RF HPA Procurement for ALS-U project — Summary Description

The Advance Light Source Upgrade (ALS-U) project at LBNL is an upgrade of the storage ring, its injection system and several beam lines of ALS, whose main objective is to achieve an increase in brightness and coherent flux of soft x-rays (at 1 keV) of at least two orders of magnitude beyond today’s ALS capabilities. The ALS-U project, includes design, development, construction, installation and commissioning of new systems in the ALS accelerator complex.

This procurement is for two 60 kW CW 500.394 MHz Radio Frequency (RF) High Power Amplifier (HPA) systems that will be part of the Accumulator Ring (AR) RF system in the ALS-U project. Each HPA shall provide continuous, round the clock (24/7), controlled, stable, high power radio frequency (RF) energy that will drive a normal conducting RF cavity, via a high-power circulator and 50-ohm transmission line, in the Accumulator Ring.  The HPA shall be turn-key, modular, fault-tolerant and self-protecting Solid-State High-Power RF Amplifier system based on LDMOS technology. The two identical HPA’s are to be installed indoor (on the roof of Booster ring), will be water cooled (for efficient heat removal), will have a high reliability (for continuous 24/7 operations) and the HPA will be of appropriate size so as to fit into constrained space, as available.  The high-power RF will be realized by combining the RF power from many RF Amplifier Modules.  There will be redundancy in the RF Amplifier Modules and DC power supply modules. In the event of up to 10% of the transistors failed and up to 15 % of the DC power supply modules failed, the HPA shall still provide the minimum output power of 48 kW. The selected RF LDMOS transistor for the RF Amplifier Modules shall have high ruggedness and it shall be protected from RF reflected power at its output by connecting a circulator with load, which shall always present a stable matched load to the RF Amplifier Module.

The HPA Engineering Specification Document (ESD) document provides the detailed specifications/ requirements for RF, electrical, mechanical, LCW cooling, control, thermal, seismic, environmental, reliability and construction requirements of the HPA. The HPA‘s controller will be a PLC and FPGA based control system with a local user interface and an EPICS compatible interface. The HPA control system shall be capable of monitoring, data logging, controlling and displaying the various signal parameters and it will provide the control and protection logic to make the HPA fault tolerant and to diagnose faults when they occur.

The HPA Statement of Work (SOW) document provides the detailed Vendor’s scope of work, obligations and responsibilities in the aforesaid procurement of two 60 kW CW 500MHz RF HPA’s. In the event of any conflict between the HPA ESD and the Statement of Work (SOW), the vendor shall immediately notify the LBNL representative, who shall in each instance determine which document takes precedence and advise the vendor accordingly. Failure to notify LBNL of a document conflict shall not relieve the vendor’s responsibility to ensure full compliance to all requirements.