A redundant resolver comprising a rotor and a stator that form a pair, wherein the rotor is a rotor with a shaft angle multiplier of Nx having Nx salient poles, wherein Nx is a natural number equal to or more than 2, the stator is such that n teeth (T1 to T14), where n is a natural number equal to or more than 2, are disposed sequentially in a circumferential direction, configuring M systems by being divided into M in the circumferential direction, wherein M is a natural number equal to or more than 2, and having an angle of 360/M degrees when angles of the teeth configuring one system are totaled, wherein the teeth comprises first system teeth (T1 to T7) used in a first system and second system teeth (T8 to T14) used in a second system; a one-phase excitation winding (R1 to R14) and a two-phase output winding (Sa1 to Sa14, Sb1 to Sb14) are wound around each of the n teeth (T1 to T14); wherein first system excitation windings (R1 to R7), first first system output windings (Sa1 to Sa7), and second first system output windings (Sb1 to Sb7) are wound around the first system teeth (T1 to T7); wherein second system excitation windings (R8 to R14), first second system output windings (Sa8 to Sa14), and second second system output windings (Sb8 to Sb14) are wound around the second system teeth (T8 to T14); wherein the first and second excitation windings (R1 to R7, R8 to R14) are connected to a first and a second excitation circuit (10, 11) respectively; wherein the first first system output windings (Sa1 to Sa7) and the second first system output windings (Sb1 to Sb7) are connected to a first system angle computing unit and the first second system output windings (Sa8 to Sa14) and the second second system output windings (Sb8 to Sb14) are connected to and a second system angle computing unit respectively; an output order of the output windings per system is a natural number, and an abnormality is detected based on output signals of the M systems; wherein when an angle detected by the first system is θ1 and an angle detected by the second system is θ2, it is determined that there is an abnormality when | θ1 - θ2 | > α or | θ1 + θ2 | > β, wherein α and β are real numbers. the rotor is a rotor with a shaft angle multiplier of Nx having Nx salient poles, wherein Nx is a natural number equal to or more than 2, the stator is such that n teeth (T1 to T14), where n is a natural number equal to or more than 2, are disposed sequentially in a circumferential direction, configuring M systems by being divided into M in the circumferential direction, wherein M is a natural number equal to or more than 2, and having an angle of 360/M degrees when angles of the teeth configuring one system are totaled, wherein the teeth comprises first system teeth (T1 to T7) used in a first system and second system teeth (T8 to T14) used in a second system; a one-phase excitation winding (R1 to R14) and a two-phase output winding (Sa1 to Sa14, Sb1 to Sb14) are wound around each of the n teeth (T1 to T14); wherein first system excitation windings (R1 to R7), first first system output windings (Sa1 to Sa7), and second first system output windings (Sb1 to Sb7) are wound around the first system teeth (T1 to T7); wherein second system excitation windings (R8 to R14), first second system output windings (Sa8 to Sa14), and second second system output windings (Sb8 to Sb14) are wound around the second system teeth (T8 to T14); wherein the first and second excitation windings (R1 to R7, R8 to R14) are connected to a first and a second excitation circuit (10, 11) respectively; wherein the first first system output windings (Sa1 to Sa7) and the second first system output windings (Sb1 to Sb7) are connected to a first system angle computing unit and the first second system output windings (Sa8 to Sa14) and the second second system output windings (Sb8 to Sb14) are connected to and a second system angle computing unit respectively; an output order of the output windings per system is a natural number, and an abnormality is detected based on output signals of the M systems; wherein when an angle detected by the first system is θ1 and an angle detected by the second system is θ2, it is determined that there is an abnormality when | θ1 - θ2 | > α or | θ1 + θ2 | > β, wherein α and β are real numbers.