112 results about "Dual loop control" patented technology

Disclosed is a repetitive dual-closed-loop control method for an LCL type grid-connected inverter. According to the method, the difference value between a given grid-connected current and an actual grid-connected current is used as input of a repetitive controller; the sum of the output of the repetitive controller and the given grid-connected current is used as a given value of an internal loop; the difference value between the given value of an internal loop controller and the actual grid-connected current is used as the input of an internal loop PI controller; the output of a power grid voltage which passes through a feedforward transfer function is used as the output of a power grid voltage feedforward link; and the output of the internal loop PI controller and the output of the feedforward link are added together to be used as a control signal for switching on and switching off an inverter bridge switching tube in an inversion link. According to the repetitive dual-closed-loop control method, the single grid-side current feedback is adopted, so that the dual-loop control is realized, and the cost is lowered; meanwhile, due to the PI controller and the repetitive controller which are connected in series, the decoupling of the controllers is realized; and the grid-connected system has higher steady-state control precision, higher dynamic response speed and higher robustness.

The invention discloses a one-hydraulic-motor double-loop control system and belongs to the technical field of hydraulic transmission control. The one-hydraulic-motor double-loop control system comprises a hydraulic motor, an active control loop, a passive control loop, a hydraulic pump, an energy accumulator and an oil tank. The hydraulic motor is of a unique flow allocation structure and is provided with four oil inflow and outflow ports, the active control loop and the passive control loop work independently and control the hydraulic motor, the hydraulic motor can be driven by the active control loop and the passive control loop simultaneously or driven by one of the active control loop and the passive control loop independently, the braking kinetic energy and potential energy of loads can be stored in the energy accumulator, and therefore energy can be recycled. According to the one-hydraulic-motor double-loop control system, one hydraulic motor is adopted, so that the driving requirements of different working conditions and different loads are satisfied at the same time and the system has the advantages of being simple in structure, high in system reliability, capable of saving energy and efficient.

Systems and methods for performing semiconductor laser annealing using dual loop control are disclosed. The first control loop operates at a first frequency and controls the output of the laser and controls the 1 / f laser noise. The second control loop also controls the amount of output power in the laser and operates at second frequency lower than the first frequency. The second control loop measures the thermal emission of the wafer over an area the size of one or more die so that within-die emissivity variations are average out when determining the measured annealing temperature. The measured annealing temperature and an annealing temperature set point are used to generate the control signal for the second control loop.

A fault-tolerant control system and method for variable-speed variable-pitch wind turbines with an inverter-fed generator. When generator faults are detected, the generator torque and / or flux is limited to prevent propagation of the faults and possible failure and shutdown of the generator. The control system and method improves on two-loop control methods for variable-speed variable-pitch wind turbines and provides improved power delivery under fault conditions.