118 results about "Cascade control system" patented technology

The invention discloses a henhouse micro climatic environment intelligent control system based on a wireless sensor network. The henhouse micro climatic environment intelligent control system is characterized by comprising a henhouse micro climatic environment parameter acquisition and control platform, a henhouse micro climate farming environment cascade control system based on a DRNN PID neural network, and an expert system based on economic optimal reasoning and for setting ideal values of controlled henhouse micro climatic environment parameters. According to the invention, the henhouse micro climatic environment intelligent control system based on the wireless sensor network is designed through the characteristics of multiple parameter variables, nonlinearity, strong coupling and large inertia of conventional henhouse farming micro climatic environment.

The invention provides a tension stability control system for film winding conveyance, which comprises a feeding roller, paired driving rollers, paired driven rollers, a tension roller and a tension controller, wherein the feeding roller is used for uncoiling a coiled flexible film, the paired driving rollers are used for drawing the film, the paired driven rollers are used for assisting the paired driving rollers in drawing the film under control of the tension controller and are used for keeping tension stable, the tension roller is provided with a tension sensor for detecting tension during conveyance of the film, and the tension controller is used for performing tension closed-loop control according to tension acquired by the tension sensor. Output signals of closed-loop control serve as compensation of operation planning commands of a driving motor for the paired driven rollers, and further the rotation speed of the paired driven rollers is controlled to ensure stability of the tension. By the aid of a cascade control system formed by the tension roller, tension amplification filtering and driving compensation, low tension during flexible film conveyance can be effectively controlled, control precision is high, and the tension stability control system is applicable to low-tension conveyance of ultrathin and flexible hetero-structure films.

Provided is a dynamic compensation method of an attemperation water impact leading steam temperature measuring point in a boiler steam temperature control system. According to the method, an attemperation water impact leading steam temperature measuring point correction factor on-line computation module is arranged in the overheating and reheating steam temperature cascade control system of a power station boiler, the correction factor of the attemperation water impact leading steam temperature measuring point is computed on line through the module, the difference between a steam temperature set value and a controlled steam temperature feedback value is divided by the correction factor to compensate changing of inertia zone object gain, output of an auxiliary adjuster is multiplied by the correction factor to compensate changing of leading zone object gain, and accordingly dynamic compensation of the attemperation water impact leading steam temperature measuring point is achieved. The method achieves dynamic compensation of the attemperation water impact leading steam temperature measuring point in the steam temperature control system and has the advantages of being good in compensation effect, field conduction is convenient, control effect is good, control quality of the overheating and reheating steam temperature cascade control system of the power station boiler can be guaranteed, and safety and economy of operation of the power station boiler are improved.

Cascade control logic for use in a switch or other network unit that can be used in a cascaded stack can maintain normally a point-to-point half-duplex connection for control data with each of the next preceding and next succeeding units in the cascade. Each cascade logic device is organised so that for one direction, conveniently called the up direction, a device is a master and in the other direction the device is a slave in respect of the control path. A control device will generate master control frames in the up direction and deliver slave control frames in the down direction. The control device is organised so that in the absence of reception of valid control frames on a control link control data which would otherwise be sent out on that link is looped back within the control device. In this manner the control device can maintain under normal circumstances two virtual control channels which can ‘self-heal’ notwithstanding the failure or powering-down of a unit in the cascade.

Status information represented by the control frames can be used to control a switching engine to provide self healing of the data path in the cascade.

The invention discloses a fattening pig house environment regulation and control system and method. The system comprises a detection unit, a control unit and a monitoring center. The detection unit detects temperature, humidity, air flow and ammonia of a fattening pig house. The control unit controls control equipment through utilization of PI secondary regulators. The monitoring center circularlyreads temperature, humidity, air flow and ammonia parameters of a fattening pig house environment collected by the detection unit, designs a single-neuron adaptive PSD controller+ a neuron decouplingcompensator to form a fattening pig house environment master regulator for the temperature, the humidity, the air flow and the ammonia, and realizes effective control over the temperature, humidity,air flow and ammonia of the fattening pig house environment. The detection unit detects the temperature, humidity, air flow and ammonia of the fattening pig house through utilization of sensors. Inputof the PI secondary regulators of the control unit comes from output of the neuron decoupling compensator of the monitoring center, thereby forming a multi-cascade control system of the master and secondary regulators.

The invention relates to a coal water slurry gasification process DMC-PID multivariable control method, concretely a coal water slurry gasification process multivariable control method by employing a dynamic matrix control and proportion-integral-differential control cascade control system (hereinafter referred to as a DMC-PID control method). A coal water slurry gasification process control system is characterized in that charging flow control mainly comprises coal water slurry flow cascade control and oxygen coal ratio cascade control; the core of vaporizer control is gasifier hearth temperature control; quenching chamber control mainly comprises quenching water flow and raw gas temperature cascade control. In the adjustable range of manipulated variables, the DMC-PID control method can control coal gasification process main manipulated variables in an industrial requirement range, thereby effectively solving the problems such as multivariable coupling between a gasification temperature and a synthetic gas yield in a coal water slurry gasification process.

The invention provides a compensation method of random time-delay of the external forward and internal feedback paths of a network cascade control system, belonging to the technical field of the network control system. The method uses the actual external forward network path nodes of the network cascade control system and adopts the network data transmission process between the internal feedback network path nodes to replace the compensation model of network time-delay between the nodes, avoid the measurement, observation, estimation or identification of the network data transmission random time-delay between the nodes and remove the synchronization requirement on the node clock signal. By adopting the method, the influence of the random network time-delay on the system stability can be reduced and the performance quality of system control can be imprved. The method of the invention is suitable for the dynamic compensation and control of random network time-delay when the mathematicalmodels of the main controlled object and auxiliary controlled object are known and the network only exists in the external forward and internal feedback paths of the cascade control system.

By aiming at characteristics of dissolved oxygen parameters of aquaculture pond environment such as large working condition area, non-linear variety, and great inertia, and unbalance pond environment dissolved oxygen distribution, the invention discloses an aquaculture pond dissolved oxygen control system of a wireless sensor network. The aquaculture pond dissolved oxygen control system is constituted by an aquaculture pond environment dissolved oxygen acquisition and control platform, a pond dissolved oxygen cascade control system based on a composite controller, and an expert system of setting aquaculture pond environment dissolved oxygen based on economic optimal reasoning. The aquaculture pond dissolved oxygen control system is advantageous in that the control stability and the control precision of the aquaculture pond dissolved oxygen are improved, and important popularization and application values are provided for the economic benefit of the aquaculture pond.

An airship dynamic adaptive harness is provided to stabilize airships and particularly a tethered aerostat in high winds and atmospheric changes. A novel adaptive device accommodates the supply of a lift gas and simultaneously controls opposing cables in a tethered harness with a cascade control system that provides an immediate and particularly the dynamic control of roll, yaw and particularly the pitch of the aerostat in response to real time environmental flight conditions and impart stability to the airship in high winds using a stability zone geometric suspension control system and enhance the duration of in flight missions. A lifting gas replenishment system and particularly a ground based lifting gas replenishment system adds long duration deployment to the dynamic adaptability to high wind conditions for long term deployment.

The invention discloses a temperature cascade control system of a casting holding furnace and a control method of the temperature cascade control system. The temperature cascade control system comprises the holding furnace, a furnace gas thermocouple, a metal liquid thermocouple, a combustion-supporting air adjusting valve, a wind-control air proportional valve, a combustion-supporting draught fan, a natural gas output port, a nozzle and a PLC. The nozzle is installed on the holding furnace and connected with the combustion-supporting draught fan through a pipe to form a first pipeline, and the nozzle is connected with the natural gas output port through a pipe to form a second pipeline. The wind-control air proportional valve is connected between the first pipeline and the second pipeline, and a combustion-supporting air adjusting valve is arranged between the wind-control air proportional valve and the combustion-supporting draught fan. The furnace gas thermocouple and the metal liquid thermocouple are connected with the input end of the PLC, and the output end of the PLC is connected with the combustion-supporting air adjusting valve. The temperature cascade control system is simple and reliable in control, collecting of the temperature of the furnace gas and the temperature of the metal liquid and controlling over the combustion-supporting air adjusting valve are automatically finished, the whole process is controlled in a closed-loop mode, the oxidation burning loss of the metal liquid in the furnace is effectively reduced, and the production cost is saved.

The invention discloses a cascade control system and method of a flexible robot based on time-varying interference compensation. The cascade control system includes a direct current motor side position controller, an extended state observer based on a direct current motor model, a mechanical arm side position controller, an extended state observer based on a mechanical arm model, a direct currentmotor side position sensor, a mechanical arm side position sensor, a direct current motor, flexible joints and a mechanical arm. The mechanical arm side position controller comprises feedforward compensation control based on interference estimation and feedback control based on state estimation; the direct current motor side position controller includes feedforward compensation control based on interference estimation and feedback control based on state estimation. Compared with a traditional cascade proportional-differential control method, the cascade control system and a method of a flexible robot based on time-varying interference compensation are simple in design and implementation, strong in anti-interference ability, and the application requirements of a position tracking system ofa single-joint flexible mechanical arm can be meet.

The invention relates to a multi-stage evaporation and air-vapour hybrid system and method thereof, comprising a multi-stage evaporation tower, a cascade control system for feeding a liquid charging stock, a heater and three nozzles. The multi-stage evaporation tower comprises a tower body and a tower base divided into three segments with two dividing tower plates. The tower body is provided with an air-vapour outlet, a feeding inlet, an air-vapour inlet, a liquid outlet and a leakage fluid drain. The method provided by the invention comprises the following steps: the liquid charging stock is shunted and regulated through the cascade control system, and then fed into an upper tower body of the multi-stage evaporation tower and the heater, and a liquid mixture is heated in the heater. The air is loaded into the nozzle, the liquid mixture is mixed and evaporated in the heater, then air-vapour mixture is fed into the multi-stage evaporation tower. The air-vapour mixture product is discharged from the top and a residual liquid is further discharged. The invention realizes multi-stage evaporation and condensation of the mixture liquid through a plurality of nozzles and multi-stage evaporation tower system, and control is simple.

The invention provides a time-varying network time delay compensation method of a forward access of a networked cascade control system (NCCS), belonging to the technical field of networked control system. In the method, a network data transmission process among forward access nodes is used instead of a network time delay compensation model among the forward access nodes so as to avoid measurement, observation, estimation or recognition of time-varying time delay when network data among the real forward access nodes are transmitted and prevent the requirements of synchronization of node clock signals. By using the method, the influence of the time-varying network time delay on the stability of a system can be reduced and the control performance quality of the system can be improved. The method is suitable for dynamic compensation and control of the time-varying network time delay when a network only exists in the forward access of the networked cascade control system under the condition that a mathematical model of a main controlled object is known or uncertainly known, a mathematical model of a vice controlled object is known, and certain interference signals exist in the system.

The invention provides a control system for improving acrylonitrile production stability. The system includes a recovery tower sensitive plate temperature controller, a recovery tower, a reboiler flow control loop, and a recovery tower feed flow control loop. The output ends of the reboiler flow control loop and the recovery tower flow control loop are connected to the input end of the recovery tower. The sensitive plate temperature controller and the reboiler flow control loop form a cascade closed loop. A temperature set value of the sensitive plate temperature controller and a measured temperature value of the recovery tower are output to a reboiler flow controller. The assemblies and the loops are controlled by automatic valves. The recovery tower flow control circuit is provided with a flow controller. The sensitive plate temperature controller and reboiler flow cascade closed loop is equipped with a calculation module. The feed amount of the recovery tower is input as a feedforward into the calculation module together with an output value of the sensitive plate temperature controller, thus forming a feedforward cascade control system. The control method is a method for realizing improvement of product acrylonitrile stability. The system and the method can improve the stability of acrylonitrile production.

The invention provides a PID (Proportion Integration Differentiation) control parameter self-correcting method based on a closed-loop step response cascade loop, and belongs to the technical field ofcascade system controller parameter setting. According to the method, closed-loop step response data of a control loop is collected, and then a series of off-line operations are carried out accordingto the closed-loop step response data to obtain a set controller parameter value, so that the condition that the normal operation of the control system needs to be interrupted when the existing controller parameter setting method corrects the controller parameters through multiple times of external excitation is avoided; and moreover, in the controller parameter derivation process, the condition that interference exists in an auxiliary loop is considered, and the parameters of an auxiliary controller are corrected by utilizing a direct analysis design principle, so that the anti-interference performance and the stability of the control loop are improved. Tests in an actual industrial application rectifying tower stripping section temperature value control system show that the method can obviously reduce the overshoot phenomenon of a cascade control system, and the fluctuation range of the control system is obviously reduced when interference is generated.

The invention discloses a configuration design method of a switching control system. The configuration design method is based on a DCS (distributed control system) control platform, and includes that a secondary desuperheater is adopted for temperature control, a set value of a main control loop of primary desuperheating water spray is an inlet temperature design value of a secondary superheater, input of an auxiliary control loop is a desuperheater outlet temperature of a primary superheater, a primary desuperheater water spray regulating valve is controlled by the output, a set value of a main control loop of secondary desuperheating water spray is a main steam temperature, and an input signal of an auxiliary control loop is a post temperature of a secondary spray desuperheater; a cascade control system is adopted as a controller, an intelligent neural network controller is adopted as a main controller, a PID (proportion integration differentiation) controller is used as an auxiliary controller, and tracking modules are arranged at output ends of the main loop PID controller and the intelligent neural network controller. The method can allow operators to regulate operation timely to achieve the purposes of reliability and high efficiency, and has great transportability and dynamic expandability, and the problems of long time for conventional PID regulation and poor adaptive capability are effectively solved.

The invention discloses a self-adaptation dead-time compensation method for H-bridge cascade STATCOM (static synchronous compensator) and aims to solve the problem of lack of dead-time compensation directly targeting the H-bridge cascade STATCOM. According to a circuit topological structure of the H-bridge cascade STATCOM, the method includes steps of acquiring a discrete mathematic model of the H-bridge cascade STATCOM in a three-phase coordinate system; converting the discrete mathematic model into a transfer function mode in the discrete state; online monitoring difference between STATCOM output voltage and reference voltage caused by the dead-time effect by a discrete disturbance monitor in real time, utilizing the monitored difference as compensation capacity to introduce into a H-bridge cascade STATCOM control system, and self-adaptation dead-time compensation is realized.

The invention discloses a power plant denitration ammonia injection control system, wherein a cascade control system is adopted to improve the response speed of inlet NOX concentration disturbance andcomprises: a dynamic differential feedforward of reactor inlet NOX concentration, a denitration efficiency feedforward, a load change feedforward, PID modification parameters and a control process ofoutlet NOX deviation correction, and the denitration ammonia injection control system adopts a waveform judgment method for callback. The judgment logic of the waveform judgment method is as follows:when the outlet NOX concentration curve has a sinusoidal oscillation waveform, the ammonia injection amount is quickly called back in the second quarter period of the sinusoidal oscillation waveform.According to the cascade control system for calculating the NH3 demand quantity according to NOX at the inlet of the SCR reaction zone, the ammonia spraying response speed is increased; outlet NOx deviation correction is added in a control algorithm, so that static deviation is eliminated; and meanwhile, a waveform judgment method is adopted for callback, so that the phenomenon of output oscillation is prevented, and thereby, the problems of response lag of inlet NOx concentration disturbance and output oscillation are solved.

The invention provides a compensation method for unknown network delay of a network cascade control system, belonging to the technical field of network control systems. The method adopts a network data transmission process among all forward and feedback network path nodes of the actual network cascade control system to replace a network delay compensation model thereof, avoids measurement, observation, estimate or identification for unknown delay of network data transmission among the nodes, and also avoids the synchronization requirement on node clock signals. The method can reduce the influence of unknown network delay on stability of the system and improve the control performance quality of the system. The method is suitable for dynamically compensating and controlling unknown network delay in all forward and feedback network paths of network simultaneously existing in the network cascade control system, when mathematical models of main auxiliary controlled objects are known or unknown, the system has unknown interference, and the network exists a certain amount of data packet losses.

A problem to be solved by the present invention is to provide a minimum information entropy-based evaluation method of a parallel cascade control system. The method is used for evaluating performanceof the parallel cascade control system, and the method disclosed in the present invention is invented to solve problems of a conventional evaluation method of the parallel cascade control system. Themethod disclosed in the invention is aimed at evaluating the performance of the parallel cascade control system via use of minimum information entropy reference. A minimum information entropy index can not only correctly be used for reflecting the performance of the parallel cascade control system in Gaussian perturbation, but can also be used for well reflecting the performance of the parallel cascade control system in non-Gaussian disturbance. The minimum information entropy index can be used for effectively reflecting the performance of the parallel cascade control system based on comparison with evaluation results of minimum variance and the minimum variance with forgetting factors. Shortcomings of the conventional evaluation method of the parallel cascade control system can be overcome, and limitations of the evaluation method of the parallel cascade control system can be prevented.

The invention discloses an automatic control method of Rp value of the alumina digestion outlet in the Bayer process, relating to a control method in the digestion of alumina production in the Bayer process, characterized in that: using an intelligent optimal setting technique aiming at searching the optimum Rp value of the digestion outlet, and according to the Rp target value of the digestion outlet, laboratory Rp value of the digestion outlet, the alumina concentration in slurry in the digestion inlet, the solid content of the grinding outlet, supplementary mother liquor concentration and temperature, and ore component value, intelligently setting the density value of the slurry in the inlet of the digestion system by the computer. According to the invention, by using the soft sensing technique to continuously measure the density value of the slurry in the digestion inlet, using the intelligent optimal setting technique to automatically set the density value of the slurry in the digestion inlet, and using the cascade control system to realize the automatic control of the Rp value of digestion outlet, the stability of alumina indexes is guaranteed.

The invention discloses an electromyographic humanoid dexterous prosthetic hand cascade control method, which comprises the following steps: under mode control, acquiring mode electromyographic signals and multiplex electromyographic signals of a user; sampling the mode electromyographic signals, adding a moving window; calculating out characteristics of the mode electromyographic signals under the moving window; inputting the characteristics of the electromyographic signals into a classifying model, and generating an action mode command; switching to state control via a swticher, in accordance with enerngy of the multiplex electromyographic sensor signals and the action mode command, generating an action mode control state and driving a humanoid dexterous prosthetic hand to move; and after the prosthetic hand is stopped in moving, switching to mode control via the switcher. The invention also relatdes to an electromyographic humanoid dexterous prosthetic hand cascade control system; and by collecting residual limb muscle change signals via a mode electromyographic sensor and a multiplex electromyographic sensor, the electromyographic humanoid dexterous prosthetic hand can be controlled to do expected actions. According to the cascade control method and the cascade control system provided by the invention, control precision and reliability of the humanoid dexterous prosthetic hand can be enhanced, and a receptance rate and a popularizing rate of the prosthetic hand can be improved.

The invention discloses an aquaculture pond PH value control system with a wireless sensor network. The system is composed of an aquaculture pond environment parameter collection and control platform and an aquaculture pond PH value cascade control system based on a composite controller. The aquaculture pond PH value control system with the wireless sensor network is designed according to the characteristics of the large working condition area of aquaculture pond environment PH value parameters, the nonlinearity and large lag of PH value changes, the unbalanced distribution of the pond PH value and the like. The system has huge application and popularization value in improving the stability of control over the aquaculture pond PH value and increasing the economic benefit of aquaculture.