More Like this

1. An efficient DC‐DC converter for inductive power transfer in low‐power sensor applications

   https://doi.org/10.1002/cta.3285  

   Lu, Ruikuan ; Hossain, Md. Kamal ; Alexander, J. Iwan ; Massoud, Yehia ; Haider, Mohammad R. ( April 2022 , International Journal of Circuit Theory and Applications)

   Inductive power transfer has become an emerging technology for its significant benefits in many applications, including mobile phones, laptops, electric vehicles, implanted bio‐sensors, and internet of things (IoT) devices. In modern applications, a direct current–direct current (DC–DC) converter is one of the essential components to regulate the output supply voltage for achieving the desired characteristics, that is, steady voltage with lower peak ripples. This paper presents a switched‐capacitor (SC) DC–DC converter using complementary architecture to provide a regulated DC voltage with an increased dynamic response. The proposed topology enhances the converter efficiency by decreasing the equivalent output resistance to half by connecting two symmetric SC single ladder converters. The proposed converter is designed using the standard 130‐nm BiCMOS process. The results show that the proposed architecture produces 327‐mV DC output with a rise time of 60.1 ns and consumes 3.449‐nW power for 1.0‐V DC supply. The output settling time is 43.6% lower than the single‐stage SC DC–DC converter with an input frequency of 200 MHz. The comparison results show that the proposed converter has a higher power conversion efficiency of 93.87%and a lower power density of 0.57 mW/mm²compared to the existing works.

    

   more » « less
2. A 120V-to-1.8V 91.5%-Efficient 36-W Dual-Inductor Hybrid Converter with Natural Soft-charging Operations for Direct Extreme Conversion Ratios

   https://doi.org/10.1109/ECCE.2018.8557854  

   Das, Ratul ; Seo, Gab-Su ; Le, Hanh-Phuc ( September 2018 , 2018 IEEE Energy Conversion Congress and Exposition (ECCE))

   This paper presents a new dual inductor hybrid converter (DIHC) that is capable of efficient direct non-isolated DC-DC conversions with extremely large voltage conversion ratios. The converter employs two interleaved inductors and a switched-capacitor (SC) network to bring several significant topological benefits. Capacitance of the flying capacitors of this new topology can be optimally sized to achieve natural, complete soft-charging for all capacitors. This novel capacitor soft-charging feature is a key contribution of this work and can be exploited to overcome the limitations of conventional SC converters suffering from capacitor hard charging losses. The converter topology and its operation are verified in an 36-W converter prototype for 40-120V input to 0.9V-1.8V output up to 20A of current load that achieves peak efficiencies of 91.5% for 120V-to-1.8V and 87.3% for 120V-to-0.9V conversion. Its advantages and performance at extreme conversion ratios push the limit of point-of-load converters, reducing complexity and cost for bus voltage distributions, as well as enabling fewer conversion stages and thus higher efficiency for data centers and high-performance digital systems. 

   more » « less
3. A New High Step-Up DC-DC Topology with Zero DC Magnetizing Inductance Current and Continuous Input Current

   https://doi.org/10.1109/APEC39645.2020.9124151  

   Mahmoudi, Mohsen ; Ajami, Ali ; Babaei, Ebrahim ; Abdolmaleki, Nima ; Wang, Caisheng ( March 2020 , 2020 IEEE Applied Power Electronics Conference and Exposition (APEC))

   null (Ed.)

   A new high-voltage-gain non-isolated dc-dc topology for applications in renewable energies is proposed. A coupled inductor with three windings is used to increase the proposed topology voltage gain. In addition to increasing the voltage gain, the proposed topology also has other prominent features including continuous input current and zero dc magnetizing inductance current, which reduces the losses and size of coupled inductor core. Furthermore, the continuous input current guarantees a low-volume input filter, which is essential for renewable energy applications. The leakage inductor stored energy is recycled via the diode and capacitor and transferred to the converter output for increasing the efficiency and reducing voltage stresses on the converter components. 

   more » « less
4. A ±0.5-mV-Minimum-Input DC-DC Converter With Stepwise Adiabatic Gate-Drive and Efficient Timing Control for Thermoelectric Energy Harvesting

   https://doi.org/10.1109/TCSI.2022.3219402  

   Carlson, Eric J. ; Smith, Joshua R. ( February 2023 , IEEE Transactions on Circuits and Systems I: Regular Papers)

   This paper presents a step-up DC-DC converter that uses a stepwise gate-drive technique to reduce the power FET gate-drive energy by 82%, allowing positive efficiency down to an input voltage of ±0.5 mV—the lowest input voltage ever achieved for a DC-DC converter as far as we know. Below ±0.5 mV the converter automatically hibernates, reducing quiescent power consumption to just 255 pW. The converter has an efficiency of 63% at ±1 mV and 84% at ±6 mV. The input impedance is programmable from 1 Ω to 600 Ω to achieve maximum power extraction. A novel delay line circuit controls the stepwise gatedrive timing, programmable input impedance, and hibernation behavior. Bipolar input voltage is supported by using a flyback converter topology with two secondary windings. A generated power good signal enables the load when the output voltage has charged above 2.7 V and disables when the output voltage has discharged below 2.5 V. The DC-DC converter was used in a thermoelectric energy harvesting system that effectively harvests energy from small indoor temperature fluctuations of less than 1°C. Also, an analytical model with unprecedented accuracy of the stepwise gate-drive energy is presented. 

   more » « less
5. A Control Scheme for a DC Extreme Fast Charger with RMS Current Minimization

   https://doi.org/10.1109/PEDG51384.2021.9494232  

   Jean-Pierre, Garry ; Beheshtaein, Siavash ; Altin, Necmi ; Nasiri, Adel ( June 2021 , 2021 IEEE 12th Annual International Symposium on Power Electronics for Distributed Generation Systems)

   In this study, a power converter topology and control schemes for the power converter stages are proposed for a DC extreme fast charger. The proposed system is composed of a cascaded H-bridge (CHB) converter as the active front end (AFE), and an input series output parallel (ISOP), which includes three parallel connected dual active bridge (DAB) cells. A modified Lyapunov Function (LF) based control strategy is applied to obtain high current control response for the AFE. An additional controller to remove the voltage unbalances among the H-bridges is also presented. Additionally, the triple phase-shift (TPS) control method is applied for the ISOP DAB converter. A Lagrange Multiplier (LM) based optimization study is performed to minimize the RMS current of the transformer. The performance of the proposed converter topology and control strategies is validated with MATLAB/Simulink simulations. 

   more » « less