the 2018 patent of Linear Technology Corporation; they utilize the shot noise of a diode to produce a standalone nonlinear resistor that has [Formula: see text]/2 noise temperature (about 150[Formula: see text]K). While such “resistor” can cool its environment when it is AC coupled to a resistor, the thermal cooling effect is only academically interesting. The importance of the invention is of another nature: In low-noise electronics, it is essential to have resistors with low-noise temperature to improve the signal-to-noise ratio. A natural question is raised: can we use a linear system with feedback to cool and, most importantly, to show reduced noise temperature? Exploring this problem, we were able to produce standalone linear resistors showing strongly reduced thermal noise. Our must successful test shows [Formula: see text]/100 (about 3[Formula: see text]K) noise temperature, as if the resistor would have been immersed in liquid helium. We also found that there is an old solution offering similar results utilizing the virtual ground of an inverting amplifier at negative feedback. There, the “cold” resistor is generated at the input of an amplifier. On the other hand, our system generates the “cold” resistance at the output, which can have practical advantages.

SPICE Simulation of Memristor Series and Parallel

Memory Resistors also known as Memristors, is a nonlinear resistor with memory. It is the fourth basic circuit element except resistor, capacitor and an inductor. The capability of memorizing its resistance makes its useful for designing of non volatile memory and in neural networks. This paper aims at study of Memristors characteristics. We first analyze and model the characteristics of Memristor with HSPICE and then study its behavior for series and parallel combination.

Realization of Chaotic Circuits Using Lambda Diode

This paper presents the design of novel autonomous and non-autonomous inductorless chaotic circuit using lambda diode. The autonomous chaotic circuit is implemented using Chua’s circuit, where the piece-wise linear element of Chua’s circuit called Chua’s diode is replaced by lambda diode. The lambda diode used as a nonlinear resistor in Chua’s circuit comprises of BJT, FET and resistors. The non-autonomous chaotic circuit is studied by replacing the piece-wise linear element of Murali–Lakshmana–Chua (MLC) circuit by lambda diode. The reason for employing lambda diode is that it has a wide range of negative resistance characteristics, which enable the circuit to operate at higher frequency ranges. The resulting chaotic oscillator can easily be made to operate at both low and high frequencies. The chaotic behavior of the circuit is established through Multisim simulations in the time and frequency domains. Both theoretical analysis and electronic circuit experiments are presented. The circuit’s chaotic characteristics are further confirmed by means of Poincare plot and the Bifurcation diagram. The observed route to chaos is period-adding.