47results about How to "Increase control frequency" patented technology

The invention discloses a module capacitor voltage sharing control method for a modular multilevel converter. The method comprises the following steps of sequencing all modules in each group according to the magnitudes of module voltage values, and searching for a maximum module voltage value Umax(i) and a minimum module voltage value Umin(i) in each group, wherein i is 1, 2, ..., N; performing voltage sharing processing on the module voltage value of each module according to the maximum module voltage value and the minimum module voltage value in each group to obtain an estimated module voltage value of each group, extracting M corresponding estimated module voltage values from the estimated module voltage values U(i, j) of all the groups according to current directions of bridge arms, extracting the corresponding modules from each group according to the M extracted estimated module voltage values and the current directions of the bridge arms, and putting the extracted modules in all the groups into use, wherein the number of the M estimated module voltage values in each group is equal to that of the extracted modules in the group. According to the method, the communication traffic of a controller can be effectively reduced, and meanwhile, module voltage can be shared.

The invention relates to a throttle control method and device, a power system and an unmanned aerial vehicle. The method comprises the following steps: an electronic governor receives throttle signalsthrough a serial communication interface; throttle control data is extracted from the throttle signal; a motor control signal is generated for controlling the operation of the motor according to thethrottle control data; and the motor control signal is transmitted to the motor. The throttle signal received by the serial communication interface is a digital signal. In the transmission process, the interference is small, unlike the analog signal is susceptible to resistance and anti-interference, tolerance and anti-interference and other kinds of analog signal disturbance, which results in inaccurate data. Moreover, the serial communication mode can adopt higher baud rate, shorten the throttle control cycle, achieve throttle high-speed control, and increase the frequency of control.

The invention belongs to the technical field of space-borne load application, and in particular relates to a method and system for compensating the angular momentum and moment of a space-borne large-inertia rotating load. To solve the problem that the existing compensation method cannot meet the load compensation requirements of large inertia and high speed, the system includes the first speed conversion unit, the balance wheel system, the second speed conversion unit and the turntable system; the method process is as follows: The speed is converted to the target speed of the balance wheel, and the balance wheel starts to accelerate to the target speed. The Hall signal output by the balance wheel is used to calculate the speed of the balance wheel in real time, and the real-time speed of the balance wheel is converted to the given speed of the turntable, and the reverse rotation is performed, thereby Ensure that the rotation speed of the turntable is matched and tracked with the rotation speed of the balance wheel in real time during the processes of acceleration, constant speed and deceleration to ensure the compensation effect of residual angular momentum and residual torque.

The invention discloses a control method of a foldable arm rest. The control method includes a detection step: detecting whether each arm section is in a completely closed state or not, a calculation step: ensuring that the arm section is in a completely folding state when the arm section is not in a completely closed state, obtaining the folding state of each arm section, working out the maximum distance L between the arm rest portion which is between the predetermined arm section and the tail end of the folding arm rest and a hinge point of the root end of the predetermined arm section according to the folding state of each arm section, and working out the allowable maximum angular velocity w when the predetermined arm section moves according to a predetermined linear velocity V and the maximum distance L, and a control step: controlling an actuating part which drives the predetermined arm section, and enabling the predetermined arm section to move at an angular velocity which is less than or equal to the maximum angular velocity w. The invention correspondingly discloses a control system of the foldable arm rest and engineering machinery. The control method and the control system has the advantages of being capable of improving folding speed of the foldable arm rest and working efficiency, easy to control, low in cost and good in stability.

The invention discloses a model predictive control method for a doubly-fed wind power generator that does not go off-grid. When the grid voltage drops, the rotor flux linkage predictive control method is adopted, and the optimal voltage vector is selected by predicting the rotor flux linkage to act on the rotor side transformation. The controller realizes the synchronous control of the rotor flux and the stator flux, and weakens the fault impact of the stator flux on the rotor flux, thereby reducing the rotor fault overcurrent. Compared with the model predictive control in the steady state, the control frequency of the rotor flux prediction method used in the grid fault is doubled, the response to the fault is faster, and the rotor current can be effectively controlled by 1.5-1.6 times in the fault state Within the rated current, the electromagnetic torque fluctuation is small, which improves the ability of the doubly-fed wind turbine not to go off-grid during a fault.