As the key equipment of power plants and substations, Transformers carry heavy responsibility of power transmission, distribution and transformation of voltage levels. Recent years, with the construction of UHV projects, the highest voltage level in China has increased to more than 1000kV and has formed several UHV networks, enhancing the reliability and efficiency of power supply. However,...
Nonlinear transmission lines (NLTLs) have been studied for application in aerospace radars, telecommunication, and medical devices. The radiofrequency (RF) pulses generated by the NLTLs can be radiated by antennas connected at the output of the lines. There have been relatively few articles that show experimental results regarding the transmission and receiving of RF signal generated by NLTLs...
The Virtual Cathode Oscillator (Vircator) is one of the methods to generate high power microwaves. Simplicity not needing external magnetic fields, and high-power capabilities are some of the advantages of Vircators. However, low efficiency is a serious problem. In the Vircator driven by ETIGO-IV generator, it is known that electron beam, 40% is lost at the mesh anode with transmittance of...
In a high power vacuum insulated transmission line, a critical current must be reached such that magnetic insulation is obtained. Before this magnetic insulation, the threshold for vacuum field emission is reached leading to emission of electrons from the cathode. Additionally, the large conduction currents lead to Joule heating of the electrodes and subsequent sublimation of any impurities...
A cancer treatment by an ultra-short pulse high electric field is one of new biological applications. This work focuses on the development of a high power nanosecond pulsed electromagnetic wave generator for the cancer treatment, and effect on a cancer cell by the developed device. We have developed a burst pulse generator that outputs the multiple pulses continuously by a NLTL (Nonlinear...
Ozone has been used for several applications as sterilization and deodorization because of the strong oxidizing power with low environmental load. The efficient and high-concentrated ozone-generation technology has been required. Ozone generation using nanosecond pulsed power has a feature of high efficiency but not high concentration. We have adopted a thin reactor in the ozone generation to...
Two pulsed power systems have been upgraded for the g-2 experiment at Fermilab. The Pbar Lithium Lens supply previously ran with a half sine pulsed current of 75 kA peak, 400 us duration and a repetition rate of 0.45 pps. For the g-2 experiment, the peak current was reduced to 25 kA, but the repetition rate was increased to an average of 12 pps. Furthermore, the pulses come in a burst of 8...
During the last two decades, HPM (High Power Microwaves) effects on systems such as electronic devices and sometimes biological samples have been studied in CEA/Gramat. These studies led to actual designs of several HPM generators, each corresponding to a specific technology or experimental area. This paper presents two high-sized electromagnetic simulators named Hyperion and MELUSINE.
The...
This paper describes a high-speed imaging setup for capturing exploding detonators with short exposure time cameras. With three, commercially available, high intensity, pulsed xenon light sources (> 107 candela intensity) satisfactory image quality was achieved for a minimum exposure time. Beyond that the combined flash lamp output was too dim at desired shorter exposure times. As such, an...
Ablation outcome assessment is critical for confocal therapy. Irreversible electroporation (IRE) is a new emerging tumor treatment in recent years. The variation of the impedance has been proved the ability to reflect the treatment outcome of IRE. However, nowadays the impedance is mostly measured by the treatment electrodes which are used to apply pulses. The information obtained by that is...
Nowadays Nonlinear Transmission Lines-NLTL have been studied for RF generation to be applied in different systems of communications such as satellite, military and biomedical applications. NLTL is built by using a network composed by inductors and capacitors, where at least one of these components need to have a nonlinear behavior. One limiting factor for applications is in the peak power...
To understand effects of processing and surface chemistry on nanodielectric material properties, we study interaction of molecular species used in synthesis, functionalization, and suspension of BaTiO3 particles in solution. We investigate interaction of water with BaTiO3 using density functional theory (DFT) applied to slab configurations. Slabs meant to represent the environment of a...
Linac Coherent Light Source (LCLS) at SLAC has started to run since April, 2009 and is driven by eighty-four klystrons. Each klystron is powered by a line-type modulator with a high power thyratron as a switch. The thyratron life time has become an important concern since its invention. SLAC has accumulated thyratron life data in past long time operation. In this report, we will review the...
At the Frankfurt Neutron Source (FRANZ), it is intended to generate a neutron beam with energies up to 300 keV by a pulsed proton beam with the Li7(p,n) reaction. To prebunch the proton beam for FRANZ, a 6 kV chopper with a repetition rate of 256 kHz and a pulse width of 100 ns has been designed and build. The current pulse generator bases on transformers and therefore forms a clipped and...
Several prototype inductive adders (IAs), for use with kicker systems, each with very different specifications, are under construction at CERN. Historically pulse generators for kicker systems use thyratrons and either a Pulse Forming Network (PFN) or a Pulse Forming Line (PFL). The IA has several advantages compared to these conventional pulse generators, including: the use of semiconducting...
Nonlinear transmission lines (NLTLs) have been used with great success to generate high power radio frequency (RF). Generally, their operation consists of a lumped line based on the nonlinear behavior of the LC section components, capacitors or inductors, as a function of the applied voltage or current, respectively. However, considering high power signals, the employment of ceramic...
A fast travelling wave kicker operating with 80 MHz repetition rates is required for the new PIP-II accelerator at Fermilab. We present a technique to drive simultaneously four series-connected enhancement mode GaN-on-silicon power transistors by means of microwave photonics techniques. These four transistors are arranged into a high voltage and high repetition rate switch. Using multiple...
A low impedance modulator made up of ceramic-loaded parallel-plate transmission line sections in a Marx configuration has been developed as a test bed for high power microwave sources. The generator has configurable impedance between 15 and 25 ohms, pulse-width between 50 and 200 ns, and can operate at repetition rates up to 100 Hz with a 200 kW high voltage power supply. The energy stored in...
