An initial design for the feed-forward control (FFC) has been proposed for the dual elliptically polarized undulator (DEPU) which operating in SSRF. In order to reduce the orbit distortion during movement of the DEPU gap and shift, the feed-forward correcting magnetic field must be put at the entrance and exit of the DEPU must be taken [1]. The FFC is implemented in an individual controller which is independent of the DEPU motion controller, so that the regulation of correction currents would follow the gap and shift alteration real-timely and accurately in case gap or shift changes fast. According to one 2D look-up table (LUT) CCPS controller calculates the excitation currents for entrance and exit coils of the DEPU. The 2D LUT is composed of different gaps, shifts and corresponding currents acquired during the DEPU commissioning procedure.
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