Quasi resonant pulse modulator for surface-dielectric-barrier discharge generation

vA surface dielectric barrier discharge (SDBD) reactor provides homogeneous plasma over a large area. Here we present a solid-state pulse modulator to generate SDBD plasma. It is able to generate 7 kV, 2 µs pulses at 15 kHz and 125 W. The presented pulse modulator is able to recover a large part of the remaining capacitive energy after each pulse. The paper presents the basic concept, practical implementation, voltage and current characteristics, loss analysis, and SDBD discharge behavior

Characterization of a surface dielectric barrier discharge

A surface dielectric barrier discharge (SDBD) reactor provides a homogeneous plasma over a large surface area. This allows surface treatments of foils, textiles or fibers. Here we present results of a study to characterize the AC and pulsed performance of SDBD with regard to ozone production, equivalent electrical model, and fast imaging of the plasma development

Quasi resonant pulse modulator for surface-dielectric-barrier discharge generation

vA surface dielectric barrier discharge (SDBD) reactor provides homogeneous plasma over a large area. Here we present a solid-state pulse modulator to generate SDBD plasma. It is able to generate 7 kV, 2 µs pulses at 15 kHz and 125 W. The presented pulse modulator is able to recover a large part of the remaining capacitive energy after each pulse. The paper presents the basic concept, practical implementation, voltage and current characteristics, loss analysis, and SDBD discharge behavior

A solid-state 0–120 kV microsecond pulse charger for a nanosecond pulse source

In this paper we present a solid state 0-120 kV microsecond pulse charger for our nanosecond pulse generator [1]. The pulse forming line of our nanosecond pulse generator must be charged with microsecond pulses to prevent pre-firing of its oil spark-gap. The pulse charger consists of two identical compact pulse charger modules with integrated electronics. The electronics are mounted on a compact PCB and consist mainly of a number of parallel connected IGBT's that switch a primary capacitor bank into a pulse transformer. Each pulse charger module can generate 60 kV microsecond pulses into a 250 pF load at 1 kHz repetition rate. Connected together they are able to deliver up to 120 kV into a 100 pF load. This 100 pF load is the pulse forming line of our nanosecond pulse generator at its maximum length of 1 m. The pulse charger is able to operate in an EMI unfriendly environment due to its compact lay-out and optical triggering of the IGBT's

Energizing a long nanosecond pulsed corona reactor: electrical characterization

Industrial application of nanosecond pulsed corona technology for air purification requires high volume, high power plasma reactors. Cylinder-wire type reactors require multiple cylinders or very long reactors to meet these demands. In this article, we focus on the characterization of a pulsed corona plasma in a long (4.5 m) plasma reactor. The reactor cylinder acts as a coaxial transmission line wherein high-voltage pulses propagate with close to the speed of light. Interactions between plasma generation and reflection behavior inside the reactor are expected and therefore investigated. A 4.5-m-long corona reactor is constructed and equipped with voltage and current sensors at multiple positions along the reactor length. A lumped element SPICE model is developed to simulate the reflection behavior. Strong reflections at the end of the reactor are observed for pulse rise times which are shorter than the transient time of the reactor. Plasma generation and energy distribution in the reactor, as well as impedance matching between source and reactor, are affected by these reflections. We investigate the role of the input voltage and rise time and analyze the electrical characterization, impedance characterization, and reactor efficiency

A fast 30 kV 5 kHz repetition rate resonant capacitor charger

A novel circuit topology of a fast 30 kV resonant capacitor charger is presented in this paper. The charger is designed for high repetition rate spark gap based pulsed power modulators. A spark gap can fire spontaneously (pre-firing) during charging of a capacitor bank due to poor dielectric recovery. The resulting near short circuit of the output can be handled repetitively by the circuit. A 15 kW prototype has been built and experimental results are presented. The charger is capable of charging a 8.4 nF capacitor to 30 kV in 35 μs with 91 % efficiency. The maximum repetition rate of this 3.8 J/cycle charger is 5 kHz. An active reset circuit for resetting of the pulse transformer core has been implemented. This circuit is also capable of recovering a large part of the energy which is stored in the stray capacitance of the secondary pulse transformer winding. A numeric simulation tool based on state space modeling is used to simulate circuit behavior. Measurements and simulations are in good accordance. A control loop is implemented to regulate the output voltage. The control scheme features a look up table which is dynamically updated to correct instabilities generated by random pre-fire events