14 results about "Feedback control" patented technology

The invention discloses a non-road diesel engine combustor DPF regeneration temperature control method. According to the method, control over the regeneration temperature of a non-road diesel engine combustor DPF is completed by combining feedforward control and PID feedback control. The method has the advantages that closed-loop control is stable and feedforward control is fast. The control precision of the regeneration temperature of a DPF catalytic converter is improved. Under various diesel engine working conditions, the error of the actual temperature of an inlet of the DPF catalytic converter and the DPF target regeneration temperature can be controlled within 25 DEG C. Accordingly, a DPF system can conduct reliable regeneration temperature management under various working conditions.

A fabrication process produces markers for a magnetomechanical electronic article surveillance system. The marker includes a magnetomechanical element comprising one or more resonator strips of magnetostrictive amorphous metal alloy; a housing having a cavity sized and shaped to accommodate the resonator strips for free mechanical vibration therewithin; and a bias magnet to magnetically bias the magnetomechanical element. The process employs adaptive control of the cut length of the resonator strips, correction of the length being based on the deviation of the actual marker resonant frequency from a preselected, target marker frequency. Use of adaptive, feedback control advantageously results in a much tighter distribution of actual resonant frequencies. Also provided is a web-fed press for continuously producing such markers with adaptive control of the resonator strip length.

The invention relates to a gain control method of a distributed Raman fiber amplifier, which comprises the following steps of: firstly, acquiring the output power of a current pump and a signal light input power spectrum; then obtaining a gain error by the input power and a preset target gain, judging whether the gain error is larger than a preset threshold value or not, if so, executing the feedforward regulation on pump gain transient pre-control, or else, executing the feedback regulation on pump gain feedback control; when stepping into the feedforward regulation process, regulating the current pump and returning to the first step; and when stepping into the feedback regulation process, adjusting the current pump and returning to the first step. The invention also relates to a gain control device of the distributed Raman fiber amplifier. The gain control method and device of the distributed Raman fiber amplifier have the advantages of fast regulation speed, difficult divergence in the process, convergence time reduction and system performance improvement.

The invention discloses a main circuit of a three-phase four-wire DC/AC convertor and a control method thereof. The main circuit comprises two power semiconductor switches G1 and G2, two diodes D1 and D2, a capacitance branch and an inductor L1, wherein the two power semiconductor switches G1 and G2 are connected with a bridge arm with midpoint drifting control in series from top to bottom; the two diodes D1 and D2 are connected with power semiconductor switches in parallel reversedly; the capacitance branch is connected with the bridge arm with the midpoint drifting control in parallel; the capacitance branch is formed by two series capacitors C1 and C2; and one end of the inductor L1 is connected with the point of common coupling (PCC) of the two semiconductor switches G1 and G2, and the other end of the inductor L1 is connected with the PCC of the two series capacitors C1 and C2, as well as a midcourt line in the three-phase four-wire convertor is led out, namely an N line. In the invention, the bridge arm in a midpoint control circuit and three bridges of a three-phase convertor can be controlled respectively and independently, thus realizing decoupling control of a three-phase four-bridge arm convertor. Under the condition of three phase imbalance, simple voltage current feedback control or proportional-integral (PI) control is used to control the midpoint, so that the midpoint drifting control can be finished.

The invention relates to a method and a device for generating a true random number. The device comprises a high frequency oscillator, an initial seed number generation unit, an error diffusion calculation unit, a linear feedback unit, a control unit and a random number output unit, wherein the output end of the high frequency oscillator is connected with the input end of the initial seed number generation unit; the output end of the initial seed number generation unit is connected with the input end of the error diffusion calculation unit; the output end of the error diffusion calculation unit is connected with the linear feedback unit; the output end of the linear feedback unit is connected with the control unit; and the control unit is connected with the random number output unit. The device achieves a metastable state circuit only by using general logic hardware, so the hardware structure is simplified; one-time-pad is realized by storing an initial seed number in a cache reset at each time; judgment and feedback control are realized by using a generator polynomial; and a secure hash algorithm is realized by using an error diffusion process, therefore, an effect that the random number is difficult to copy or forecast is achieved.

A damping control device for an electric vehicle is having a continuously variable transmission between a motor and left and right front wheels. The damping control device drive system includes a feedback control unit, which suppresses a vibration accompanying a disturbance in the rotational speed of the motor, and an operation determination unit, which determines whether or not an absolute value of a second-order differential of the transmission ratio is equal to, or greater than, a predetermined value, wherein when the absolute value of the second-order differential of the transmission ratio is equal to, or greater than, the predetermined value. The feedback control unit performs control of the output torque of the motor whereby a compensation torque component for suppressing a vibration accompanying a gear shift is subtracted from a compensation torque.

The invention provides a power proportion regulating device and method and an inductance-coupling plasma generator, belonging to the field of power regulation, which solves the problem of high cost of the traditional power proportion regulating technology. The power proportion regulating device provided by the invention comprises an input end, a plurality of in-parallel output ends, a power regulating unit and a feedback controlling unit, wherein the feedback controlling unit is used for controlling the power regulating unit so as to enable output powers of the plurality of output ends to satisfy with a preset proportional relation. The inductance-coupling plasma generator provided by the invention comprises the power proportion regulating device. The power proportion regulating method provided by the invention comprises the step of controlling the power regulating unit according to the preset proportional relation between actual output powers and the output powers of the output ends.

The object of the present invention is to obtain a contact pressure control device capable of carrying out feedback control enduring a practical use by inventing a pressure detecting means and the employment structure of the same. The contact pressure control device of the take-up winder comprises a bobbin holder 5, a contact pressure roller 11 contacted against the bobbin B set on the bobbin holder 5, a slide supporting mechanism (s) for supporting the contact pressure roller elevating or descending to the machine main body 2 , and a contact pressure cylinder 13 freely adjusting the contact pressure of the contact pressure roller 11 and the bobbin holder 5. Moreover, a load cell 16 is provided directly below one contact pressure cylinder 13 located between a pair of slide supporting mechanisms (s), (s). Furthermore, a print circuit board for controlling is provided for controlling the contact pressure cylinder 13 based on the detected value of the load cell 16 so that the contact pressure is to be maintained at a designated value.

The invention discloses a system and a method for monitoring the optical fiber fuse effect. The system comprises a laser module, a linear swept source module, a light power injecting module, a Mach Zehnder interferometer module, a photoelectric detecting and data acquiring module and a swept source feedback controlling module, wherein swept light generated by the linear swept source module enters the Mach Zehnder interferometer module and is divided into probe light and reference light; a light signal generated by the laser module and the probe light are coupled in the light power injecting module and then enters a to be monitored optical fiber link, and signal light returned to the light power injecting module from the optical fiber link enters the Mach Zehnder interferometer module for interference beating with the adjusted reference light, and is input into the photoelectric detecting and data acquiring module; the feedback controlling module is used for controlling the laser module; the data acquiring module is used for performing later data processing, judging the occurrence of the optical fiber fuse effect and obtaining the position of a fault point through calculation. By means of the system and the method, monitoring is rapid and accurate, and the length and the position of a damaged optical fiber can be accurately determined.

The embodiment of the invention discloses a fingerprint processing device, which comprises a protection layer, an adhesive, a fingerprint collection chip, a collector, a bucking circuit 1, a PGA 1, a bucking circuit 2, a PGA 2, an ADC and a control chip, wherein the collector is used for amplifying and converting capacitance signals of a fingerprint capacitor Cf to reduce noise influences from a subsequent circuit; the bucking circuit 1 is used for carrying out secondary precise bucking on offset noise; the PGA 1 is used for amplifying output signals of the bucking circuit 1 and inputting the amplified signals to the bucking circuit 2, and the PGA 1 adopts high gains to reduce design requirements of the subsequent circuit; the bucking circuit 2 is used for carrying out secondary precise bucking on the offset noise; the PGA 2 is used for properly adjusting the signal amplitude; the ADC is used for outputting digital signals to the control chip; and the control chip is used for carrying out feedback control based on the digital signals. According to the embodiment of the invention, the resolution of signals of a valley and a ridge of a user finger is improved when the user fingerprint is collected, and the offset noise generated during the signal processing process is bucked.

The invention provides an explodent elimination circuit. The explodent elimination circuit is used for explodent elimination during power on and power off of an output node of an audio digital-to-analog converter, and comprises four resistors, three positive channel metal oxide semiconductor (PMOS) transistors, two negative channel metal oxide semiconductor (NMOS) transistors, a comparator, a pull-up current source, a pull-down current source and a control logic module, wherein the pull-up current source and the pull-down current source slowly charge the output node or provide a discharge path and can effectively eliminate the explodent of the output node during power on and power off; and the adjustable voltage rise speed and voltage drop speed of the output node are ensured by a current source structure and feedback control. The invention has the characteristics that: the explodent elimination circuit can be widely applied to a power amplifier at the rear end of a single-bit audio digital-to-analog converter, a multi-bit audio digital-to-analog converter or the audio digital-to-analog converter, and can effectively eliminate the explodent caused by abrupt power on or power off of the output node of the audio digital-to-analog converter; the voltage rise time and the voltage drop time of the output node are controllable, complicated control logics are unnecessary, and the power consumption is low.

The invention discloses a visual end feedback control method based on 3D printing, and the visual end feedback control method based on 3D printing includes the following steps that a model is input toa 3D printing robot arm; visual inspection printing model is carried out; compared with an original model of a robot arm, difference is produced and sent to PLC; and finally, the PLC moves the chassis to compensate and feeds back to the robot arm. The invention provides a novel feedback control method and system for 3D printing, and the novel feedback control method for 3D printing can significantly improve the precision of 3D printing. The visual end feedback control method based on 3D printing feeds back to the vision and the robot arm through a method of low disk movement and corrects theprinting position error in real time.