Huang, J.C. Chang, C.H. Chung, T.Y. Hwang, C.-S. Jan, J.C. Kitamura, H. Yang, C.K. Yang, C.S. JACoW Geneva, Switzerland 978-3-95450-182-3 10.18429/JACoW-IPAC2017-TUPAB106 English 1562-1565 TUPAB106 undulator vacuum permanent-magnet cryogenics radiation Contribution to a conference proceedings 2017 2017-05 http://dx.doi.org/10.18429/JACoW-IPAC2017-TUPAB106 http://jacow.org/ipac2017/papers/tupab106.pdf Development of a cryogenic permanent magnet undu-lator (CPMU) at the Taiwan Photon Source (TPS) is the most recent activity toward a new light source for the Phase-II beamlines. A hybrid-type CPMU with a period length of 15 mm is under construction with PrFeB permanent-magnet materials. A maximum effective magnetic field of 1.77 T at a gap of 3 mm is expected when the magnets (PMs) are cooled down around 77 K. The features desired for the TPS CPMU are low-intrinsic-phase-error characteristics and high thermal budget for various kinds of heat loads. The design of the TPS CPMU is discussed in this paper.