Patents
Literature
Patsnap Copilot is an intelligent assistant for R&D personnel, combined with Patent DNA, to facilitate innovative research.
Patsnap Copilot

248 results about "High speed control" patented technology

Permanent magnetism synchronous electric machine - compressor system high speed operation control method

Disclosed is a high-speed control method for a permanent magnet synchronous motor-compressor system, including the following steps: initial design is carried out; a motor is detected through DSP, including detecting the two-phase current of the stator of the motor, the voltage Udc of a DC generatrix; the voltage of a d-p shaft is calculated; faults of overcurrent, overpressure and undervoltage are detected; if any fault exists, the PWM pulse signals are blocked and then the control program is paused; if no fault exists, the following steps will be carried out; the rotating speed of the motor and the position of the rotor are identified in the process of speed-position estimation; the current and the voltage of the reference d-q shaft of the motor are calculated; switching signals of an inverter are acquired through haplotype over-modulation; the data are recorded and waveforms are displayed; judgment of whether to pause the control program is carried out; if not, the second step is carried out again; if yes, the control program will be paused. The control method applies haplotype over-modulation method into the permanent magnet synchronous motor-compressor system, realizing sensorless over-modulation to the synchronous motor-compressor vector control system.
Owner:TSINGHUA UNIV

Engine Control Device, And Its Control Method

A first target engine speed Nh and a high-speed control field F1 are set in accordance with a command value by command means. A second target engine speed N2 on the low rotation side and a high-speed control field F2 are set based on the first target engine speed Nh. When a matching point between an engine load and an engine output torque exceeds a first set position A which is a first predetermined pump displacement during control of an engine in the high-speed control field F2, the high-speed control field F2 is shifted toward the high-speed control field F1. Using, as a new high-speed control field, a high-speed control field 3 in which a differential pressure between a pump discharge pressure and a load pressure of an actuator satisfies a load sensing differential pressure in a pump control device 8, the engine is controlled in the high-speed control field 3, and when the differential pressure does not satisfies the load sensing differential pressure, the speed control field is shifted to the high-speed control field F1. With this, it is possible to provide an engine control device and a control method thereof in which the fuel economy of the engine is enhanced, and when the maximum speed of an operating machine is required, the required maximum speed of the operating machine is not lowered.
Owner:KOMATSU LTD

Device and method for controlling slewing mechanism of tower crane

ActiveCN102642775ATroubleshoot boom swingSolve the problem of tower shakingCranesLoad-engaging elementsFrequency changerHigh speed control
The invention is applied to the technical field of electrical control, and provides a device and a method for controlling a slewing mechanism of a tower crane. The device for controlling the slewing mechanism of the tower crane is composed of a general frequency converter, an alternating-current brake circuit, a slewing motor, a direct-current brake circuit, a forward control circuit, a reversal control circuit, an intermediate-speed control circuit, a high-speed control circuit and a braking control circuit. At the moment of starting, the initial frequency of the general frequency converter is regulated and the speed reduction time is regulated when the output frequency of the general frequency converter is reduced, thus the torque of a tower body is released; under the control of the direct-current brake circuit, the swinging of a lifting arm and the torque of the tower body are released fully; meanwhile, the general frequency converter provides brake signals of the alternating-current brake circuit and brakes a slewing motor, and the lifting arm stops stably; and the comprehensive benefits of convenience in operation, long repairing and maintaining cycle and energy source conservation are realized by utilizing each function of the general frequency converter.
Owner:THE THIRD CONSTR OF CHINA CONSTR FIRST GROUP +1

Sensorless vector control system and method for permanent magnet synchronous motor

The invention provides a sensorless vector control system and method for a permanent magnet synchronous motor. The method comprises the steps of starting low-speed control, medium-high speed control and transition area control, wherein the starting of low-speed control respectively builds a low-speed rotor position observer and a low-speed rotor speed observer on the basis of a regression model; the medium-high speed control is realized through a traditional sliding-mode observer; the transition area control guarantees the smoothness of switching process by simultaneously considering two factors of rotating speed and rotor position error. By adopting the scheme provided by the invention, the reliable operation of the sensorless permanent magnet synchronous motor within the scope of full speed can be guaranteed, the sensorless permanent magnet synchronous motor is independent of a motor mathematical model in the low-speed modeling process, and the high-frequency signals are not required to be superposed; estimated results are not influenced by the parameters precision; the medium-high speed control is still realized through the sliding-mode observer; the characteristics of strong robustness and stable performance of the sliding-mode observer are retained. The switching process of two methods guarantees the smooth transition of the switching process by simultaneously considering the two factors of the rotating speed and the rotor position error.
Owner:SOUTHEAST UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products