Diversified Technologies, Inc., Bedford, Massachusetts, USA
Diversified Technologies Inc. (DTI) designed a modulator which meets the requirements of the Spallation Neutron Source (SNS) modulators at Oak Ridge National Laboratory and will be less expensive than copies of the current modulators. The SNS modulators, under development for a decade, still do not meet the specifications for voltage, droop, or pulsewidth. The modulators must provide pulses of 85 kV, 165 A, with pulsewidths of 1.5 ms and voltage flatness of 1%. The current modulator switches the full power at high frequency during each pulse, and has a complex output transformer. DTI designed a modulator that meets all specifications and is less expensive. The proposed design is cheaper because there is an HV switch that operates at full current only once per pulse, a corrector that switches only 5% of the power at high frequency, a low-cost transformer-rectifier power supply, and no output transformer. DTI’s patented switch uses IGBTs, allowing the switch to operate at full capacity even if 20% of the devices fail. The modulator will be installed in 2013 at SNS to test klystrons. DTI will present the system components of the design as well as the performance results to date.
Diversified Technologies, Inc., Bedford, Massachusetts, USA
Diversified Technologies, Inc. (DTI) is developing a driver for a kicker strip-line deflector which inserts and extracts charge bunches to and from the electron and positron damping rings of the ILC. The ILC damping ring kicker driver must drive a 50 Ω load at 10kV with 2 ns flat-topped pulses, which is to burst pulses at a 3 MHz rate within 1 ms bursts occurring at a 5 Hz rate. The driver must also absorb high-order mode signals emerging from the deflector. Key components include: HV MOSFET switch array capable of delivering 25 ns, 400 A, 1kV pulses at 3 MHz in 1 ms bursts, at a burst rate of 5 Hz; this switch array having a withstand capability of 4kV+; DSRD diode stack capable of withstanding 5kV upon opening (but later 10kV), able to open within 500 ps and interrupt 400 A reverse current; a 1 ns 50 Ω delay line, together with an input circuit that presents a near-short to the line for frequencies greater than 10 MHz. DTI has demonstrated a solid state kicker driver meeting ILC requirements, extendable to a wide range of kicker driver applications. The MOSFET array switch, without the DSRDs, is itself suitable for many accelerator systems with >10 ns kicker requirements.