Superconducting motor quench detection method and apparatus based on rotational symmetry of motor

A superconducting motor quench detection apparatus based on rotational symmetry of a motor, used for a superconducting motor, wherein the superconducting motor quench detection apparatus comprises:

• an acquisition module, configured to acquire terminal voltages of each group of superconducting magnets in the superconducting motor, wherein the superconducting motor is pre-divided into at least two unit motors that are arranged symmetrically with respect to a rotational axis and have identical electromagnetic structures by using the rotational symmetry of the motor, and the superconducting magnets at corresponding symmetric positions in the at least two unit motors have the same geometric structure;
• superconducting magnets located at corresponding positions are selected from the at least two unit motors as a group of superconducting magnets;
• the terminal voltages are acquired in real time and the terminal voltage of each superconducting magnet is coupled with an induced voltage and induced voltage components in the two superconducting magnets have same variation process;
• a calculation module, configured to calculate the terminal voltage difference between adjacent unit motors in the same group, where magnetic fields passing through the superconducting magnets at the same position n in adjacent unit motors have same waveform and variation process, so that the induced voltage components in the terminal voltages of the two superconducting magnets have the same variation process and the induced voltage components are eliminated in the terminal voltage difference, then calculate an absolute value of a terminal voltage difference of each group of superconducting magnets;
• and
• a judgment module, configured to judge whether the absolute value exceeds a preset threshold, and if the absolute value exceeds the preset threshold, to determine that the superconducting magnets are in a quench state;
• wherein comparing the obtained absolute values of the terminal voltage differences with the preset threshold, if both |Un(t−1)t and |Unt(+1)| are greater than the preset threshold, considering that the superconducting magnet located at the position n in the unit motor t is in the quench state, wherein Unt(t+1) is a difference between a terminal voltage of the superconducting magnet located at the position n in the unit motor t and a terminal voltage of a superconducting magnet located at a position n in a unit motor t+1.