The 110 kV low voltage reactive power compensation equipment in 1 000 kV Nanyang substation has some specific characteristics and innovation compared with that in traditional EHV substation, such as the equipment principle, equipment capacity, connection mode, protection principle and control scheme. This paper introduces the connection scheme of double H type protection for large-capacity shunt capacitance bank. Because of the application of new 110 kV load breaker switch (LBS), both the trip protection of 110 kV reactive power and failure protection are level 2, and the particular trip scheme is used for bus dead zone fault. Due to the small auxiliary transformer capacity of UHV substation, some new problems are still existed in current transformer (CT) configuration, fixed value setting of relay protection and system testing, and correspondingly some solutions are proposed. Because of the particularity of connection mode of auxiliary power system in Nanyang substation, an optimization scheme on the scope of transformer current differential protection is put forward.