Constant Current Power Supply Research Articles

Low-cost bidirectional coil driver with microamp precision

We describe a compact constant current power supply with µA precision designed to drive coils. The unit generates currents from −125 mA to 125 mA with a load up to 10 Ω using a precision 16-bit digital to analogue converter, driven from a microcontroller (e.g. Raspberry Pi Pico). All power for the unit is derived from the 5 V of the microcontroller. As a demonstration of the capability of the power supply, it was applied to spin manipulation in a helium spin echo system.

Voltage Equalizing Strategy for Cascaded Constant Current Power Supply

In order to detect the underground medium with large depth, the transmitter of electromagnetic sounding instrument has higher and higher power and voltage. A novel voltage equalizing strategy for cascaded constant current power supply using in electromagnetic transmitter was proposed in this paper. The cascaded topology of the transmitter has two isolated full‐bridge AC/DC converters, which had same input source and were connected in series on the output side. The mathematical model based on state space average method was analyzed. After simplifying the circuit, the state space equation was used to describe the circuit model. The stability and frequency characteristics of the system were analyzed. Aiming at the constant current output and the output voltage balance of the two converters, the system coupling model was established. The constant current controller and voltage equalizing controller were designed with decoupling method. A 300 W prototype was built and the experimental results verified the performance of the proposed method. © 2024 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC.

Constant current pulsed power supply for long pulse arc discharge positive hydrogen ion source.

The simplest way to produce high density hydrogen plasmas is to form an arc between the arcing electrode and the plasma chamber (cathode). For arc-based hydrogen plasma generation, a pulsed power supply that delivers 2 ms-long constant current pulse has been developed. This pulsed power supply employs a high frequency buck converter topology with a nonlinear filter inductor. This paper describes the development and testing of a constant current pulsed power supply that operates at 50A and 550V with a pulse width of 2ms and a pulse repetition rate of 2Hz. By changing the arc current, the arc impedance and the positive hydrogen ion current were also measured. The extraction of positive hydrogen ions was carried out using a three-electrode extraction design, which results in a current of 80 mA of positive hydrogen ions at an energy of 50keV.

A constrained engineering design method for constant-current remote power supply system of mesh-type cabled underwater information networks

Remote power supply technology is critical for the long-term, wide-area, and real-time monitoring of marine data in cabled underwater information networks (CUINs). In this study, the constant-current remote power supply system (CCRPSS) of mesh-type CUINs based on constant-current branch equipment (CCBE) and constant-current/constant-voltage conversion equipment (CCVE) is studied. The system can be categorized into various power supply links and link segments according to the current flow path and structural characteristics. A system basic simulation model is designed to analyze the influence of 11 typical faults on the working state of the system and to summarize the influence of the open-circuit/short-circuit faults of various underwater units in different power supply link segments on the working state of the system. Then the analysis method of power supply reliability (PSR) of the observation equipment (OE) is proposed. The PSR of the OE of the same power supply link (PSL) decreases gradually from shore to sea, and the PSR of the OE located at the center of the PSL is the lowest in the regular deployment of the CCRPSS. To increase the number of nodes deployed and to reduce the total cost, an engineering design method for the system that integrates the constraints of the PSR of the OE, the fault rate of the underwater unit, and the number of second nodes of each power supply link segment (PSLS) is proposed based on invasive weed optimization (IWO). Through the example simulation, the results of the system cost, the deployment number of secondary nodes, and the reliability of the underwater units are obtained, which also confirms that the PSR of the OE located at the center of the PSL is the lowest. This method can be effectively applied to the engineering design of CCRPSS and can provide theoretical and technical support for future large-scale CUINs construction.

Analysis and Design of Two-Stage Cascaded LED Load Wireless Power Transfer System

This paper proposes a two-stage cascaded wireless power transfer (WPT) system aimed at increasing the transfer radius and supplying power to multiple low-power loads. The proposed WPT scheme is regarded as a cascading of two WPT systems. The system realizes constant current power supply for two-stage LED load and put emphasis on solving the problems of limited power supply radius and power supply of multiple constant current/voltage loads in WPT system. Four basic power supply types of transmission network are discussed in this paper, and the compensation network structures and parameters suiting for these types are determined by analyzing every stage’s input and output characteristic using two-port network T matrix. The result of research validates that constant current is achieved in general. Moreover, the two stage’s maximum efficiency is 68.04% when the LED total number changes from 6 to 13, which proves the feasibility of the proposed scheme.

Non-traditional power supply mode: Investigation of electrodeposition towards a better understanding of PbO2 electrode for electrochemical wastewater treatment

The power supply mode is a non-negligible character in electrochemical process. Constant current mode is used in the traditional electrodeposition preparation process of PbO2 electrode, and there are very few studies on its electrodeposition power supply mode. In this paper, two non-traditional power supply modes (linear increase power supply mode and linear decrease power supply mode) were used to fabricate PbO2 electrodes, and the properties of prepared electrodes were compared with those of the traditional constant current power supply mode. On the premise of improving the electrode properties, the non-traditional power supply mode also significantly reduced the energy consumption of the electrodeposition process of PbO2. After material characterization (Scanning electron microscope, X-ray diffraction), electrochemical characterization (Electrochemical impedance spectroscopy, linear sweep voltammetry etc.) and stability test, it can be seen that the electrode surface prepared by the non-traditional power supply mode was spherical particles and its average grain size was smaller than that of the traditional one. The PbO2 electrode prepared by linear increase power supply mode had higher oxygen evolution overpotential (1.962 V), more active sites, smaller membrane impedance (33.15 Ω) and better stability (accelerated life up to 125.1 h). In the electrocatalytic oxidation tests of the three electrodes, the PbO2 electrode prepared by linear increase mode had the best performance in decolorization rate, Chemical oxygen demand removal rate, average current efficiency and energy consumption. Owing to favorable effects obtained, non-traditional power supply mode could be considered a promising alternative for PbO2 electrode preparation and applied electrochemical process for wastewater treatment.

A Repetitive Low Impedance High Power Microwave Driver

A low impedance high power microwave (HPM) driver is designed, which can be used in studying multi-gigawatt HPM devices such as the magnetically insulated transmission line oscillator (MILO), based on a helical pulse forming line (PFL) and the Tesla pulse transformer technology. The co-axial PFL is insulated by ethanol–water mixture, whose dielectric constant can be adjusted; and the helical line increases the output pulse width as well as the impedance to make a better match with the load. By the optimal combination of PFL charging voltage and output switch working voltage, the reliability of the PFL can be improved. The Tesla transformer has partial magnetic cores to increase the coupling coefficient and is connected like an autotransformer to increase the voltage step-up ratio. The primary capacitor of the transformer is charged by a high voltage constant current power supply and discharged by a triggered switch. A transmission line is installed between the PFL and the HPM load, to further increase the load voltage. A ceramic disk vacuum interface is used for improving the vacuum of the HPM tube. The experiments show that the driver can operate at 30 GW peak power, 75 ns pulse width and 5 Hz repetition rate.

Estimate the Meaning-Time-To-Failure of LED driver using Numerical simulation

The Meaning-Time-To-Failure (MTTP), also known as Electromigration Analysis is an estimation of product life. Light-Emitting Diodes (LEDs) are usually driven by constant current switched-mode power supplies, which are invented early than LEDs for lighting applications. While LEDs themselves are extremely reliable and have a long lifetime, the electronic LED drivers in experiment usually fail due to overheating causing Printed Circuit Boards (PCBs) explosion, inability provide current/voltage input to the LEDs over their whole lifetime. This paper proposes a numerical simulation method to predict fault location on PCB of LED driver based on 2-way coupling electro-thermal multiphysic analysis, then applies the analytic models to calculate the time to failure of the points on PCB of LED drivers. The procedures can be applied to assist managers in assessing risk and making LED-based lighting system reliability decisions.

Fault diagnosis of the constant current remote power supply system in CUINs based on the improved water cycle algorithm

Cabled Underwater Information Networks (CUINs) is an important platform for ocean observation where the Constant Current Remote Power Supply System (CCRPSS) guarantees the safe and normal operation of CUINs. The CCRPSS is mainly composed of the main node and underwater cables which require frequent fault diagnosis but how to improve the fault diagnosis rate is a difficult problem. This paper proposed a fault diagnosis method for the CCRPSS based on the Improved Water Cycle Algorithm (IWCA) and the multi-classifier group based on the Least Squares Support Vector Machine (LSSVM). Firstly, the multi-feature extraction method is used to obtain the characteristic information in the time and frequency domain; secondly, IWCA is established by combining the traditional Water Cycle Algorithm (WCA) with the chaotic mutation strategy, the elite memory strategy and the population reconstruction strategy. By applying 13 typical test functions to performance test, it can be found that the IWCA can effectively improve the global search ability and balance of the WCA algorithm. At last, IWCA is used to optimize the parameters of the LSSVM classifier and improve the classification efficiency. The comparisons of simulated results with traditional methods show that the proposed diagnostic model can not only obtain complete fault feature information, but also obtain the optimal classification parameters of LSSVM faster. Therefore, the proposed diagnostic method is verified to be suitable for the fault diagnosis of the constant current remote power supply system in CUINs.

Improvement of electromagnetic compatibility and efficiency of power supply circuits of electric arc furnaces in nonlinear asymmetric modes

AC steel arc furnaces are the most powerful units connected to the electrical grid, the operating mode of which is dynamic, asymmetrical and non-linear. That is why these furnaces cause the entire possible range of negative effects on the quality of electricity in the grid, in particular, fluctuations, asymmetry and non-sinusoidal voltage.Known proposals for improving the electromagnetic compatibility of electric arc furnaces are mainly focused on eliminating the consequences of their ne­gative impact on the power grid.The proposed approach and the corresponding technical solution are aimed at reducing the level of generation of a negative factor and at the same time reduce fluctuations, asymmetry and non-sinusoidal voltage. This result is obtained due to the fact that the proposed solution takes into account the peculiari­ties of the range of modes natural for arc furnaces. Optimal for such consumers is the use of a constant current power supply system I=const in the range of modes from operational short circuit to maximum load and the system U=const in the whole other range of modes. The implementation of such a system is carried out on the basis of a resonant converter «constant current – constant voltage».Studies have found that the use of such a power supply system, in comparison with the traditional circuit, makes it possible to reduce the non-sinusoidal voltage in a low-power grid from 3.2 % to 2.1 % and the unbalance coefficient from 3.66 to 1.35 %. Previously published data on a significant reduction in voltage fluctuations was also confirmed.The positive effect of such a system on the energy performance of the furnace itself is shown, manifes­ted in an increase in the arc power by 12.5 %, and the electrical efficiency by 5.1 %. This improves the productivity and efficiency of electric arc furnaces

Effect of Flow Rate on the Characteristics of Atmospheric-Pressure AC Constant-Current Powered Gliding Arc Discharge

In this article, a nonthermal gliding arc discharge (GAD) was generated in an air flow driven by a 40-kHz alternating current (ac) constant-current electric power supply. The influence of gas flow rate on the discharge characteristics of gliding arc was investigated using electrical diagnostics and fast Fourier transform (FFT) analysis method. The average discharge power, total harmonic distortion rate of arc voltage (THD <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${_{u}}$ </tex-math></inline-formula> ), total harmonic distortion rate of arc current (THD <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${_{i}}$ </tex-math></inline-formula> ), and the resistance of arc were experimentally studied. As the air flow rate increased from 4 to 12 L/min, it was found that the average discharge power of the gliding arc gradually decreased from 407.9 to 187.8 W. However, because of the nonlinear characteristics of the GAD circuit, with air flow rate increasing, both THD <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><i>u</i></sub> and THD <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><i>i</i></sub> linearly increased, while the resistance of arc gradually decreased from 26.3 to 14.1 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{k}\Omega $ </tex-math></inline-formula> . Totally, the air flow rate influenced the discharge characteristics of the gliding arc mainly by ruling the average discharge power. Finally, for a better understanding of the discharge characteristics of the gliding arc, a discharge circuit model was further analyzed based on the average discharge power and reactive power.

Fuzzy self-tuning PID control of MC3 LLC resonant LED drivers

An MC3 LLC resonant light-emitting diode (LED) driver is a multi-channel constant current (MC3) output solution based on LLC resonance. Through an effective combination of multiple transformers and a DC block capacitor, this driver allows constant current outputs in multiple channels when the LED channels are unbalanced. This study considers a fuzzy self-tuning proportional integral derivative (PID) control strategy that allows for the self-tuning of PID parameters according to fuzzy inference rules designed using the relationship between the current gain and the switching frequency. Thus, when LED channels are unbalanced, the system allows a constant current output for each of the channels and controls the input voltage disturbances well. Simulation and experimental verifications are carried out, and a 20 W 4-channel constant current power supply design based on LLC resonance is obtained for the LED driver. This realizes soft-switching of the switching device, which reduces system loss and improves system efficiency. Moreover, the adjustment time of the proposed method is half that of fixed-parameter control methods, and the overshoot of the proposed method is smaller than that of fixed-parameter control methods. When compared with PID controllers with fixed parameters, the proposed method is more robust. When a system is disturbed, it recovers faster and has a smaller range of current fluctuation with the proposed method.

Diseño e implementación de un controlador de 6 grados de libertad, para el sistema GRACE.

En este artículo el lector podrá obtener información sobre el escáner 3D de la Universidadde Groningen. El proceso de diseño incluyendo el control para el sistema con 6 grados delibertad, así como la luz que es regulada para tener datos limpios utilizando un algoritmo y unafuente de corriente constante es mostrado en el documento. La implementación y resultadosson mostrados, así entonces el lector puede analizar los materiales y métodos para futurasaplicaciones

Development of compact rapid capacitor charging power supply for TMS

To improve the stimulation efficiency of transcranial magnetic stimulation (TMS) and reduce the size and power consumption of the overall circuit, a compact and efficient capacitor charging power supply using an inductor–capacitor–inductor–capacitor resonant converter (LC–LC RC) is designed in this study. The LC–LC RC has the characteristics of low power consumption, high efficiency and uses the voltage gain of the resonant circuit itself and a voltage doubler rectifier circuit instead of the transformer to reduce the size and weight of the overall circuit. A detailed ac analysis with fundamental frequency approximation of the LC–LC RC is presented. Expressions for converter gain, operating condition of the converter as a constant-current power supply, and condition of the converter voltage and current zero-phase difference are derived. In addition, RC design value conditions for the minimum resonant network size are derived. An experimental 1.05 A 120 V prototype converter is designed, developed, and tested to verify the theoretical analysis. Experimental results indicate that this circuit is suitable for use in capacitor charging to increase the stimulation performance of TMS.

A new approach for analyzing the effect of non-ideal power supply on a constant current underwater cabled system

The effect of a constant current (CC) power supply on the CC ocean observation system is a problem that once was neglected. The dynamic characteristics of the CC power supply may have great influence on the whole system, especially the voltage behavior in the event of load change. This needs to be examined. In this paper, a method is introduced to check whether the CC power supply can satisfy the dynamic requirements of the CC ocean observation system. An equivalent model to describe the non-ideal CC power supply is presented, through which the dynamic characteristics can be standardized. To verify the feasibility of this model, a minimum system of a single node in the CC ocean observation system is constructed, from which the model is derived. Focusing on the power failure problem, the output voltage responses are performed and the models are validated. Through the model, the dynamic behavior of the CC power supply is checked in a practical design.

Pulsed electrochemical oxidation of acid Red G and crystal violet by PbO2 anode

Present work investigates the application of pulsed electrochemical oxidation technique using DSA anode, titanium coated with PbO2layer, for degradation of Acid Red G (anionic dye) and Crystal Violet (cationic dye). Decolorization efficiency, COD and TOC removal efficiency were measured and contrasted by varying process parameters such as current density, initial organic concentration, pulse frequency, pulse duty cycle and NaCl dosage. Furthermore, decay kinetics for color and COD removal process, average current efficiency and energy consumption were evaluated under diverse arguments. The results indicated that current density, pulse duty cycle and NaCl dosage exerted a positive influence on the performance of pulse electrochemical degradation for ARG and CV, namely, with the growth of relevant influencing factors, the corresponding removal efficiency, kinetic constant of decolorization and COD removal reaction, and specific energy consumption increased accordingly, whereas the average current efficiency gradually decreased. However, the initial concentration of ARG and CV had a negative influence on the pulse electrochemical degradation process, that is, with the increase of initial dye concentration could lead to the reduction of the corresponding removal efficiency, kinetic constant of decolorization and COD removal reaction and energy consumption, on the contrary, the average current efficiency went up. Being different from ARG degradation process, there were some substances adhering to the cathode during CV electrochemical degradation process due to its positive charge. Under same conditions, the degradation indexes of pulse constant current power supply mode were better than those of direct constant current mode, which was coincident for both ARG and CV.

Design of automatic measurement system for pre-tightening parameters of multi-axis wrist force pressure sensor

Aiming at the shortcomings of low efficiency and poor accuracy of the existing pressure sensor pre-tightening parameter measurement system, an automatic multi-axis wrist force sensor pre-tightening parameter measurement system is designed. The multi-axis wrist force sensor module is used to collect real-time tension signal from the loaded hand wheel. After amplification, the signal is transmitted to the multi-channel gating module through RS485 communication module to realize the tested sensing. After fast switching and constant current source power supply control function, the data collector collects the pull signal obtained by multi-axis wrist force pressure sensor and transmits it to the upper computer of the system designed by LabVIEW through RS485 bus. The upper computer controls and collects the pressure sensor according to the pull signal feedback from the data collector, and the pre-tightening displacement of multi-axis wrist force sensor is determined by parameters such as axial displacement and friction resistance moment. The experimental results show that the designed system can fully measure the pre-tightening parameters of the sensor, and the starting moment measurement error is only 0.102%. The system can meet the requirements of batch measurement and calibration of multi-axis wrist force sensor with accuracy of 1%-0.1%.

Design and Analysis of an Equivalent Load Power-Stability Control Circuit for Cabled Underwater Information Networks

Cabled underwater information networks (CUINs) have evolved over the last decade to provide abundant power and broad bandwidth communication to enable marine science. To ensure reliable operation of the CUINs, the stability of the remote power supply system, a key component of underwater power facilities, is essential. To avoid instability and collapse of the power system caused by rapid changes in load, we propose an equivalent load power-stability control circuit suited for an underwater constant current power supply system. This circuit can change its own working state according to the size of the load and play a role in power compensation. In order to prove the feasibility of the converter design, the working state of the circuit under different load values was analyzed and the performance of circuit was verified through simulation and experiments. The results show that when the load resistance changes within a large range (including when the load has an open circuit or short circuit fault), the equivalent load is basically unchanged or changed within a very small range for the constant current source, causing the constant current source to maintain stable output voltage and output power. Thus, the influence of the branch line cable on the trunk line cable is reduced, and the reliability of the underwater constant current power supply system is improved. Furthermore, the equivalent load power-stability control circuit would facilitate live equipment replacement and maintenance for CUINs.

Research and Design of Marine Underwater LED Illumination System Based on Sliding Mode Variable Structure

Pan, P., 2019. Research and design of marine underwater LED illumination system based on sliding mode variable structure. In: Li, L.; Wan, X., and Huang, X. (eds.), Recent Developments in Practices and Research on Coastal Regions: Transportation, Environment and Economy. Journal of Coastal Research, Special Issue No. 98, pp. 239–242. Coconut Creek (Florida), ISSN 0749-0208.This paper introduces the working characteristics of an underwater LED illumination system and analyzes the driving power supply of the LED illumination system and the application of its control mode. In addition, the sliding mode variable structure control (SMVSC) method of constant-current power supply for an underwater LED illumination system is studied and designed in this paper. By choosing appropriate sliding mode surface function and control parameters, the constant-current control of the LED load is realized. Finally, to verify the effectiveness and superiority of the SMVSC method design for the LED illumination system, the SMVSC method is modeled and simulated using MATLAB software and compared with the conventional PI control method, which proves the validity of the design.

A study on the 3D fluid flow of MHD micropump

In this paper, a 3D model of magnetohydrodynamic (MHD) micropump with a rectangular channel was modeled and numerically simulated based on the finite volume method. Effects of geometrical parameters such as depth, width, and length of the side electrodes were studied on the maximum flow rate, maximum pressure, and energy rate of the rectangular MHD channels in constant electric current and constant power supply modes. The multiple attributes decision-making method was used in order to identify the most effective geometrical parameters on the performance of the micropump. Wider channels with long electrodes are identified to be in favor of high performance for high flow rate, high pressure, and energy-efficient demands. A case study of new profile with a widened channel in the pumping section was proposed, and its new geometrical parameters are introduced. Studies at constant energy rate of 1 mW showed that the extension of the channel width (electrode walls) can increase the flow rate up to 1.23 μl/min (34% increase in comparison with non-extended channel). Additionally, it was found that when the extension parameter is set to 3.5 (D/w = 3.5), the flow rate is independent of the elongation parameter (r/R).