Input Double Output Research Articles

Parametric study of battery module cooling: Configuration optimization using response curve method

Recently, cylindrical lithium-ion battery cells have been widely used in electric vehicles due to efficient automated production and cheap kilowatt-hour capacity. For optimal operation of a cell, the internal temperature of the cell should be maintained within the range of 15–35 °C by employing suitable cooling mechanism. This study comprehensively compares multiple air-cooling configurations specifically designed for lithium-ion battery three-series and three-parallel (3S3P) modules using. The methodology involves an experimental phase to measure the parameters of Bernardi's equation, essential for calculating heat generation with consideration of both Joule's heat and entropic heat. Subsequently, a numerical simulation using Ansys Fluent examines battery heat generation within the 3S3P modules, employing diverse air-cooling configurations. Each configuration undergoes simulation with the aid of design of experiments and parametric analysis, allowing the observation of cooling behavior across various input parameters. To ensure reliability of simulation, the cooling of the unit cell module is simulated under similar conditions. The comparison between these simulated results and experimental values is conducted to validate the accuracy of the overall analysis methodology. The heat measurements indicated a unit cell heat output of 0.9028 W at an average rate of 0.85C. Among the investigated air-cooling configurations, the SIDO (Single Input Double Output) arrangement stood out as the most effective in maintaining a consistently lower average cell temperature, as determined through the application of the response curve method. This study emphasizes the importance of air-cooling design for improving the performance and safety of lithium-ion battery modules used in electric vehicles.

A Decoupling Control Method for Converting DIDO Sequence Admittance Model of Grid-Tied Converter System Into SISO

This paper proposes a decoupling control method to eliminate frequency coupling in three-phase grid-tied system. Firstly, the admittance model of three-phase <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LCL</i> -type three-phase grid-tied converter (GTC) considering DC-bus voltage control (DVC) loop and phase-locked loop (PLL) is established in <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">dq</i> -domain frame, and the influence of asymmetrical DVC and PLL control structure on frequency coupling oscillation is analyzed. Then decoupling factors are added to the DVC loop and current control (CC) loop to achieve that the off-diagonal elements of the sequence admittance matrix of the GTC are 0, which means the frequency coupling in the GTC is eliminated. Therefore, the GTC system can be regarded as a single input single output (SISO) system, and the stability can be analyzed by the classic Nyquist criterion in the sequence-domain frame. Compared with the double input double output (DIDO) system, the resulted SISO system convenient for calculating the stability margin of the system and guiding parameter design. In addition, the SISO system is easier to be analyzed on the oscillation and resonance mechanism, and the analysis results can be used to optimize the design of the converter controller, grid planning and operation. Finally, simulation and experiment verify the feasibility and effectiveness of the proposed decoupling control method.

Hybrid model predictive control for premixed natural gas engine as distributed generator

The access to electricity is increasing worldwide with a considerable growing rate per year. Unfortunately, traditional large fossil power technologies based on coal and oil lead to a major concern in environmental pollution, so the distributed power generation utilizing natural gas engine is taken into consideration. In this paper, a hybrid model predictive control (HMPC) strategy is proposed for natural gas engines in distributed power generation. The original fourth-order double-input double-output (DIDO) nonlinear engine model is transformed into two simpler models, one is a first-order model for air–fuel ratio (AFR) control, and a linear model predictive control (LMPC) strategy is designed. The other is a second-order nonlinear model for speed control, and the AFR is used as one of its two inputs to design nonlinear model predictive control (NMPC) strategy. The advantage of this is that each model is simpler than the original fourth-order model, and prediction horizon can be lengthened to achieve better control performance. For the optimization problem of NMPC, a switching mechanism strategy is proposed. It can effectively reduce the number of SQP iterations in both transient and steady-state conditions. Both simulations and experiments verify the feasibility of the HMPC and the effectiveness of the switching mechanism.

A Novel Single Coupled-Inductor Boost TPC With Two Inductively Interfaced Ports Suitable for Renewable Energy Integration

Three Port Converters (TPCs) are extensively used for renewable energy systems (RES) catering to stand-alone load and/or grid. Such systems require an energy storage element (ESE) which necessitates the TPCs to operate in both Single Input Double Output (SIDO) as well as Double Input Single Output (DISO) modes. Further, the ports connecting RES and ESE should preferably be inductively interfaced facilitating low ripple current for enhancing power extraction from RES, and for extending the lifetime of ESE. Single Inductor-based TPCs, despite offering high power density, lack inductively interfaced ports. To address the aforesaid issue, this paper proposes a single coupled inductor-based TPC in which RES and ESE are inductively interfaced. This solution is named Coupled Inductor Based Three-Port Converter (CIBTPC) and is derived by coupling the inductors of an existing three-switch boost TPC. CIBTPC offers the following advantages over its uncoupled counterpart: (a) reduced ripple current with the same core size and (b) improvement in overall efficiency. The operation of CIBTPC is illustrated by implementing a solar Photovoltaic (PV) based DC stand-alone and nano-grid scheme with battery backup. Validation and performance analysis of the overall system is carried out utilizing a 400W experimental prototype.

Nonlinear Active Disturbance Rejection Control of VGT-EGR System in Diesel Engines

In this paper, a nonlinear active disturbance rejection control (NLADRC) strategy based on nonlinear extended state observer (NLESO) is proposed to solve the unmodeled dynamics, coupling and disturbance due to change of working point in the variable geometry turbine (VGT) and exhaust gas recirculation (EGR) system, so as to achieve accurate control of intake manifold pressure and mass air flow in a diesel engine. To achieve decoupling, the double-input double-output (DIDO) VGT-EGR system is decomposed into two single-input single-output (SISO) subsystems, and each subsystem has a separate nonlinear active disturbance rejection controller. At the same time, the convergence proof of the designed NLESO is also given theoretically. Finally, the NLADRC controller is compared with linear active disturbance rejection controller and proportional–integral–derivative (PID) controller. Through simulation, it is indicated that the proposed NLADRC controller has better transient response performance, resistance to external disturbance and robustness to the change of engine operating point.

Emulation circuits of fractional-order memelements with multiple pinched points and their applications

Abstract This paper proposes voltage- and current-controlled universal memelements emulators. They are employed to realize the floating and grounded fractional-order memelements. The proposed emulators are implemented using different active blocks such as the second-generation current conveyor (CCII), Differential input double output transconductance amplifier (DOTA + ), balanced output CCII, and Differential voltage current conveyor (DVCC) with analog voltage multiplier. One of the main characteristics of the memristive elements is hysteresis loop behaviour with one pinched point, and the higher-order memelements have multiple pinched points. The higher fractional-order memductance (FOM) and inverse memductance (FOIM) emulators are proposed, which achieve multiple pinched-off points. The coordinates of the multiple pinched-off points and the conditions to achieve them are discussed in the I-V plane. Additionally, the effect of different orders α of the fractional-order capacitor (FOC) on the memelements characteristic is discussed. The circuit simulations for the proposed emulators have been verified using PSPICE simulations and validated experimentally at different orders. Finally, the grounded proposed emulator is employed in Chua's chaotic oscillator as an application presenting the effect of fractional-order on the chaotic response. Also, the floating proposed emulator is applied to a relaxation oscillator, to show the reliability of the proposed emulator.

On cross-correlogram IRF’s estimators of two-output systems in spaces of continuous functions

In this article, single input–double output linear time-invariant systems are studied. Both components of system’s impulse response function are supposed to be real-valued and L 2-integrable. One component is unknown while the second one is controlled. The problem is to estimate the unknown component after observations of the other component. For this purpose, we apply cross-correlating of the outputs given that the input is a standard Wiener process on R. Weak asymptotic normality of appropriately centered estimators in spaces of continuous functions is proved. This enables us to construct confidence intervals in these spaces. Our results employ techniques related to Gaussian processes and bilinear forms of Gaussian processes.

Behavioral Model of RF PAs Including Load Mismatch Effects Based on Canonical Section-wise Piecewise-Linear Function

A new, dynamic, double-input, double-output (DIDO), wideband, dynamic, complex envelope, behavioral model for power amplifiers (PAs), accounting for load mismatch effects, is proposed and validated in this paper. The model is constructed based on two-dimensional, dynamic, canonical section-wise piecewise-linear functions (2-D DCSWPL). Compared with existing DIDO behavioral modeling methods, which are almost all exclusively based on polynomial functions, the proposed model permits a vastly extended modeling space for PAs under load mismatch conditions. Experimental examples are given to validate the proposed modeling technique with a 15 W GaN PA under a wide range of output mismatch conditions, driven by a 5 MHz LTE signal. The proposed model shows an average accuracy improvement of 2 dB when compared with the more traditional DIDO memory polynomial (MP) models. In addition, the load reflection-dependent dynamic 2-D CSWPL modeling technique for PAs under mismatch condition is also provided. Compared with load-dependent MP, load-dependent crossover MP (COMP) and load-dependent DIDO MP models, the proposed model shows superior accuracy. Thus, the proposed modeling technique is an excellent choice for the modelling of PA systems that are subject to load mismatch effects.

Adaptive Control for Fast EDM Drilling of High Aspect-Ratio Holes

Fast EDM (electrical discharge machining) drilling is a powerful machining technique dedicated for small hole machining (0.2mm~3mm in diameter). It employs rotary tubular electrode and water-based dielectric fluid with high-pressure inner flushing. Owing to the enhanced inner flushing, evacuation of debris from the discharge gap becomes much easier. Therefore it can achieve higher machining efficiency than conventional sinking EDM and is capable of drilling high aspect-ratio (100:1 and higher) holes. It has now been widely used to drill small holes in manufacturing industries such as molds & dies, filters, automotive and aerospace parts. Fast EDM drilling process is a typical time-variant process, especially when drilling high aspect-ratio holes. The machining condition changes with time as the electrode goes deeper, since the evacuation of debris becomes increasingly difficult and the machining condition deteriorates. The conventional control system of the process determines the feedrate by average gap voltage with its parameters unchanged during the process. Such control systems become less efficient when drilling high aspect-ratio holes. In this paper, an adaptive control system for fast EDM drilling is proposed to deal with this complex process. The controlled plant is considered as a double-input double-output (DIDO) system. The inputs are the servo-reference voltage and the gain of the original controller, and the outputs are the ratio of normal discharge state (NDR) and its variance in a time interval. The servo-reference voltage is a key parameter for the control of the process, while the gain determines the actual feedrate along with the servo-reference voltage. The adaptive control system first estimates the parameters of the controlled plant model, and then automatically adjusts the two inputs according to current outputs and desired ones. The time-variant parameters of the controlled plant are estimated by the recursive least squares (RLS) method with a forgetting factor. And the multivariable generalized minimum variance method is used to obtain the control law of the two inputs. Experiments were conducted to verify the effectiveness of the controller, where 40-mm-deep holes were drilled by electrodes with a diameter of 0.4 mm (aspect-ratio 100:1). The results show that the machining state was improved by the adaptive controller especially in the later stage of the drilling process. NDR was higher and short circuits were suppressed. Results show that machining time was reduced by 11.3% and tool wear was also reduced by 3.0% with the adaptive controller.

An all-dielectric 3D Luneburg lens constructed by common-vertex coaxial circular cones

An all-dielectric broadband 3D Luneburg lens has been designed and manufactured in our study, which is constructed by common-vertex coaxial circular cones. A prototype of the lens is fabricated using 3D printing technology. The far field of the, present lens is highly directive, incident waves are focused with highly concentration, and its operating frequency spans from 5 GHz to 20 GHz. It is also found that two highly directional beams are generated while two independent converged sources feed simultaneously at the edge of the lens. The intersection angle with the center of the lens is 90°, which indicates that the lens is an efficient double input-double output device.

A novel single input double output (SIDO) converter for torque ripple minimization in solar powered BLDC motor

This paper proposes a new converter topology for torque ripple reduction in Brushless DC (BLDC) motor. Due to the torque ripple problem, the use of this motor is limited to few applications. In this paper, a Single Input Double Output (SIDO) converter is proposed to suppress the torque ripple in BLDC motor. The proposed SIDO converter provides two output voltages. One for supplying the motor throughout conduction time and second output voltage is given to the non-commutating phase of motor during commutation instants. This proposed SIDO converter is fed from Photo Voltaic (PV) system. This paper also presents a new Maximum Power Point Tracking (MPPT) based on trisection of Power-Voltage characteristics (TPVC) to attain the maximum power from the PV system. This scheme takes only 7 iterations to reach MPP. The intended configuration is developed and simulated in Matlab/Simulink environment. The results justify the superiority of proposed scheme that minimizes torque ripple in BLDC motor to only 6 to 12% from 50 to 80 % in conventional scheme and also extracts maximum power from PV system. ©2019. CBIORE-IJRED. All rights reserved

Estimation of impulse response functions in two-output systems

A single input–double output (SIDO) linear time-invariant (LTI) system is considered, whose impulse response function (IRF) is assumed to have one unknown component. The problem is to estimate this unknown component after observations of the second component. Both IRF’s components are supposed to be L2-integrable, and the estimation is made by cross-correlating the outputs, given that the input is a standard Wiener process on R. Weak asymptotic normality of appropriately centred estimators is proved.

Ultrabroadband Three-Dimensional Printed Radial Perfectly Symmetric Gradient Honeycomb All-Dielectric Dual-Directional Lightweight Planar Luneburg Lens

An ultrabroadband all-dielectric planar Luneburg lens has been designed and fabricated in this study, which is in the form of a radial gradient lightweight honeycomb column. Because of the novel design of a radial symmetric honeycomb-like microstructure in the subwavelength dimension and the radial gradient configuration according to the refractive index distribution of Luneburg lens, the present lens can focus incident plane waves on the opposite side with high convergence, and its operating frequency range is rather broadband, spanning from 6 to 16 GHz. Besides, the all-dielectric honeycomb-like lens is lightweight with a mass density of 0.23 g/cm3, and its broadband transmittance is higher than the reported cases consisting of metallic metamaterial or gradient photonic crystal structures. A prototype of the lens is fabricated by using 3D printing techniques, on which the electric near-field distribution and far-field radiation pattern measurements have been carried out, and the aforementioned performances were demonstrated experimentally. It was also observed that for two point sources placed at the edge of the lens whose intersection angle with the center of the lens is 90°, the far-field radiation pattern was still kept highly directional, which means that the lens can generate two highly directional beams simultaneously, and is an efficient double input-double output device.

A Two-Port Nonlinear Dynamic Behavioral Model of RF PAs Subject to Wideband Load Modulation

This work presents a full two-port, i.e., double input-double output, behavioral modeling approach suitable for radio frequency power amplifiers (PAs) in the presence of dynamic load modulation (DLM). The formulation of the model, based on a first-order approximation of a modified Volterra series, accounts for the nonlinear distortion determined by large-signal operation under mismatched conditions, and also for the memory effects stimulated by a modulated PA input signal, or by the dynamic variations of the PA load. By following an exhaustive procedure defined in the frequency domain, the model of a general purpose commercial PA is extracted over 160 MHz of modulation bandwidth (BW) with nonlinear vector network analyzer measurements. Validation results under 20-MHz BW multisine excitation and injected 80-MHz BW multisine load modulation show improved prediction capabilities with respect to quasi-static or single-input descriptions, allowing for reliable system-level simulations in the presence of DLM.

A new complex envelope behavioral model for load mismatched power amplifiers

A new dual-input wideband dynamic Quadratic Poly-Harmonic Distortion (D-QPHD) model for unmatched power amplifiers (PAs) is proposed and validated in this article. Compared with the dynamic PHD (D-PHD) model, the new approach significantly improves the prediction accuracy. As the new model has reduced complexity, it is also more robust against possible rank deficiency problems, but still preserves accuracy, when compared with the recently proposed double-input double-output (DIDO) model. The parameters of the new model also have smaller magnitude distribution range compared with the DIDO model, which also improves the model robustness. Hence, it provides a good modeling choice for complex envelope DIDO modeling.

A New Double Input-Double Output Complex Envelope Amplifier Behavioral Model Taking Into Account Source and Load Mismatch Effects

This paper presents a double input-double output bilateral low-pass equivalent amplifier behavioral model that takes into account input source and output load termination mismatches. The model is intended for the system-level simulation of amplifier chains subjected to wideband modulated signals, since it can predict the device's input and output scattered waves and their memory effects, in a wide range of voltage standing wave ratios (VSWR). In addition, the model extraction methodology, and its associated laboratory test bench are discussed, noting the limitations of conventional setups for behavioral model extraction and validation. The model is validated comparing the predicted and measured data of a real 15 W GaN based PA circuit attached to different loads. The obtained results show that, in terms of normalized mean square error, this model can provide -30 dB for VSWR in comparison to a much poorer performance of the conventional single input-single output model.

Fast-Decodable MIDO Codes With Large Coding Gain

In this paper, a new method is proposed to obtain full-diversity, rate-2 (rate of two complex symbols per channel use) space-time block codes (STBCs) that are full-rate for multiple input double output (MIDO) systems. Using this method, rate-2 STBCs for 4 × 2, 6 × 2, 8 × 2, and 12 × 2 systems are constructed and these STBCs are fast ML-decodable, have large coding gains, and STBC-schemes consisting of these STBCs have a non-vanishing determinant (NVD) so that they are DMT-optimal for their respective MIDO systems. It is also shown that the Srinath-Rajan code for the 4 × 2 system, which has the lowest ML-decoding complexity among known rate-2 STBCs for the 4 × 2 MIDO system with a large coding gain for 4-/16-QAM, has the same algebraic structure as the STBC constructed in this paper for the 4 × 2 system. This also settles in positive a previous conjecture that the STBC-scheme that is based on the Srinath-Rajan code has the NVD property and hence is DMT-optimal for the 4 × 2 system.

Iterated Space-Time Code Constructions From Cyclic Algebras

We propose a full-rate iterative space-time code construction, which uses an algebraic space-time code in order to design a new space-time code of double the code rank. We give a condition for determining whether the resulting codes satisfy the full diversity property, and study their maximum likelihood decoding complexity with respect to sphere decoding. Particular emphasis is given to the asymmetric multiple input double output codes. In the process, we derive an interesting way of obtaining division algebras, and study their centers and maximal subfields.

CLASSIFICATION AND PATHOLOGICAL REALIZATIONS OF TRANSCONDUCTANCE AMPLIFIERS

Classification of transconductance amplifiers (TA) based on the number of input ports and output ports is given. A systematic generation method of TA based on using nullator, norator elements, and pathological mirror elements is used to provide pathological realizations of different types of TA. Four pathological realizations of the single input balanced output TA each using two grounded G are given. Four pathological realizations of the differential input single output TA each using two grounded G are given. Six pathological realizations of the differential input balanced output TA known as BOTA are given. Three pathological realizations for each of the two types of the differential input double output TA are also given. Finally, four alternative ideally equivalent realizations of the BOTA using two current conveyors (CCII) or two inverting current conveyors (ICCII) are generated from the pathological realizations.

Some complexity problems on single input double output controllers

We investigate the time complexity of constructing single input double output state feedback controller structures, given the directed structure graph G of a system. Such a controller structure defines a restricted type of P 3 -partition of the graph G . A necessary condition (∗) is described and some classes of graphs are identified where the search problem of finding a feasible P 3 -partition is polynomially solvable and, in addition, (∗) is not only necessary but also sufficient for the existence of a P 3 -partition. It is also proved that the decision problem on two particular graph classes — defined in terms of forbidden subgraphs — remains NP-complete, but is polynomially solvable on the intersection of those two classes. The polynomial-time solvability of some further related problems is shown, too.