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Determining the Marx generator configuration, including the values of series and parallel resistors as well as the number of series and parallel stages to obtain standard lightning impulse (LI) waveforms, is usually done in a trial and error process in the high voltage test fields of power transformer manufacturers. This practical process may take excessive time and is boring for test engineers. In this paper, a simple simulation method is proposed to model the LI test circuit of the transformer by computer, which is helpful in identifying the Marx generator set up. This method is based on modeling the LI test circuit as well as the transformer's high frequency impedance in discrete frequency domain. The measured frequency response of the transformer is used to model its high frequency characteristics. Digital signal processing methods are used to simulate the circuit and obtain waveforms. The accuracy of the proposed method is validated using experimental tests performed on three transformers with different ratings. [ABSTRACT FROM AUTHOR]

In this paper, we propose a novel Verilog-A based memristor model for effective simulation and application. Our proposed model captures desired nonlinear characteristics using voltage-based state control. This model is flexible and accurate, it can exhibit all the behaviors of HP memristive device and a general class memristive device resistive random access memory which is important in logic and memory design. Furthermore, we can antiserially connect two proposed models to capture the ideal I – V characteristics of complementary resistive switch (CRS). We demonstrate that our proposed CRS model-based crossbar arrays can significantly reduce sneak path currents with high noise margin compared to traditional memristor-based architectures. [ABSTRACT FROM AUTHOR]

The Cauer ladder network (CLN) method provides an efficient representation of eddy-current fields. This paper proposes a reformulation of the CLN method that considers expansion points using the magnetic/current vector potential. To cover a wide range of frequencies, the expansion point may be changed at a later stage of the network. Only a few stages of the ladder network are required for the eddy-current field to be reconstructed accurately around the target frequency using the expansion points. [ABSTRACT FROM AUTHOR]

In this paper, a new synchronous machine model is developed for electromagnetic transients program type simulations. The stator circuit is expressed in the abc phase domain. The machine model is represented as a Norton equivalent with a current source in parallel with a constant Norton admittance. The machine equations are reformulated so that the computational effort required for the modeling of the machine is reduced. Test studies demonstrate the accuracy of the proposed synchronous machine model and show that the proposed model is computationally more efficient than the existing constant conductance phase domain model and voltage-behind-reactance model. [ABSTRACT FROM AUTHOR]

In this paper, a new continuous multilevel compact model for phase-change memory (PCM) is proposed. It is based on the modified rate equations with the introduction of a variable related to material melting. The model is evaluated using a large set of dynamic measurements and shows a good accuracy with a single model card. All fitting parameters are discussed, and their impacts are detailed. Full circuit simulation is performed. Good convergence and fast simulation time suggest that this new compact model can be exploited for PCM circuit design. [ABSTRACT FROM AUTHOR]

In this paper, we propose an efficient model for dynamic self-heating and thermal coupling in a multifinger transistor system. Essentially, the proposed model is an improvement over a state-of-the-art existing model from the viewpoint of simulation time. Verilog-A implementation of the proposed model does not require to use any voltage controlled voltage source. In a multifinger transistor system, with $n$ emitter fingers, our model uses 3n$ extra nodes in Verilog-A implementation whereas it is 2n^{2}-n for the state-of-the-art model. Note that our model requires no extra nodes for implementing the thermal coupling effects. We present that the transient simulation results of our model are identical with those of the state-of-the-art model. Electrothermal simulation using the proposed thermal model shows good agreement with the measured data. It is found that the proposed model simulates more than 40% faster compared with the existing model for a ring oscillator circuit. [ABSTRACT FROM AUTHOR]

Accurate estimation of power capacity is critical to ensure battery safety margins and optimize energy utilization. Power capacity estimators based on online identified equivalent circuit model have been widely investigated due to the high accuracy and affordable computing cost. However, the impact of noise corruption which is common in practice on such estimators has never been investigated. This paper scrutinizes the effect of noises on model identification, state of charge (SOC) and power capacity estimation. An online model identification method based on adaptive forgetting recursive total least squares (AF-RTLS) is proposed to compensate the noise effect and attenuate the identification bias of model parameters. A Luenberger observer is further used in combination with the AF-RTLS to estimate the SOC in real time. Leveraging the estimated model parameters and SOC, a multiconstraint analytical method is proposed to online estimate the power capacity. Simulation and experimental results verify that the proposed method is superior in terms of estimation accuracy and the robustness to noise corruption. [ABSTRACT FROM AUTHOR]

Radiation-induced single event transients (SETs) are expected to evolve to single event multiple transients (SEMTs) due to the downscaling of transistor feature size, which also increases the difficulty of the vulnerability estimation for large-scale digital integrated circuits. In this paper, a novel layout-based soft error vulnerability estimation approach which is termed LBSEVEA is proposed to evaluate the impact of heavy ions on the vulnerability of combinational circuits. The physical process of interaction between particles and devices, especially nuclear reaction and scattering process are included in the LBSEVEA. In addition, ambipolar diffusion and bipolar amplification effect, which induce additional charge collection of the adjacent transistors and the hitting transistor, are also considered. A new method calculating the collected charge induced by the bipolar amplification effect is presented. By introducing the layout information of the target circuits into the identification of the adjacent cells, SEMTs effect can be considered in the vulnerability estimation. A fast SPICE simulation tool is adopted to conduct the fault injected netlist simulations, which can make a favorable compromise between the consumption of computer resources and simulation precision. Furthermore, induced soft error numbers, distributions of charge collected by the hitting nodes and the adjacent nodes, and SET pulse width distributions are presented. Besides, heatmaps of induced pulse widths for the layout of two benchmark circuits are provided. Finally, the constraints, the flexibility, and the scalability of the LBSEVEA are discussed. The ability to estimate the impact of process variations on the vulnerability is also presented. Compared with simulation and experimental results, the LBSEVEA can fairly estimate the vulnerability of combinational circuits. [ABSTRACT FROM AUTHOR]

Studying the propagation of harmonics in power grids represents a very important task nowadays. However, this demands for nonlinear models of power system devices representing a critical tradeoff between the accuracy and the computational cost. Simplified Volterra models with quasi-sinusoidal excitation have been recently proposed and they appear to be particularly suitable for the purpose. In this paper, these models have been applied to predict, for a given input voltage, the current harmonics of a full-bridge rectifier feeding an ohmic-capacitive load. Accuracy has been evaluated by means of both numerical simulations and experiments. Robustness has also been assessed by considering a set of realistic voltage waveforms different from those employed for the identification. Results highlight the remarkable accuracy of the proposed models in spite of the relatively small set of coefficients to be identified. This feature is extremely important when models have to be employed in frequency-domain simulations of large networks. [ABSTRACT FROM AUTHOR]

This paper presents a three-dimensional electrothermal numerical model of the medium voltage outdoor circuit breaker. The model was validated by heat run test performed under the conditions required by IEC 62271-1 and IEC 62271-100 standards, as well as some other specific requirements related to the breaker overload under low ambient temperature conditions and natural cooling. The purpose of this study was to build a numerical model of the medium-voltage circuit breaker that could be successfully applied for the redesign of the breaker for more demanding operating conditions with minimum physical test iterations. The numerical results obtained were found to be in a good agreement with experimental values having the average discrepancy of 3 K with the maximum below 5 K on busbars. [ABSTRACT FROM AUTHOR]

Considering the demand of III–V multigate (MUG) transistors for next-generation CMOS technologies, a compact model is required to test their performance in different circuits. The low effective mass and highly confined geometry of these MUG devices demand the use of computationally expensive coupled Poisson–Schrödinger (PS) solver for terminal charges and surface potential. In this paper, we propose an approximation, which decouples the PS equations and enables the development of a computationally efficient analytical model. The surface potential and semiconductor charge equations for III–V low effective mass channel cylindrical nanowire (NW) transistors are derived using the proposed approximation. The proposed model is physics-based and does not include any empirical parameters. The accuracy of the model is verified across NWs of different sizes and materials using the data from the 2-D PS solver and found to be accurate. [ABSTRACT FROM AUTHOR]

Low-watt compact fluorescent lamps (CFLs) may account for significant energy consumption of power distribution feeders in future years. This can lead to power-quality concerns because these devices consume highly distorted currents. In order to predict CFL harmonic current emissions into networks, CFL models capable of predicting these emissions accurately are being studied. On the other hand, these models require great computational effort in large-scale CFL penetration studies. This paper presents and discusses several approximate CFL models based on the harmonic-coupled admittance matrix model which reduces the computational effort while maintaining reasonable accuracy. The performance of the models is validated with CFL laboratory measurements. [ABSTRACT FROM AUTHOR]

Defects or traps in semiconductors and nano devices that randomly capture and emit charge carriers result in low-frequency noise, such as burst and $1/f$ noise, which are important concerns in the design of both analog and digital circuits. The capture and emission rates of these traps are functions of the time-varying voltages across the device, resulting in nonstationary noise characteristics. Modeling of low-frequency, nonstationary noise in circuit simulators is a long-standing open problem. It has been realized that the low-frequency noise models in circuit simulators were the culprits that produced erroneous noise performance results for circuits under strongly time-varying bias conditions. In this paper, we present two fully nonstationary models for traps, a fine-grained Markov chain model and a coarse-grained Langevin model based on similar models for ion channels in neurons. The nonstationary trap models we present subsume and unify all of the work that has been done recently in the device modeling and circuit design literature on modeling nonstationary trap noise. We provide a detailed explication of these models with regard to their stochastic properties and develop carefully crafted circuit simulation techniques that are stochastically correct. We have implemented the proposed techniques in a MATLAB-based circuit simulator, by expanding the industry standard compact MOSFET model PSP to include a nonstationary description of oxide traps. We present results obtained by this extended model and the proposed simulation techniques for the low-frequency noise characterization of a common source amplifier and the phase jitter of a ring oscillator. [ABSTRACT FROM PUBLISHER]

This paper presents a comprehensive and modular modeling framework for stochastic signal integrity analysis of complex high-speed links. Such systems are typically composed of passive linear networks and nonlinear, usually active, devices. The key idea of the proposed contribution is to express the signals at the ports of each of such system elements or subnetworks as a polynomial chaos expansion. This allows one to compute, for each block, equivalent deterministic models describing the stochastic variations of the network voltages and currents. Such models are synthesized into SPICE-compatible circuit equivalents, which are readily connected together and simulated in standard circuit simulators. Only a single circuit simulation of such an equivalent network is required to compute the pertinent statistical information of the entire system, without the need of running a large number of time-consuming electromagnetic circuit cosimulations. The accuracy and efficiency of the proposed approach, which is applicable to a large class of complex circuits, are verified by performing signal integrity investigations of two interconnect examples. [ABSTRACT FROM PUBLISHER]

Analog components are fundamental blocks of smart systems, as they allow a tight interaction with the environment, in terms of both sensing/actuation and communication. This impacts on the design of the overall system, and mainly on the validation phase, that thus requires the joint simulation of digital and analog aspects. In this scenario, this paper proposes the automatic conversion of analog models to C++-based languages, to remove the overhead of co-simulation with traditional virtual platform tools. The proposed methodology allows to convert a given analog description to either: 1) a fully equivalent description or 2) an abstract representation for faster simulation which models only the aspects of interest. Effectiveness and correctness have been proved on a number of case studies that highlight the effectiveness and potentiality of the proposed methodology. [ABSTRACT FROM AUTHOR]

The modular multilevel converter (MMC) has attracted extensive research in recent years. An appropriate model is necessary to analyze stability or to design MMC controllers. Several published MMC models have been derived in single-phase form to simplify the modeling mathematics. However, little attention is given to the zero-sequence voltage, which introduces coupling in the single-phase model and leads to significant error. In this paper, after revealing the mechanism behind the zero-sequence voltage, a more accurate generalized single-phase MMC model is proposed, which eliminates the zero-sequence voltage coupling effect and is linearized based on harmonic state space (HSS) theory to precisely characterize the internal harmonic features of MMC. A systematic HSS modeling process is presented for both open-loop and closed-loop conditions. And the proposed model is generalized as it can incorporate different control strategy by controller transfer function substitution. Hence it is valuable to analyze MMC stability and dynamics. Model effectiveness is verified by simulation results. [ABSTRACT FROM AUTHOR]

Among different modular multilevel converter (MMC) submodule (SM) topologies, the clamp double submodule (CDSM) has the capability of dc fault current limiting and utilizes a relatively small number of switching devices. Since CDSM has a more complex circuit structure than half-bridge or full-bridge SM, it is a significant challenge for the real-time electromagnetic transient (EMT) simulation for a multiterminal dc (MTDC) system containing CDSM MMC. This paper proposes the device-level electrothermal model of CDSM for real-time EMT simulation, which can accurately present the power losses, the junction temperatures, and the switching transient waveforms of individual switches consuming more computation resources. The individual insulated-gate bipolar transistors of the CDSM MMC during fault clearance transient are evaluated from both electromagnetic and thermal perspectives, which interact with each other dynamically. To ensure the real-time performance of the proposed model, the equivalent circuit model is combined with the device-level model. The system-level and device-level waveforms during normal operation and dc fault transient for a three-terminal dc system are both presented and compared with PSCAD/EMTDC and SaberRD. The simulation system was implemented on the Xilinx Zynq UltraScale+ ZCU102 multiprocessor system-on-chip (MPSoC) platform, and the results were captured by the oscilloscope in real-time. [ABSTRACT FROM AUTHOR]

Modeling partially shaded photovoltaic (PV) systems for online applications such as model-based MPPTs requires a PV circuit model with low computational time to simulate the large number of connected PV units within a reasonable amount of time. Unfortunately, the accurate PV models available in the literature are complex and suffer from high computational time due to their dependence on a transcendental implicit equation. This paper proposes a photovoltaic circuit model featuring lower computational time and comparable accuracy. The model utilizes the accuracy of the practical PV model and reduces the computational time by replacing the model series resistance with a third-degree-polynomial voltage-dependent source. The proposed model mimics the accurate characteristics of the practical model without being dependent on a transcendental implicit equation, thus providing low computational time. The model also introduces a new parameter to enhance the model's accuracy at low irradiance. The effectiveness of the model is shown by comparing the computational time and accuracy of the proposed model with those of the available models. A case study of partially shaded PV systems shows that the percentage of reduction in computational time improves with increases in the number of PV units in a simulated PV system, providing a clear advantage when simulating large PV systems. [ABSTRACT FROM PUBLISHER]

This paper proposes a method for estimating two inductances and capacitance of an LCL filter, connected between a converter and a grid. Only the dc-bus voltage and converter phase currents need to be measured. An excitation signal is fed into the converter voltage reference. The fundamental and selected harmonic components are removed from the stored identification data to prevent biases in the parameter estimates. The parameters of the hold-equivalent discrete-time model are estimated recursively. The inductance and capacitance estimates are calculated from the estimated discrete-time parameters using the corresponding closed-form model. The proposed method can be added to the existing converter control algorithms. It can provide the parameter estimates for the converter control. Further, it can be run occasionally during the normal operation in order to obtain an updated grid inductance estimate. Experimental results show that the proposed method yields very good parameter estimates and that it can also detect the changes in the grid inductance. [ABSTRACT FROM PUBLISHER]

The model of a modular multilevel converter (MMC) determines the extent of critical circuit information that electromagnetic transient simulations can reveal. In this paper, two MMC models are proposed for efficient real-time hardware-in-the-loop (HIL) emulation on the field-programmable-gate-arrays (FPGA). The nonlinear switch-based model employing the insulated-gate bipolar transistor (IGBT) dynamic curve-fitting model considers factors affecting its transient performance so that device-level behavior such as power loss and junction temperature can be reproduced accurately in the electro-magnetic-thermal simulation of a power converter for its design evaluation. Meanwhile, regarding the MMC submodule as a transmission line stub achieves faster computation speed and enables the formation of a hybrid arm to save FPGA hardware resources. As the large network that the MMC presents is burdensome for real-time execution with a small time-step, circuit simplification based on partitioning and merging is conducted. Hardware implementation of a three-terminal high-voltage direct-current system containing an MMC-based dc–dc converter is carried out and the efficacy of proposed models is validated by comparing HIL emulation results with the offline simulation tool PSCAD/EMTDC. [ABSTRACT FROM AUTHOR]

State-of-health estimates of batteries are essential for onboard electric vehicles in order to provide safe, reliable, and cost-effective battery operation. This paper suggests a method to estimate the 10-s discharge resistance, which is an established battery figure of merit from laboratory testing, without performing the laboratory test. Instead, a state-of-health estimate of batteries is obtained using data directly from their operational use, e.g., onboard electric vehicles. It is shown that simple dynamical battery models, based on a current input and a voltage output, with model parameters dependent on temperature and state of charge, can be derived using AutoRegressive with eXogenous input models, whose order can be adjusted to describe the complex battery behavior. Then, the 10-s discharge resistance can be conveniently computed from the identified model parameters. Moreover, the uncertainty of the estimated resistance values is provided by the method. The suggested method is validated with usage data from emulated electric vehicle operation of an automotive lithium-ion battery cell. The resistance values are estimated accurately for a state-of-charge and temperature range spanning typical electric vehicle operating conditions. The identification of the model parameters and the resistance computation are very fast, rendering the method suitable for onboard application. [ABSTRACT FROM PUBLISHER]

This paper presents an analytical time-domain-based parameter identification method for Thévenin-equivalent circuit-based lithium-ion battery models. The method is based on the analysis of voltage-relaxation characteristics of pulse discharge and pulse charge experiments, and the method can be used for both discharge and charge operation with any number of parallel resistor-capacitor branches. The use of the method is demonstrated for a second-order model and validated with a real-world duty cycle. Experimental results for a commercial lithium-ion battery module are presented. [ABSTRACT FROM PUBLISHER]

A reliable model to analyze the dynamic behavior of two-phase switched-capacitor dc–dc converters in the slow-switching limit regime is proposed, taking into account both top and bottom parasitic capacitances as well as the charge reusing approach. This technique features significant improvements in both gain and efficiency with respect to existing solutions. We calculate the slow-switching limit boundary layer taking into account the parasitic capacitances of the flying capacitors and the dynamic and parasitic effects from the switches. The model is highly reliable into this region, featuring better accuracy in both time response and charge consumed than previous models in the literature. Also, as we will show that it can be used outside this region assuming a certain accuracy loss. The model is verified by experimental results and circuit-level simulations. The model has been implemented in an open-access web simulator, saving up to 10 000$\times$ in computation time when compared to well-known circuit-level simulators. The applicability of the model is illustrated through the optimization of charge efficiency and time response in a typical situation for light microenergy harvesting using Dickson, Fibonacci, and exponential solutions. [ABSTRACT FROM AUTHOR]

The Proper Orthogonal Decomposition (POD) combined with the (Discrete) Empirical Interpolation Method (DEIM) can be used to reduce the computation time of the solution of a Finite Element (FE) model. However, it can lead to numerical instabilities. To increase the robustness, the POD_DEIM model must be constructed by preserving the structure of the full FE model. In this paper, the structure preserving is applied for different potential formulations used to solve electromagnetic problems. [ABSTRACT FROM AUTHOR]

Six-phase electrical machines have received significant attention in the literature due to their use in special purpose applications (e.g., aircraft, naval, and vehicular systems). Recently, such machines have also been considered for renewable energy systems including wind generators. Modeling of such machines in commonly available transient simulation programs is not straightforward, especially when the machine model is interfaced with external inductive network and/or power electronic converters. The available modeling approaches include the classical qd 0 model, the coupled-circuit-phase-domain and the voltage-behind-reactance (VBR) models (each having its interfacing challenges). This paper extends the prior research in this area and proposes a constant-parameter VBR model that has a very convenient constant RL−branch interfacing circuit (even for salient pole machines), which makes it simple to implement in most state-variable-based simulations programs. The presented computer studies demonstrate significant numerical advantages of the new model over the existing alternative models. [ABSTRACT FROM PUBLISHER]

A physics-based simple and accurate compact model of drain current for GaN-based high electron mobility transistors (HEMTs) is presented. The model is developed using analytical relations for charges in the 2-D electron gas and barrier layer. For the first time, a simple charge linearization approach has been used for GaN-based HEMTs. The access regions are accurately modeled using transistors. The model is rigorously validated over a wide range of geometries and parameters for AlGaN/GaN and AlInN/GaN HEMTs. The model also passes the DC Gummel symmetry test. [ABSTRACT FROM AUTHOR]

The operational efficiency of ultrafast actuators used as drives in high-voltage direct-current breakers is at best 5%. To boost their efficiency, the design of the energizing circuit is crucial. A multiphysics finite-element method model coupled with a SPICE circuit model that is able to predict the performance of the actuator with an accuracy of at least 95% has been developed and verified experimentally. Several variants of prototypes and models have been simulated, built, and tested. It was shown that one of the main problems leading to low efficiencies is the stroke of the drive. However, there is a possibility to increase the efficiency of the electric to mechanical energy conversion process of the studied Thomson coil (TC) and double-sided coil (DSC) to a maximum of 54% and 88%, respectively, if their stroke is minimized. These efficiencies are idealistic, and these were obtained with clamped armature studies. The efficiency of the actuator can be increased at the expense of increasing the complexity and the cost of the contact system by designing a switch with several series-connected contacts that is encapsulated in a medium with a high dielectric strength. Another proposed solution is to design a current pulse with a rise time that is considerably shorter than the mechanical response time of the system. Parametric variations of capacitances and charging voltages show that the TC and the DSC can achieve efficiencies up to 15% and 23%, respectively. Regardless of the chosen method, the DSC has a superior efficiency compared to a TC. [ABSTRACT FROM PUBLISHER]

Transformer manufacturers make routine use of white-box detailed transformer models for ensuring that the transformer will pass the lightning impulse test. For use in general simulation studies, the model should additionally be multiphase and properly reproduce the transformer's input impedance characteristics and voltage ratios at 50/60 Hz. One challenge in such general modeling scope is to properly represent the frequency-dependent damping of the transformer's many resonances. In this work, we show how to properly include empirical damping factors in a multiphase admittance-based formulation of the state-equations. It is shown that the substitution of the real part of the state matrix eigenvalues causes some undesired changes to the model's behavior at lower frequencies, but this deficiency is mitigated by a correction to the output matrix. The resulting model can be directly included in EMTP-type simulation programs via a companion model, or via a terminal model with an add-on model for optional calculation of selected internal node voltages. Application of the modeling approach to a single-phase three-winding transformer demonstrates its merit in terms of accuracy and efficiency. Finally, the limitations of the model are discussed regarding accuracy and applications scope. [ABSTRACT FROM AUTHOR]

We propose an explicit surface-potential-based direct current (dc) model for fully depleted polysilicon (poly-Si) thin-film transistors (TFTs). Being analytical and explicit, the proposed model is a solid base for compact models of these devices. The essential for our model is the explicit calculation of the surface potential, using the Lambert W function. Subsequently, using the surface potential, we also develop the expressions for charge and current, employing well established approaches, which include integration of carrier’s charge for drain current. Furthermore, the solutions of surface potential and drain current were validated by numerical results and experimental data, respectively. Finally, we discussed in detail about the effects on the surface potential and dc properties from the full depleted poly-Si TFT parameters. As a result, such a model is suitable to be implemented into computer-aided simulations of both device and circuit designs, due to its high computational accuracy and efficiency. [ABSTRACT FROM AUTHOR]

An approximate multiconductor transmission-line (MTL) model is developed for predicting the radiated susceptibility of bundles composed of twisted-wire pairs (TWPs) running above a ground plane, and illuminated by a nonuniform electromagnetic field. Through the use of averaged per-unit-length parameters and sampling of the incident electromagnetic field, the nonuniform MTL is modeled as an equivalent uniform MTL including common-mode (CM) voltage sources accounting for field-to-wire coupling effects. The proposed model is able to predict CM currents/voltages induced in the terminal loads of every TWP in the bundle. In particular, it is shown that the CM noise significantly differs depending on the position of the considered TWP in the bundle cross section. Comparison of results versus full-wave simulations validates accuracy and computational efficiency of the proposed model. [ABSTRACT FROM AUTHOR]

A modified particle swarm optimization algorithm for conducting near-real-time parameter estimation of an electrical model for lithium batteries is presented. The model comprises a dynamic capacitance for characterizing the nonlinear relationship between the battery electromotive force and the state-of-charge, and a resistor-capacitor network for characterizing the static and transient responses. The algorithm is confirmed by successfully determining all parameters in a predefined simulation model. It is also evaluated on a hardware test bed with two samples of 3.3-V, 40-Ah, Lithium Iron Phosphate (LiFePO4) battery driven under six different loading patterns. The intrinsic parameters are estimated by first processing 15-min samples of the battery terminal voltage and current. The whole process takes 2 min. Then, the voltage-current characteristics in the following 15 min are predicted. Results show that the extracted parameters can fit the first 15-min voltage samples with a maximum error of 16 mV and an average error of 3.8 mV. With the extracted parameters, the electrical model can predict voltage-current characteristics in the following 15 min with a maximum error of 31 mV and an average error of 15 mV. The algorithm is further verified by successfully determining the emulated variation of the output resistance. [ABSTRACT FROM AUTHOR]