Programmable Power Supply Research Articles

Transient Finite Element Simulation of a Lithium-Ion Battery Pack Thermal Management System Based on Latent Heat System Materials

Battery packs in high-intensity use run the risk of overheating, potentially inducing catastrophic thermal runaway. Thermal runaway occurs when an individual cell in a connected system fails and subsequently applies increased stress on the remaining cells, leading to cascading failures and destruction of the battery pack as a whole. One method for controlling battery temperature during usage is utilizing the battery pack casing as a latent heat system (LHS), specifically incorporating phase-change materials (PCMs). Using this method, the transient thermal response of a 84-cell, 270 V lithium-ion battery pack for an aircraft application was simulated using ANSYS FLUENT. Heat generation rates and specific heat capacity of a single cell were experimentally measured and used as input to the thermal and mechanical model. A heat generation load was applied to the entire battery pack, and natural convection film boundary conditions were applied to the exterior of the enclosure. The maximum temperature of the battery pack without any casing reached 69.8 ᵒC after 800 s of usage at a simulated peak power draw of 1013 W or 16 A. This exceeds the manufacturer’s maximum recommended operating temperature of 60 ᵒC. For other materials, we found the maximum temperature of the batteries reached 57.0 ᵒC with plastic casing and 45.0 ᵒC with aluminum casing. We present a design of the pack that incorporates a passive thermal management system using a composite material consisting of phase-changing material, Puretemp60®, mixed with expanded graphite (EG). Simulations of the battery pack showed a decrease in the maximum temperature with the Puretemp60® as the sole material reaching a maximum of 54.2 ᵒC and the Puretemp EG composite matrix having a maximum temperature of 51.1 ᵒC, both after 800 s at the same power draw.The optimal material combination was then determined through evaluating several PCM and EG composites in several ratios using ANSYS FLUENT, followed by experimental testing. The mixture was cost effective, easy to mix, and demonstrated good mechanical properties. Results illustrated that a mixture of 25% expanded graphite with 75% Puretemp60® (PCM) was capable of maintaining battery temperatures within the acceptable operating range under moderate load conditions and therefore preventing thermal runaway. A resulting weight reduction of about 23.5% was also achieved using the Puretemp EG composite matrix in comparison to aluminum casing, and about a 7.2% reduction compared to plastic casing.Differential scanning calorimetry (DSC) was utilized to determine the phase transformation of the composites. The addition of expanded graphite minimally affected the phase transformation temperature, while decreasing the latent heat of transformation by about 40%. Scanning electron microscope (SEM) pictures visualized the morphology of the graphite during each stage of the composite fabrication process. The Puretemp60® and expanded graphite were easily mixed and the backscattering electron images indicated the composition was homogenous.The heat generation rate of the battery was calculated using the q̇gen= mCp(dT/dt) + UA∆T. The change in temperature with respect to time was experimentally determined from a series of discharges. Heat generation in the batteries was modeled as uniformly distributed. The average of the experimentally measured heat generation rates for a 1P constant power discharge were divided by the volume of the battery to yield a curve for the average body heat flux load in W/m3 over the discharge of the battery. A polynomial curve fit to the average heat generation rates was applied as a heat load to each battery in the simulation. The heat generation due to discharge was tested with a setup where the battery was insulated in polyurethane foam in order to reduce convection heat transfer during the experiments. A polyurethane foam block was cut such that the battery could be placed in the center, along with three T-type thermocouples to measure the surface temperature and external air temperatures. Two metal cylinders, one consisting of copper and the other of 6061 aluminum, were machined to the same cylindrical dimensions as the battery. These cylinders were then used to determine the heat loss, or UA value, of the foam insulation block setup. A National instruments NI 9147, Chroma Programmable DC Power Supply, and LabView software were used for the experiments. Figure 1

Robust Flatness Tracking Control for the “DC/DC Buck Converter-DC Motor” System: Renewable Energy-Based Power Supply

The design of a robust flatness-based tracking control for the DC/DC Buck converter-DC motor system is developed in this paper. The design of the control considers the dynamics of a renewable energy power source that plays the role of the primary power supply associated with the system. The performance and robustness of the control is verified through simulations via MATLAB-Simulink when abrupt changes in some parameters of the system are taken into account. Also, experiments are performed by using a built prototype of the DC/DC Buck converter-DC motor system, a TDK-Lambda G100-17 programmable DC power supply, MATLAB-Simulink, and the DS1104 board from dSPACE. In this regard, the TDK-Lambda G100-17 is implemented with the aim of emulating photovoltaic panels through the solar array mode for generating the power supply of the system. Thus, both simulations and experiments show the effectiveness of the proposed control scheme.

A High-Precision and Wideband Fundamental Frequency Measurement Method for Synchronous Sampling Used in the Power Analyzer

In the dedicated high-precision power quality analyzer, synchronous sampling is required to reduce the effect of spectrum leakage produced by the discrete Fourier transform process. Thus, accurate fundamental frequency measurement is urgently needed. However, due to the harmonics and noise in the power signal, it is difficult to achieve the accurate fundamental frequency measurement. Moreover, with the wide application of high-frequency programmable power supply, the fundamental frequency is gradually increasing, which requires power analyzers to have the abilities of both high precision and a wide range of the fundamental frequency measurement. To solve these issues, a new fundamental frequency measurement architecture used in synchronous sampling is proposed. This architecture consists of a small-point fast Fourier transform module, spectrum refinement algorithm, and a multimodal optimization method to calculate the accurate fundamental frequency under large harmonic conditions. In the practical hardware platform results, this architecture has a large fundamental frequency measurement range from 20 Hz to 200 kHz with a relative error which is <0.004%. The wideband fundamental frequency measurement structure proposed in this article achieves high measurement accuracy.

Shrinkage rate control during a flash state by current‐ramping for 3 mol% Y2O3‐doped ZrO2 polycrystals

Abstract3 mol% Y2O3‐doped ZrO2 green compacts with rectangular shapes were sintered by maintaining the shrinkage rates at constant values under alternating electric fields by ramping the electric current during flash states. Green compacts were furnace‐heated under 40‐100 Vrms/cm until current hits an initial current limit of 100 mArms. After then, current‐ramping was started to keep the shrinkage rates constant by increasing the limit current value using a programmable power supply operating in a current control mode. Highly densified 3 mol% Y2O3‐doped ZrO2 polycrystals with a density of 6.05 g/cm3 as a bulk density and a grain size of about 0.4 μm were obtained at a furnace temperature of about 930℃, 50 Vrms/cm with 1000 Hz and shrinkage rate of about 120 μm/min (0.8%/min against initial lengths of green compacts). The Vickers hardness and indentation fracture toughness of the compact exhibit similar values to those obtained from thermally sintered compacts.

An innovative torsional vibration absorber of vehicle powertrain system: Prototype design, performance test, and control experiment

A dynamic vibration absorber can effectively reduce the vibration of a mechanical system, and designing a new type of torsional vibration absorber to reduce the torsional vibration of the vehicle powertrain system and establishing relevant experiments to test its vibration reduction performance are necessary. This article presents a detailed design and manufacturing process of an innovative torsional vibration absorber with magnetorheological elastomers (MREs) as its core intelligent element. A series of experiments are carried out to evaluate the vibration reduction performance of the new vibration absorber. A vibration reduction performance experiment with a torsional vibration exciter is used to test the vibration transmissibility of the vibration absorber, and the frequency shift range is identified. An engine vibration reduction performance experiment is carried out to verify the feasibility of the vibration absorber in actual powertrain systems, and its good vibration reduction effect is also proven by comparative experiments. A semi-active control experiment of the vibration absorber is performed to verify the reliability of the programmable power supply and the conductive slip ring and prove the effectiveness of the dominant external excitation frequency identification method and vibration absorber control strategy.

Stator Faults Detection on Induction Motors Using Harmonic Sequence Current Components Analysis

In this paper we propose a strategy for detecting interturn short circuits on stator windings of three-phase induction motors (IM). The strategy is based on an analytical model that includes a stator fault in any of the phase windings considering the h-th harmonic in the supply voltage. To find the adequate model, we propose an equivalent electrical circuit of the IM in steady state, considering each sequence component. The proposed strategy allows the detection of an interturn short-circuit fault by monitoring the fifth-order harmonic component. We present simulation and experimental results for the faulty IM and different operating conditions. In the laboratory tests, we use a programmable power supply in order to synthesize distorted and unbalance voltages. Also, the windings of a three-phase IM have been modified to generate stator faults and validate the proposed model. The results show that the sustained increase of the fifth-order harmonic of positive-sequence current is a good indicator of the fault severity.

Emulation of battery discharge behaviour using programmable power supply based on LabVIEW

This paper presents a battery simulator based on the actual electrical behaviour of the battery cells using power supply controlled by Laboratory Virtual Instrument Engineering Workbench (LabVIEW). Firstly, the behaviours of the battery are tested under experimental conditions including constant temperatures at 25C˚ and two different current loads at 0.5C and 1C. Secondly, the battery behaviours are analysed and applied in LabVIEW. The algorithms which are low pass filter, PID and others are implemented in LabVIEW to reduce standard deviations and errors. The current study found that the constant load at 0.5C and 1C, which controlled by the electronic load via LabVIEW, can emulate the battery voltage and the error relative is below 5 %. Further work is required to establish the optimization of the parameters in the battery management system (BMS) since a battery simulator uses power sources before the use of the battery management system (BMS) with a real battery.

Development of Arc Welding Technology with Support of Stability of Electrode Melting Process

Mechanized arc welding is divided into two main varieties: with self-regulation of the electrode melting process and with automatic process control. The common thing between self-regulating mechanized arc welding and manual arc welding is that in the welding equipment there are no means for automatic control with feedback from the arc. The difference between them is that stabilization of the electrode melting process in mechanized welding is carried out by the source itself, which has a particular volt-ampere characteristic (CVC), by a corresponding spontaneous reaction to a change in the situation in the arc. This method is significantly inferior to the method with automatic process control in precisely maintaining the specified parameters and has a limitation on the minimum current density on the electrode. The method of pulse self-regulation of the electrode melting process proposed in the E.O.Paton EWI removes this problem. However, it requires the use of power sources with a complicated, multi-link CVC curve. Further improvement is revealed through the use of digital controlled, programmable power supplies that have an automatically generated CVC. The combination of automatic source control and self-regulation by the spontaneous reaction to the situation in the arc creates a new hybrid way to stabilize the process of arc welding with a consumable electrode and other related arc processes (surfacing, soldering, re-melting).

Energy flow control of electric vehicle based on GNSS

In this paper, a system for controlling the energy flow of vehicle with multiple energy storages which are used for increasing performance and driving range is presented. For achieving maximal performance and efficiency of energy flow control, traction profile of the route is necessarily known. For observation of a traction profile, Global Navigation Satellite System is used. For energy flow control, three algorithms are presented. The first proposed algorithm uses the whole traction profile of a predetermined route by the driver so the control algorithm can decide the energy of the second energy storage efficient. The second algorithm eliminates the biggest disadvantage of predetermining route, so the algorithm uses traction profile from the memory of stored routes where the vehicle was already driven. If the route was not defined or found in memory energy of secondary energy storage, (supercapacitor) using will be based on the current of primary energy storage (batteries). For verification of proposal algorithms for control of DC/DC converter which is used for energy flow control, inverter and motor were simulated with programmable load and programmable power supply.

Application of a precision programmable DC power supply for spectrometer calibration

The paper presents the circuitry solutions on the basis of which a precision programmable DC power supply was created and tested. The principle of operation of the DC power supply uses a high-precision method of controlling a pulse current stabilizer, based on the adaptation of the duty cycle of the pulse-width modulation (PWM) signal to control the inverter when the load mode changes. From the output of the inverter, the signal is converted by the rectifier into a DC signal with subsequent smoothing of the ripple and enters the load circuit. From a precision low-resistance shunt connected to the load circuit, the signal through the ADC in digital form enters the control unit (CU), implemented on the basis of FPGA, which has a embedded programme for controlling the voltage / current stabilization modes in the load circuit. In addition, the paper shows the use of a precision programmable DC power supply for solving the problem of calibrating the BTC-110S spectrometer. The block diagram of the test stand for spectrometer calibration is presented and relations for the correction of the recorded signals of the thermal radiation spectrum of the objects under study are derived.

An Efficient and Robust Current Control for Polymer Electrolyte Membrane Fuel Cell Power System

Taking into account the restricted ability of polymer electrolyte membrane fuel cell (PEMFC) to generate energy, it is compulsory to present techniques, in which an efficient operating power can be achieved. In many applications, the PEMFC is usually coupled with a high step-up DC-DC power converter which not only provides efficient power conversion, but also offers highly regulated output voltage. Due to the no-linearity of the PEMFC power systems, the application of conventional linear controllers such as proportional-integral (PI) did not succeed to drive the system to operate precisely in an adequate power point. Therefore, this paper proposes a robust non-linear integral fast terminal sliding mode control (IFTSMC) aiming to improve the power quality generated by the PEMFC; besides, a digital filter is designed and implemented to smooth the signals from the chattering effect of the IFTSMC. The stability proof of the IFTSMC is demonstrated via Lyapunov analysis. The proposed control scheme is designed for an experimental closed-loop system which consisted of a Heliocentric hy-Expert™ FC-50W, MicroLabBox dSPACE DS1202, step-up DC-DC power converter and programmable DC power supplies. Comparative results with the PI controller indicate that a reduction of 96% in the response time could be achieved using the suggested algorithm; where, up to more than 91% of the chattering phenomenon could be eliminated via the application of the digital filter.

The Impact of Supply Voltage Waveform Distortion on Non-Intentional Emission in the Frequency Range 2–150 kHz: An Experimental Study with Power-Line Communication and Selected End-User Equipment

Knowledge of the conducted emissions in the frequency range 2–150 kHz contains some gaps related to the impact of the harmonics in the supply voltage on the nature of these emissions. It can be noticed that the conducted emissions from non-sinusoidal power supplies have not been studied sufficiently, and that the impact of this distortion may be greater than the generally known results of emission tests carried out under standardized test conditions. This paper is aimed at investigating experimental cases of the influence of supply voltage waveform distortion on non-intentional emission in the range 2–150 kHz and the efficiency of power line communication based on selected PRIME (PoweRline Intelligent Metering Evolution) power line communication (PLC) technology. A series of experimental laboratory studies were investigated, representing the operation of the investigated PLC system with different types of end-user equipment (LED—Light Emitting Diode, CFL—Compact Fluorescent Lamp, induction motor with frequency converter) working under a distorted supply voltage condition obtained by the programmable power supply for different scenarios of the admissible harmonics contribution in the range 0–2 kHz. The scenarios included limits defined in standards EN 50160 and IEC 61000-4-13. The researchers used spectral analysis with a notation to emission limits, compatibility levels, and mains signalling, as well as statistics of the PLC communication. The obtained results provide important conclusions, which may be applied both in the development of the design of the appliances in question and the higher frequency emission testing methods.

Highly Integrated ZVS Flyback Converter ICs With Pulse Transformer to Optimize USB Power Delivery for Fast-Charging Mobile Devices

Flyback converter with USB power delivery is widely used for fast-charging mobile devices. However, conventional solutions have issues such as lower efficiency, higher cost, a large number of external components, and lower loop gain bandwidth. In this article, a high-efficiency zero-voltage switching (ZVS) flyback converter with primary- and secondary-side control ICs is proposed to solve the aforementioned issues with high integration level. The proposed control replaces optocoupler to achieve ZVS and secondary-side-regulation (SSR) by a pulse transformer. The ICs further integrate the USB power delivery (PD) controller and the constant voltage (CV)/constant current (CC) loop compensation to reduce external components. The proposed control and small-signal model are illustrated and verified by the experiment. The control ICs were fabricated in a 180-nm BCD process. The implemented 20-V/3-A/60-W USB PD flyback converter achieved 93.5% maximum efficiency using Si power switches. The feasibility of the proposed converter is verified by a thorough test of programmable power supply (PPS) with various CC/CV levels and load/line transients.

Color‐Tunable 3D InGaN/GaN Multi‐Quantum‐Well Light‐Emitting‐Diode Based on Microfacet Emission and Programmable Driving Power Supply

AbstractColor‐tunable InGaN/GaN multi‐quantum‐well (MQW) light‐emitting diodes (LEDs) are reported based on GaN microfacet structure directly grown on c‐plane patterned sapphire substrate by metal organic vapor phase epitaxy (MOVPE) through promoting 3D growth. By adjusting GaN growth temperature and pattern arrangement, a GaN microfacet with almost pure {101} semipolar facets is obtained. The multifacetted InGaN/GaN MQW LED chip evolves three distinct emission peaks around 630, 530, and 450 nm in electroluminescence (EL) as injection current increases from 1 to 100 mA. The EL behavior originates from locally different facets of the complex 3D structure: MQWs grown on c‐planes and semipolar facets, respectively, which is confirmed by cathodoluminescence characterization in a scanning transmission electron microscope (STEM‐CL). Considering the dependence of emission wavelength and intensity on injection currents, a programmable power supply is designed to drive the LED. The specific color of the LED is tuned by time‐shared driving of the currents based on three channels with controllable magnitudes and duty cycle from the power supply, covering red, yellow, green, cyan, blue, and purple. Furthermore, white LEDs with high color rendering index (CRI) up to 96.1 and correlated color temperature (CCT) between 4000 and 10 000 K are achieved.

Optimized Control of Energy Flow in an Electric Vehicle based on GPS

Presented paper deals with energy flow control of an electric vehicle with multiple energy storages. For efficiency control of energy flow is necessary to know the traction profile of the route. The Global Positioning System is used for observation of the traction profile. The first of the proposed algorithms uses the whole traction profile of a predetermined route, so the control algorithm can determine when the use of energy of the secondary energy storage is useful. The second proposed algorithm uses the GPS to determine the traction profile from routes stored in memory. If the route is not predetermined, or found in the memory of stored routes, the last algorithm controls the energy flow, based on the current of the primary energy storage. For verification of the proposed algorithm for control of the DC/DC converter, motor with inverter was replaced by the programmable power supply and programmable electronic load. The final evaluation shows that the proposed algorithm with the predetermined route saves about 5% more energy than the basic algorithm based on the battery current.

Research on Non - contact Electromagnetic Loading Device for Water - lubricated Bearing

In order to deeply study the characteristics of water-lubricated bearing under load condition, a non-contact electromagnetic loading device is designed to solve the problems of friction, vibration and noise in the traditional contact loading methods such as hydraulic cylinder and weight, etc. The device consists of loading plate, E magnets, coil, programmable dc power supply, first of all, is derived by Maxwell’s three laws of the theoretical equation of electromagnetic force, and then, application of Solidworks, Ansoft Maxwell 18.2 software modeling and simulation of electromagnetic loading device structure, the final will be the electromagnetic simulation, comparing the theoretical results, the results show that the simulation and the theoretical value is less than 11.4%, validate the rationality and accuracy of the device.

Simultaneous feedback control of toroidal magnetic field and plasma current on MST using advanced programmable power supplies

Programmable control of the inductive electric field enables advanced operations of reversed-field pinch (RFP) plasmas in the Madison Symmetric Torus (MST) device and further develops the technical basis for ohmically heated fusion RFP plasmas. MST’s poloidal and toroidal magnetic fields (B p and B t) can be sourced by programmable power supplies (PPSs) based on integrated-gate bipolar transistors (IGBT). In order to provide real-time simultaneous control of both B p and B t circuits, a time-independent integrated model is developed. The actuators considered for the control are the B p and B t primary currents produced by the PPSs. The control system goal will be tracking two particular demand quantities that can be measured at the plasma surface (r = a): the plasma current, I p ∼ B p(a), and the RFP reversal parameter, F ∼ B t(a)/Φ, where Φ is the toroidal flux in the plasma. The edge safety factor, q(a) ∝ B t (a), tends to track F but not identically. To understand the responses of I p and F to the actuators and to enable systematic design of control algorithms, dedicated experiments are run in which the actuators are modulated, and a linearized dynamic data-driven model is generated using a system identification method. We perform a series of initial real-time experiments to test the designed feedback controllers and validate the derived model predictions. The feedback controllers show systematic improvements over simpler feedforward controllers.

Modeling and Motion Control of a Liquid Metal Droplet in a Fluidic Channel

As an emerging multifunctional material, Gallium-based room temperature liquid metal has attracted a lot of attention for a variety of applications due to its mobility and deformability. However, controlling the motion of a liquid metal droplet accurately still remains unrevealed, which restricts its application in many fields. In this article, we propose a hybrid framework that would control the motion of a liquid metal droplet in a one-dimensional (1-D) fluidic channel. A dynamic model of a liquid metal droplet immersed in the electrolyte when an electrical field is applied to each end of the channel is discussed first, followed by a setpoint controller designed to calculate the current input needed to drive the liquid metal droplet to its destination with vision feedback. To obtain the desired high-resolution current output, a fast and high-resolution current output power supply will be established by integrating a fast PID controller and a simple programmable dc power supply. The effectiveness of this proposed approach will be verified by controlling a liquid metal droplet so that it reaches its destination inside the polymethyl methacrylate channel. In this article, the proposed approach may lead to the development of tiny soft robots, or microfluidic systems that can be driven accurately by the liquid metal droplets.

Time-Dependent Demagnetization of NdFeB Magnets Under DC and Pulsed Magnetic Fields

This article investigates the time-dependent demagnetization behavior of NdFeB permanent magnets used for electrified vehicles. A mathematical model of magnetic viscosity was derived using maximum-likelihood estimation based on the test data. This magnetic viscosity model was then used to predict the magnet demagnetization behavior over time. A demagnetization test fixture and a programmable dc power supply were used to apply a constant demagnetizing field to N48H magnet samples. A hall-effect sensor was used for online measurement of the magnetic field under a constant demagnetizing field over a wide time range. A buck converter was used to generate a pulsed demagnetizing field in the timescale of milliseconds. The results of this article will help understand the demagnetization behavior of NdFeB magnets caused by overcurrent faults in permanent-magnet synchronous machines.

Real-time emulation of photovoltaic energy using adaptive state feedback control

The current paper presents an experimental validation of photovoltaic (PV) source emulation using a real-time dSpace controller. The PV source emulator is a nonlinear power electronic device used to provide in real-time the electrical behavior of PV panels by tracking the PV current–voltage (I–V) characteristic. It aims to deliver nearly the same current and voltage as an actual PV module without depending on atmospheric conditions. This innovative tool is able to aid researchers in PV systems to perform their tests and measurements at the desired weather parameters without time, space and cost constraints. The proposed PV emulator is based on a simple and efficient adaptive state feedback control that ensures good accuracy and high dynamic response compared to the existing commercial PV emulators based on the programmable power supply, which improves significantly the static and dynamic performances of existing PV emulators.