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

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 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 relates to a current control device for a three-degree-of-freedom motion permanent magnet spherical stepping motor, including a main control station, a control module, a drive module, and a position detection module. The main control station is composed of a PC and connected to the control module. The control module includes a microprocessor and is connected to the drive module through a data bus. The drive module includes an inverter circuit, a drive circuit, an overcurrent protection circuit and a current sampling circuit. The output ends of the drive module are respectively connected to the permanent magnet spherical stepping motor. The 24 stator coils are connected, and the position detection module is connected with the control module through the position signal communication bus. The invention can output high-power, high-precision driving current, and has the advantages of simple structure, fast response, high control efficiency and the like.

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 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 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 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 an adaptive control method for the stability and roundness of the radial and axial rolling process of super-large rings, including: rolling ring stability control based on the fuzzy adjustment of the cone roll speed and rolling ring roundness based on guide force feedback control; this method is also based on the rolling ring stability control based on the fuzzy adjustment of the cone roll speed, the input ring center offset and the offset change rate are processed by the arithmetic mean filter method, and the cone roll speed adjustment is limited. . The self-adaptive control method for the stability and roundness of the radial and axial rolling process of super-large rings according to the present invention aims at the out-of-circle and unstable deformation states in the rolling process of super-large rings, and uses the conventional motion planning of radial and axial ring rolling equipment Based on control, a rolling stability control method based on conical roll speed limiting filter fuzzy adjustment is proposed, a rolling roundness control strategy based on guiding force feedback is formulated, and the rolling roundness and stability of ring rolling are controlled by real-time adjustment of roll motion. It can take into account the stability and roundness of the super-large ring rolling process.

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.