3 results about "Current loop" patented technology

The invention discloses a three-stage synchronous motor rotor position estimation method based on a direct decoupling mode. A main exciter of a three-stage synchronous motor uses single-phase alternating current excitation with constant frequency, and a second harmonic wave generated by a rotating rectifier as a high-frequency signal is indirectly injected into an excitation winding of a main generator, a second-order generalized integrator is used for extracting a high-frequency response signal and an orthogonal signal thereof from current loop output controlled by starting of the main generator, high-frequency sine and cosine signals extracted from a stator side of a main exciter are combined, a decoupling signal synchronous with the high-frequency response signal is generated through analytical operation, a heterodyne method is combined for modulation, and a rotor position angle of the three-stage synchronous motor is estimated. According to the rotor position estimation method provided by the invention, the decoupling signal synchronous with the high-frequency response signal can be accurately generated, the calculation amount is small, implementation is easy, the complexity of a motor control algorithm can be effectively reduced, and the accuracy of the obtained position estimation angle is relatively high.

The invention discloses an automatic wind energy daily bird repelling device. The device comprises a rod body, wherein a mounting box is fixedly arranged at the top end of the rod body, a mounting cavity is formed in the mounting box, a plurality of main shafts are rotatably arranged in the mounting cavity, two magnets are symmetrically and fixedly arranged on the side walls of the main shafts, and power supply devices are fixedly mounted on the left cavity wall and the right cavity wall of the mounting cavity, each power supply device comprises two fixing rods, one ends of the plurality of fixing rods are fixedly connected with the inner side wall of the mounting cavity, coils are fixedly wound around the plurality of fixing rods, a buzzer is arranged in the mounting cavity, a mounting groove is formed in the upper surface of the mounting box, a photoresistor is arranged in the mounting groove, and the photoresistor is electrically connected with the buzzer and the coils to form a complete current loop. The bird repelling device can automatically work in the daytime and cannot work at night, and the phenomenon that the buzzer makes a sound at night to disturb residents is avoided.