40 results about "Reference tracking" patented technology

An exemplary electrical converter includes a plurality of semiconductor switches. The electrical converter is configured for generating a two-level or multi-level output voltage from an input voltage by switching the plurality of semiconductor switches. A method for controlling the electrical converter includes receiving a reference electrical quantity (iS*) and an actual electrical quantity (iS), determining a sequence of future electrical quantities of the electrical converter from the actual electrical quantity, determining a maximal cost value based on the sequence of future electrical quantities, and iteratively determining an optimal switching sequence for the electrical converter. A switching sequence includes a sequence of future switching states for the semiconductor switches of the electrical converter. The method also includes selecting the first switching state of the optimal switching sequence as the next switching state (u) to be applied to the semiconductor switches of the electrical converter.

The system described herein may track references to a shared object by concurrently executing threads using a reference tracking data structure that includes an owner field and an array of byte-addressable per-thread entries, each including a per-thread reference counter and a per-thread counter lock. Slotted threads assigned to a given array entry may increment or decrement the per-thread reference counter in that entry in response to referencing or dereferencing the shared object. Unslotted threads may increment or decrement a shared unslotted reference counter. A thread may update the data structure and / or examine it to determine whether the number of references to the shared object is zero or non-zero using a blocking-optimistic or a non-blocking mechanism. A checking thread may acquire ownership of the data structure, obtain an instantaneous snapshot of all counters, and return a value indicating whether the number of references to the shared object is zero or non-zero.

A sub-pixel-level target tracking method based on feature matching, including: selecting the tracking point of the first frame image as a reference tracking point in the continuously transmitted images; respectively processing the first frame image and the Nth frame image to obtain the first frame image The feature vector of a frame image and the feature vector of the Nth frame image, N is a natural number greater than 1; the first frame image is matched with the feature vector of the Nth frame image to obtain a pair of feature points; the pair of feature points is estimated to obtain Transformation matrix, perform dot multiplication between the transformation matrix and the reference tracking point to obtain a new tracking point, and complete the update of the tracking point. The sub-pixel-level target tracking method based on feature matching proposed by the present invention can track a point in the target with high precision, and is robust when there are obvious changes in the image tracking point area; at the same time, the method is simple to calculate and can be parallelized High precision is beneficial for accelerated calculations, and can be widely used in high-speed and high-precision real-time tracking photoelectric countermeasure systems.

The invention discloses a single-phase self-excitation wind power generation system. A single-phase self-excitation generator with adjustable excitation consists of a three-phase squirrel-cage motor, a capacitor with fixed excitation and a capacitor with adjustable excitation; the capacitor with adjustable excitation comprises a fixed capacitive value and an adjustable capacitive value, and the capacitive value adjustment is realized by IGBT duty ratio regulation and control; an alternating current load is connected with a bidirectional PWM converter in parallel, and coupled with an electric generator stator winding; an adjusting mechanism for adjusting voltage frequency of the electric generator is formed by a bidirectional converter and a storage battery; when the voltage control saturation of the capacitor with adjustable excitation is limited, the adjusting mechanism cooperatively controls the port voltage of the electric generator, and an active and reactive current reference tracking control policy is completed by adopting a 90-degree phase shift based single-phase voltage and current decoupling policy; and the active current reference is implemented by a frequency setting PI tracking controller, while the reactive current reference is implemented by a voltage amplitude PI tracking controller, and the reactive current reference value is the value, exceeding the saturation limited part, of the PI control output.