682results about "Stopping arrangements" patented technology

A motorized surgical instrument is disclosed. The surgical instrument includes a control circuit configured to control the movement of an end effector. If the end effector moves outside a predetermined acceptable range, the control circuit may create a dynamic brake to resist the undesired movement of the end effector. The control circuit may apply pulse width modulated (PWM) current to resist the undesired movement of the end effector outside a predetermined acceptable range.

A disk drive is disclosed comprising a disk, a head actuated over the disk, and a spindle motor for rotating the disk, the spindle motor comprising a plurality of windings. Disk control circuitry executes a spin-down operation of the spindle motor by estimating an angular position of the spindle motor by applying a voltage to at least one of the windings and evaluating a rise time of current flowing through the winding. The windings are commutated in response to the estimated angular position, and a driving current is applied to the windings to brake the spindle motor.

An electrical machine having a stator and a rotor. The stator includes a core and a plurality of windings disposed on the core in a multiple-phase arrangement. The rotor is disposed adjacent to the stator to interact with the stator. A method of operating the motor includes applying a pulsed voltage differential to first and second terminals of the windings resulting in movement of the rotor; monitoring the back electromotive force (BEMF) of the windings to sense rotor movement; after the applying and monitoring steps, monitoring the BEMF of the windings to determine whether the rotor is rotating in a desired direction, and electrically commutating the motor when the rotor is rotating in the desired direction and zero or more other conditions exist.

A motor including an outside rotor having a rotor disc with plural magnets alternating polarities flush mounted in the disc, an inside stator assembly with a ring of pole pieces forming a channel to house a transversely wound stator windings, and a controller coupled with feedback electronics for monitoring a timing, speed and direction and coupling a signal to a processing unit for adjusting the drive electronics driving the phase windings. A u-shaped gap above the channel to receive the rotor disc and focus the captured magnetic flux in the pole pieces toward the magnets. In an embodiment the molded magnetic flux channel pole pieces of the inside stator are sets of molded magnetic flux channel pole pieces, each set forming a channel and corresponding to one phase of the motor; and a section of each one of the transverse windings passing through one channel, the remaining section folding back outside the set in close proximity to the outer base of the set of molded magnetic flux channel pole pieces.

In a discharge control section of an inverter control device, when the connection of the battery and the smoothing capacitor is disconnected by means of a contactor, the charge accumulated on the smoothing capacitor is discharged by applying high-frequency voltage to the stator windings of the motor by controlling the main inverter circuit.

The invention provides a method, device and system for controlling a PMSM (Permanent Magnet Synchronous Motor) to put into operation again at the belt speed. The counter EMF of the PMSM is obtained by the speed of a trailer, and is compared with the voltage on the inverter side, if the counter EMF is higher than the voltage on the inverter side, the PMSM is not allowed to be put into operation again at the belt speed, otherwise, the PMSM is put into operation again at the belt speed. When the PMSM is allowed to be put into operation again at the belt speed, a separation contactor is closed; when the PMSM is not allowed to be put into operation again at the belt speed, the separation contactor is switched off. Therefore, the method, the device and the system can be used for computing the rotor position angles through dividing the working conditions into low-speed working conditions and medium-high speed working conditions according to Omega e, and the PMSM is started through the rotor position angles; the overall control method is provided from the view of system, the PMSM at the high speed section is not allowed to be put into operation again at the belt speed, the position for the PMSM at the medium-high speed section to be put into operation again is determined through adopting a one-step short-circuit method to compute the rotor position angles, the position for the PMSM at the low speed section to be put into operation again is determined through adopting an INFORM (Indirect Flux detection by On-line Reactance Measurement) method to compute the rotor position angles.

A device is provided for detecting inadequate electric braking and commutation to a safety brake is intended for a vehicle with electric traction, in particular a rail vehicle, which is provided with a traction chain, the system including a first electric, non-safety brake which is integrated in the traction chain and a second safety brake.The device includes a member for commutation from the first brake to the second brake, a device for monitoring the braking performance of the first brake using data for measurement of the intensity of a current, a decision device for commutating from the first brake to the second brake when a predetermined threshold value is exceeded and a device for transmitting a commutation command to the at least one commutation member.

A method controls an electric vehicle which is so constituted as to drive a synchronous motor by way of a switch and an inverter circuit. A battery acts as a source of driving a controlling power. The synchronous motor has a permanent magnet acting as an outer rotor. The method includes the following operations of:1) detecting that the electric vehicle has an acceleration signal of zero;2) detecting that an actual speed of the electric vehicle is less than a predetermined percent of a rated speed;3) supplying a current to a winding of a fixed phase of the synchronous motor, by way of the inverter circuit; and4) generating a braking force.

A two-stranded electronically commutated DC motor has a permanent-magnet rotor (36), power supply terminals (28, 30) for connecting the motor to a current source (22) and a stator (102) having a winding arrangement which includes first and second winding strands (52, 54). The latter are controlled by respective first and second semiconductor switches (70, 80). The motor also has a third controllable semiconductor switch (50), arranged in a supply lead from one of the terminals (28, 30) to the winding strands (52, 54), which third switch is alternately switched on and off by applying to it a PWM (Pulse Width Modulated) signal 24. During switch-off intervals, magnetic flux energy stored in the motor causes a decaying loop current (i2) to run through the windings, continuing to drive the rotor. This facilitates conformal mapping of temperature information in the PWM signal onto a target motor rotation speed.

The invention relates to a motor device of a top opening barrel washing machine for accurately halting and positioning. A washing barrel of a washing machine consists of an outer barrel positioned on an outer layer and an inner barrel positioned in the outer barrel; both the inner barrel and the outer barrel are positioned in the shell of the washing machine; a motor is arranged beside the inner barrel and drives the inner barrel to rotate; a locking piece is arranged on the inner wall of the outer barrel; the motor is provided with a controller for controlling the locking piece to be at the locking position; and the inner barrel is controlled by the controller to be kept at a position in which clothes and articles are put into or taken out. A small block of magnetic steel is additionally arranged on a motor rotor and matched with a fourth Hall sensor on a motor stator, thus the motor can stop in the same posture; and when a direct current brushless motor is used on the top opening washing machine, the cover-opening position of the inner barrel faces upward and stops at the position at which the clothes and articles are put into or taken out by people, thereby realizing the humanized design of the washing machine and enabling the operation of the washing machine to become simple, comfortable and convenient.

A motor driving apparatus includes a pulse-width modulator and a PWM frequency switch for switching a carrier frequency of the modulator. The PWM frequency switch changes a carrier frequency in a start-up period of the motor to another frequency when the motor enters into a regular rotation. The carrier frequency in the start-up period is set at a lower level than that in the regular rotation period, so that the driving apparatus can reduce power-loss generated in the start-up period by switching actions of respective driving elements forming a first and a second drivers. In the regular rotation period, the driving apparatus performs PWM-driving with a high enough carrier frequency, so that the motor driven by this driving apparatus can realize accurate rotation.

Provided is a motor control circuit for controlling the energization of a coil on the basis of the detection result of the position of a rotor. The motor control circuit performs controls to make a stop for a short time by suppressing continuous rotations by inertia and to cause no reverse rotation. When an external control signal (CTL) changes from L to H, a steady rotation control changes to a reversing control so that a reversing brake state comes in. The rotating speed of the motor is monitored, and when the rotating speed attenuates to a set rotating speed, a brake control signal (SPSB) changes from L to H so that a short brake state comes in. However, the motor is caused to continue rotations by inertia, and a position detecting signal (HALL) changes, so that the reversing brake control is performed temporarily (for a time period corresponding to a pulse width (TRB)). This short-pulse reversing brake control is interruptedly performed till the motor stops completely. Thus, the stop can be done for a shorter time period than in the case in which the stop is done only by the short brake control after the motor was decelerated to a rotating speed just before the stop.

A motor including an outside rotor having a rotor disc with plural magnets alternating polarities flush mounted in the disc, an inside stator assembly with a ring of pole pieces forming a channel to house a transversely wound stator windings, and a controller coupled with feedback electronics for monitoring a timing, speed and direction and coupling a signal to a processing unit for adjusting the drive electronics driving the phase windings. A u-shaped gap above the channel to receive the rotor disc and focus the captured magnetic flux in the pole pieces toward the magnets. In an embodiment the molded magnetic flux channel pole pieces of the inside stator are sets of molded magnetic flux channel pole pieces, each set forming a channel and corresponding to one phase of the motor; and a section of each one of the transverse windings passing through one channel, the remaining section folding back outside the set in close proximity to the outer base of the set of molded magnetic flux channel pole pieces.

The present invention provides apparatus, systems and methods for fail passive servo controllers. In accordance with an exemplary embodiment of the present invention, servo controller is used with an ALS to control an aircraft during landing procedures. In accordance with one aspect of this exemplary embodiment, upon a failure (e.g., of one of the components of ALS) servo controller fails passively rather than actively. In an exemplary embodiment, the fail passive nature of the servo unit is accomplished by providing at least two independent signal and drive current paths for controlling the servo motor. As such, the servo motor will not generate torque unless the two independent signal lanes agree. For example, when a component such as processor, difference amplifier, or PWM fails or otherwise ceases to function properly, servo motor will not runaway, but rather will fail with only minor transient movement, or alternatively, servo unit will lock at its current position. In this manner, servo motor will not generate a deviation from flight path or other significant control inputs until system monitors detect the fault and return control to the pilot.

The invention discloses a brushless direct current motor-assisted electric power steering controller and a control method thereof. An MC33034P120 driving integrated chip is connected in series with the rear end of a microprocessor; the output of the driving integrated chip is connected with a power bridge; the output of the power bridge is connected with a brushless direct current motor and a current feedback and protection module respectively; the current feedback and protection module is connected with a feedback current signal processing module; the output of the feedback current signal processing module is connected in series between the microprocessor and the driving integrated chip to form a closed-loop control loop; and the microprocessor determines a driving condition of an automobile according to a steering wheel torque signal, a corner signal and a speed signal and controls the driving integrated chip to drive the brushless direct current motor to realize automobile power-assisted control, return control and damping control. In the invention, phase conversion of the brushless direct current motor is realized by using the driving integrated chip, so the burden of the microprocessor is relieved, the control real-time property is enhanced, a stop or out-of-step situation of the motor is avoided, and the safety of motor driving is improved.

A method controls an electric vehicle which is so constituted as to drive a synchronous motor by way of a switch and an inverter circuit. A battery acts as a source of driving a controlling power. The synchronous motor has a permanent magnet acting as an outer rotor. The method includes the following operations of: 1) detecting that the electric vehicle has an acceleration signal of zero; 2) detecting that an actual speed of the electric vehicle is less than a predetermined percent of a rated speed; 3) supplying a current to a winding of a fixed phase of the synchronous motor, by way of the inverter circuit; and 4) generating a braking force.

A system and method are presented for aligning a rotor in a motor. The motor may include the rotor and a plurality of pairs of electromagnets. One or more pairs of electromagnets may be excited at a first excitation level. The one or more pairs of electromagnets may be less than all of the plurality of pairs of electromagnets. The excitation of the one or more pairs of electromagnets may be increased to a second excitation level over a first period of time. The excitation of the one or more pairs of electromagnets may be decreased to a third excitation level over a second period of time. Exciting the one or more pairs of electromagnets, increasing the excitation, and decreasing the excitation may cause the rotor to stop in a known position.

During normal operation of a hard disk drive, control logic controls a plurality of switching elements to provide electrical power to a spindle motor and head motor of the disk drive from a voltage source coupled to first and second voltage supply nodes (e.g., Vcc and ground), the spindle motor has a set of motor windings to which the electric power is applied to rotate the spindle motor, and the control logic is configured to enter a regenerative braking state during normal operation where the switching elements are controlled to isolate the spindle motor from the first voltage supply node and cause regenerative braking of the spindle motor so that kinetic energy due to rotation of the spindle motor is converted to electrical power that is supplied to the head motor by virtue of inductance of one or more motor windings in the set.

A driving system for driving a brushless motor effects a rotation control of a rotor by sequentially switching application of a current to magnetic coils disposed in a stator in response to a detection signal from a pole-position detector. The driving system comprises a controlling circuit for generating a driving signal, an inverter control circuit for controlling application of the current to the coils by adjusting opening and closing of switching devices in response to the driving signal, and a rotational speed sensor. The controlling circuit generates a braking signal when a rotational speed of the rotor is beyond a predetermined value, and transmits the braking signal to the inverter control circuit. The inverter control circuit effects a braking control in response to the braking signal by application of the current to at least one coil except those coils being excited upon reception of the braking signal.

A drive device has a break circuit. The break circuit inputs phase-current values transferred from phase-current sensors mounted on an electrical path of a motor generator. A power switching element is equipped with a freewheel diode connected in parallel with each other. An inverter has pairs of the power switching elements. In each pair, the power switching element in a high voltage side and the power switching element in a low voltage side are connected in series. It is detected for the freewheel diode to be in a freewheel mode when a forward current flows in the freewheel diode. The break circuit detects the freewheel mode when the phase-current value is not less than a predetermined threshold value. The break circuit detects the freewheel mode where the current flows in the freewheel diode in an upper arm when the phase-current value is not more than the threshold current value.

A motor drive apparatus 1 having a dynamic braking circuit 5 for producing a deceleration torque utilizing a braking force caused by a synchronous motor 4 acting as a generator when the synchronous motor 4 is deenergized, is equipped with a dynamic braking circuit fault detection capability, and comprises: a DC power supply 2 which is obtained by rectifying input AC power; voltage application means 2, 3, 10, 11 for applying a voltage to the windings of the synchronous motor 4 and to the dynamic braking circuit 5 for a predetermined length of time by switching power transistors A to F connected to the DC power supply 2; current detection means 6 for detecting the value of a current flowing from the power transistors A to F; and fault checking means 11 for checking the dynamic braking circuit 5 for the presence or absence of a fault, based on the current value detected by the current detection means 6 and on a predefined threshold value. With this configuration, detection of faults in the dynamic braking circuit is accomplished without requiring the addition of a contact signal or a control circuit.

The invention relates to a system for detecting insufficient electric braking and converting to a safe brake. The system is used for a vehicle drawn by electric power, in particular for a rail vehicle provided with a drawing chain (1). The system comprises a first electric unsafe brake and a second safe brake (2, 117) integrated in the drawing chain (1). The system is characterized in that the system comprises a component (20) for converting from the first brake to the second brake (2, 117), a device (3) monitoring braking performance of the first brake by using data for measuring current intensity, a judging device (4) for converting the first brake into the second brake (2, 117) when a predetermined threshold value (240) is surpassed, and a device (5) transmitting conversion instructionto at least one converting component.

The invention relates to a magnetic suspension reaction fly-wheel motor control system, which is mainly composed of a Cuk ascending and descending pressure converter, a permanent magnet brushless direct current motor, a three-phase star type half bridge, a digital controller, an energy consumption unit and other components. The system sends a detected position signal to the digital controller through a position measurement device, and the detected position signal is transformed into a PWM signal through the digital controller and is output to control the transformation ratio of the Cuk ascending and descending pressure converter, and the phase conversion and the speed adjustment of the energy consumption unit and the permanent magnet brushless direct current motor. The magnetic suspension reaction fly-wheel motor control system can carry out ascending and descending pressure conversion to steady direct current power supply voltage and can drive the permanent magnet brushless direct current motor according to rotation speed changes on rear time under the condition that input voltage is not changed, the phase conversion of the permanent magnet brushless direct current motor is controlled by the three-phase star type half bridge, the system dynamic performance is improved through increasing the output force moment factors of the permanent magnet brushless direct current motor and expanding the maximum accelerating moment of a magnetic suspension reaction fly wheel, simultaneously, total power consumption is not increased, and the magnetic suspension reaction fly-wheel motor control system has important application value to aerospace crafts with limited electric energy.

A method of controlling a power converter (20) of a motor drive system (10)controls the power converter (20) during a first operating mode by applying a current control scheme, which sets power converter commands to control torque current flowing from the power converter (20) to the motor (30) to achieve desired motor speed; and initiates a second operating mode when power supply to the power converter (20) is interrupted. The second operating mode includes controlling negative torque current between the power converter (20) and the motor (30) so that mechanical energy from the motor (30) charges an element (58) on a power supply side of the power converter (20). The first operating mode is resumed when the input power recovers. Torque current between the power converter (20) and the motor (30) is also controlled to limit a maximum transient DC bus voltage.

An electrical machine having a stator and a rotor. The stator includes a core and a plurality of windings disposed on the core in a multiple-phase arrangement. The rotor is disposed adjacent to the stator to interact with the stator. A method of operating the motor includes applying a pulsed voltage differential to first and second terminals of the windings resulting in movement of the rotor; monitoring the back electromotive force (BEMF) of the windings to sense rotor movement; after the applying and monitoring steps, monitoring the BEMF of the windings to determine whether the rotor is rotating in a desired direction, and electrically commutating the motor when the rotor is rotating in the desired direction and zero or more other conditions exist.

Provided is a motor having a magnetic polar unit in which a permanent magnetic polar array having arranged therein alternately a plurality of permanent magnetic polar elements in alternate opposite poles is made to face a plurality of electromagnetic coil arrays alternately excited at opposite poles, and the permanent magnetic polar array is made to move thereby; wherein the motor further comprises a sensor for detecting the periodical magnetic change accompanying the movement of the permanent magnetic polar array, the output of the sensor is directly returned as a direct drive waveform to the electromagnetic coils, and this drive circuit forms the excitation signal based on the return signal.

A traction drive, in particular for rail cars, includes a permanent-excited synchronous motor, a traction converter with a pulsed inverter for powering the motor, and ohmic brake resistors. Cross-over switches are connected with a corresponding input terminal of the motor and can switch the input terminal between a corresponding output terminal of the pulsed inverter (for travel) and a terminal of a corresponding brake resistor (for braking). The brake resistors are electrically connected in a star configuration. The traction drive can operate with different supply voltages. There is no longer a need for a mechanical brake, and flat spots on the wheels can be prevented.

The invention relates to a motor drive system and an energy feedback brake control method of the motor drive system. The motor drive system comprises a storage battery, a motor controller and a permanent magnet brushless direct current motor. The motor controller comprises a control module and a triphase full-bridge inversion circuit, wherein the control module comprises an electric control unit and a brake control unit; the brake control unit is used for confirming a first upper half bridge switch tube and a second lower half bridge switch tube turned on by a wave transmission sequence corresponding to a position signal of the current rotor in the electric control process when brake is conducted, and sending a PWM (pulse-width modulation) signal to control the on and off of the first lower half bridge switch tube corresponding to a branch where the first upper half bridge switch tube is located, so that a return circuit is formed to generate brake current in a motor coil, and the storage battery is charged. According to the system and the method, half bridge modulation energy feedback can be conducted according to a reversibility principle of the motor in the brake process of the permanent magnet brushless direct current motor, and the service time of the storage battery can be prolonged.

In a motor-driven shift position switching device, when the difference between a target position and the rotation position of a rotor has become smaller than a prescribed value in a motor feedback control, a transition is made to a deceleration control. A phase lead correction amount for correcting the phase lead of the current supply phase with respect to the rotor rotation phase is set in accordance with the rotor rotation speed. Thus, proper braking force suitable for the rotor rotation speed is exerted on the rotor and the rotor can be decelerated smoothly as it approaches the target position. Further, in the period when the current supply to the motor is kept off, the shift position switching determination ranges are set wider than in the period when the current supply to the motor is on.