approximate circle
1.In the second part, with the simulation tool Matlab/Simulink, the simulation experiment on hexagon flux track controlling DTC system and approximate circle flux track controlling DTC system is realized. Especially for the latter system, the operation of the start-up, low-speed, middle and high speed, field-weakning is simulated and analyzed.
2.The multifinger logging tool is an important tool acquiring casing deformation degree of water-oil well, The data that logging tool acquiring is interpreted by optimization method,circular center,maximum diameter and efficient diameter of approximate eccentric circle for deformation section are given.It provides scientific basis for interpreting casing deformation.
