262results about How to "Realize decoupling control" patented technology

The invention discloses a permanent magnet biased bearingless switched reluctance motor, which comprises stator back yokes, permanent magnets, stator suspension cores, stator torque cores, magnetic shields, suspension winding coils, torque winding coils, rotor cores and a shaft, wherein the stator suspension cores are wound with the suspension winding coils; the stator back yokes are arranged outside the stator suspension cores and connected with the stator suspension cores; the permanent magnets are arranged between the two stator back yokes; the magnetic shields and the stator torque cores are arranged in stator suspension core slots; the magnetic shields are positioned between the suspension stator windings and the stator torque cores; the rotor cores are arranged in the stator suspension cores and the stator torque cores; gas are reserved between the rotor cores and each of the stator suspension cores and the stator torque cores to form air gaps; and the shaft is arranged in the rotor cores. By the permanent magnet biased bearingless switched reluctance motor, decoupling control over torque and suspending power is realized to bring convenience to high-speed running; and a suspension biased magnetic flux is provided by the permanent magnets to reduce suspension power consumption and improve the efficiency of the motor.

This invention relates to permanent simultaneous motor control system based on NN with five free degree and with no bearing, which is characterized by the following: one two-free degree with no bearing simultaneous motor, one three-free degree alternating radium and axis direction mixed magnetic bearing form one sample body; three Clark anti-conversion, three current tracing anti-converter and one linear power amplifier, sample machine and its load work as one integration to form compound controlled subject; using static NN summer through study formula to form NN reverse for non-linear dynamic decoupling control on five free degrees bearing.

The invention provides a gesture-adjustable coordinate decoupling robot with seven degrees of freedom. The robot comprises an Z-axis vertical lifting module, an X-axis horizontal moving module, a Y-axis horizontal moving module, a gesture adjusting module and a tool moving module which are successively connected. The robot comprises degrees of freedom of Z, X, Y, alpha, belt and gamma and L straight line degree of freedom. For degrees of freedom disposition, a redundancy control method is provided, where the gesture can be adjusted in advance and the coordinates are then fully decoupled. The control method comprises the following steps: firstly adjusting three rotating gestures of a tool to a certain angle; and then controlling the other four degrees of freedom, wherein the tail end of the tool reaches a certain position, that is, on the premise of maintaining the tool in a certain unchanged angle, the tail end of the tool is easy to reach a certain coordinate position, so that gesture angle control and coordinate position control are decoupled. According to the robot provided by the invention, the redundancy f the system is increased, and the robot is convenient to operate and control, and has a wide application prospect in special application environments such as industries, medical treatment and services.

The invention discloses a bionic cockroach robot based on a double-four link mechanism; the robot comprises six groups of the same feet, and upper connecting plates and lower connecting plates used for connecting the feet together. The configuration of the feet adopts the double-four link mechanism, and three steering gears drive the double-four link mechanism to respectively simulate the motion of the hip, thigh and calf joints of a cockroach. The bionic cockroach robot advances in a tripod gait way so as to realize the tripod gait motion. In order to improve the bearing capability of the robot and simultaneously put the three steering gears on the feet so as to improve the rigidity and the stability of the whole robot, the invention uses the plane four-link mechanism in the design of the configuration of the feet, can achieve the amplification of force and motion, reduce the requirements on the driving capability of the steering gears, and improves the load capability of the robot. From the perspective of bionics, the bionic cockroach robot which adopts the multi-link structural design is reasonable.

The present invention discloses a method and system for intelligent driving horizontal and vertical decoupling control of a great inertia electric motor coach. The method comprises the following steps: the step 1: establishing a coordinate system and setting an expected track and an expected speed according to a vehicle; the step 2: calculating an expected front-wheel course angle through a preview model; the step 3: calculating the real0-time front-wheel course angle of the vehicle; the step 4: calculating the estimated course angle of the vehicle; the step 5: calculating the course deviation and calculating the controlled quantity of a steering wheel according to the control rate; the step 6: calculating a vertical controller driving speed and a braking deceleration; and the step 7: inputting the controlled quantity into an execution mechanism to realize response control. The method for the intelligent driving horizontal and vertical decoupling control of the great inertia electric motor coach improves the control precision of tracking the expected track of the great inertia electric motor coach in the driverless environment, optimizes the control structure, effectively overcome the great inertia and the hysteresis quality and improve the response speed and the tracking effect of the control of the great inertia unmanned coach.

The invention discloses an automatic load-variable multi-variable control method for an air separation device. According to the method, a module 1, namely a gain scheduling module, a module 2, namely a dynamic multi-variable model prediction control module, and a module 3, namely a process real-time optimization module are involved. The method comprises the following steps that: the module 3 calculates the optimal steady state value of a process variable related to load change according to the load-variable requirement of the device and sends the optimal steady state value to the module 2; the module 1 determines a prediction model adopted by a controller of the module 2 at the moment according to the current value of a scheduling variable; and the module 2 gradually pushes the device to the optimal steady state working point which is calculated by the module 3 on the premise of ensuring product quality and not going against equipment constraints. By the method, the problems of mutual decoupling of energy and a material, nonlinear control and the like in the wide-range load-variable process of the air separation device can be radically solved, smooth and quick transition among different working conditions is realized, and the load-variable operation quality and speed of the air separation device are ensured.

The invention discloses a variable speed-variable pitch combined control method of a variable speed constant-frequency wind turbine generator. According to the control method, an optimal rotating speed estimated value and a rotating speed reference value are introduced to respectively serve as reference quantities of rotating speed control and variable pitch control. A rotating speed PID controller performs torque command regulation according to the deviation of the optimal rotating speed estimated value and the rated rotating speed of the wind turbine generator, a variable pitch PID controller performs pitch angle command regulation according to the deviation of the rotating speed reference value and the rated rotating speed of the wind turbine generator, decoupling control between rotating speed control and variable pitch control is achieved, and interference between rotating speed control and variable pitch control is avoided. When wind speed fluctuates nearby the rated value and pneumatic power captured by the wind turbine generator is larger than rated power, the rotating speed reference value corresponding to a pneumatic power estimated value is larger than the rated rotating speed of the wind turbine generator, the variable pitch PID controller regulates a pitch angle command before a torque command output by the rotating speed PID controller reaches the rated value, and variable speed-variable pitch combined control is achieved in advance to control rotating speed of the wind turbine generator and overshooting of output power.

The invention provides a biological fermentation adaptive control system and a control method based on neural network inverse. The control method comprises the following steps: constructing the neural network inverse by using a neural network and a time division multiplexing time delay link, enabling the neural network to achieve an inverse system function of a biological fermentation system by adjusting the weight coefficient of the neural network, connecting the neural network inverse and the biological fermentation system in series to form a pseudo-linear compound system, decoupling the pseudo-linear compound system in a linearization mode into two pseudo-linear subsystems with single input and single output, presetting desired signals, according to the control inputs of each pseudo-linear subsystem and the outputs of the biological fermentation system of current time and prior moment, constantly renewing the parameters of a model-free adaptive controller and the control input of each pseudo-linear subsystem of the following moment, enabling the outputs of the biological fermentation system to follow the preset desired signals effectively, thereby achieving the model-free adaptive control of the biological fermentation system, and improving the control performance of a biological fermentation process.

The invention discloses a short-circuit fault-tolerant vector control method for an embedded hybrid magnetic material fault-tolerant cylindrical linear motor. The short-circuit fault-tolerant vector control method comprises the following steps: building a five-phase embedded hybrid magnetic material fault-tolerant cylindrical linear motor model; compensating normal thrust missing caused by a short-circuit fault phase and suppressing a thrust ripple caused by phase short-circuit current with non-fault phase current of the motor; and obtaining expected phase voltage by adopting a series of coordinate conversion and voltage feed-forward compensation strategies, and achieving a fault-tolerant vector control after the phase short-circuit fault of the motor by a zero-sequence voltage harmonic injection-based CPWM modulation mode. According to the short-circuit fault-tolerant vector control method, the motor can suppress the thrust ripple of the motor under the condition of a phase short-circuit fault-tolerant operation; more importantly, the dynamic property, the steady-state performance and the properties in a normal state are consistent; the switching frequency of a voltage source inverter is constant; a CPU is low in overhead; and a natural coordinate system only needs to counterclockwise rotate a certain angle in any phase short-circuit fault, so that the motor fault-tolerant operation can be achieved.

The invention provides an excitation control device of a brushless doubly-fed motor independent power generation system and belongs to a power generation control device for a brushless doubly-fed motor. According to the technical scheme of the invention, the defects in the prior art that, an existing scalar control method is poor in dynamic performance and a conventional bisynchronous rotating reference frame is complicated in vector control, high in cost and low in efficiency can be overcome. According to the technical scheme of the invention, the device comprises a PW voltage magnitude controller, a PW voltage frequency controller, a CW current vector controller, an LC filter, a rotating speed calculator, a CW current frequency feed-forward amount calculator, a PW voltage phase-locked loop and a PW current converter. The CW current vector controller of a brushless doubly-fed motor is adopted as an inner ring, while the PW voltage magnitude controller and the PW voltage frequency controller of the brushless doubly-fed motor are adopted as an outer ring. In this way, the PW voltage magnitude and the PW voltage frequency are independently controlled. Meanwhile, a cross feed-forward compensation mechanism is adopted in the CW current vector controller, so that the device is faster in response rate and better in stability precision. The constant-frequency and constant-voltage generating function of the brushless doubly-fed motor independent power generation system in the speed-varying and load-varying condition is realized.

The invention discloses a construction method for an automatic disturbance rejection controller of a three-motor synchronous control system, which comprises the following steps that: three controlled induction machines, three transducers and a common load are used as a whole to form a three-motor synchronous control system; and a speed control circuit and two tension control circuits of the three-motor synchronous control system are provided with an optimized first-order automatic disturbance rejection controller respectively, wherein the optimized first-order automatic disturbance rejection controller is a device for determining a new controlled quantity according to a system setting, system controlled output and a previous controlled quantity; the optimized first-order automatic disturbance rejection controller and the three-motor synchronous control system form a closes loop; and the optimized first-order automatic disturbance rejection controller consists of an extended state observer, a proportional controller and has a disturbance estimated value for making up an error feedback controlled quantity. The method has the advantages of simple algorithm, easily adjusted parameters, better decoupling control between the speed and the two tensile forces independent of an accurate mathematical model of an alternating current machine, higher response speed, higher static accuracy, higher capacity of resisting disturbance and higher robustness.

The invention discloses a motion-decoupling XY-direction precise locating platform which comprises a first and a second voice coil linear motors, a first and a second coupling flanges, a first and a second linear bearing assemblies, a working platform and a support platform component, wherein, the first and the second voice coil linear motors are respectively connected with the working platform via the first coupling flange and the first linear bearing assembly as well as the second coupling flange and the second linear bearing assembly in an orthogonal manner; the first voice coil linear motor is connected with the first coupling flange; the first coupling flange is connected with the first bearing body of the first linear bearing assembly; the first bearing pedestal of the first linear bearing assembly is connected with the working platform; the second voice coil linear motor is connected with the second coupling flange; the second coupling flange is connected with the second bearing body of the second linear bearing assembly; the second bearing pedestal of the second linear bearing assembly is connected with the working platform; the working platform is supported by the support platform component; and the support platform component and the first and the second voice coil linear motors are arranged on the base.

The invention discloses a method of forming a distributed energy storage system by a small hydropower cluster. The method comprises steps: a total net load value PLj(t) of all small hydropower stations at a tth time in an energy storage cycle T is acquired; according to an optimization objective, the total net load value PLj(t) and planned load pi(t) of an ith small hydropower station, the actual load pfci(t) of the ith small hydropower station is acquired; and according to the actual load pfci(t) of the ith small hydropower station, optimal efficiency control is carried out on a water pumping and water storing device of the ith small hydropower station, and the ith small hydropower station is made to operate under the optimal efficiency according to the actual load pfci(t), wherein the water pumping and water storing device is a hydraulic turbine, a water pump or a reversible hydraulic turbine. Through carrying out improvement on the small hydropower stations and using an energy management unit to manage the small hydropower stations in a unified mode, the multiple small hydropower stations can form a large energy storage system capable of power generation and energy storage, the problems of the operation efficiency and the utilization of the small hydropower stations can be solved, and the regulation capability of the power grid is improved.

The invention discloses a reactive power synergic control method and system of a large-scale energy storage participating in new energy field station. According to the method, an energy storage converter is divided to active power synergic control group and a reactive power synergic control group, wherein the active power synergic control group is in a way that an active power is controlled with full capacity, smooth wind light output is performed and an active power target value of the full station is traced, and the reactive power synergic control group is in a way that a reactive power is controlled with full capacity, a reactive power voltage demand of a grid-connected point is traced, and reactive power standby of each reactive power source in the new energy field station is optimized. By the method, active power and reactive power decoupling control of large-scale energy storage under different control periods is achieved, the influence of active power and reactive power simultaneous control of an energy storage converter on stability and accuracy of active power control can be prevented, the smooth wind light output fluctuation of the energy storage is achieved, the influence of active power fluctuation on a voltage of the grid-connected point is reduced, the reactive power target control of the energy storage participating in tracing the voltage of the grid-connected point is also achieved, enough reactive power standby is reserved, and the grid-connected running stability of new energy power generation is improved.

The invention discloses a diesel engine full-dimension SCR catalytic reactor performance test platform based on tail gas simulation. A conventional full-dimensional SCR catalytic reactor performance test method based on diesel engine stand is high in cost, complex in process, poor in repeatability and long in period. An air supply system provides tail gas flow required for air speed test, a combustion heating system controls the tail gas temperature, a mixed charging system completes standard gas injection of key tail gas components and tail gas fully mixing, a urea injection system simulates an actual SCR system reducing agent adding process, and a signal acquisition and control system monitors the entire test platform and analyzes the performance of full-dimension SCR catalytic reactor under different test conditions. The full-dimension SCR catalytic reactor performance test platform can replace a diesel engine performance testing stand, and can comprehensively test and analyze the temperature characteristics, the ammonia-nitrogen ratio characteristics, air speed characteristics and pressure drop characteristics of a full-dimension SCR catalytic reactor for post-treatment of a diesel engine by simulating the tail gas flow, tail gas temperature and key tail gas components of the diesel engine.

The invention discloses an active filtering three-phase and four-wire system type photovoltaic grid-connected system and a method. The active filtering three-phase and four-wire system type photovoltaic grid-connected system comprises a DC / DC boost circuit and a DC / AC inverter circuit, wherein the DC / DC boost circuit and the DC / AC inverter circuit are connected in series to form a circuit of a topological structure of the active filtering three-phase and four-wire system type photovoltaic grid-connected system and the decoupling control strategy is conducted on the zero-sequence current of the circuit. The DC / DC boost circuit is used for tracking a maximum power point for photovoltaic power generation. The control of the DC / AC inverter circuit is realized by an electric current loop and an electric voltage loop, wherein the decoupling control strategy is conducted on the zero-sequence current of the electric current loop and the proportion integral (PI) control strategy is conducted on the electric voltage loop. By means of the PI-controlled electric voltage loop, the voltage of a DC bus of an inverter system can be stably controlled and a photovoltaic active current reference value is generated. The method comprises three steps, namely the generation of a reference current, the decoupling control of the zero-sequence current of the electric current loop based on a Dq coordinate system, and the synthesis of a reference voltage and the pulse width modulation. According to the technical scheme of the invention, by means of the electric current loop with the zero-sequence current thereof subjected to decoupling control, not only the output of the photovoltaic active current is tracked and controlled, but also the harmonic current and the zero-sequence current of a neutral line are tracked and compensated. Therefore, the functions of photovoltaic power generation and unbalanced current compensation are realized at the same time.

The invention discloses an embedded type mixing magnetic material fault-tolerant cylindrical linear motor which comprises primary bodies and secondary bodies. The length of each primary body is smaller than that of each secondary body. An air gap is reserved between each primary body and the corresponding secondary body. Each primary body comprises armature teeth, fault-tolerant teeth and a coil winding. The 2*m armature teeth and the 2*m fault-tolerant teeth are uniformly distributed on each primary body, wherein m is the phase number of the motor and is larger than or equal to three; the armature teeth and the fault-tolerant teeth are arranged at intervals in a staggered mode. Only one set of disc-shaped coil windings are placed into an armature tooth groove of each primary body. No windings are arranged on the fault-tolerant teeth. The secondary bodies of the motor are made of mixing magnetic materials, a part of ferrite is used for replacing a part of rare earth permanent magnets to form four different mixing magnetic material structures, on one hand, the quantity of the adopted rare earth permanent magnets is greatly reduced, and the cost of the motor is reduced; on the other hand, as the magnetic energy product of the permanent magnets is reduced, the eddy-current loss of the motor is reduced greatly, and efficiency of the motor is improved.

The invention discloses an LCC-MMC (line commutated converter-modular multilevel converter) staggered and mixed bipolar direct current power transmission system. The system comprises a sending end convertor station and a receiving end convertor station, wherein an anode of the sending end convertor station comprises an LCC 1, a cathode of the sending end convertor station comprises an MMC 4; an anode of the receiving end convertor station comprises an MMC 3, and a cathode of the receiving end convertor station comprises an LCC 5; the anode of the sending end convertor station is connected with the anode of the receiving end convertor station through a direct current transmission line, and the cathode of the sending end convertor station is connected with the cathode of the receiving end convertor station through a direct current power transmission line. The floor space of the LCC-MMC staggered and mixed bipolar direct current power transmission system is smaller than that of a conventional direct current power transmission system based on a thyristor and that of a flexible direct current power transmission system completely based on the MMC, and the LCC-MMC staggered and mixed bipolar direct current power transmission system can be connected with a weak alternating current system and realizes decoupling control of active power and reactive power; an unilateral diode of a direct current line can prevent three-phase short circuit current from passing by the MMC when bipolar direct current short circuit fault occurs.

The invention introduces a design method and control method of a robust pitch controller above the rated wind speed of a wind power generator. The pitch controller design method first establishes the blade load model, performs vector transformation to achieve decoupling, and linearizes the decoupling model in the vertex set of the scheduling parameter convex set; secondly, converts the model into an LPV system, and uses H The ∞ theory standardizes the model as a standardized augmented control object containing performance indicators, uses the linear matrix inequality method to design the controllers on the vertex set of the convex set of scheduling parameters, and uses the gain scheduling principle to obtain the global pitch controller, and finally uses the vector The inverse of the transform yields the actual control signal.

The invention provides a coordination control method of an integrated gasification combined cycle power station and particularly provides an energy-balance based coordination control method, aiming at the characteristic that time constant difference among all equipment of a controlled object of the integrated gasification combined cycle power station is large. According to the method, field signals are acquired, a gasification furnace and a gas turbine are regulated in the way of calculating the gasification furnace heat signal and the gas turbine heat signal, so the decoupling control on a power island and a gasification island is realized, gas turbine power and gas pressure before valve regulation are synchronously controlled, so that the heat signal tracks the energy signal, and thus the coordination control of the integrated gasification combined cycle power station is realized. Through control system architecture design and parameter regulation, in use, the method can effectively coordinate the operation of all the equipment of the gasification furnace and the power island of the power station, the load of the power station can be quickly and automatically regulated, and the operation stability of the power station can be ensured; and the method is a coordination control of a gas-steam combined cycle power station and has good stability and varying load performance.

The invention discloses a charging device for a tramcar super-capacitor, comprising two independently operating rectification voltage regulation circuits; the rectification voltage regulation circuits comprise LCL filter capacitor modules, PWM rectifier bridge modules and DC / DC convertor modules which are sequentially connected; the DC / DC convertor modules are connected to an isolation switch cabinet through clamping diodes; the invention also discloses a charging method for the tramcar super-capacitor, comprising: a constant current charging stage and a constant voltage charging stage, after the tramcar super-capacitor is charged to the set value, switching from the constant current charging stage to the constant voltage charging stage, taking the integral output value of a current PI regulator before switching as the integral initial value of a voltage PI regulator after switching, and realizing seamless switching of the two stages.

The invention discloses a two-degree-of-freedom dual-winding hybrid magnetic bearing switched reluctance motor and a control method thereof, and belongs to the field of a magnetic suspension motor and control thereof. The motor comprises a 12 / 8-pole switched reluctance motor and a 12-pole magnetic bearing, wherein a suspension winding and a bias winding are wound around each of four stators of the magnetic bearing, all bias windings are connected and then are connected in series with an A-phase winding of the reluctance motor to form an A-phase composite excitation winding, a constant conduction excitation mode is employed, bias magnetic flux is generated in the magnetic bearing, and meanwhile, a torque is generated in the reluctance motor; a B phase and a C phase employ modes of excitation in turns, and the A phase employs asymmetric excitation in a positive and negative half period to generate an effective torque; and the A phase provides the bias magnetic flux by control and also generates an average torque equal to those of the other two phases, and the average output torques output from the three phases are symmetric. By the motor and the control method, the magnetic bearing and the reluctance motor are isolated, no coupling is generated between magnetic paths, the torques and the suspension forces are decoupled, and a power system is low in cost and is simple to control.

The invention discloses a system and a method for controlling a doubly-fed wind power generation grid-side converter. The system comprises a model predictive control module and a space vector modulation module. The model predictive control module controls a voltage transfer function according to dq-axis current and the dq axis of the grid-side converter, acquires a first-order difference equation of a PWM-VSR (pulse width modulation voltage source rectifier) after discretization to serve as a predictive control model and calculates control voltage of the grid-side converter in a real-time online manner by feedback correction and rolling optimization. The space vector modulation module generates a switching signal for operation of the grid-side converter according to the control voltage and controls the grid-side converter in grid-connected operation. By the aid of the system and the method, the influence of lagging of the control voltage caused by sampling delay of voltage and current of the grid-side converter can be eliminated, grid-side dq-axis current is completely decoupled, the negative influence of grid-side inductance parameters on stability and dynamic response of the system can be overcome, three-phase input current effectively tracks input power grid voltage phase, and the grid-side converter is ensured to be operated in a high power factor state.

The present invention discloses a multi-control surface unmanned aerial vehicle direct lift force control method. The method is characterized in that an error of an expected lift force increment and an actual lift force increment, and an error of an expected pitching moment increment and an actual pitching moment increment are calculated according to an expected longitudinal trajectory command, a pitching angle command, and the measured flight state information, such as the height, the speed, the acceleration, the pitching angle, the pitching angle acceleration, etc., and a dynamic control distribution method is adopted to carry out the control distribution calculation on the lift force increment error and the pitching moment increment error real-timely, so that the deflection angle of each control surface is obtained. According to the present invention, by the closed loop force and the moment control distribution, the direct lift force control of a multi-control surface unmanned aerial vehicle is realized, and a better posture and trajectory decoupling control effect is obtained. The method of the present invention can be applied to the direct lift force flight control of the unmanned aerial vehicle possessing the redundant control surfaces, thereby realizing the decoupling control of the pitching angle posture and the height trajectory of the unmanned aerial vehicle.

The invention discloses a four-rotor aircraft robust tracking control method based on iterative learning, and the method comprises the steps: carrying out the analysis of a four-rotor aircraft dynamicdifferential equation containing time-varying uncertainty, and building a position and attitude tracking error subsystem; obtaining a state space model of the attitude tracking error subsystem, defining coupling uncertainty of the position tracking error subsystem, and establishing a state space model of the position tracking error subsystem; considering time-varying and coupling uncertainty characteristics, and establishing a cost function considering a coupling uncertainty item for a nominal system of a position tracking error subsystem and an attitude tracking error subsystem; based on thecost function, performing solving to obtain an optimal control rate; based on an adaptive dynamic programming method, designing an improved neural network weight updating rule, obtaining a robust tracking controller through approximate solution, and achieving approximate optimal tracking control based on iterative learning. The robust tracking control problem of the four-rotor aircraft system under time-varying and coupling uncertainty is solved.

The invention discloses a method for controlling a power-assisted motor of an electrical power-assisted steering system under the intervention of active steering, and belongs to the field of the control of power-assisted motors of electrical power-assisted steering systems having the active steering function. The method comprises the following steps of: calculating a required feedforward power-assisted amending control current signal deta Ia by utilizing a feedforward power-assisted amending control module (7) according to an additional intersection angle theta ac and a feedforward transfer function G deta I(s), performing linear superposition of the amending control current signal deta Ia and the conventional power-assisted control current signal Ia to obtain a power-assisted motor totalcontrol current signal for controlling the power-assisted motor to exert power-assisted moment Ta, wherein the power-assisted moment Ta and steering wheel torque Td exerted by drivers overcome steering resisting moment TR commonly, and driving a wheel to complete steering by a steering transmission mechanism (10). By the method, the problem that the control moment of a steering wheel is changed suddenly with the intervention of the active steering additional intersection angle under high-speed running is solved, the steering road feel of the steering system under the intervention of the active steering is improved, and the requirement for safe driving during the high-speed running is met.

The invention relates to the field of power converters of drive motors, in particular to an optimization and modulation method of duty ratios of a five-bridge-arm voltage source inverter. The method includes the steps that three-phase stator currents of two motors are converted into dq axial current components under a two-phase rotating coordinate system through abc coordinates and dq coordinates respectively; PI controllers are adopted in rotating speed loops and current loops; required duty ratio reference values of drive signals of the two motors are generated by using voltage reference values of direct current bus voltages under a two-phase static coordinate system and through space vector pulse width modulation; the duty ratios are optimized and modulated in each sampling period. By the adoption of the optimization and modulation method, it is guaranteed that a common bridge arm can control the two motors at the same time in the modulation period, the control decoupling problem of the two motors is solved, the time of the two motors for being controlled by zero voltage vectors is effectively shortened, the utilization rate of the direct current bus voltages is improved, and the speed regulating range of a system is expanded.

The invention relates to a fault-tolerant direct torque control method of a series motor driving system having an input lack of a phase. The fault-tolerant direct torque control method is particularly applied to a six-phase permanent-magnet synchronous motor of which power is supplied by a single inverter and which is connected in series with a three-phase permanent-magnet synchronous motor driving system, and aims to achieve decoupling control on instantaneous electromagnetic torques of two motors by using remaining five-phase inversion bridge when an input end of the dual-motor series driving system is lack of a phase, so that the reliability of the series driving system is improved.

The invention discloses a sliding mode repetitive controller suitable for a four-rotor aircraft. The controller is characterized in that firstly, improving a common exponential reaching law, designinga novel improved reaching law by utilizing a high-order function and a logarithmic function, discretizing a kinetic model of a four-rotor aircraft to adapt to the design of a digital controller, decoupling position coordinates and an attitude angle through the virtual control quantity, and designing discrete sliding mode repetitive controllers for a position subsystem and an attitude subsystem respectively to overcome periodic interference and realize tracking control of the aircraft on a given trajectory. The method is advantaged in that a control algorithm can be conveniently realized on adigital chip, so the aircraft control system has good repetitive trajectory operation performance while having robustness, a problem of steady-state buffeting of the reaching law is solved, and decoupling control of the four-rotor aircraft is realized.