115results about How to "Extended speed range" patented technology

A magnetically-levitated blood pump with an optimization method that enables miniaturization and supercritical operation. The blood pump includes an optimized annular blood gap that increases blood flow and also provides a reduction in bearing stiffness among the permanent magnet bearings. Sensors are configured and placed optimally to provide space savings for the motor and magnet sections of the blood pump. Rotor mass is increased by providing permanent magnet placement deep within the rotor enabled by a draw rod configuration.

A device to regulate current produced by a permanent magnet machine responsive to a plurality of phase current signals. The motor produces torque for application on a shaft. A processing and drive circuit responsive to a direct current command signal and a quadrature current command signal produces phase current signals for input to the motor. A command circuit responsive to the phase current signals, an angular position of said shaft, and a voltage input command signal to produce a direct current error signal and a quadrature current error signal. A control circuit responsive to the direct and quadrature current error signals produces the direct voltage signal command and the quadrature voltage signal command. The control circuit has a direct and quadrature proportional gain, integrator and clamp circuits. An algorithm produces limited or clamped voltage modulation index signals to obtain maximum efficiency and maximum torque per ampere in the speed range. The algorithm ensures that the current regulator does not run out of voltage by limiting the voltage vector to the achievable voltage vector range that provides maximum torque per ampere and maximum efficiency.

The invention relates to a high-speed dynamic simulation test method used for an electric mainshaft bearing. The electric mainshaft bearing comprises a frame, a main body pedestal, an axial loading cylinder, a test head assembly, a main body gland, a radial loading cylinder, a shaft coupling, a protecting hood, an electric mainshaft, a lubricating oil pipe, an axial loading oil pipe, a vibration sensor, a radial loading oil pipe and a temperature sensor and also a final assembly of all the parts. A hydraulic loading system is started to provide pressure oil to the axial loading cylinder and the radial loading cylinder, the electric mainshaft drives a test mainshaft to rotate, the radial loading cylinder exerts radial force on a first test accompanying bearing and a second test accompanying bearing through a radial loading sleeve, and the radial loading cylinder exerts axial force on a first test bearing and a second test bearing through an axial loading sleeve. The entire test is controlled by a computer to display parameters of the rotating speed, the axial load and the radial load, the oil pressure, the cooling water temperature, the bearing temperature, the bearing vibration, the power current of the electric mainshaft and the test time, and the parameters are saved in a computer database and analyzed.

The permanent magnet brushless motor permits dynamic change of output characteristics by varying the positional relationships of rotor components, with respect to each other and with respect to the stator, to progressively effect field weakening with increasing speeds. The force required to impart the limited range of motion involved is transmitted to the rotor component by way of bearings and/or an actuation motor, and a helical guide path is used to great advantage for constraining such movement. The wide, dynamically adjustable motor output range of the motor effectively provides the equivalent of an efficient, continuously variable transmission. High torque at low speeds, and efficient, constant power output over a wide high speed range, uniquely adapt the motor for use as the prime mover for electric/hybrid vehicles.

A sensor module (1) for measuring the distance to a target and/or the velocity of the target (50), the sensor module (1) comprising at least one laser source (100), at least one detector (200) being adapted to detect modulated laser light and at least one control element the control element (400) being adapted to vary the focus point of the laser light and/or the intensity of the laser light and/or the direction of the laser light. The control of the laser light emitted by the laser source (100) either by active optical devices as variable focus lenses or controllable attenuators or passive optical elements in combination with arrays of laser sources (100) and detectors (200) enable flexible and robust sensor modules.

A closed-loop permanent magnet motor control method and system optimally partitions torque and flux-weakening currents to produce a desired torque without exceeding the capability of the DC source. A maximum limit for allowable torque current and a minimum threshold for the maximum torque current are determined, and the flux current is varied based at least in part on whether the maximum torque current limit is above or below the minimum threshold while operating in a flux-weakening region to compensate for the variability of the DC source voltage.

A motor comprising a motor-wiring bus bar including a plurality of annular ring conductors connecting lead wires of the motor including a stator in which a plurality of stator cores having the lead wires is arranged in a circle or connecting the lead wires and a power line together and a plurality of terminals attached to the ring conductors. The ring conductors are different in diameter and arranged concentrically on a same plane.

The invention relates to a high-temperature high-speed test method for a sealed bearing, which comprises the following steps of: firstly designing a testing device, installing two sets of testing accompanying bearings on a testing main shaft, and pretightening through a set of spring and a pressure ring; installing the two sets of testing bearings at the left end and the right end of the testing main shaft, connecting an electric main shaft through a shaft coupling and additionally covering a shield; starting cooling circulating water, adding cooling water into a loading sleeve, starting a hydraulic station, an electric main shaft variable-frequency driving system and a computer control system, applying 20-30 percent of the maximum axial test load and 20-30 percent of the maximum radial test load to the testing bearings, starting the electric main shaft to reach 15-20 percent of the highest rotational speed and running for 15-25 minutes after the heating temperature reaches a set value, and then sequentially adding axial loads and radial loads and increasing the rotational speed of the electric main shaft so as to reach the highest rotational speed when the power consumption current of the electric main shaft tends to be steady; and carrying out computer data processing for the data and images in different time periods of the whole testing process and working out a test conclusion.

A method and apparatus are provided for controlling the operation of a pump, such as a centrifugal pump, featuring steps of either adjusting the operation of the pump, or issues a warning to a user of the pump of an undesirable operating condition, or both, based on a comparison of an actual torque value and a corrected torque value either alone or in combination with a further step of compensating the corrected torque value based on a mechanical power offset correction. The corrected torque value may include a Best Efficiency Point (BEP) torque value and may also be compensated for based on at least the current operating speed of the pump. The pump has a controller for performing the steps of the method. The controller can compensate the corrected torque value based on the square of the speed change of the pump. The comparison may include a ratio of the actual torque value to the corrected torque value, and the ratio of the actual torque value to the corrected torque value may also be compared to ratios corresponding to either a dry run condition, a minimum flow condition, a runout condition, or some combination thereof.

There is provided a radar device. A transmitting unit transmits first and second transmission signals generated based on first and second parameters for computing relative velocities in first and second detection velocity ranges, respectively. The second detection velocity range is narrower than the first detection velocity range. A receiving unit receives the reflected waves of the first and second transmission signals from a target as first and second reception signals, respectively. A velocity measuring unit computes first and second relative velocities in the first and second detection velocity ranges based on the first and second reception signals, respectively and obtains the velocity measurement result of the relative velocity of the target based on the combination of the first and second relative velocities.

The invention discloses a website security detection method and device. The website security detection method comprises the steps that a website is obtained; website programs used by the website are identified based on website fingerprint information of the website, and loophole detection is conducted on the website according to the website programs; lastly, a detection result is returned. By means of the website security detection method and device, the cost of the loophole detection on the website can be reduced obviously, the loophole detection speed can be increased, and the rate of missing report can be decreased.

The invention discloses a permanent magnet motor rotor with an excitation circuit variable reluctance and leakage flux path function, which belongs to the technical field of the motor and solves the problem that in the weak magnet speed regulation technology of the traditional synchronous permanent magnet motor, the permanent magnet motor is difficult in weak magnet speed regulation because excitation can not be regulated. The permanent magnet motor rotor with the excitation circuit variable reluctance and leakage flux path function comprises a rotor iron core, 2n main permanent magnets and 2n weak magnet units, wherein n is a positive integer; 2n trough slots are arranged along the axial direction of the rotor iron core and are evenly distributed along the peripheral direction of the rotor iron core; one main permanent magnet with a shape matched with the shape of each through slot is respectively embedded in each trough; a weak magnet unit is arranged between every two adjacent main permanent magnets along the peripheral direction of the rotor iron core; magnetic isolation grooves are arranged among two ends of the main permanent magnets along the peripheral direction and the adjacent weak magnet units; the main permanent magnet adopts radial magnetization; and the magnetization directions of the adjacent main permanent magnets are opposite. The invention is suitable for the permanent magnet motor.

Actuator control system and method comprising an electric motor driving a hydraulic pump in fluid delivery communication with a source of hydraulic fluid; a variable speed controller operatively coupled to the motor for driving the pump at variable speeds; an external hydraulic actuator in fluid delivery communication with the pump for receiving pressurized fluid flow from the pump; and a feedback loop operatively coupled from the motor to the controller for providing feedback signals correlative to a pressure of the pressurized fluid flow through the driven pump for driving the external hydraulic actuator in response to the feedback signals for providing electronic velocity and force control of actuation of the external hydraulic actuator. The actuator control system and method can operate on one or many high-pressure hydraulic linear and/or rotary actuators on different pieces of hydraulically driven equipment and with different velocity requirements actuating in different directions.

An upper bridge of the power converter drives a half of phase windings. A lower bridge of the power converter drives the other half of the phase windings. For example, an upper neutral point of a star-connected upper phase windings is connected to a lower neutral point of a star-connected lower phase windings via a connection switch. A current-absorbing leg absorbs a current from the upper neutral point. A current-supplying leg supplies a current to the lower neutral point. Preferably, the power converter has an asymmetric bridge mode, a dual Miller mode and an accelerated bridge mode by means of switching the connection switch, the current-absorbing leg and the current-supplying leg.

The invention discloses a vector type permanent magnetic brushless motor control method. When a motor starts, by use of a constant-torque zone current closed-loop control method, a permanent magnetic brushless motor is controlled, when a PWM duty ratio output by an electric current loop proportional integral controller reaches a set threshold, by use of a constant-power weak-magnetic zone torque closed-loop control method, the permanent magnetic brushless motor is controlled; and in the constant-power weak-magnetic zone torque closed-loop control method, when a weak-magnetic control advanced conduction overlap angle delta theta FW output by a torque ring proportional integral controller is lower than a set threshold, by use of a constant-torque zone current closed-loop control method, the permanent magnetic brushless motor is controlled.

The invention belongs to the technical field of ultra-high-speed impact loading test, in particular to a three-stage light gas gun. The technical scheme of the three-stage light gas cannon driven by hydrogen-oxygen mixed detonation is: the ratio of the inner diameter of the first-stage pump tube to the inner diameter of the second-stage pump tube is 2 to 4, and the ratio of the inner diameter of the second-stage pump tube to the inner diameter of the launch tube Between 3 and 5; the aspect ratio of the primary pump tube is 3 to 5, the aspect ratio of the secondary pump tube is 4 to 7, and the aspect ratio of the launching tube is 1 to 2; the cone angle of the primary high pressure cone section The cone angle of the secondary high-pressure cone section is 5°-25°; the combustion chamber is filled with a mixture of hydrogen, oxygen and nitrogen, and the primary pump tube and the secondary pump tube are respectively filled with hydrogen gas to launch The tube is vacuumed. The invention adopts hydrogen-oxygen mixed gas as a driving source, has stronger loading capacity, low pollution, and stably launches a projectile with a mass of 1g at a speed exceeding 10km/s.

A brushless direct current motor is energized by a power stage. Switches of the power stage are selectively switched by an electronic control device. In order to determine the correct commutation pattern, without using rotor position indicators such as Hall effect devices, the control device is arranged to sample the power fed to the motor. The samples, each responsive to a test signal or normal energization pulses received by the motor, in a ordered sequence define an analogue function whose parameters can be determined by mathematical analysis. The analysis applied to the samples derives the necessary commutation information and the energization signals in a rapid manner by employing a vector or complex number addition based on functions dependent on variable inductance in the operation of the motor.