30results about How to "Realize double closed-loop control" patented technology

The invention discloses a method and a device for feedback control of the air quantity of a central air conditioner, which relates to a control technique for the central air conditioner. An existing air conditioner has an overlarge air quantity, wastes energy sources, blows hot and cold in turn and has a poor indoor comfort level. The method comprises the following steps of: 1) performing detection, namely detecting the air quantity at an outlet of a fan coil unit by a air quantity detection device, and measuring the indoor temperature by a temperature detection device; 2) performing air quantity calculation, namely, comparing the actual temperature with a set temperature to obtain the difference value of the actual temperature and the set temperature, and calculating the needed air quantity according to the temperature difference value; 3) performing air quantity compensation, namely, comparing the actual air quantity with the needed air quantity to obtain the difference value of the actual air quantity and the needed air quantity, calculating the rotating speed of a fan motor according to the air quantity difference value, and compensating the air quantity; and 4) performing regulation, namely performing the regulation according to the calculated rotating speed of the fan motor, and returning to the step 1) for circulation. The method and the device use a PI regulating unit to regulate the rotating speed of the motor so as to regulate the output air quantity, realize the double closed-loop control of the temperature and the air quantity, and achieve the effects of improving the comfort level and saving energy.

The invention relates to a controller of a converter of a dual-fed wind power generator, which is formed by connecting a touch display screen, a PLC module, a data acquisition and control module and a network interface module, wherein the touch display screen is connected with the PLC module, the PLC module is connected with one end of the network interface module, the other end of the network interface module is connected with a control and pitch control system of a wind turbine, the PLC module is further connected with the data acquisition and control module, and the data acquisition and control module is simultaneously connected with a rotor side power module and a network side power module. The controller adopts the modular design and can realize the double closed-loop control of a power outer loop and a current inner loop through acquisition, analysis and treatment of various analog signals, digital quantity signals and rotation speed signals, and simultaneously realize the functions of centralized acquisition of data, fault prediction, diagnosis and the like, and has the characteristics of strong anti-interference ability, abundant network interfaces, fast measurement speed, high control precision, friendly man-machine interface and the like.

The invention provides an engine rail press precontrol and feedback control device as well as a control system and a control method. In the device, an ECU (electronic control unit) is connected with a constant current control unit, the constant current control unit is respectively connected with a high-pressure oil pump fuel gauging unit, a PWM (pulse width modulation) drive unit and a signal processing unit, the signal processing unit is connected with the ECU, and the ECU is connected with the PWM drive unit. The control system comprises a rail press precontrol module and a rail press feedback control module, wherein the rail press precontrol module is used for calculating the current value corresponding to the targeted rail press under the specific engine working condition; and the rail press feedback control module is used for realizing the feedback control on the targeted rail press by adjusting the PWM driving pulse duty cycle. In the method, the current value corresponding to the targeted rail press under the specific engine working condition can be calculated and then divided into two parts, wherein one part of current can be sent to the constant current control unit by the ECU and the other part of current can be added to feedback current in order to realize the feedback control on the targeted rail press by adjusting the PWM driving pulse duty cycle. The invention has the characteristics of fast response time, good following performance and precise control.

The invention provides a negative-high-voltage direct-current integrated power supply for an X-ray tube and a control method thereof. The device comprises a negative high voltage generation module, a control module and a filament alternating voltage generation module. The negative high voltage generation module comprises a first PWM generation circuit, a first inverter circuit, a first resonance circuit, a high-frequency boosting transformer and a dual voltage rectifying circuit. The filament alternating voltage generation module comprises a second PWM generation circuit, a second inverter circuit, a second resonance circuit and a high-frequency step-down transformer. The control module comprises a sampling feedback circuit, a control circuit and an input and output control circuit. The method achieves double-loop control of negative-high-voltage direct-current voltage of the X-ray tube and tube currents of the X-ray tube, and a sliding mode variable structure is applied to a negative-high-voltage control loop with high frequency variable structure characteristics, so that a negative-high-voltage voltage stabilizing loop has good robustness. A water cooling device is generally not needed when the negative-high-voltage direct-current integrated power supply is adopted in the X-ray tube with low power, the size is small, and heat dissipation of the X-ray tube is facilitated.

The invention discloses a suspension control method of an electromagnetic constant conduct low-speed magnetic-levitation train. The method comprises the steps: respectively obtaining an existing suspension gap between an end A and an end B of each suspension module, existing speed and existing virtual flux; respectively taking the existing suspension gaps between the ends A and B of the suspension modules and the existing speed as outer ring feedback quantity, and calculating expected virtual fluxes between the ends A and B of the suspension modules by the combination of the set suspension gaps; respectively taking the existing suspension gaps between the ends A and ends B of the suspension modules as inner ring feedback quantity, and calculating controlled quantity signals of the ends A and B of the suspension modules by the combination of the expected virtual fluxes between the ends A and B of the suspension modules, so as to realize the stable suspension of the ends A and B of the suspension modules. According to the suspension control method provided by the invention, a nonlinear coupling relationship among suspension force, suspension current and suspension gaps can be prevented, the inherent defects based on the inner ring control method of current can be overcome, the tracking performance and robust performance of the suspension system can be improved, a hardware sensor is not needed, the implementation cost is low, and the reliability is high.

The invention discloses a stable tracking control method applied to a trough type solar condenser. A controller detects that a tracking control starting signal is effective, and enters a stable tracking processing module. The method comprises the steps that firstly, an angle difference value delta theta is calculated and judged; then, the obtained angle difference value is compared with a set value delta theta 0, and a tracking mode is determined; if the angle different value is larger than the set value, a control motor carries out tracking with constant rotating speed; if the angle difference value is smaller than or equal to the set value, a control method of two-point calibration is adopted, and the instantaneous value v of the speed is obtained through a computational formula according to a time instantaneous value t to control the rotating speed of the control motor for tracking. The rotating speed of the control motor is changed in real time, therefore, the defects that according to a traditional control method, speed steps exist in the tracking process, consequently, the tracking angle is hard to control, and tracking precision is insufficient are overcome, and the stability of tracking control is improved.

The invention discloses a multichannel control device used for a hydraulic vibration test system. The multichannel control device comprises an upper computer and a lower computer which is electrically connected with the upper computer. The lower computer comprises a power board card, a processor board card and a signal conditioning board card. The power board card provides a DC power supply. The processor board card is used for completing signal acquisition, processing and control computation. The signal conditioning board card is used for signal conditioning. The power board card comprises a power supply output interface. The power board car is connected with the processor board card through the power supply output interface. The processor board card comprises a network port circuit, multiple hybrid interfaces and a digital interface. The processor board card receives instructions and parameters issued by the upper computer through the network port circuit and uploads the data to the upper computer and is electrically connected with the a signal conditioning board card through the hybrid interfaces. The device is simple and feasible in operation, stable and reliable and high in universality and can be widely applied to various hydraulic vibration test systems.

The invention relates to a control system for a laser, and particularly discloses a light power optimization control system for a metallic-seal radio-frequency carbon dioxide laser. The light power optimization control system comprises a control computer and a laser, wherein the laser comprises a control board and a laser tube core connected with the control board, the control computer transmits a preset output power value to the control board via a digital communication interface, and the control board controls the output power of the laser tube core according to the preset output power value; and an embedded laser detection module is also connected on the control board, and the laser detection module tests the actual output power value of the laser tube core and feeds the actual output power value back to the control board so as to dynamically adjust the actual output power of the laser tube core. In the invention, the defects of the PWM (Pulse Width Modulation) control way are overcome, and the accurate control of output power is realized.

The invention provides a bridge crane positioning and anti-swing control method for achieving random parking. The positioning and anti-swing control that ensures random parking of a trolley is achieved as follows: the operation speed of the trolley is taken as an expected speed, the initial load swing angle is zero, and a pre-constructed crane random parking position positioning anti-swing controller taking the speed as an input is adopted; before a stop signal is given, only the load swing angle feedback anti-swing control is carried out; after the stop signal is given, the displacement of the trolley is set to be zero when the stop signal is given, the displacement of the trolley is calculated using the trolley speed fed back by a speed encoder in real time, and the position closed-loopcontrol is carried out, so that the double-closed-loop control is achieved. The positioning and anti-swing control for a cart is the same as that for the trolley. Random parking can be achieved, the use of a position sensor is reduced, the simple speed encoder is used for carrying out short-distance position feedback, the cost is reduced while the control effect is not influenced, and the controlsystem is simpler and can resist external impact.

The invention relates to a straight line movement type accelerator executor. The straight line movement type accelerator executor comprises a base board, a shell body, a direct current motor and a transmission mechanism; an output end of the motor is connected with an input end of the transmission mechanism; the transmission mechanism is composed of a decelerating mechanism and a spiral transmission mechanism, the decelerating mechanism is formed by the match between a worm fixedly connected with the direct current motor and a worm gear component fixedly connected with a transmission screw, the spiral transmission mechanism is formed by the transmission screw and an accelerator push-pull rod which are combined in a spinning mode, a feedback potentiometer is installed on one side of the transmission screw, and a control circuit is installed on the base board. According to the accelerator executor, a control circuit board is integrated, the accelerator executor can be controlled by a CAN communication receiving and dispatching module, and the use cost is lowered. By the adoption of the double closed loop control, the control precision is improved. By the adoption of the worm gear and worm transmission, decelerating is conducted, the size of the structure is smaller, the assembly and maintenance are easier, the shape size of the accelerator executor is smaller, the weight is lighter, and the installation is more convenient.

The invention provides a negative-high-voltage direct-current integrated power supply for an X-ray tube and a control method thereof. The device comprises a negative high voltage generation module, a control module and a filament alternating voltage generation module. The negative high voltage generation module comprises a first PWM generation circuit, a first inverter circuit, a first resonance circuit, a high-frequency boosting transformer and a dual voltage rectifying circuit. The filament alternating voltage generation module comprises a second PWM generation circuit, a second inverter circuit, a second resonance circuit and a high-frequency step-down transformer. The control module comprises a sampling feedback circuit, a control circuit and an input and output control circuit. The method achieves double-loop control of negative-high-voltage direct-current voltage of the X-ray tube and tube currents of the X-ray tube, and a sliding mode variable structure is applied to a negative-high-voltage control loop with high frequency variable structure characteristics, so that a negative-high-voltage voltage stabilizing loop has good robustness. A water cooling device is generally not needed when the negative-high-voltage direct-current integrated power supply is adopted in the X-ray tube with low power, the size is small, and heat dissipation of the X-ray tube is facilitated.

The invention provides a self-adaptive control method for stability and roundness of an ultra-large ring piece in the radial and axial rolling process. The self-adaptive control method comprises the steps of rolling ring stability control based on conical roller rotating speed fuzzy adjustment and rolling ring roundness control based on guiding force feedback. According to the method, in rolling ring stability control based on conical roller rotating speed fuzzy adjustment, arithmetic average filtering method processing is carried out on input ring center offset and offset change rate, and amplitude limiting processing is carried out on conical roller rotating speed adjusting quantity. According to the self-adaptive control method for the stability and roundness of the ultra-large ring piece in the radial and axial rolling process, the rolling stability control method based on conical roller rotating speed amplitude limiting filter fuzzy adjustment is provided by aiming at out-of-round and unstable deformation states in the rolling process of the ultra-large ring piece on the basis of conventional motion planning control of radial and axial ring rolling equipment, a rolling roundness control strategy based on guiding force feedback is formulated, the rolling roundness and stability of the ring piece are controlled by adjusting roller movement in real time, and the stability and roundness of the ultra-large ring piece in the rolling process can be considered.

The invention discloses a friction plug rivet welding system based on a programmable logic controller (PLC), and relates to the field of welding equipment. The welding system comprises four modules including a plug rivet welding mechanical device, a servo drive system, a main control system and a man-machine interaction interface. The plug rivet welding mechanical device has two degrees of freedomof rotation and axial direction, and the axial degree of freedom provides downward pressure during welding. The main control system continuously collects displacement and pressure values during welding so as to ensure that the welding process is controlled in real time. The friction plug rivet welding system utilizes high-speed rotation and certain pressure of a special rivet to penetrate throughan upper plate, stops pressing downwards after the rivet penetrates through the upper plate, continuously rotates to generate heat and melts a base plate, and then completes welding of the rivet andthe base plate under the action of pressure. The welding system not only achieves connection of ultra-high strength steel and an aluminum alloy, but also performs double closed-loop control on the axial displacement during welding, and ensures the welding precision.

The invention discloses a hardware current sharing device and a working method thereof, the device comprises a plurality of current sharing ICs, the plurality of current sharing ICs is connected through a current sharing bus, and any current sharing IC comprises a current comparison module, a current tracking module and a gain feedback module. The method comprises the steps of obtaining an output current of a current PSU; obtaining output currents of other PSUs in the multi-node server; comparing the plurality of output currents, with the plurality of output currents including the output current of the current PSU and the output currents of other PSUs, defining the PSU with the maximum current as a master module, and defining the other PSUs as slave modules; controlling the slave modules to adjust the output current according to the difference between the output current of the master module and the output currents of the slave modules; acquiring feedback current in a transconductance mode according to the comparison result of the multiple output currents and the output currents adjusted by the slave modules; and outputting the feedback current to LLC half-bridge resonance in the PSUs. According to the invention, the PSU current sharing sensitivity and current sharing precision can be effectively improved, and the stability of a server system is improved.

The invention belongs to the field of air conditioner power supply circuits, particularly relates to an air conditioner emergency ventilation power supply circuit system, and solves the problems thatan air conditioner emergency ventilation power supply has no real-time display fault window, is low in adjustability, does not have fault self-diagnosis and self-repair capabilities, is poor in faultstorage and analysis and is low in fan load damping adaptability, and that the output voltage is greatly influenced by the input voltage, the output wind power is unstable and the like. The air conditioner emergency ventilation power supply circuit system comprises a control module, an input module, an output module and a boosting module, the control module comprises a DSP micro control panel andan I / O driving board, and pins are arranged on the I / O driving board and are connected with sensors. A power supply of the invention is convenient for observing the operation condition of the air conditioner emergency ventilation power supply and adjusting the output voltage and frequency, convenient for diagnosing, analyzing, processing and storing faults, and convenient for adapting to change offan load damping and input voltage. The power supply circuit system is suitable for emergency power supply of the train air conditioner emergency ventilation power supply.

The invention relates to a PMSM (permanent magnet synchronous motor) speed and position estimation method based on a parameter self-adaptive EKF (extended Kalman filter), which realizes double-closed-loop control of a current loop and a speed loop of a motor according to an SVPWM (space vector pulse width modulation) theory and a method for controlling a motor vector. Ualpha, ubeta and ialpha and ibeta under an alpha-beta static coordinate system are obtained through FOC control and serve as input of an extended Kalman filtering algorithm, meanwhile, phase resistance, phase inductance and flux linkage of the motor need to serve as input parameters, and the rotor rotating speed we and the rotor position theta are obtained through extended Kalman recursion. Compared with traditional extended Kalman filtering, an accurate process noise variance Q must exist when a priori estimation covariance is obtained, the improved method provided by the invention is used for obtaining the priori estimation covariance based on a posteriori estimation information sequence as feedback, and the problem of dependence on the process noise covariance Q is solved.

The invention relates to a controller of a converter of a dual-fed wind power generator, which is formed by connecting a touch display screen, a PLC module, a data acquisition and control module and a network interface module, wherein the touch display screen is connected with the PLC module, the PLC module is connected with one end of the network interface module, the other end of the network interface module is connected with a control and pitch control system of a wind turbine, the PLC module is further connected with the data acquisition and control module, and the data acquisition and control module is simultaneously connected with a rotor side power module and a network side power module. The controller adopts the modular design and can realize the double closed-loop control of a power outer loop and a current inner loop through acquisition, analysis and treatment of various analog signals, digital quantity signals and rotation speed signals, and simultaneously realize the functions of centralized acquisition of data, fault prediction, diagnosis and the like, and has the characteristics of strong anti-interference ability, abundant network interfaces, fast measurement speed,high control precision, friendly man-machine interface and the like.

An electrical control system of a numerical control machine tool comprises a control unit, a control instruction generation unit, a display unit, a main shaft frequency conversion system, a servo driving system, a tool changing system and a hydraulic system. The input end of the control unit is connected with the control instruction generation unit, and the output end of the control unit is connected with the display unit, the main shaft frequency conversion system, the servo driving system, the tool changing system and the hydraulic system. A simulation control signal is generated by the control unit according to a simulation instruction, and machine tool machining simulation is performed. The simulation result is sent to the display unit, the simulation result is displayed through the display unit, if the simulation result conforms to a machining drawing, workpiece machining can be started, and if the simulation result does not conform to the machining drawing, the simulation instruction can be returned to be input again, the input simulation instruction is changed and simulated again, and therefore, the use procedure of a user is simplified, the market requirement is met, and wide application prospects are achieved.

The invention relates to a power compensation type rare earth permanent magnet motor and a control method. The power compensation type rare earth permanent magnet motor comprises a shell and a power compensation assembly arranged at the top of the shell. A plurality of stators are arranged on the inner wall of the shell, the stators are distributed around the inner wall of the shell at intervals, and excitation coils are arranged on the outer sides of the stators; a rotor is connected in the shell in a matched mode in the center line direction, magnetic steel is arranged at one end of the rotor, and a plurality of permanent magnets are arranged on the outer side of the magnetic steel at intervals in the circumferential direction. The power compensation assembly comprises a first compensator and a second compensator, the first compensator and the second compensator are both connected with a current detection mechanism, the first compensator is matched with the second compensator, and a switching mechanism is arranged between the first compensator and the second compensator; the switching mechanism can gate the first compensator or / and the second compensator to operate; and a correction unit is arranged in the power compensation assembly, and the correction unit is provided with a power input end and a power output end.

The invention discloses a method and a device for feedback control of the air quantity of a central air conditioner, which relates to a control technique for the central air conditioner. An existing air conditioner has an overlarge air quantity, wastes energy sources, blows hot and cold in turn and has a poor indoor comfort level. The method comprises the following steps of: 1) performing detection, namely detecting the air quantity at an outlet of a fan coil unit by a air quantity detection device, and measuring the indoor temperature by a temperature detection device; 2) performing air quantity calculation, namely, comparing the actual temperature with a set temperature to obtain the difference value of the actual temperature and the set temperature, and calculating the needed air quantity according to the temperature difference value; 3) performing air quantity compensation, namely, comparing the actual air quantity with the needed air quantity to obtain the difference value of theactual air quantity and the needed air quantity, calculating the rotating speed of a fan motor according to the air quantity difference value, and compensating the air quantity; and 4) performing regulation, namely performing the regulation according to the calculated rotating speed of the fan motor, and returning to the step 1) for circulation. The method and the device use a PI regulating unit to regulate the rotating speed of the motor so as to regulate the output air quantity, realize the double closed-loop control of the temperature and the air quantity, and achieve the effects of improving the comfort level and saving energy.

The invention discloses a control circuit of a wide-voltage brushless motor. The control circuit is self-adapted to the working voltage of a power tube and can sense the voltage and the current of a power switch tube. The control circuit comprises a microprocessor, a motor-driving circuit, a power output circuit and a DC-DC (direct current) converting circuit, wherein the power output circuit comprises three power-driving groups, the DC-DC converting circuit is used for converting a stabilized-voltage power supply which is used for supplying DC voltage to the microprocessor and the power output circuit into the stabilized-voltage power supply which is respectively used for supplying DC working voltage to the microprocessor and the power output circuit, each power-driving group comprises an upper power switch tube and a lower power switch tube, the source electrodes or the emitting electrodes of all the lower power switch tubes are connected with the corresponding A / D (Analog to Digital)input ends of the microprocessor by a sampling amplifying circuit after the source electrodes or the emitting electrodes of all the lower power switch tubes are connected in parallel, the three output ends of the power output circuit, i.e. the connecting parts of the source electrodes or the emitting electrodes of the upper power switch tubes and the drain electrodes or the collecting electrode of the lower power switch tubes, are respectively connected through the corresponding A / D (Analog to Digital)input ends of the microprocessor by one sampling amplifying circuit. The control circuit is mainly used for driving the brushless motor.

The invention discloses a water and fertilizer integrated precise control method and system based on double closed loops, the system comprises a fertilizer injection ring, an irrigation ring and a mixing actuator, the fertilizer injection ring comprises a fertilizer injection amount controller and a water and fertilizer solution detector connected with the fertilizer injection amount controller, and the water and fertilizer solution detector is used for obtaining feedback of the fertilizer injection amount from a water and fertilizer solution; the fertilizer injection amount controller is used for controlling the multi-channel fertilizer applicator to output stable fertilizer injection amount; the irrigation ring comprises an irrigation amount controller and a water flow sensor, the irrigation amount controller is connected with the water flow sensor, the water flow sensor is used for obtaining feedback of the water injection amount from the water and fertilizer solution, and the irrigation amount controller is used for controlling the booster pump to output stable irrigation amount and eliminate irrigation amount deviation; the mixing actuator is connected with the fertilizer injection ring and the irrigation ring, and a water-fertilizer stock solution of the fertilizer injection ring and filtered water of the irrigation ring are mixed in the mixing actuator to form a water-fertilizer solution with fixed concentration. The water-fertilizer ratio can be accurately and rapidly controlled, and the water-fertilizer ratio adjusting time is saved.

The invention discloses a stable tracking control method applied to a trough type solar condenser. A controller detects that a tracking control starting signal is effective, and enters a stable tracking processing module. The method comprises the steps that firstly, an angle difference value delta theta is calculated and judged; then, the obtained angle difference value is compared with a set value delta theta 0, and a tracking mode is determined; if the angle different value is larger than the set value, a control motor carries out tracking with constant rotating speed; if the angle difference value is smaller than or equal to the set value, a control method of two-point calibration is adopted, and the instantaneous value v of the speed is obtained through a computational formula according to a time instantaneous value t to control the rotating speed of the control motor for tracking. The rotating speed of the control motor is changed in real time, therefore, the defects that according to a traditional control method, speed steps exist in the tracking process, consequently, the tracking angle is hard to control, and tracking precision is insufficient are overcome, and the stability of tracking control is improved.

The invention relates to a current control device for a three-freedom-degree motion permanent magnet spherical stepping motor, and the device comprises a main control station, a control module, a drive module, and a position detection module. The main control station is formed by a PC, and is connected with the control module. The control module comprises a microprocessor, and is connected with the drive module through a data bus. The drive module comprises an inversion circuit, a drive circuit, an overcurrent protection circuit, and a current sampling circuit. The output end of the drive module is connected with 24 stator coils of the permanent magnet spherical stepping motor, and the position detection module is connected with the control module through a position signal communication bus. The device can output a big-power and high-precision drive current, is simple in structure, is high in response speed, and is high in control efficiency.

The invention relates to a double-time-scale voltage control method based on a dynamic-static reactive power replacement mechanism; the method comprises the steps: building a long-time-scale voltage control model, using the minimum hub node voltage deviation of tracking control at all time points as a target function, and using a power grid operation power flow constraint, a capacitor bank adjusting performance constraint and a node operation voltage constraint as constraint conditions; building a short time scale rolling optimization model, taking the minimum voltage prediction control deviation at n time points in a prediction window as an objective function, and taking consideration of static var generator output lower limit and upper limit constraints, climbing constraints and power grid operation voltage constraints as constraint conditions; solving a short-time scale rolling optimization model by adopting a rolling optimization control method based on model predictive control; building a dynamic-static reactive power replacement model; and determining a capacitor compensation node switching sequence in the dynamic-static reactive power replacement process and a precedence sequence of power vacancy undertaken by the compensation nodes of the static var generator. The method can adapt to various voltage fluctuation scenes, and has high voltage control precision.