2181results about How to "Fast dynamic response" patented technology

An adaptive switch mode LED driver provides an intelligent approach to driving multiple strings of LEDs. The LED driver determines an optimal current level for each LED channel from a limited set of allowed currents. The LDO driver then determines a PWM duty cycle for driving the LEDs in each LED channel to provide precise brightness control over the LED channels. Beneficially, the LED driver minimizes the power dissipation in the LDO circuits driving each LED string, while also ensuring that the currents in each LED string are maintained within a limited range. A sample and hold LDO allows PWM control over extreme duty cycles with very fast dynamic response. Furthermore, fault protection circuitry ensures fault-free startup and operation of the LED driver.

The invention relates to a current predictive control method of a permanent magnet synchronous motor, which belongs to the electric control field. The dynamic response speed and the control accuracy for the stator current control of the permanent magnet synchronous motor are improved through stator current prediction and deadbeat control, and the system delaying is compensated, so that the noise and the torque ripple of the motor in operation are reduced. The method comprises the steps as follows: obtaining a three phase stator current signal, and the electrical angle and the electrical angular speed of the motor rotor through the technologies of sensor sampling and a photoelectric coded disc or position sensorless detection; carrying out Clarke transformation and Park transformation on the stator current signal to obtain the stator current in a synchronous revolution dq coordinate system; substituting the obtained stator current signal in the dq coordinate system into a control equation of a current predictive controller of the permanent magnet synchronous motor, carrying out deadbeat control according to the given value of the obtained stator current in the dq coordinate system in an outer ring controller to obtain a stator voltage vector in the dq coordinate system; carrying out Park inverse transformation on the obtained stator voltage vector in the dq coordinate system, to obtain a pulse-width modulation (PWM) control signal of an inverter by a space vector pulse width modulation (SVPWM) method, controlling the stator current through the inverter, and then implementing the current predictive control over the permanent magnet synchronous motor.

The present invention discloses a power supply device with low standby loss. The power supply device comprises a main power converter and an auxiliary power converter. The main power converter comprises a bulk capacitor. The main power converter connects parallelly with the auxiliary power converter. When the power supply device is in a standby mode, the main converter is turned off and the auxiliary converter provides the output to the outputting load and the bulk capacitor. Moreover, when the power supply device is in a normal mode, the main converter and the auxiliary converter together provide the output to an outputting load. Under a normal mode, the main converter provides most of the power and the auxiliary converter operates in a power-limited finite value such that the topology of the power supply device achieves a low standby loss.

A converter unit to improve the response dynamics and overall recovered power in a photovoltaic array configuration. Each photovoltaic panel in the photovoltaic array may be coupled to a respective converter unit, which may include a controller to sense an output voltage and output current produced by the solar panel, and control operation of a power converter to output modified voltage and current corresponding to the solar panel onto a bus coupling the converter units. The controller may operate as an analog or (digital) firmware control system to regulate the input voltage of each power converter unit under indirect guidance of a Maximum Power Point Tracking (MPPT) controller to optimize and regulate the resultant power, and achieve very fast dynamic response to environmental transients. Input voltage and output voltage management may be achieved by way of a fast inner control loop and a corresponding MPPT control system configured as an outer guidance loop providing a reference signal to the inner control loop.

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 parallel current sharing circuit of a charging module of an electric automobile charger, comprising a charger monitoring unit and at least one charging module which are connected in parallel, wherein the charging modules are linked in parallel; the charger monitoring unit is connected with the charging modules through communication signal lines; and the charging modules are connected through average current signal lines, and connected with a grid alternating current end and a power battery direct current end of the electric automobile respectively. By using the current sharing circuit disclosed by the invention, the sampling feedback coefficient of the output voltage of the module is adjusted according to the differential value between a module charging current sampling signal and average current signals of all the parallel modules, thus the charging voltage and the charging current of the module are further adjusted to reach the purpose of load-sharing current in parallel of every charging module. The parallel current sharing circuit has relatively high current sharing precision and current sharing dynamic responding speed, is beneficial to improving the reliability and the maintainable performance of the charger and better satisfies the charging requirement of the power battery of the electric automobile.

The invention relates to the technical field of switching power supply and discloses a direct current switching power supply parallel system current sharing control method and a control device. The control device comprises a plurality of switching power supply current sharing modules which are connected in parallel and an extreme current selective circuit, wherein load output terminals of a plurality of switching power supply current sharing modules which are connected in parallel are connected with loads, and the extreme current selective terminals of a plurality of switching power supply current sharing modules which are connected in parallel are connected with the extreme current selective circuit. By applying the direct current switching power supply parallel system current sharing control method and control device disclosed by the invention, a direct current switching power supply parallel system can operate normally under the condition that a basic element is in fault, thus the direct current switching power supply parallel system current sharing control method and control device are applicable to a power supply parallel system with redundant structure, and reliability and safety of the a power supply system and loads are improved; and power supply equipment cost is reduced, the aim of current sharing of the parallel system is realized, regulating frequency of a power supply module of the power supply system is reduced, low-frequency oscillation produced by output current is effectively avoided and dynamic response of the system is further improved while no intelligent controller (CPU) or complex programming technology is adopted.

An antiskid control method for train includes such steps as setting up optimal control function according to train speed and the difference between actual speed and calculated speed, evaluating the utilization of adhesion to obtain comprehensive index value, and controlling antiskid valves to increase, decrease, or hold the pressure. Its apparatus is composed of antiskid controller. 4 antiskid valves and 4 speed sensors.

The invention discloses a device and a method for high-accuracy measurement of expansion coefficients of a metal wire. The method uses a PZT oscillating mirror system to perform frequency modulation on incident light at different times, can not only modulate parameter information to be measured to a phase difference, but also modulate the parameter information to be measured to in a frequency difference for the convenience of later signal treatments; and the device consists of an interference system, a high-speed PZT oscillating mirror system, a heating system and a signal processing system. Comparing the method with other measuring methods, a multi-beam laser heterodyne measuring method for measuring the expansion coefficients of the metal wire has the advantages of high space and time resolutions, high measurement accuracy, high linearity, quick dynamic response, large measuring range and the like, and simultaneously the method has the advantages of simple structure for an experimental apparatus, low power consumption, convenient operation, high repeatability, small experimental result error, high accuracy and the like. Because experimental phenomena are obvious and experimental data is reliable, the method and the device can be widely applied in the fields of engineering designs and the like, and have very high practical values in the field of laser ultra-precision measurements.

The invention relates to dynamic loading methods based on a servo motor, belonging to the field of motors and solving the problem that the properties of a direct-current motor can not satisfy the requirements of an electric loading system. The first method comprises the following steps of: transmitting a driving torque instruction value and an initial braking torque instruction value by utilizing a system controller according to the given loading spectrum to drive a measured motor to rotate; meanwhile, driving a loading motor to generate a braking torque for loading the measured motor; and then, feeding back the actual output torque value applied to the measured motor by the loading motor through adopting a torque/rotary speed sensor, and regulating the braking torque instruction value by utilizing the system controller according to a deviation so that the actual output torque value applied to the measured motor by the loading motor rapidly tracks the initial braking torque instruction value. The second method of the invention comprises the following steps of: calibrating the input and output torque relation curve of the loading motor by using the torque/rotary speed sensor, and then transmitting the driving torque instruction value and the braking torque instruction by using the system controller according to the given loading spectrum and the relation curve to load the measured motor.

A control system is described for a base supporting a telescoping articulated boom assembly indicated generally at 15, comprising long telescopic boom 17 and telescopic stick 19. Mounted to the remote end 21 of the stick 19 is an end effector in the form of a head 23 that supports a 6 axis robot arm 25 that moves a further end effector 27 to manipulate the items. The robot arm 25 has a robot base 31, and mounted above the robot base 31 is a first target in the form of a 6 degree of freedom (6 DOF) high data rate position sensor 33, that provides 6 DOF position coordinates, relative to a fixed ground reference 35, to a control system. Mounted on the end of the robot arm 25 immediately above the end effector 27 is a second target in the form of a 6 degree of freedom (6 DOF) high data rate position sensor 37, that provides 6 DOF position coordinates, relative to the fixed ground reference 35, to the control system. The fixed ground reference 35 tracks the sensor 33 and feeds data to the control system to move the head with slow dynamic response within range of work for the robot arm, and tracks the sensor 37 to control movement of the robotic arm 25 and end effector 27 with fast dynamic response.

The invention relates to a mono-dual frequency electromagnetic flowmeter excitation control system based on linear power supply, comprising a constant current source circuit, a current bypass circuit,an exciting coil driving circuit, an excitation time sequence generating circuit and a galvo circuit. A high voltage power supply is adopted for supplying power, the constant current source is constructed by linear power supply to supplying electricity for the exciting coil driving circuit, the current bypass circuit is jointed in parallel with the input/output end of the linear power supply to solve the problem of energy dissipation, the exciting coil driving circuit is composed of an H bridge and a control circuit thereof, the galvo circuit is bridge-jointed between the lower end of the H bridge and a reference ground, and a digital signal processor (DSP) is used for controlling multiple switches and an electrical level matching device to generate time sequence and control the action ofthe exciting coil driving circuit. The excitation control system can obviously improve excitation frequency range and excitation frequency preciseness, is suitable for single frequency high frequencysquare wave excitation or dual frequency square wave excitation, and can simultaneously provide more exact current detection to correct the flow signal processing result.

The invention provides a finite-time full-order sliding mode control method of a quadrotor unmanned aircraft. For the quadrotor unmanned aircraft whose model parameters are coupled in a non-linear manner, a full-order sliding mode control method is utilized and a one-order filter is adopted to design the finite-time full-order sliding mode control method of the quadrotor unmanned aircraft. The design of full-order sliding mode surfaces ensures the rapid and stable convergence of the system. In a practical control system, two full-order sliding mode surfaces including the design position and attitude angle are degisned as inner and outer control rings to realize rapid tracking of the aircraft, and the filter is added to improve the buffeting problem. The invention provides the finite-time full-order sliding mode control method of the quadrotor unmanned aircraft, based on the condition that the system model parameters are coupled in a non-linear manner, rapid convergence to a balance point in finite time of the system is ensured, the response speed of the system is increased, the buffeting of sliding mode control input is improved, and the rapid and stable tracking performance of the system is effectively realized.

An energy-saving control system for hydraulic elevator features use of a hydraulic pressure changer composed of variable or quantitative pump and motor. Said pressure changer can get energy from constant-pressure network and provide it to load without pressure loss, or reverse the energy from load. Its avdantages are high dynamic response speed and pressure amplifying effect.

The invention discloses a permanent-magnet synchronous motor torque control system and method based on sliding-mode observer and auto-disturbance rejection control, so that the torque of the permanent-magnet synchronous motor is controlled rapidly and precisely. A minimal-order extended flux-linkage sliding-mode observer is designed; an auto-disturbance rejection current controller is designed; difference processing is carried out on an electromagnetic torque outputted by an observer and a given torque signal outputted by an upper computer and the difference is inputted into a PI controller; a q-axis current signal outputted by the PI controller and dq-axis flux-linkage component outputted by the observer are inputted into the auto-disturbance rejection current controller to form a torque closed loop. According to the permanent-magnet synchronous motor torque control system and method, the dynamic response of the output torque of the motor is accelerated and no overshoot phenomenon is avoided. Moreover, on the basis of combination of the sliding-mode observer and the auto-disturbance rejection controller, the reliability and robustness of the torque control of the permanent-magnet synchronous motor are enhanced. The permanent-magnet synchronous motor torque control system and method are applied to occasions with the permanent-magnet synchronous motor as a driving system.

A portable IGBT (Insulated Gate Bipolar Transistor) of high reliability, compact size, and low cost includes a main circuit to which a control circuit and an auxiliary power supply circuit are connected. The main circuit includes, in sequence, an input rectifier filter circuit, an inverter circuit, a high-frequency primary transformer, and a secondary output rectifier circuit. The control circuit includes a PWM regulation circuit, an IGBT driving circuit, a current feedback circuit, and a current setup circuit. The inverter circuit includes a full-bridge hard switching structure, which has IGBTs constituting bridge arms that are sequentially conducted, so that their alternating conduction converts direct current into high frequency square wave alternating current, which flows through the high-frequency primary transformer and is then subjected to rectification to supply an output of low voltage direct current. Each IGBT is connected in parallel to resistor and capacitor, which constitute a peak voltage absorption circuitry.

Aiming at a problem that an ip-iq algorithm cannot precisely acquire fundamental wave positive sequence active currents under the conditions of non-ideal power network voltages, the invention provides a method for detecting a harmonic wave and a reactive current based on spatial transformation of voltage vectors. The method comprises the steps of performing coordinate transformation on currents and voltages on an ip-iq algorithm channel to acquire phase information of three-phase fundamental wave positive sequence voltages; defining a p-q coordinate system; defining correct positive sequence active components and positive sequence reactive components by using the projection of a current vector on a voltage vector and a normal line thereof under the coordinate system; then accurately solving fundamental wave positive sequence active components, fundamental wave positive sequence reactive components, fundamental wave negative sequence active components and fundamental wave negative sequence reactive components in a load current by taking the correct positive sequence active components and the positive sequence reactive components as reference volumes and using an improved ip-iq algorithm; and popularizing the detection of the four fundamental wave current magnitudes into the detection of any sub-harmonic current magnitude to form a current detection system under the conditions of non-ideal voltages so as to provide reasonable reference instruction currents for various compensation requirements.

A two-rotation two-motion four-freedom-degree parallel excitation platform comprises a movable platform, a fixed platform, four driving branches of the same structure and a middle restraint branch, wherein the four driving branches and the middle restraint branch are used for connecting the two platforms. The four driving branches are respectively of a PSS structure. In each driving branch, a linear module (in an electric driven mode) is fixed to the fixed platform and connected with a sliding block through a sliding pair, one end of a connecting rod is connected with the sliding block through a first ball pair, and the other end of the connecting rod is connected with the movable platform through a second ball pair. The middle restraint branch is of a PPU structure. A guide rail in the middle restraint branch is fixed to the fixed platform, one end of a lower connecting rod is connected with the guide rail through a first sliding pair, the other end of the lower connecting rod is connected with one end of an upper connecting rod through a second sliding pair, and the other end of the upper connecting rod is connected with the movable platform through a universal hinge. The two-rotation two-motion four-freedom-degree parallel excitation platform can achieve the space two-dimensional independent rotational freedom degree and the two-dimensional independent movement freedom degree and has the advantages of being simple and compact in structure, rapid in dynamic response, easy to install and maintain and the like.

Methods, circuits, and apparatuses are disclosed that provide a buffer amplifier with lower output noise by narrow banding the amplifier. To reinvigorate the speed of the narrow-banded amplifier, a boost-on signal is initiated. The boost-on signal dynamically and rapidly injects a substantial current into the amplifier's bias current network to speed up its slew rate, when the amplifier's inputs get unbalanced when being subjected to a large transient differential input signal. Subsequently, after the amplifier regulate itself and as the amplifier's inputs approach substantial balance, a boost-off signal dynamically injects a slow and decaying current (that converges to the level of static steady-state bias current) into amplifier's bias circuitry, instead of turning off the boost current rapidly, which improves the amplifier's settling time.

The invention discloses an industrial laser guidance automatic guided vehicle (AGV) double-closed-loop control system and a control method thereof. The system consists of a detection module and a control module and is characterized in that: the detection module consists of an encoder serving as a motor position sensor and a laser scanner serving as an AGV position sensor; the control module consists of a servo driver and an industrial personal computer and is a double-position closed loop control module consisting of an inner position ring and an outer position ring; the inner position ring is a motor intersection angle position ring; the outer position ring is used for reading an AGV position signal by using the laser scanner; the path tracking error of the current position of an AGV is calculated by the AGV position signal fed back from the outer position ring; and the path tracking error is used as the input quantity of the control system. By the system and the method, the independent running function of the industrial laser guidance AGV can be well realized, and the rapidity and the stability of the path tracking of the AGV can be ensured.

The invention discloses a three-phase LCL type grid-connected inverter control system based on pole assignment, and the grid-connected inverter control system restrains the influence of power grid impedance on a three-phase LCL type grid-connected inverter, can effectively solve the problem that a grid-connected system is instable due to the power grid impedance and can be used for current control over the grid-connected inverter. A grid-connected control method not only can achieve system stability and high-quality grid connection under the condition of a weak grid, but also avoids the complex design of a current controller, coordinate rotation transformation and decoupling control. Meanwhile, the grid-connected control method can automatically adjust grid-connected current reference values to achieve independent control over reactive power according to given signals of externally-set reactive power. Therefore, the grid-connected control method is more suitable for controlling the photovoltaic power station grid-connected inverter which is connected into the weak grid through a long-distance power transmission line.

The invention discloses a direct torque control method for a six-phase synchronous motor with zero-sequence current self-correction. The direct torque control method for the six-phase synchronous motor with the zero-sequence current self-correction comprises firstly, performing voltage vector reconstruction based on an idea that a zero-sequence current is equal to zero and accordingly proposing an idea DTC (Direct Torque Control); secondly, performing discrete compensation on the actual voltage vector acting time based on the dead-time compensation principle; finally, continuously compensating the voltage vector acting time through a PI adjuster and achieving a purpose that the zero-sequence current is equal to zero. The direct torque control method for the six-phase synchronous motor with the zero-sequence current self-correction solves the problem of eliminating low-order harmonic currents in a six-phase symmetrical winding permanent magnet motor DTC system of a torque and magnetic flux linkage double-hysteresis-loop structure.