180results about How to "Achieve smooth switching" patented technology

The invention relates to a grid connection presynchronization control method of a microgrid inverter based on droop control. When the microgrid operates in island, as a voltage source type inverter which functions as the support in the microgrid works in accordance with droop characteristic, a microgrid voltage has a deviation from a high power grid voltage; and the problem of synchronization between the microgrid voltage and the high power grid voltage during the grid connection is the key to realize smooth switchover. The grid connection presynchronization control method provided by the invention comprises the following steps: obtaining frequency and phase position information of the high power grid voltage through a three phase software phase-locked loop (SPLL); carrying out dq (Direct Quadrate) conversion to an output voltage of the inverter based on a power grid voltage phase obtained from the locked phase; subsequently carrying out PI (Physical Impairment) regulation on a q-axis component; overlapping a synchronization angle frequency output by a PI regulator with an angle frequency generated by the droop control to be used as a reference angle frequency of the output voltage of the inverter; and finally realizing the tracking and synchronization of the output voltage of the microgrid inverter to the high power grid voltage through the closed-loop control. The impact current during the grid connection is avoided effectively.

The invention relates to a trajectory tracking control method and a control device for a driverless vehicle. The control method comprises that error of present driving trajectory and a reference trajectory of a vehicle is calculated by a data preprocessor, a target performance indicator function which is corresponding to the present driving model is obtained simultaneously; an upper layer controller predicts driving states of the vehicle over a period of time through a vehicle dynamics model; transition switch is conducted to function parameters according to switching control algorithm, and a performance indicator function at present sampling time is obtained; optimal controlled quantity of present time is calculated by considering performance requirement constraint conditions at the same time according to predicted driving states and the performance indicator function; a lower layer controller calculates throttle opening, braking pedal pressure and steering wheel turning angle according to the optimal controlled quantity; and the control device comprises the data preprocessor, the upper layer controller and the lower layer controller. Compared with the prior art, the trajectory tracking control method and the control device for the driverless vehicle have the advantages of being good in control effect, high in practicability, capable of improving stability and safety of vehicles and the like.

The invention provides a control method for page switching display and a mobile terminal. The method comprises the following steps of: acquiring a current page and a page to be switched, and loading the current page and the page to be switched into a main container; and controlling the main container on the current screen to smoothly switch and display the current page into / as the page to be switched. By the method, control of a motion component on multi-page display can be realized by setting the main container capable of accommodating a plurality of pages, so that the animation effect of multi-page smooth transition is realized.

The invention relates to a double-port stable control method and circuit and a bidirectional DC / DC power converter, and belongs to the technical field of power converters. A controller of the controlcircuit provides a PWM control signal, a driving circuit is controlled to switch on or switch off a corresponding MOS in a switch tube power circuit, and a DC bus voltage VBus in certain stability andprecision is formed between the two ends of a DC bus side capacitor C via a DC bus side filtering circuit. The controller controls the driving circuit by carrying out under-voltage protection of an energy-storage unit when the voltage in the energy storage side is lower than the lower limit of the working voltage; carrying out overvoltage protection of the energy-storage unit when the voltage inthe energy storage side is higher than the upper limit of the working voltage; and limiting the maximal continuous charging / discharging current of the energy-storage unit via an ACM control algorithmwhen the voltage in the energy storage side is within the upper limit and the lower limit of the working voltage. PWM output control is combined with ACM control to realize double-port stable controlof the bidirectional DC / DC power converter, and the method and circuit are suitable for any type of bidirectional DC / DC power converter.

The invention discloses a smooth switching control method for a three-phase dual-mode inverter. The method comprises off-grid and grid-connected smooth switching control and off-grid smooth switching control. Smooth control comprises soft start of virtual impedance and monocycle current feedback control. When the inverter is switched to the grid-connected mode from the off-grid mode, output current phase lead control and smooth switching control are conducted, temporary impact of output currents and in-network currents of the inverter are restrained, and then backward flowing of energy of the inverter is greatly reduced, and grid-connected smooth switching is achieved. When the inverter is switched to the off-grid mode from the grid-connected mode, only monocycle current feedback control is conducted, the in-network currents are reduced to zero quickly, DC side voltage fluctuation of the inverter caused by temporary unbalance of the currents is avoided, and off-grid smooth switching is achieved. According to the method, the problems that current impact is large when the micro-grid inverter is connected to the grid and DC side voltage fluctuates when the inverter is off-grid are solved, and smooth switching of the operation modes of the micro-grid is achieved.

The invention discloses a providing method of a payment service on a wireless terminal and relevant equipment and a system thereof. The providing method of the payment service on the wireless terminal and the relevant equipment and the system thereof are used for achieving smooth switching of application and payment on the wireless terminal. The providing method comprises that when an application service module on the wireless terminal receives payment requests, a safe payment service client end is called; the safe payment service client end generates a payment order to be submitted to a safe payment service server to display a trade information interface to a user, after the confirmation order of trade information sent by the user is received, and the user confirmation information is submitted to the safe payment service server so as to display a trade result interface to the user; and after the safe payment service server client end receives the trade result confirmation order sent by the user, the application service module is called back.

The invention belongs to the technical field of power electronic application, and especially relates to a wide-input direct current inverter topology and a feedforward average current control method thereof. The wide-input direct current inverter topology comprises a two-transistor Buck-Boost inverter and an interleaved two-transistor Buck-Boost inverter. The feedforward average current control method applicable to the wide-input direct current inverter topology is composed of an input voltage feedforward module, a mode switching module, a voltage outer ring and a current inner ring. According to the method, input voltage feedforward is introduced into the current inner ring in average current control, a feedforward function from the input voltage feedforward to the current inner ring is computed, simplification is carried out, thereby obtaining feedforward average current control applicable to practical application, and the input dynamic response performance of the inverters in a whole input voltage range is greatly improved; and moreover, by adoption of an interleaving technology, the conversion capacity is increased, the output current ripple is effectively reduced, and the support is provided for the field with wide range input and high power conversion.

The invention discloses a clock switching method and device. The method comprises the following steps: firstly processing a clock selection signal to generate a first clock selection signal and a second clock selection signal, wherein when the clock selection signal transfers into a strobe clk2 state from a strobe clk1 state, the first clock selection signal transfers at the time of keeping at least one clk1 impulse of the strobe clk1 state; and the second clock selection signal transfers at the time of keeping at least two clk2 impulses of the existing blocking-up clk2 state after the first clock selection signal transfers; then taking the first and second clock selection signals as gating enable signals so as to respectively perform gating processing on the clk1 and the clk2; and finally outputting signals generated by the gating processing in a combination mode. In the invention, although the clock selection signals change at any time, burrs of an output clock do not generate, thus realizing smooth switching among clocks with any frequencies.

The embodiment of the invention provides an encoding mode switching method which comprises the steps that when the i frame and the i+1 frame are in the MDCT encoding mode and the ACELP encoding mode, the MDCT encoding mode is carried out on the i frame through a pre-defined window pattern to obtain MDCT encoding information; encoding information of the i frame or the i frame and frames before the i frame are decoded to obtain decoding signals; according to the decoding signals, partial input signals of the i frame and partial input signals of the i+1 frame, history states of a filter in the ACELP encoding mode are set up and updated, and then subsequent input signals which are one frame long are subjected to the ACELP encoding process. The embodiment of the invention provides an encoding mode switching device from MDCT to ACELP, and a decoding mode switching method and device from MDCT to ACELP, and further provides an encoding mode switching method from ACELP to MDCT and a decoding mode switching method and device from ACELP to MDCT.

The invention discloses a wide-gain control method for an LLC resonant converter and the resonant converter. The method comprises the steps of: employing a full-bridge LLC PFM control mode at a low-voltage segment of an input voltage range, and changing an output voltage gain through changing a switching frequency; adopting a full-bridge LLC PWM phase shift control mode in a medium-voltage sectionof an input voltage range, wherein in the whole medium-voltage section range, the switching frequency fsw is equal to the resonant frequency fr0, and the output voltage gain is changed by changing the phase shift angle [theta]; in a high-voltage section of an input voltage range, adopting a full-bridge LLC variable duty ratio control mode, wherein in the whole high-voltage section range, the switching frequency fsw is equal to the resonant frequency fr0, and the output voltage gain is changed by changing the duty ratio of a primary side first switching tube S1. According to the invention, smooth switching between modes is achieved, the working efficiency, the gain range and the power density of the converter are improved, and the requirements of a wide-voltage gain range conversion occasion are met.

The invention discloses a communication terminal and a user card switching method thereof. The communication terminal at least supports two user cards, all user cards are at least corresponding to two network modes, and at least one first user card, among all the user cards, supports standby in two or more than two network modes; the communication terminal comprises each baseband module corresponding to each network mode, and at least one first baseband module, among all the baseband modules, support standby of two or more than two user cards in a network mode corresponding to the baseband module; and the communication terminal further comprises an application module, and the application module comprises a control unit which is suitable for outputting a control signal when it is detected that a switching condition is satisfied and a switching unit which is suitable for switching the baseband module communicating with the first user card between the first baseband module and other baseband modules under the control of the control signal. The technical scheme can realize smooth switching among user cards, improves network finding efficiency during switching, and reduces influences on normal services.

The invention belongs to the technical field of televisions and particularly relates to a video playing method, device and television. The method comprises the steps that a video receiver obtains a current video playing state; when the obtained video playing state is a live state and a state switching indication is received, the live state is switched to a video-on-demand state; after the live state is switched to the video-on-demand state, video-on-demand data cached in a new video cache zone in advance are called to be played. According to the video playing method, device and television, the problems that a user needs to carry out multiple complex steps of manual operation when live video and video-on-demand video are switched, and video switching smooth degree is low are solved, so that smooth switching of the live video and the video-on-demand video on the intelligent television is achieved, and the shortcomings of a black screen, flickering, sticking and the like in a hardware switching process are overcome.

The invention relates to a hip joint mechanism of an underactuated biped walking robot, which can conveniently realize the smooth switch of an on-line driving state and an off-line no-driving state and is beneficial to the high-efficiency walking control of the underactuated biped walking robot. The technical proposal is as follows: an angular bisector mechanism (1) which consists of two sets of positive and reversed gear-chain groups and a free transmission shaft (9) leads the rotational motions of the two legs around the hip joints to be linked with the motion of the upper body, and limits the upper body at the angular bisector of the two legs; a hip joint device mounting plate (2) is fixed with the upper body of the robot; a bidirectional drive system (3) consists of two sets of driving motors which finally convert the output moment of a motor into the relative moment between the two legs, a transmission shaft and a steel rope; and an incomplete gear transmission system (4) comprises a driving motor (13) as well as a reducer and an incomplete driver gear (12) which are arranged on the output shaft of the driving motor.

The invention provides a video signal switching system and a video signal switching method. The system comprises a receiving module, a detecting module and a switching module, wherein the receiving module is used for receiving a command of switching a currently displayed first video signal to a second video signal, and sending a message according to the command; the detecting module is used for detecting whether the first video signal reaches a vertical blanking period according to the message, and if the detected first video signal reaches the vertical blanking period, the detecting module sends a switching command; and the switching module is used for switching the first video signal to the second video signal according to the switching command.

The invention relates to the field of mechanical arms of foot type robots, in particular to an inverse multi-solution selection and time optimal trajectory planning algorithm of a mechanical arm. According to the algorithm, the most appropriate group of solutions can be rapidly selected from multiple inverse solutions according to the current pose of the mechanical arm, so that singular patterns are effectively avoided, smooth switching between different inverse solutions is achieved, and continuity and non-oscillation of control and action of the mechanical arm are guaranteed; and a trajectory with optimal time is planned by using a trajectory planning method combining a heptatic polynomial and conditional proportional control, so that smooth, continuous and derivable joint angles, angular velocities, angular accelerations and angular jerk are ensured; and meanwhile, multi-target and multi-constraint conditions are met, and the specification of an actuator is met; and the constraint condition comprise joint angular velocity maximum value constraint or joint angular acceleration maximum value constraint, and the like. According to the algorithm, the calculation amount of multi-solution selection and trajectory planning is greatly reduced, real-time and efficient time optimal trajectory planning can be realized, and the algorithm can be popularized and applied to a low-calculation-power controller.

The invention discloses a distributed-generation three-phase inverter smooth switch control method. The method includes smooth switch control over two parts from isolated island operation to grid-connected operation and from the grid-connected operation to the isolated island operation. A smooth switch control link is mainly composed of a phase-locked loop (PLL) and a switch. When an inverter is switched from the isolated island operation to the grid-connected operation, output voltage of the inverter is subjected to presynchronization by operating the switch, so that the output voltage and grid voltage of the inverter are synchronized, current impacting during grid connection is reduced, and smooth grid connection switch is realized; when the inverter is switched from the grid-connected operation to the isolated island operation, reference instruction controlled by current are gradually decreased to zero form current instruction current by operating the switch, off-grid operations have no effect on a system since the grid-connection current is dropped to zero before disconnection of the grid connection switch, the output voltage of the inverter cannot fluctuate, and off-grid smooth switch is realized. With the method, dual-mode smooth switch operation of the distributed generation system is realized.

The invention discloses a control method for smooth handoff of a micro grid operation mode based on a DG ad-hoc network strategy, which comprises the following steps: when the operation mode of the micro grid is changed from a grid-connected mode into an isolated island operation mode, according to the condition that whether a distributed power source DG can perform isolated island operation, the micro grid is split into a plurality of DG local ad-hoc networks capable of performing independent operation, and continue power supply to the important load or the local load is ensured through the DG local ad-hoc networks; after each DG local ad-hoc network is stabilized, outward search is performed and the power supply range is enlarged, so that DG dynamic ad-hoc networks are formed; after all the DG dynamic ad-hoc networks are stabilized, the DG dynamic ad-hoc networks which satisfy interconnection requirements are sequentially subjected to network interconnection for operation by taking the DG dynamic ad-hoc network including a micro grid main power source as the center; after power supply of a public power distribution network recovers, all the DG dynamic ad-hoc networks are grid-connected with the public power distribution network for operation. According to the control method, the DG local ad-hoc networks ensure the continue power supply to the important load of the micro grid; the power supply is recovered to power-losing areas continuously through the DG dynamic ad-hoc networks, favorable conditions are provided for the operation mode, which is changed from the isolated island operation mode into the grid-connection operation mode, of the micro grid, and the smooth hand-off of the micro grid operation mode is ensured.

The invention relates to a nonlinear strict-feedback system and global finite-time neural network control method, belongs to the field of nonlinear system control and the field of neural network control, and is used for solving a problem of nonlinear strict-feedback system and global neural network control with unknown dynamics. The method is based on a backstepping framework; a switching mechanism is introduced to implement switching between neural network control in an active approximation domain and robust control outside the approximation domain; meanwhile, a neural network weight is updated on the basis of a tracking error and a modeling error; learning performance of a neural network is improved; on the basis, a robust design scheme is given out; finite-time convergence of the systemtracking error can be implemented. According to the invention, one type of strict-feedback system and neural network control with unknown dynamics is guaranteed to always work in the active approximation domain, global stability of a closed-loop system can be implemented, learning performance of the neural network for unknown dynamics is improved, and the performance requirement of the actual control problem is ensured.

The present invention relates to an aircraft global finite time neural network control method based on a switching mechanism, belonging to the field of aircraft control. The problem of aircraft globalfinite time neural network control is solved. The method comprises the steps of: decoupling an aircraft vertical model to a height subsystem and a speed subsystem, employing backstepping control forthe height subsystem, and employing PID control for the speed subsystem. For the height subsystem, a switching mechanism is introduced to achieve switching between an effective approaching intra-areaneural network control and approaching outer-area robust control, and based on the tracking errors and the modeling errors, performing updating of the neural network weight so as to improve the learning performance of the neural network, and giving a robust design scheme on this basis, achieving finite time convergence of the tracking errors of the system. The aircraft global finite time neural network control method ensures that the aircraft neural network control is still worked in the effective approaching area to achieve the global stability of the closed-loop system and ensure the performance demand of the practical engineering application.

The disclosed pattern matching method comprises: concentralized controlling and transmitting data to the database, user and some engines; when user receiving message, selecting one pattern matching engine according set strategy, and sending message to the selected engine; according to pattern matching rule stored in database, matching pattern; returning matching result to user, and executing pre-set process to the message. This invention reduces system complexity, and realizes smooth switch and uniform control management for multiple matching engines.

The invention provides a control apparatus and control method for maintaining stable voltage of a conflux DC bus in a distributed power generation system. In order to enable the current transformers of multiple power generation devices to realize parallel operation under the condition that there is no interconnection line communication, voltage instruction signals are obtained through calculation according to a preset sagging characteristic by actual output currents, current instruction signals are given according to actual conditions by an MPPT algorithm or a system, two control signals obtained through operation of a voltage control loop and a current control loop are sent to the minimum taking link of CPU control software, and the output of the link is used for PWM to ensure no overvoltage in case of a current control mode and ensure no overcurrent in case of a voltage control mode, such that smooth switching of multiple electric power converting devices between the current control mode and the voltage control mode is realized, and under the condition that there are no interconnection communication lines, multiple converters can realize stable parallel output according to power which can be obtained by themselves.

The invention provides a method for realizing the uninterrupted communication when the trunk gateway disaster tolerance occurs, as well as a system and media gateways thereof. The method comprises the following steps: after a first media gateway detects that a first link between the first media gateway and a first soft switch device is disconnected, the first media gateway can provide protection for the existing speech channel of the trunk gateway users and send the transmission-prohibited message to the end office; and after the end office receives the transmission-prohibited message, all the recent incoming calls are routed to a second media gateway. According to the method, the reliability and the disaster tolerance capacity of the network system can be improved, and the satisfaction degree of clients can be enhanced.

The invention provides an off-grid and grid-connected smooth switching method of a virtual synchronous generator. The smooth switching method is characterized by comprising grid-connected / off-grid and off-grid / grid-connected smooth switching. As for off-grid / grid-connected switching, the switching strategy is added in the off-grid and grid-connected switching process without modifying the control strategy of the virtual synchronous generator, and the reference voltage of the virtual synchronous generator is changed into the command reference voltage from the grid voltage and the correction angular velocity of pre-synchronous control is enabled to be zero directly so as to realize grid-connected / off-grid smooth switching. Popularization of the virtual synchronous generator technology is further facilitated in the field of new energy power generation, and friendly accessing of distributed energy resources can be realized so as to enhance the stability of the electric power system. Besides, application of the control strategy and the theoretical analysis method related to the conventional synchronous generator to VSG is facilitated so as to play an important role in the active power distribution network and the microgrid in the future.

The embodiment of the invention relates to a control method and device which are applied to BUCK-BOOST topology. The method concretely comprises the following steps: processing topological output signal to obtain a pulse width modulation signal; performing OR operation on the pulse width modulation signal and a first modulation signal to obtain a first control signal so as to control the state of a first transistor of the topology; performing AND operation on the pulse width modulation signal and a second modulation signal to obtain a second control signal so as to control the state of a second transistor of the topology. Therefore, the method realizes three topological states and smooth handover, and simultaneously the control circuit is relatively simple; and the control range is enlarged and the control precision is improved.

The invention relates to a virtual synchronous machine seamless smooth switching method and system. A current loop input reference value controlled by PQ before switching on the output side of a converter station is calculated; the current loop input reference value controlled by the PQ is taken as an initial value and substituted into a pre-established circuit simulator model to calculate a current loop input reference value controlled by virtual synchronous machine technology (VSG); and based on the current loop input reference value controlled by the PQ and the current loop input referencevalue controlled by the virtual synchronous machine technology (VSG), a corresponding switching action is performed according to a pre-set control switching instruction. The virtual synchronous machine seamless smooth switching method and system applies PQ control and VSG control to a grid-connected dual-mode converter station control system, the deviation between the amplitude and phase of outputvoltage when switching between two control modes is eliminated through a designed simulator model and relevant operations, and smooth switching of control modes is realized.

The invention discloses a starting method for a brushless direct-current excitation synchronous motor. The method includes the following steps of: S1, asynchronous starting closed-loop vector control process: three-phase reference voltage Va, Vb and Vc can be obtained according to three-phase stator current Ia, Ib and Ic of the synchronous motor, and the three-phase reference voltage Va, Vb and Vc c are subjected to pulse-width modulation and are outputted to stator windings of the synchronous motor so as to perform excitation; S2: transition closed-loop vector control process: when the rotation speed of the synchronous motor achieves preset rotation speed, excitation provided by the stator windings is gradually switched to excitation provided by a brushless direct-current excitation device; and S3: synchronous closed-loop control process: when all excitation is switched to excitation provided by the brushless direct-current excitation device, the synchronous motor enters a synchronous operation process. The starting method for the brushless direct-current excitation synchronous motor of the invention has the advantages of simple control, low starting current, excellent speed adjusting performance and high starting torque.

The invention discloses a pure electric vehicle running working condition judging system. The system comprises a signal acquisition module, a judgment decision module and a signal output module. The signal acquisition module is responsible for acquiring vehicle state signals and transmitting the vehicle state signals to the judgment decision-making module; the judgment decision module is responsible for processing the received vehicle state signals, judging running working condition information of a vehicle, and transmitting the information to the signal output module; the signal output module is used for outputting the running working condition information of the vehicle to a whole vehicle controller; the whole vehicle controller controls the vehicle to run in a corresponding state according to the received signals. By the adoption of the pure electric automobile running working condition judging system, switching between vehicle running working conditions can be smoother, the judgment logic is more reasonable, the intention of a driver can be reflected more accurately, and universality and reusability are better.

The invention relates to a sensorless control method and device of a permanent magnet synchronous motor of an electromobile EHPS (electric hydraulic power steering system). The control method dependson a permanent magnet synchronous motor DC / AC controller; for a demand of the electromobile EHPS, the controller realizes real-time estimation on the rotor location and speed of the permanent magnet synchronous motor by utilizing the control method of the multi-algorithm fused sensorless, thereby realizing the reliable control on the permanent magnet synchronous motor full rotating speed range ofthe EHPS; the controller can realize the current voltage detection, the external communication, high-voltage inversion and like functions, and external interfaces with high-low voltage supply, AC output, enabling signal and communication line; the controller is conducive to an assisting motor for the EHPS without installing a sensor, the system cost can be reduced, the system complexity is lowered, and the system reliability is improved. Furthermore, the controller can properly reduce the power-assisted steering when the vehicle speed is high, the road feel is improved, and the driving stability of the vehicle is improved.

The invention discloses a dual three-phase motor minimum harmonic injection over-modulation strategy and a carrier wave realization method thereof. The specific method comprises the steps of introducing the concept of a middle vector, performing analysis on a harmonic voltage which needs to be injected into an over-modulation region harmonic sub plane based on a space voltage vector algorithm, andproposing a minimum harmonic injection strategy of the dual three-phase motor over-modulation region, so that the harmonic current in the over-modulation region is reduced to the maximum degree; andspecific to the problems of asymmetrical pulse width modulation waveform, relatively high switching loss and the like of the six-phase inverter four-vector space voltage vector algorithm, a linear modulation region algorithm and an over-modulation region algorithm are unified into a carrier wave-based dual zero sequence injection pulse width modulation strategy to be realized, so that smooth switching between the linear modulation region and the over-modulation region can be realized. The problems of blank of the minimum harmonic injection technology and a complex SVPWM-based realization process in the prior art are solved.

The invention discloses a current feed forward-voltage feedback flux weakening control method for an electromobile permanent magnet synchronous motor. The current signals of the built-in electromobilepermanent magnet synchronous motor are collected, and the conversion of coordinates is carried out to obtain stator current direct-axis component and stator current quadrature-axis component; voltagesignals are collected to obtain voltage source inverter direct current bus voltage; rotary transformer signals on the built-in permanent magnet synchronous motor are collected, and the rotor positionangle and mechanical rotating speed of the motor are obtained through calculation; and a blurry PI feedback link is added on the basis of a traditional formula computing method. For the purpose thatthe motor is smoothly and stably switched in a constant torque region and a constant power region, a smooth switching method based on a weighting function is proposed. The method disclosed by the invention is simple and practicable, the dynamic performance of the motor in the constant power region can be improved effectively, the method has relatively high parameter robustness, and the method canbe smoothly and stably switched in the constant torque region and the constant power region.