Pulse Power Supply With Faster Response and Low Ripple Current Using Inductive Storage and Interleaving Technology

This paper presents a new interleaved pulsed power converter (P-IPPC) topology with improvement of current response speed for high-power semiconductor laser. The proposed P-IPPC topology consists of an interleaved converter, auxiliary circuit and pulse forming circuit, improving the current response speed and reducing output current ripple. The basic concept of this technology is to store energy in inductor by precharge method and releasing energy instantly to obtain a fast current rising edge response. Meanwhile, an auxiliary circuit is added to solve the problem of difficult digital pre-charge control of fast current response. As the driving load is stopped, the inductance energy is fed back to the power supply to realize the fast cutting off of the load current. MATLAB/Simulink simulation software is used to verify the proposed topology and pre-charge method. The simulation results show that the proposed topology and pre-charging method are effective. Compared with the conventional buck interleaved pulsed power converter topology, the current response speed is improved, and the problem of inductor limited current response speed is solved as well.

This work has adopted the concept of asymmetric inductor magnetization to develop a new quadratic converter with the advantages like a wide range quadratic voltage gain and low source current ripple. In addition, the proposed high quadratic converter has achieved reduced voltage stress due to the presence of switched capacitor cell at the output side. Initially, the operation of the converter and steady-state analysis, including efficiency calculations, are explained. In addition, the design and selection of converter components are presented along with a small-signal analysis. Further, a comprehensive comparison with recent high quadratic gain converters is presented. The comparison is made with regard to the total component count, voltage conversion ratio, effectiveness index, electric stress, current ripple, switching device power (SDP) rating, and input current ripple factor. Furthermore, the 150 W laboratory prototype is used to verify the performance of the proposed converter in terms of operation, dynamic response, and efficiency, and the corresponding experimental findings are reported. The wide range voltage gain, low current ripple, and low electric stress features of the proposed converter highlight its superiority in fuel cell electric vehicle applications.

An interleaved buck-boost converter with a wide conversion ratio is proposed in this paper. Two converter cells are used in the porposed converter. One is a single-ended primary inductor converter (SEPIC) and the other is a Cuk converter. Since both converter cells have an inductor and a switch, the input current of the proposed converter has low current ripple by utilizing an interleaving technique. The SEPIC converter cell provides a positive step up/down output and the Cuk converter cell provides a negative step up/down output. Therefore, the proposed converter has also step up/down capability and a wide conversion ratio. The proposed converter has a low input current ripple, step up/down capability, and a wide conversion ratio. Theoretical analysis and performance of the proposed converter were verified on an experimental prototype operating at 100 kHz switching frequency.

To balance the cost and volume when applying a low output current ripple, the power supply design should be able to eliminate the current ripple under any duty cycle in medium and high switching frequencies, and considerably reduce filter volume to improve power density. A stacked buck converter was eventually selected after reviewing the existing solutions and discussing their advantages and disadvantages. A stacked buck converter is used as a basis to propose the transient response and output current ripple elimination effect, boundary limit control method, and low output ripple dead time modulation method to make individual improvements. The principle, mathematical derivation, small-signal model, and compensator design method of the improvement method are presented in detail. Moreover, simulation results are used to mutually verify the correctness and effectiveness of the improvement method. A stacked buck converter with 330-V input, 50-V output, and 1-kW output power was implemented to verify the effect of the low output current ripple dead time modulation. Experimental results showed that the peak-to-peak value of the output current ripple was reduced from 2.09 A to 559 mA, and the RMS value was reduced from 551 mA to 91 mA, thereby effectively improving the output current ripple.

The model predictive direct speed control (MPDSC) can improve the speed dynamic performance effectively. However, due to the large difference between the mechanical and electrical time constants, short prediction could result in large current ripples at steady state, which becomes a critical problem. Besides, the conventional MPDSC methods have not deeply investigated the online-adjustable weighting factor design and the problem of <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">i_d</i> transient oscillation. In this article, a model predictive direct speed control with novel cost function is proposed. In the proposed method, two different <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">q</i> -axis current references are generated, one to improve the speed dynamics, and the other to ensure the low current ripples. The two current tracking are assigned with different weighting factors unified in one cost function. In order to determine which current tracking to play a major role under different operations, the speed error is designed as weighting factor. With the proposed cost function and designed weighting factor, the high speed dynamics and low steady current ripples can be achieved simultaneously. Finally, the effectiveness of proposed method is verified by experiments.

This paper proposes novel bidirectional DC-DC converter that has the advantages of high voltage gain, low conduction losses and low input current ripple. Two paralleled current-fed full bridges are located in the low voltage side (LVS), sharing one voltage-fed full bride in high voltage side (HVS). A quadruple phase-shift control strategy is proposed to reduce input current ripple and conduction loss. The phase shift between the full-bridges of LVS is employed to greatly reduce current ripple and the auxiliary inductors are used to help the lag bridge extend the zero-voltage-switch (ZVS) range. Finally, an 800W simulation prototype is built to verify the proposed converter, the accordance between the analysis and simulation results testify the advantages.

Battery Pack life time depending on thermal management is a crucial issue in Electric and Electric Hybrid vehicles. Excessive thermal losses caused by the battery current ripples can be well avoided by introducing suitable topology. This paper proposes utilization of interleaved DC-DC converters to reduce the battery pack current ripples. Interleaved converters have some advantages such as low current ripple, low losses and high reliability. This paper considers Ni-MH batteries used in Toyota Prius 2010 and takes the high frequency model of Ni-MH battery into account to show the effect of ripple current on battery. While design equations and considerations are explored, conventional converter and interleaved DC-DC converter are modeled and simulated to study and compare the battery current ripples in boost and buck modes of operation. It is shown that current ripples of interleaved converter are much lower resulting in extension of battery pack life time.

Alternative energy systems (AES) are becoming popular for small scale power generation. Designing the converters which transform the DC power into AC is the main development area of AES. Conventional single-phase voltage source inverter (VSI) uses buck topology which gives lower average output voltage than the input DC voltage. However, where the output voltage requirement is larger than the input DC voltage, such as uninterruptible power supply, fuel cell (FC) and photovoltaic systems, boost inverters are used. The boost inverter applied in this study consists of two boost DC-DC converters, which provides sinusoidal AC voltage output. The key drawback of the inverter lies in its control structure. In this paper, a dual loop control method is applied to ensure pure sinusoidal output voltage with fast dynamic response and low input current ripple. The input voltage of the inverter is assumed to be stable at 48 V considering commercially available FC voltage and the output voltage is regulated at 110 Vrms. In this article, the operating principle, mathematical modelling, analysis and control strategy of the boost inverter is presented. The proposed control strategy is verified with simulation using MATLAB/Simulink®. Simulation results show that the output voltage is 110 Vrms pure sinusoidal and the input current has low ripples.

In this paper, residential loads are modeled in order to analyze low frequency current ripples of residential fuel cell applications. A difference of low frequency current ripples between simple resistor load condition and actual residential load conditions is compared. Aspect of generation and propagation of low frequency current ripples are analyzed in order to design an optimal power conditioning system. Theoretical analysis has been performed and informative simulation and experimental results are provided.

SUMMARYIn this paper, we propose two control methods of a static impulse voltage generator to lower the influence of dc voltage source fluctuations on the output voltage and to improve its efficiency by reusing discarded inductive storage energy. Introducing output voltage control adjusting the charging period of capacitive and inductive energy in accordance with the source voltage, the output voltage fluctuation by the source voltage decreased by 61.1%. Applying the reusing method, we estimated by circuit simulation that the amount of energy that could be recovered was 21.0% and the efficiency of energy transfer was improved from 60.4% to 76.7%.

With the development of the global first fourth electron cyclotron resonance (FECR), plasma of highly charged ions produced under high microwave frequencies required to be constrained strictly by symmetric high magnetic field. Using pulsed power supply to generate the magnetic field has cost-effective advantage over superconducting power supply. In this paper, a pulsed power supply is utilized to generate symmetric high magnetic field. The pulsed power supply must provide large inductive loads with a fast pulse current ramping from 0A to 2700A between 50 ms and 70ms. The stability of current is 6×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-5</sup> and the repeatability of current is about 2×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-4</sup> at the flat top current waveform. For this purpose, a digital controller based on Xilinx 7000 FPGA is designed and implements a control strategy of double current loop in series. The experiment results show that the index of pulsed power supply is successfully fulfilled.

In order to meet the high current quality and low leakage current requirements in high power rating photovoltaic applications, an improved carrier-based modulation (ICBM) for parallel converters is presented in this article. Different from existing methods which are based on phase-shifted pulsewidth modulation, a proper zero-sequence modulation wave is injected into the three-phase modulation waves to achieve a low total current ripple based on the root mean square value analysis of the output current ripple. Aside from this, the initial phase shift angles for the carriers in each converter are modified to minimize the excitation source of leakage current, while the quality of total output current is not affected. Furthermore, the proposed ICBM is extended to parallel multilevel converters according to the vector shift principle. By using the proposed ICBM, total current ripple reduction and leakage current attenuation in parallel converters can be achieved simultaneously. Experimental results validated the correctness and effectiveness of the proposed method.

Development of the 320 kA pulsed magnetic horn power supply with a novel energy recovery system for the T2K experiment

This article investigates an innovative modulation technique for a predictive control applied to a synchronous reluctance motor (SyRM) drive. The new formulation of the duty cycles, in both linear and overmodulation regions, relies on the identified flux-versus-current characteristics. Furthermore, integral terms have been introduced in the predictive control to achieve satisfactory reference tracking performance with zero steady-state error, even under model parameters mismatches. Low current ripple with smooth and fast dynamic responses are achievable at fixed switching frequency over the whole current operating range. Simulations and experimental evidence show the effectiveness of the proposed controller against standard controllers such as field-oriented current control (FOC) and deadbeat current control (DBCC), guaranteeing low current ripple, robustness against parameters variations, and fast dynamic performance.

Inductive energy storage in conjunction with opening switch techniques has many advantages over conventional, capacitive power approaches for high-energy (>10MJ), high-power (>10l2W) applications.1 The principal advantages of inductive storage derive from the 10–100 times higher energy density possible with energy stored in magnetic fields as compared with electric fields and that energy can be stored at low voltage. In theory, this makes compact and economical generators possible.2 In any inductive storage scheme, the opening switches represent the most critical elements. One such possible switch is the plasma erosion opening switch (PEOS). This switch has been proposed to be used either by itself3 or in sequence with other opening switches4 in several inductive-store, pulsed-power systems. Recently, inductive-store/ pulse-compression techniques employing the PEOS have been successfully adapted to conventional pulsed-power generators for the purpose of improving their performance, e.g., peak voltage, peak power, and pulse width.5–11 In addition to inductive store applications, the PEOS has been used extensively in high power generators for prepulse suppression, improving power flow symmetry, and current risetime sharpening.5,6,12–18 Depending on the specific application, the PEOS has demonstrated opening times less than 10 ns, conduction times approaching 100 ns, conduction currents as high as 5 MA, and voltage generation over 3 MV without breakdown. Present research is directed toward obtaining a better understanding of PEOS physics and the interaction of the PEOS with the other system components to optimize system performance.