Marx generator

About: Marx generator is a research topic. Over the lifetime, 1276 publications have been published within this topic receiving 8970 citations.

Energy balance aspect in KALI-30 GW high-voltage pulse power source

Abstract: This paper elaborates the effect of unmatched stored energy in high-voltage high-energy pulsed power systems. High-voltage insulation failure of KALI system is analyzed thoroughly for its occurrence. According to the simulations and analysis energy mismatch of MARX generator and Blumlein transmission line is found to be the most significant cause for high-voltage failure of the system. MARX generator and Blumlein of KALI are redesigned to attain better energy balance at same voltage level. Observations, simulation and analytical results are illustrated in the following sections.

The DAHRT-II electron injector

Abstract: Author(s): Henestroza, Enrique | Abstract: The injector for the second axis of the Dual-Axis Radiographic Hydrotest Facility (DARHT) is being constructed at LBNL. The injector consists of a single gap diode extracting a 2 microseconds, 2kA, 3.2 MeV electron beam from a 6.5- inches diameter thermionic dispenser cathode. The injector is powered through an insulatoing column by a Marx generator. There is also the possibility of extracting a beam current of 4 kA. The focusing system for the electron beam consists of a Pierce electrostatic focusing electrode at the cathode and three solenoidal focusing magnets positioned between the anode and induction accelerator input. The off-energy components (beam-head) during the 400 ns energy rise time are overfocused, leading to beam envelope mismatch and growth, resulting in the possibility of beam hitting the accelerator tube walls. The anode focusing magnets can be tuned to avoid the beam spill in the 2kA case. To allow beam-head control for the 4kA case we are considering the introduction of time-varying magnetic focusing field along the accelerator axis generated by a single-loop solenoid magnet positioned in the anode beam tube. We will present the final design as well as beam dynamics calculations of the injector.

A novel compact low impedance Marx generator with quasi-rectangular pulse output.

Abstract: In this paper, a novel low impedance compact Marx generator with near-square pulse output based on the Fourier theory is developed. Compared with the traditional Marx generator, capacitors with different capacity have been used. It can generate a high-voltage quasi-rectangular pulse with a width of 100 ns at low impedance load, and it also has high energy density and power density. The generator consists of 16 modules. Each module comprises an integrative single-ended plastic case capacitor with a nominal value of 54 nF, four ceramic capacitors with a nominal value of 1.5 nF, a gas switch, a charging inductor, a grounding inductor, and insulators which provide mechanical support for all elements. In the module, different discharge periods from different capacitors add to the main circuit to form a quasi-rectangular pulse. The design process of the generator is analyzed, and the test results are provided here. The generator achieved pulse output with a rise time of 32 ns, pulse width of 120 ns, flat-topped width (95%-95%) of 50 ns, voltage of 550 kV, and power of 20 GW.

Design and operation of a fast-risetime, 500 Hz, 24 kV, optically-isolated pulse trigger generator

Abstract: This paper presents the design and performance characteristics of an optically isolated, trigger generator for spark gap applications that is capable of operating at over 500 Hz rep rate. The pulsed trigger generator is designed to achieve fast risetimes on the order of 1kV/ns to cause breakdown between the trigatron trigger pin and the opposite electrode. The pulsed trigger generator is designed to trigger a 10-stage, 500 kV, 42 J Marx generator. The system is capable of delivering a 4–25 kV pulse with a 10/90 risetime of 20 ns. A board was fabricated to control a capacitor charger and high voltage thyristor via fiber optic inputs. The capacitor charger, a 60 W constant current dc-dc power supply with variable voltage control, is capable of charging 1 nF in less than 0.3 ms. The system is battery-powered using a 33 V lithium polymer battery pack for isolated operation in noisy environments. For burst mode operation, a larger 250 nF buffer capacitor, which is initially charged, is connected through a 100 kΩ resistor to the trigger capacitor, which is varied between 1 and 40 nF. The value of the trigger capacitor is adjusted to provide optimum performance for a given transformer and magnetic switch. System modeling results along with experimental data are discussed including the reliability and performance of the overall system including jitter at 500 Hz operation.

Design and research of the discharge system of the pulse collimator

Abstract: In order to study the key technology of pulse x-ray for breast cancer diagnosis in medical system, a pulse punctual X-ray source system is developed. The system is composed of pulse source, pulse x-ray tube and optical focusing lens. The pulse source is composed of Marx generator, spark gap switch, capacitor voltage divider and output section, and the compact and movable design is adopted; the pulse x-ray tube is designed with a This method can effectively improve the repetition rate of x-ray point source location, and adjust the material and distance of anode and cathode according to different driving voltage; the focusing lens adopts the design of poly-capillary Xray lens, and uses the total reflection mechanism of X-ray in the lens, which has a large flux focusing Characteristic. The experimental results show that when the output voltage of the pulse source is 165kv, the rise time is about 10ns, and the pulse width is about 100ns, the system can radiate a pulse width nanosecond X-ray with a diameter of about 100 µ m and an energy of about 15kev, and the image of the organism can be obtained by using this ray.