Upgrade of beam steering system components and controls for the NSLS storage rings

The installation of the new insertion devices and new experiments on the NSLS (National Synchrotron Light Source) storage rings has increased the demand for better stability of the electron orbit. This, in turn, increased the demand for better stability and resolution as well as larger bandwidth of the orbit correction system. All of the orbit-correcting dipoles now have new low-hysteresis laminated steel cores. The magnets are excited by commercial wideband (1-kHz) current-regulated power supplies. The input circuits of the new power supplies permit a summation of analog inputs from orbit-stabilization systems with set-point inputs digitally controlled by the operator. The design of the new system is described, and its present performance is summarized.<>