35 results about "Feedforward systems" patented technology

An objective is to obtain a high robust position controller and a controlling method therefor, with respect to their technique in which control gain, in order to prevent an overshoot due to frictions, is most suitably adjusted. The position controller having a feedforward system includes: a friction-coefficient-estimated-value setting unit for setting arbitrary friction-coefficient-estimated-values; an overshoot-prevention-gain calculator for determining speed-integral-term feedforward gain, based on estimated friction-coefficient values set by the friction-coefficient-estimated-value setting unit; and a speed feedforward multiplying unit for calculating the product of the speed-integral-term feedforward gain multiplied by a feedforward command value that is based on a positional command; the multiplication product from the speed feedforward multiplying unit being used to reduce the feedforward term.

A noise-canceling headphone that cancels external noise with a feedforward system includes a driver unit disposed in a housing, a microphone unit that is outwardly disposed in the housing and collects the external noise, and canceling signal generator that generates a noise-canceling signal having a phase opposite to the noise entering through the headphone. The noise-canceling headphone includes an error detecting microphone unit that detects error noise uncanceled by the feedforward system, and error noise-canceling signal generator that generates an error correction signal to cancel the error noise with a feedback system.

The invention discloses a design of a TCR static var compensator (SVC) provided with a T-shaped active power filter (APF) and a control method thereof. The var compensator adopts a hybrid SVC composed of the T-shaped active power filter and an SVC and is connected with a power factor corrector of a small-sized voltage source inverter type (PFC-VSI). A harmonic compensation control loop of the APF part in the device consists of two parts, namely, a direct feedback control loop and a feedforward system; the active power filter part of the system consists of a capacitor Cf, an inductor Lf and an APF-VSI connected with the inductor Lf in parallel. The TCR part is mainly applied in absorbing harmonic current and adjusting reactive power. For the T-shaped active power filter is adopted, the inductor Lt of the TCR branch has high resistance during ultraharmonics and can naturally filter part ultraharmonics. Compared with the prior harmonic filter different from the harmonic filter provided by the invention which works together with the voltage source inverter of low bandwidth, and therefore the control of the system is simpler than common harmonic filters and not affected by the inherent delay of one period when DSP is executed.

An objective is to obtain a high robust position controller and a controlling method therefor, with respect to their technique in which control gain, in order to prevent an overshoot due to frictions, is most suitably adjusted. The position controller having a feedforward system includes: a friction-coefficient-estimated-value setting unit for setting arbitrary friction-coefficient-estimated-values; an overshoot-prevention-gain calculator for determining speed-integral-term feedforward gain, based on estimated friction-coefficient values set by the friction-coefficient-estimated-value setting unit; and a speed feedforward multiplying unit for calculating the product of the speed-integral-term feedforward gain multiplied by a feedforward command value that is based on a positional command; the multiplication product from the speed feedforward multiplying unit being used to reduce the feedforward term.

A receiver for an optical communications system which corrects distortion of a received signal. A clock recovery system utilising a feedback and feedforward system are provided. The feedback loop comprises a phase detector and a clock source, while the feedforward loop comprises the phase detector and a delay element for delaying the output of distortion correction system. The feedback loop has a significantly lower bandwidth than the feedforward path. There are also provided methods of optimising tap weights and of acquiring initial tap weights.

A system for a gas turbine includes a control system comprising a processor. The processor is configured to receive a signal indicating spray intercooling fluid demand of the gas turbine. The processor is configured to determine a rate of change of the spray intercooling fluid demand. The processor is configured to control flow of a nitrogen oxide (NOX) minimization fluid that reduces NOX emissions from the gas turbine based at least in part on the rate of change of the spray intercooling fluid demand.

The invention provides motor controller capable of improving instruction traceability; the motor controller (100) comprises the following elements: a differentiator differentialing externally inputted speed instruction; a torque feedforward portion (112) used for generating a first torque indication for the feedforward system according to the differential speed instruction; a speed control portion (114) used for generating a second torque indication according to deviation between the externally inputted speed indication and the speed feedback; a torque indication filter (116) used for preventing machinery resonance and encoder quantization wave of the second torque indication; an addition operation point used for carrying out addition operation for the first torque indication and the second torque indication outputted from the torque indication filter (116), thus generating a third torque indication; a torque control portion (118) using the third torque indication to control the motor motions.

The invention discloses a subcritical unit coordination prediction function control algorithm based on a leading disturbance model. The conventional PID control system can not consider both the load quickness and the pressure stability, and the quality of a coordination control system needs to be improved. The prediction function control is applied to a pressure closed loop of the subcritical unit coordination control system, a prediction function control system is formed, and the pressure closed loop has a delay inertial link; the load closed loop of the subcritical unit coordination control system adopts PID control, and a load instruction adopts a datum line plus differential mode for a coal quantity feedforward system; an actual turbine control valve instruction serves as a disturbance signal source, and the optimal control law is acquired according to a prediction model of the prediction function control system; and simplification is carried out on the basis of the optimal control law, and a simplified optimal control law is obtained. The control quality of the subcritical unit coordination control system is improved, and both the load quickness and the pressure stability can be considered.

The invention discloses a water hydraulic motor speed control system and method. The present invention utilizes fuzzy control to overcome the defects of low control precision of the traditional control method and cannot adapt to the multi-variable and non-linear defects of the water hydraulic system; utilizes target rotational speed feedforward and system total volume efficiency feedback to compensate the rotational speed fluctuation of the water hydraulic motor in advance; The difference between the theoretical speed and the actual speed of the servo motor is fed back, forming a local small closed loop in the control of the speed of the servo motor, improving the accuracy of the speed control of the servo motor; based on the multi-resolution analysis theory, the interference components in the flow signal are analyzed The signal is stripped, and then the signal is reconstructed; the wavelet transform is performed on the rotational speed signal to reduce or eliminate the quantization error in the rotational speed information. The invention has high control precision for the rotational speed of the water hydraulic motor, fast response speed, strong anti-disturbance ability, and smooth output of the rotational speed of the water hydraulic motor.

The invention provides motor controller capable of improving instruction traceability; the motor controller (100) comprises the following elements: a differentiator differentialing externally inputted speed instruction; a torque feedforward portion (112) used for generating a first torque indication for the feedforward system according to the differential speed instruction; a speed control portion (114) used for generating a second torque indication according to deviation between the externally inputted speed indication and the speed feedback; a torque indication filter (116) used for preventing machinery resonance and encoder quantization wave of the second torque indication; an addition operation point used for carrying out addition operation for the first torque indication and the second torque indication outputted from the torque indication filter (116), thus generating a third torque indication; a torque control portion (118) using the third torque indication to control the motor motions.

A system for a gas turbine includes a control system comprising a processor. The processor is configured to receive a signal indicating spray intercooling fluid demand of the gas turbine. The processor is configured to determine a rate of change of the spray intercooling fluid demand. The processor is configured to control flow of a nitrogen oxide (NO.sub.X) minimization fluid that reduces NO.sub.X emissions from the gas turbine based at least in part on the rate of change of the spray intercooling fluid demand.

The invention is a system (1) that simulates a decision process in a mammalian brain with respect to a motion characteristic relating to a visually observed body posture of a body by means of a simulated visual path comprising an interface towards a simulated neuronal structure, the system includes an interface that converts at least luminescence information of the observed body into an optical flow data stream that delivers information relating to the visually observed body and that can be processed in the simulated neuron structure, the system being a feed-forward system that can be coupled to the simulated neuron structure. And from the visual observation that the decision comprises hierarchically: the simulated visual path and its interface (3, 3L, 3R); a simulated local motion direction detection neuron structure (4, 4L, 4R) for detecting the motion direction by means of a receptive field; a simulated opposition motion detection neuron structure (5, 5L, 5R) for detecting opposition motion at least relating to expansion and contraction; a simulated complex pattern detection neuron structure (6, 6L, 6R) for globally detecting an optical flow pattern over the entire visual observation and according to the evolution of the entire visual observation during the time, the detectable pattern being a prototype pattern; and a simulated motion pattern detection neuron structure (7, 7LR) for detecting a motion pattern and providing a decision regarding a motion characteristic. According to the invention, the neurons of the simulated motion pattern detection neuron structure (7, 7LR) comprise a forgetting ability that is a function of the delay and for each neuron an activity of the neuron.

The invention discloses a design of a TCR static var compensator (SVC) provided with a T-shaped active power filter (APF) and a control method thereof. The var compensator adopts a hybrid SVC composed of the T-shaped active power filter and an SVC and is connected with a power factor corrector of a small-sized voltage source inverter type (PFC-VSI). A harmonic compensation control loop of the APFpart in the device consists of two parts, namely, a direct feedback control loop and a feedforward system; the active power filter part of the system consists of a capacitor Cf, an inductor Lf and anAPF-VSI connected with the inductor Lf in parallel. The TCR part is mainly applied in absorbing harmonic current and adjusting reactive power. For the T-shaped active power filter is adopted, the inductor Lt of the TCR branch has high resistance during ultraharmonics and can naturally filter part ultraharmonics. Compared with the prior harmonic filter different from the harmonic filter provided by the invention which works together with the voltage source inverter of low bandwidth, and therefore the control of the system is simpler than common harmonic filters and not affected by the inherentdelay of one period when DSP is executed.

A receiver for an optical communications system which corrects distortion of a received signal. A clock recovery system utilising a feedback and feedforward system are provided. The feedback loop comprises a phase detector and a clock source, while the feedforward loop comprises the phase detector and a delay element for delaying the output of distortion correction system. The feedback loop has a significantly lower bandwidth than the feedforward path. There are also provided methods of optimising tap weights and of acquiring initial tap weights.

The present technology relates to a gain control circuit, a communication device, an electronic appliance, and a gain control method which aim to provide a technology capable of suppressing intermodulation distortion. The gain control circuit includes a first amplifier for amplifying an input signal, and a signal determination unit for determining an input signal to be input to the first amplifier, and controlling an amplification factor of the first amplifier based on the determination result. The communication device includes a first amplifier for amplifying a received signal, a receiving unit for performing a receiving process based on a signal output from the first amplifier, and a signal determination unit for determining a received signal to be input to the first amplifier, and controlling the amplification factor of the first amplifier based on the determination result. In the gain control method, an input signal to be input to a first amplifier for amplifying an input signal is determined, and the amplification factor of the first amplifier is controlled by a feed forward system based on the determination result.

Provided is an AC / DC hybrid micro-grid grid connection robust control method taking uncertainty into consideration. The method includes the following steps: on the basis of the superposition theorem,establishing an AC / DC hybrid micro-grid grid connection mathematical model and a feed-forward system mathematical model in accordance with an AC / DC hybrid micro-grid grid connection topological structure; independently controlling a DC sub-micro-grid and providing a reference voltage to a filter capacitor in an AC / DC hybrid micro-grid; and constructing an AC / DC hybrid micro-grid grid connection robust controller and AC / DC hybrid micro-grid grid connection is achieved, so the robust performance of the AC / DC hybrid micro-grid is improved. The method of the invention avoids overcurrents in grid connection points during AC / DC hybrid micro-grid grid connection, realizes seamless switching, and enables AC / DC hybrid microgrids still to be normally connected in a condition of certain parameter perturbation.