Design procedure of an active bouncer for an ultra precise long pulse solid state modulator

Abstract

Long pulse modulator systems like the electronpositron compact linear collider (CLIC) with a pulse length of 140 µs require a bouncer for voltage drop compensation. In this paper, an active bouncer system, consisting of four bouncer modules, in series to the main capacitor bank, is investigated. The system's transfer function including the matrix pulse transformer is analysed and the output voltage ripple induced by the bouncer system is designed to be smaller than 5 ppm due to demanding repeatability requirement of CLIC. Based on a loss analysis is conducted resulting in a total bouncer system volume of 52 dm 3 and a reduction in the global efficiency (grid to klystron) of the modulator system of only 0.45 %.

Efficiency Potential of Solid-State Pulse Modulators using SiC Devices

“…Moreover, the bouncer specifications along with the devices that are used for the Si-based and the SiCbased bouncer module are shown in table III. In [16], a detailed explanation of the bouncer operation can be found. During the charging time t ch , the high-side switch S HS , and the short-circuit switch S SC are on.…”

“…Consequently, the inductor current slope is known and the losses of the switches can be calculated analytically. Then, the inductor current slightly decreases during t w for ensuring equal current sharing between the interleaved branches [16].…”

Control of an active bouncer for an ultra precise 140 μs-solid state modulator system

“…Due to the series connection, the bouncer modules must provide the primary pulse current as well as a charging current for their output capacitors. To provide the required pulse current fast enough, this current is build up prior to the pulse interval in the bouncer module inductance [5]. In order to reduce the modulator system complexity, the bouncer modules are charged together with the main capacitor bank with one charging system.…”

“…Therefore, the basic concept of an interleaved buck-boost topology with short circuit switch has been proposed in [5], which is able to provide the required current rate of change. In this paper an active bouncer converter is realized based on the analysis of [5] and its control during the pulse intervals as well as the charging processes are presented. One of the most challenging requirements of CLIC is the pulse to pulse repeatability, i.e.…”

Design of a real-time acquisition system for the CLIC klystron modulators control loop

“…In order to reach the desired energy level, together with a reasonable power consumption from the electrical grid, CLIC power converters [6] are demanded to deliver a pulsed power repeatable in the order of few tens of ppm [7]. To do that, a highvoltage modulator is currently under design by the lab for high-power electronics system at ETH Zurich (CH) [8] and the LEEPCI lab at Laval university (CA) [9]. The latest topology of the ETH design is depicted in Fig.2.…”