Capacitor Block Research Articles

Инновационный способ утилизации отходов монолитных строительных конструкций

Introduction. During the reconstruction and technical re-equipment of various mining facilities, there is a need for the processing of concrete and reinforced concrete products that require environmental protection. The article analyzes innovative methods of destruction of hard rocks based on the use of electrohydraulic effect. The possibility of their use as an alternative environmentally friendly method of recycling reinforced concrete products is evaluated. A schematic diagram of an electrohydraulic installation for use for these purposes is presented. Based on the analysis of the mechanism of destruction of concrete and reinforced concrete products, the main electrical parameters that ensure the effectiveness of its application are substantiated. An assessment of the effectiveness of the implementation of the proposed technology in the process of recycling reinforced concrete structures was carried out. Materials and methods. After the main dismantling activities, the issue of removal and utilization of construction waste is solved, which requires its shredding. When using electrohydraulic technology for demolition of reinforced concrete, this production process includes: prior to processing – segmentation of structures by means of excavator hydraulic shears into fragments up to 1 m3 in size; placing them on the support grid of the EGU bath filled with water; grounding of the fittings; installation of working arresters in the bath and energizing of the EGU; after treatment – removal of the reinforcement cleaned from concrete from the bathtub; removal of the basket with concrete rubble from the EGU; storage of treatment products; installation of the released basket in place. Results and discussion. As a result of the research the organization of the production process of recycling of reinforced concrete fragments of building structure during their disposal using the technology of electrohydraulic crushing of concrete blocks at the site of their dismantling is proposed. Rational values of parameters of the organization of the destruction process in the EGU have been established: the distance from the arrester axis to the point of reinforced concrete blocks in the liquid volume; capacitance of the capacitor block; voltage at the moment of breakdown; inductance of the discharge circuit; cyclic frequency of oscillations. When using water as a working fluid, it is reasonable to vary the frequency of discharge pulses within 0.5...2.0 Hz. It has been established that the productivity of the single-electrode unit at the destruction of reinforced concrete to the final coarseness of 20 mm reaches 100 kg/h at a specific energy consumption of 120 kW/t. The use of 4-electrode EGU can ensure the crushing of one ton of reinforced concrete to a fraction of 20 mm in 2.5 hours. Increasing the overall environmental friendliness of the whole process of utilization of reinforced concrete products can be ensured by replacing the mechanical destruction of products by hydraulic shears with dust-free destruction by means of generation of a high-voltage current pulse by an electrode in a borehole filled with water. Сonclusion. According to the results of the conducted research, it is clearly seen that the proposed technology of electrohydraulic crushing of concrete blocks is a promising solution for effective utilization of reinforced concrete structures in the mining industry. Organization of the production process of recycling at the site of dismantling using this technology not only reduces the cost of transportation of materials, but also contributes to reducing the negative impact on the environment. The established rational parameters of the destruction process in the electrohydraulic unit provide the basis for optimization of the technology, which, in turn, provides precise regulation of the recycling process and increases its efficiency. Thus, the research results indicate that the proposed electrohydraulic shredding technology is a promising direction for the development of effective and environmentally friendly methods of construction waste utilization.

Modeling of System-Level Conducted EMI of the High-Voltage Electric Drive System in Electric Vehicles

Aiming at the problem of electromagnetic compatibility caused by the high-voltage electric drive system (HEDS) in electric vehicles, a model of the HEDS based on the vehicle is established to predict conducted electromagnetic interference (EMI) of the HEDS. First, the electromagnetic environment inside electric vehicles is analyzed theoretically. Then, the various parts of the HEDS are accurately modeled, which include the power buses, inverter, and motor. Based on the theory of multiconductor transmission line, a generic model of power buses suitable for two screening designs is presented. In order to accurately simulate the operating characteristics of the inverter, the drive circuit and the parasitic parameters of the dc-link capacitor block and the insulated gate bipolar transistor module are considered. The motor model takes into account the low-impedance antiresonance phenomenon in the measured motor impedance. Finally, the HEDS is simulated with PSPICE 16.6, and the simulation results agree well with the experimental measurements. The proposed model can accurately predict the system-level conducted EMI of the vehicle-mounted HEDS up to 100 MHz, with an error of 4 dB or less at almost all frequencies below 56 MHz and less than 7 dB at most frequencies in the 56–100 MHz.

A three-stage OTA with hybrid active miller enhanced compensation technique for large to heavy load applications

A three-stage amplifier with hybrid active Miller enhancement compensation is proposed in this paper, which is used for large to heavy load applications. The hybrid active Miller enhancement compensation (HAMEC) is composed of an amplified cascode Miller capacitor block and a local active compensation network. The sub-threshold transconductance enhanced compensation (STEC) amplifying block consists of a sub-threshold amplifier and a cascode capacitor, which effectively broadens the complex-poles frequency and improves the loop stability. A novel slew rate enhancement structure is also proposed to improve the transient response under large signal conditions. The amplifier has been verified in a 0.18 μm CMOS process. After simulation verification, the capacitive loads of 0.5pF-20nF can be driven, meanwhile, a gain bandwidth of 2.98–9.76 MHz can be achieved. It only consumes 41.28 μW power when driving a 20 nF capacitor load under 1.2 V power supply, and compensation capacitor size is only 475 fF. Finally, the figure of merits (FoM) value is effectively improved compared with recent work.

Numerical analysis for inhomogeneous compressive deformation of Multi-Layered Ceramic Capacitor block

Numerical analysis for inhomogeneous compressive deformation of Multi-Layered Ceramic Capacitor block

DC-link Ripple Reduction in a DPWM-Based Two-Level VSI

This paper proposes a new method to reduce the ripple current of the DC-link capacitor in a two-level voltage source inverter (VSI), with a discontinuous pulse-width modulation (DPWM). In real applications, a capacitor block is very bulky, due to the parallel connection of several capacitors that share the value of the ripple current. Hence, it contributes significantly to the volume and weight of the whole system. Conventional DPWM is used to minimize the amount of switching for the power transistors, therefore, reducing stress and power loss. This leads to increased efficiency and reliability of the system. Nevertheless, the reduction of the DC link ripple current is still not optimal. Therefore, the proposed method introduces a PWM phase-shift technique to provide further reduction of the DC-link ripple current in a DPWM-based VSI. The efficacy of the proposed method is confirmed by simulation and experimental results.

Design of Capacitor Blocks with Multi-Channel Switches for Linear Transformer Driver Stages

In the linear transformer driver technology, the low inductance energy storage components and switches are directly incorporated into the individual cavities (named stages) to generate a fast output voltage pulse, which is added along a vacuum coaxial line like in an inductive voltage adder. In this paper, we outline the detailed design concept and the basic parameters of four capacitor blocks with four different types of multi-channel gas switches. The 100 kV capacitor block #1 and #2 incorporate two parallel capacitors (40 nF, 100 kV) and multi-gap multi-channel gas switches with triggering plate or triggering cable. The 200 kV capacitor block #3 and #4 incorporate two capacitors (40 nF, 100 kV) in series and rail-gap gas switches with one triggering rail or two triggering rails. Operating principles of four multi-channel gas switches are illustrated by using the equivalent electrical scheme of each switch. The basic characteristics of four capacitor blocks are given. The effect of stray capacitances on the trigger pulses is also discussed.

Design of tunable optimal load circuit for maximum wireless power transfer efficiency

ABSTRACTA tunable optimal load circuit (OLC) for maximum wireless power transfer efficiency is presented for a magnetically coupled resonant system at 13.56 MHz. The OLC is required to transform the standardized 50 Ω receiver impedance to an optimal load to achieve maximum efficiency without using cumbersome feeding loops. The OLC based on a lumped‐element impedance converter is fabricated on a FR‐4 substrate. The size of the OLC is 25 × 50 mm. The series branch of the OLC is composed of a tunable series capacitor block and an inductor. The shunt branch of the OLC consists of a varactor and a capacitor block with switches. The theoretical and experimental results both showed that even though the loss in the inductor somewhat limits the achievable maximum efficiency, the efficiency with OLC is significantly enhanced compared with that without OLC. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:2619–2622, 2014

Capacitor blocks for linear transformer driver stages

In the Linear Transformer Driver (LTD) technology, the low inductance energy storage components and switches are directly incorporated into the individual cavities (named stages) to generate a fast output voltage pulse, which is added along a vacuum coaxial line like in an inductive voltage adder. LTD stages with air insulation were recently developed, where air is used both as insulation in a primary side of the stages and as working gas in the LTD spark gap switches. A custom designed unit, referred to as a capacitor block, was developed for use as a main structural element of the transformer stages. The capacitor block incorporates two capacitors GA 35426 (40 nF, 100 kV) and multichannel multigap gas switch. Several modifications of the capacitor blocks were developed and tested on the life time and self breakdown probability. Blocks were tested both as separate units and in an assembly of capacitive module, consisting of five capacitor blocks. This paper presents detailed design of capacitor blocks, description of operation regimes, numerical simulation of electric field in the switches, and test results.

MODELING AND UTILIZATION OF AN IPMC MUSCLE

Artificial muscles are one of the most important applications of the technology of flexible structure, designed to imitate human or animal muscles and to monitor its activities and conditions. The aim of our paper is to study the different possibilities of modeling and usage of artificial muscles. Our application is based on three IPMC muscles used to simulate a three fingers grasp. The magnitude of the voltage is utilized to compute the buildup columbic load using the capacitor block in the model. Keywords— Artificial muscle; IPMC Ionic Polymer Metal Composit; Modeling.

Pulse generators based on air-insulated linear-transformer-driver stages

In this paper we present the design and test results of pulse generators based on air-insulated linear-transformer-driver stages that drive a vacuum transmission line. A custom designed unit, referred to as a capacitor block, was developed for use as a main structural element of the transformer stages. It incorporates two capacitors GA 35426 (40 nF, 100 kV) and a multichannel multigap gas switch. Two types of stages were developed: (1) stage LTD-20 with four modules in parallel and five capacitor blocks in each module (in tests of this stage current amplitude up to 850 kA with $\ensuremath{\sim}140\text{ }\text{ }\mathrm{ns}$ rise time was obtained on a $0.05\text{ }\ensuremath{\Omega}$ load at 100 kV charging voltage); (2) stage LTD-4 with two modules in parallel and two capacitor blocks in each module. Several installations were built on the base of these stages, including a linear transformer, consisting of two identical LTD-20 stages in series, and a high power electron accelerator on the base of LTD-4 stages. The design, tests results, and main problems are presented and discussed in this paper for these installations.

A compact submicrosecond, high current generator

Pulsed current generator was developed for experiments with current carrying pulsed plasma. Main parts of the generator are capacitor bank, low inductive current driving lines, and central load part. Generator consists of four identical sections, connected in parallel to one load. Capacitor bank is assembled from 24 capacitor blocks (100 kV, 80 nF), connected in parallel. It stores 9.6 kJ at 100 kV charging voltage. Each capacitor block incorporates a multigap spark switch, which is able to commute by six parallel channels. Switches operate in dry air at atmospheric pressure. The generator was tested with an inductive load and a liner load. At 17.5 nH inductive load and 100 kV of charging voltage it provides 650 kA of current amplitude with 390 ns rise time with 0.6 ohms damping resistors in discharge circuit of each capacitor block. The net generator inductance without a load was optimized to be as low as 15 nH, which results in extremely low impedance of the generator (approximately 0.08 ohms). It ensures effective energy coupling with a low impedance load such as Z pinch. The generator operates reliably without any adjustments in 70-100 kV range of charging voltage. Jitter in delay between output pulse and triggering pulse is less than 5 ns at 70-100 kV charging voltage. Operation and handling are very simple, because no oil or purified gases are required for the generator. The generator has dimensions 5.24x1.2x0.18 m(3) and total weight about 1400 kg, thus manifesting itself as simple, robust, and cost effective apparatus.

Dissipation, voltage profile and Lévy dragon in a special ladder network

A ladder network constructed by an elementary two-terminal network consisting of a parallel resistor–inductor block in series with a parallel resistor–capacitor block sometimes is said to have a non-dispersive dissipative response. This special ladder network is created iteratively by replacing the elementary two-terminal network in place of the resistors. In this paper, it will be demonstrated that, in fact, non-dispersive dissipative response conclusion of this special ladder network is not accurate for steady-state condition. Furthermore, the voltage profile of this special ladder network exhibits a fractal form called the Lévy C curve or Lévy dragon in a certain condition. Therefore, this special ladder network may be called the Lévy ladder network. This ladder network might be interesting for physics and electrical engineering students and they may encounter when dealing with this network series and parallel combinations of impedances.

Capacitor Bank Module for a Multimegajoule Energy Storage

Laser megajoule (LMJ) is a laser facility being built by the French nuclear science directorate, Commissariat a l'Energie Atomique. This facility is a large flashlamp pumped laser (1.8-MJ optical output). The pulsed power conditioning system of LMJ is based on a modular design of 480 modules (400-MJ energy capacitor bank). A new capacitor bank module (CBM) for the LMJ power conditioning system has been developed by the Institute of High Current Electronics (IHCE, Tomsk) in collaboration with International Technologies for High Pulsed Power (France). Two such modules were produced and tested in IHCE. The main parts of the CBM are the following: high-voltage power supplies, command control system, air conditioning system, capacitor block, and cables delivering the energy to a load. The parameters of the module are the following: total rated capacitance of 2900 (+4%) muF, charging voltage up to 24 kV, peak current amplitude of 240 kA, peak stored energy up to 864 kJ, pulsewidth at 10% of peak power of 360 mus, dimensions of 2.3 times 1.5 times 2.5 m3, and weight of ~2500 kg. In nominal regime (24-kV charging voltage, 40-m length cables), the energy delivered to flashlamps in each channel is 74 kJ (86% efficiency). No failures were observed in more than 1000 test shots, and all parameters of the CBM are well within the requirements. Detailed description of the module design, performance, and test results are stated in this paper.

A 16-μA interface circuit for a capacitive flow sensor

A micropower interface circuit is described for fluidic flow measurement in commercial gas meters. The application-specific integrated circuit converts dynamic capacitive-flow sensor readings from 1 to 150 Hz into digital pulses suitable for reading by the host microcontroller. The signal path is first-order /spl Delta//spl Sigma/ modulation followed by a three-pole, one-zero infinite impulse response bandpass filter. Analog signal processing is fully differential switched capacitor, with amplifiers and dc current consuming blocks operating in weak inversion. Chip bias and oscillator frequency, and capacitive sensor offset and gain, are trimmed with on-chip EEPROM. Operating ranges are 2.5-3.6 V and from -10 to 65/spl deg/C, with active I/sub dd/ of 16 /spl mu/A.