656results about How to "Simple control structure" patented technology

An optical unit with shake correcting function may include a movable module on which at least an optical element is mounted, a fixed body which supports the movable module, a shake detection sensor which detects a shake of the movable module, a drive mechanism for shake correction for swinging the movable module on the fixed body on the basis of a detection result of the shake detection sensor to correct the shake of the movable module, and a control section which controls the drive mechanism for shake correction on the basis of the detection result of the shake detection sensor. The shake detection sensor is a gyroscope mounted on the movable module and the control section controls the drive mechanism for shake correction so as to cancel the shake detected by the gyroscope.

The invention discloses a parallel structure and a control method for a photovoltaic power generation grid-connected inverter and belongs to the technical field of renewable energy sources. A topological circuit structure of the photovoltaic power generation grid-connected inverter is divided into a parallel structure of single-phase voltage type pulse-width modulation (PWM) inverters and a parallel structure of three-phase voltage type PWM inverters; and in the control method, an outer ring regulator of a control circuit of the parallel voltage type PWM inverters is independent based on a power grid voltage-oriented vector control technology in a control mode of voltage outer ring and current inner ring so as to form a common unified outer ring regulator; control strategies of various inverters are simplified into single closed loop current control so as to achieve the consistency of energy flow directions of the parallel voltage type PWM inverters and avoid ring current; and the parallel current sharing of the voltage type PWM inverters is realized. Therefore, multiple modules of the voltage type PWM inverters are connected in parallel to realize high-power modularized large-scale application.

The invention belongs to the field of power converter control and relates to a model prediction control method of a voltage source type rectifier when a network voltage is unbalanced. The model prediction control method of the voltage source type rectifier when the network voltage is unbalanced comprises the steps of converting three-phase network voltage and a three-phase current into network voltage and a current which are under a two-phase static coordinate system through an abc / alpha beta coordinate, obtaining network positive sequence voltage and negative sequence voltage by carrying positive and negative sequence component separation of the network voltage under the two-phase static coordinate system, calculating reference values of active power, calculating current reference values of the rectifier under the two-phase static coordinate system, and carrying out model prediction current control and selecting an optimal on-off state. The model prediction control method of the voltage source type rectifier when the network voltage is unbalanced is capable of quickly and precisely tracing the current under the two-phase static coordinate and effectively eliminating fluctuation of direct current side voltage at the same time, power quality of the system is improved, a reliable network-connected operation of the rectifier when transient state network voltage is unbalance is achieved, and dynamics and stability of the whole system are improved.

The invention relates to a controller of full-power alternative-direct converter used in wind generation, wherein the alternative-direct converter is formed by network converter and the convert of generator; the used generator is a permanent-magnetic generator; the rotor is in permanent-magnetic structure, without external magnetic activate power supply; two convert loops both uses the PWM converters operating in four quadrants, based on full-control element, which can improve the dynamic response, reduce cost and impact, realize bidirectional transmission of electricity, and realize generating via power factor sine wave current parallel network; and the invention uses improved direct torque technique to control the converter, to confirm the sine wave change of input current at the stator, with quick response, low vibration, torque dynamic control and wide speed adjust range.

The invention provides a new method for controlling flying shears for bars and wires based on T400, which is an advanced electrical control method for start-stop type flying shears for bars and wires. The method comprises the steps of accurate shearing-blade position control, shearing length control and automatic shearing optimization, and the like; in the process of production, when an upstream rolling mill has an accident, or the quality of a section of a rolled piece is poor, a fragmentation function can be started on line so as to carry out partial fragmentation or complete fragmentation on the rolled piece, and the fragmentation and shearing speed is in step with the running speed of the rolled piece automatically; and when the fragmentation operation is stopped, a flying shear is automatically positioned to a start position and enters into a standby state of the normal shear mode. In the invention, the powerful computation function of the T400 is fully used, core control parts of the flying shear are completely integrated into the T400, and high-speed counters, shaft positioning modules and touch screens are not required, therefore, the cost is reduced, and high accuracy is obtained; and when the flying shear carries out double-length shearing at a speed of 21 m / s, the double-length error is basically within 75 mm, and partial double-length error can be within 30 mm.

The invention relates to an active-disturbance-rejection trajectory linearization control method suitable for hypersonic velocity maneuvering flight. The active-disturbance-rejection trajectory linearization control method regards a part different from a nominal model as a general disturbance, establishes a hypersonic aircraft attitude and angular velocity dynamic model with multi-source complex uncertainty and strict feedback form, designs attitude ring and angular velocity ring model auxiliary expansion state observers, adopts a non-linear tracking differentiator to arrange a transition process for a given guidance command and generate a nominal command of an attitude ring, designs an active-disturbance-rejection trajectory linearization attitude ring controller containing a feedforward tracking control law, a feedback stabilization control and a disturbance compensation term, and designs an active-disturbance-rejection trajectory linearization angular velocity ring controller containing a feedforward tracking control law, a feedback stabilization control and a disturbance compensation term. The active-disturbance-rejection trajectory linearization control method achieves high-precision anti-disturbance control under the given conditions of large-margin guidance command and control constraint, and has high adaptability for multi-source disturbance large-scale perturbation in hypersonic velocity long-span maneuvering flight.

The invention discloses a control method of a three-phase grid-connected inverter based on a modified proportional resonant regulator. The method comprises the following steps of: firstly, computing according to given active and reactive powers of the inverter and a voltage of a power grid to obtain required d-axis and q-axis currents under a synchronous coordinate system, and performing coordinate transformation by combining with phase information which is measured by a phase locking loop and a measured three-phase voltage signal of the power grid to obtain a current reference signal under a stationary alpha-beta coordinate system; secondly, performing coordinate transformation on an output current signal of the inverter to the alpha-beta coordinate system, controlling and tracking the current reference signal by the modified proportional resonant regulator with a harmonic compensator; and finally, returning to an abc coordinate system by coordinate transformation to generate a pulse-width modulation (PWM) pulse-control three-phase full-bridge inverter output, so as to make a distributed generation system grid-connected for power generation. By the method, a large number of complicated computation processes are eliminated, and a control structure is simplified. The control method of the three-phase grid-connected inverter based on the modified proportional resonant regulator is an accurate and high-efficiency novel inverter control method and has a bright development future.

Provided is a multi-purpose imaging apparatus (10) comprising a body (14) and imaging means (36) housed within the body (14). The body (14) is adapted to releasably engage an adaptor (12). The adaptor (12) has an aperture (108) extending therethrough that aligns with the optical axis (X) of the imaging means (36) when so engaged, such that at least a portion of the optical axis (X) is not obscured. The adaptor (12) also has optics for illuminating a subject within the optical axis (X) for diagnostic purposes.

The invention discloses a frequency conversion driving control system and method based on an electrolysis-free capacitive inverter. The method comprises the following steps: detecting system input voltage current, bus voltage, motor phase current and rotating speed; carrying out Clark and Park conversion on three-phase current to obtain d and q axis current; carrying out error adjustment on a given rotating speed and an actual rotating speed; calculating q axis given current according to input voltage current, speed ring output and capacitance; calculating d axis given current according to voltage; calculating d and q axis error current and carrying out PI adjustment to obtain d and q axis actual voltage; limiting amplitude of actual voltage to obtain d and q axis calculated voltage; carrying out error adjustment on the actual voltage and the calculated voltage and taking the result as current ring feedback; carrying out Park inverse conversion on the d and q axis calculated voltage to obtain alpha and beta axis voltage; and modulating the inverter to control a motor. By the frequency conversion driving control system and method based on the electrolysis-free capacitive inverter, the motor can run at high speed in a flux weakening region, a network side high power factor is obtained, a control structure is simplified, and the reliability of the system is improved.

The invention relates to a dynamic gas elastic foil bearing with stability and adaptive control functions, comprising a bearing casing, a plurality of bearing pads, an elastic foil, and a piezoelectric ceramics micro displacement actuator. The dynamic gas elastic foil bearing is characterized in that the bearing pads are uniformly distributed along the inner wall of the bearing casing; the bearing pads are welded with a bottom bump foil and one end of a top foil; the other end of the top foil is lapped over an adjacent top foil, wherein the piezoelectric ceramics micro displacement actuator with one end fixed on a set screw and the other end arranged on a jig is connected with two bearing pads; the piezoelectric ceramics micro displacement actuator is connected with a feedback controller PID; an input of the feedback controller PID is connected with an eddy current displacement sensor. The dynamic gas elastic foil bearing with stability and adaptive control functions has the advantages of strengthened equivalent rigidity and equivalent damping of the elastic foil, restrained vibration of rotor system, improved bearing capacity and stability of the bearing, reduced size and structure, increased control precision of displacement, and quickened response speed.

The invention provides a high-speed aircraft having tilting propellers and being capable of taking off and landing vertically and a flight control method of such high-speed aircraft. The high-speed aircraft is characterized in that canard wings are mounted at the head of a fuselage of the high-speed aircraft, wings and a vertical fin are mounted in the front of and above the tail of the fuselage respectively, the tilting propellers are mounted at the outer ends of two tilting arms, the two tilting arms are symmetrically mounted on two sides of the front middle of the fuselage, each tilting arm, along with the corresponding tilting propeller, can be tilted synchronously around a tilting arm axis, and a tail rotor driven by an independent motor is mounted at the tail of the fuselage and can deflect leftwards and rightwards around a vertical fuselage axis. The high-speed aircraft having tilting propellers and being capable of taking off and landing vertically has the advantages that the tilting propellers are mounted at the middle of the fuselage between the canard wings and forward-swept main wings, and in the vertical takeoff and landing stage, downwash airflow of the propellers does not flow through any fixed airfoils with no blockage, so that hovering efficiency of the whole aircraft can be increased; smooth transition of the aircraft from the vertical takeoff and landing to high-speed flying can be realized and control of flight conversion is easier due to small aerodynamic interference between the downwash airflow of the propellers and the fixed airfoils in a tilting process.

A water heater includes one or a plurality of heat pumps that heat tap water or return water from a hot water supply part, a circulation line that supplies hot water heated in the heat pumps to the hot water supply part, and introduces the return water from the hot water supply part to the heat pumps, an incoming water pipe that joins to between the hot water supply part in the circulation line and the heat pumps and supplies the tap water, a circulation pump that returns the return water to the heat pumps and circulates the return water through the circulation line, and a control unit that controls operation or stop of the circulation pump according to driving operation time or elapsed stop time by linking a combustion process of the heat pumps.

A pulse tube refrigerator includes a regenerator including a cold end and a hot end, a cold head connected to the cold end of the regenerator, a pulse tube having a cold end and a hot end and connected at its cold end to the cold head, a pressure fluctuation source connected to the hot end of the regenerator, a buffer connected to the hot end of the pulse tube through an orifice, and an auxiliary buffer connected to the hot end of the pulse tube through a buffer side control valve. The buffer and the auxiliary buffer may be replaced by a single buffer connected to the hot end of the pulse tube through an orifice and a buffer side control valve which are arranged in parallel.

The invention relates to the field of nonlinear compensation of band-gap reference, which is characterized in that: two branch circuit currents are added according to a principle of nonlinear subsection compensation; the currents are extracted and introduced into divider resistances of a reference output branch circuit according to an internal temperature negative feedback structure of the output branch circuit; and the temperature characteristics of an output reference voltage source are changed according to the influence of temperature coefficients of current extraction and introducing on output voltages in different temperature ranges to ensure that the output reference voltages repeatedly reach local extreme points in the whole working temperature range. The output voltage reference first derivatives with respect to the temperatures at the points are zero, so that the aim of subsection compensation is fulfilled, and the temperature coefficients of the output reference voltage source are effectively reduced.

The invention discloses a tri-axial platform servo motor control method based on the combination of a BP neural network and an active disturbance rejection controller. The tri-axial platform servo motor control method includes the following steps that 1, the kinetic equation of a tri-axial platform arbitrary-frame servo system containing a friction model is built; 2,according to the kinetic equation in the formula (I),the active disturbance rejection controller is designed; 3,a BP neural network parameter on-line setting module is designed and combined with the active disturbance rejection controller, and active disturbance rejection controller on-line parameter setting is achieved. By the adoption of the tri-axial platform servo motor control method based on the combination of the BP neural network and the active disturbance rejection controller, a flat top phenomenon and a dead zone phenomenon of a servo system can be basically eliminated, wherein the flat top phenomenon occurs during position signal tracking, and the dead zone phenomenon occurs during speed signal tracking; therefore, the position tracking precision and the speed tracking precision of the servo system can be improved.

The invention provides a method and assembling device for assembling and disassembling a stator and a rotor of a permanent magnet synchronous motor. The method is characterized by adopting a rocker arm vertical permanent magnet synchronous motor stator and rotor assembling and disassembling method to fix a rotor on a rocker arm by a floating positioning seat, with the excircle and end face at the shaft extension end or the excircle and end face at the extension end of the rotor as the positioning surfaces, plugging a tapered positioning pin after the floating positioning seat is fixedly positioned, ensuring the axis of the rotor to be vertical to the horizontal plane and on the same straight line with the center line of a stator and arranging a pilot rod at the front end of the rotor; fixing the stator on a stator positioning disc by a bolt, with a bearing chamber at the end where the end cover is assembled and the end face of the bearing chamber as the positioning surfaces; installing the stator positioning disc on which the stator is installed in the center of a stator fixing station and ensuring the central axis of the stator to be vertical to the horizontal plane and coaxial with the floating positioning seat of the rotor; installing the rocker arm on a column, driving the rocker arm to move up and down via a screw drive mechanism and driving the rotor installed on the rocker arm to move up and down together when the rocker arm moves up and down to realize assembly and disassembly of the stator and the rotor of the permanent magnet synchronous motor.

A driving circuit for Liquid Crystal Display (LCD) device includes a unity-gain operation amplifier (OP amp), three switches, and two capacitors. The unity-gain OP amp buffers and carries a signal voltage on a transmission line. The first switch switches a connection between a noninverting terminal of the unity-gain OP amp and an input line of the signal voltage. One end of the second switch is connected to the input line of the signal voltage. One end of the third switch is connected to the noninverting terminal of the unity-gain OP amp. The first capacitor is connected between the other end of the third switch and the other end of the second switch. The second capacitor is connected between the other end of the first capacitor and the ground voltage terminal.

The invention relates to a wind power tracking adaptive adjustment-based virtual inertia control method for double-wind-feeding generation set. The research on a virtual inertia control strategy of the wind generation set has an important role in improving the dynamic stability of the frequency of a wind power grid-connected system. The method comprises the following steps: firstly, analyzing an implementing theory of maximum wind power tracking based on a rotating speed controller of the double-fed wind generation set; then deducting a virtual inertia expression of the double-fed wind generation set based on a rotor motion equation by constructing connection between the frequency of a power grid and the kinetic energy of a rotor of the double-fed wind generation set, wherein at the same time, a maximum wind power tracking curve linear proportion adjustment-based rotating speed adjustment method for the double-wind-feeding generation set according to a secondary fitting function of a maximum wind power tracking curve; and finally, providing a wind power tracking adaptive adjustment-based virtual inertia control strategy for the double-wind-feeding generation set on the basis of the research, and verifying the validness of the control method by constructing a simulation model of the wind power grid-connected system.

The invention discloses a method for carrying out model prediction control on a grid-side converter of a photovoltaic power generation system under unbalanced voltage. According to the technical scheme, the method is characterized by including the first step of carrying out analytic calculation to obtain reference current of the AC side of the converter according to voltage of a sampling grid, delayed signals and given initial power, the second step of obtaining prediction current through a prediction model under the action of voltage vectors, the third step of selecting the voltage vector, which minimizes the absolute value of the difference between the current reference value and the current prediction value, as the optimal voltage vector through a value function, and the fourth step of selecting a switch position signal corresponding to the optimal voltage vector as a switching signal for controlling a power device. Under the condition of network voltage unbalance, it is guaranteed that DC bus voltage is stable and grid-side current is sinusoidal through the control of balance of the power of the two sides of the converter. The whole process is based on a two-phase static coordinate frame, and rotational coordinate conversion is avoided. Moreover, the control method does not include the positive and negative sequence decomposition and phase locking steps, the control structure is simple, and the calculated amount is small.

A rotary-type magnetic developing and change break includes mechanical section and magnetic control section. The mechanical section comprises rotor, stator and magnetic develop and change liquid in between. The magnetic control section comprises the inner layer of the rotor shaft wrapped with coil and out layer of plastic material.

The invention provides an adaptive augmented interference-resisting fault tolerance method for aiming at active segment flight of a vertical take-off and landing carrier, wherein the method belongs tothe field of aerial vehicle control technology. The method comprises the steps of 1, designing a basic PID controller; 2, designing an adaptive gain regulating law; 3, executing an interference compensating algorithm; 4, executing an optimal control distributing algorithm; and 5, executing a quick fault detecting and adaptive fault tolerance control algorithm. The method can satisfy an actual flight control requirement and realizes simple control parameter designing and detailed control performance indexes for representing. Furthermore the method has advantages of higher robustness, higher adaptability, simpler control structure, etc.

The method discloses a bearingless synchronous reluctance motor torque and suspension force direct controller and a construction method thereof. The bearingless synchronous reluctance motor torque and suspension force direct controller consists of a direct torque controller with a rotating speed and torque double closed loop and a suspension force direct controller with a rotor displacement and suspension force double closed loop, wherein the direct torque controller consists of two proportional plus integral (PI) controllers, a torque winding flux linkage and a torque observer, a reference flux linkage generating module and a space vector pulse width modulation module; and the suspension force direct controller consists of two proportional plus integral plus derivative (PID) controllers, a torque winding flux linkage and torque observer, a suspension force winding flux linkage observer, a suspension force estimation module, a force / flux linkage conversion module and a space vector pulse width modulation module. By the controller and the construction method, motor torque and radial suspension force are independently controlled, stable suspension and operation of a motor rotor are ensured and high motor operating performance is achieved.

The invention relates to an integrated circuit and discloses a current reference source circuit and a method for generating a current reference source. The method comprises the following steps of: generating a linear positive temperature coefficient current, a nonlinear negative temperature coefficient current and a nonlinear positive temperature coefficient current through three circuits respectively; superimposing the three currents; and taking the superimposed output currents as the current reference source. The linear positive temperature coefficient current is used for effectively offsetting linear components in the nonlinear negative temperature coefficient current, and the nonlinear positive temperature coefficient current is used for compensating residual nonlinear negative temperature coefficients, so that the sensitivity of the acquired currents to temperature changes is further reduced, and the current reference source which approximates to a zero temperature coefficient can be realized.

The invention discloses a neutral-point voltage control method of an NPC (neutral-point converter) type three-level inverter based on interval selection, belonging to the technical field of power electronics The method comprises the steps: selecting a phase which is maximum in an absolute value in the three phases as an adjusting phase, wherein a peak point of the adjusting phase is taken as a symmetrical point in the adjusting interval and the adjusting range is not greater than pi / 2; measuring the neutral-point voltage Unp in real time, comparing the Unp with a given value; determining the voltage offset amount according to the comparison result so as to adjust the modulating wave in the adjusting interval; and comparing the adjusted modulating wave with a carrier wave to output a PWM (pulse-width modulation) signal so as to control the work state of a switch tube of an inverter. With the adoption of the neutral-point voltage control method, fewer parameters are related, and only the neutral-point voltage needs to be detected, so that the method is simple in control structure and convenient to realize.

The invention provides a correction policy of current zero-crossing distortion applicable to all one-way three-phase rectifiers (including three-phase VIENNA rectifiers, three-phase bridgeless rectifiers and all star-connection cascaded three-phase rectifier topologies) based on single-period control. The policy specifically includes following steps: firstly, determining related parameters of a system, then calculating a current distortion initial point, a distortion time and a boundary condition, and finally calculating a parameter introduced compensation amount based on the above parameters.According to the policy, based on the characteristic of single-period direct current control, crossed injection is performed on the feedback of current phase-shift control signals, and superpositionis performed with an original phase-shift feedback amount so that zero-crossing distortion generated by current phase shift of the energy one-way flow three-phase rectifier is corrected without increasing the complexity of the system. According to the policy, the realization is simple, the reliability is high, an effective correction method is provided for the current zero-crossing distortion problem occurring in a single-period control process, and the application range of single-period control is extended.

The invention relates to a wind-speed and rotating-speed sensorless full-wind-speed control strategy suitable for a small and medium sized fixed propeller-pitch variable speed permanent magnet synchronous wind generator set, and belongs to a master control system in the wind power generating control technology. The control strategy provided by the invention mainly comprises firstly, maximum power tracking control in low wind-speed area; secondly, constant power control in high wind-speed area (above rated wind speed); and thirdly, constant rotating-speed soft transition control between the maximum power tracking control and the constant power control. The realization of the control strategy is based on feedback of DC bus-bar voltage signals and DC bus-bar current signals; required DC bus-bar voltage reference value is given according to the change situations of the detected DC bus-bar current, so as to achieve the purpose that output power of the generator set is controlled by controlling the rotating speed of the generator set. Therefore, wind speed and rotational speed signals are not required to be detected in the control strategy, an expensive wind-speed and rotating-speed sensor can be saved, and accordingly, the control cost is greatly reduced, and the strategy has a good application prospect in the small and medium-sized wind generator sets below megawatt class.

The invention discloses a grid fault ride-through control method for a flexible direct-current transmission system. Grid fault non-communication ride-through of the system is achieved by switching converter station control modes, direct-current side voltage is detected in real time to judge whether a grid breaks down or not, control module switching is carried out, grid fault ride-through is achieved, and a controller supporting grid fault non-communication ride-through of the flexible direct-current transmission system is formed. By optimizing an original controller with the control method, direct-current voltage is effectively controlled in a grid fault of a constant direct-current voltage side converter station when no communication exists between converter stations under the condition that no hardware circuit is additionally arranged, the converter stations still keep operating during the grid fault, and meanwhile the system can be restored to an operating state before the fault as soon as possible after the fault is removed; grid fault non-communication ride-through of the flexible direct-current transmission system is achieved on the whole, the alternating-current fault ride-through capability of flexible direct-current transmission is improved, and a good operating environment is provided for the safety and stability of the system.

The invention relates to a controller and a controlling method of a no-bearing permanent-magnetic synchronous motor. The controlling method comprises the following steps: a direct torque controller calculates magnetic linkage and a torque by torque winding magnetic linkage, a double-closing loop of a rotating speed and the torque is constructed, the increment of the phase angle of the magnetic linkage is generated by the comparing difference value of the instruction value and the real-time value of the rotating speed and the torque through double-P1 modulation, and a switch signal of an inverter of a power supply source is obtained by the modulation of SVM and a reference magnetic linkage generating module; a suspending power direct controller calculates the magnetic linkage by a winding magnetic linkage observer of the suspending power, the double-closing ring of rotor shift and the suspending power is constructed, the comparing difference value of the rotor shift generates a suspending power instruction value by PID modulation, and the switch signal of an inverter of a power supply is obtained by the rotor shift comparing difference value and the comparing difference value of the real-time value thereof after the modulation of SVM and a power / magnetic linkage converting module. The direct torque controller and the suspending power direct controller are used for forming the torque and suspending power direct controller to control the no-bearing permanent magnetic synchronous motor, and the controlling method has the advantages of simplicity and good effect.

An embodiment of the invention discloses a multiple-converter master-slave control system. The multiple-converter master-slave control system comprises a main frequency converter, a first slave frequency converter, a second slave frequency converter and N third slave frequency converters. A fourth sending port of the main frequency converter is in communication connection with a first receiving port of the first slave frequency converter; a fourth receiving port of the main frequency converter is in communication connection with a second receiving port of the second slave frequency converter; a first sending port of the first slave frequency converter is in communication connection with a second receiving port of the second slave frequency converter through the N third slave frequency converters which are connected in series, wherein N is an integer which is greater than or equal to zero. The multiple-converter master-slave control system facilitates simplifying wiring structure complexity of a converter system and improving stability and reliability of the converter system.

The invention provides a back-to-back flexible direct current transmission system and a double-loop additional frequency control method. The back-to-back flexible direct current transmission system comprises a back-to-back converter body, a basic controller, an active additional controller and a reactive additional controller, wherein the basic controller is used for enabling DC-side voltage of the back-to-back converter body, the transmitted active power and reactive power absorbed or sent to a power grid to keep constant according to an instruction of a constant active power control loop, aninstruction of a constant reactive power control loop, an instruction of a constant DC voltage control loop and an instruction of a constant AC voltage control loop; the active additional controlleris used for performing proportional-integral control on a frequency deviation input signal to output an active power additional reference instruction value; and the reactive additional controller is used for performing differential control on the frequency deviation input signal to output a reactive power additional reference instruction value. According to the invention, frequency support for a disturbed alternating current system is realized through changing the active power instruction value and the reactive power instruction value.