MOTOR BRAKING USING SELECTIVELY CONNECTABLE RESISTANCE

    公开(公告)号:US20240186919A1

    公开(公告)日:2024-06-06

    申请号:US18440369

    申请日:2024-02-13

    摘要: Apparatus and method for motor braking using selectively connectable resistance. The method includes controlling, using a motor controller of the power tool, a power switching network to drive a motor of the power tool in response to actuation of a user input and determining, using the motor controller, a variable tool characteristic. The method further includes determining, using the motor controller, that the user input is de-actuated. The method also includes controlling, using the motor controller, the power switching network to brake the motor when the variable tool characteristic satisfies the tool characteristic threshold and controlling, using the motor controller, a braking circuit to brake the motor when the variable tool characteristic does not satisfy the tool characteristic threshold. The braking circuit includes one or more resistive loads and is selectively coupled to the motor terminals of the motor.

    Regenerative Braking Power Generation System for Trailers

    公开(公告)号:US20240157804A1

    公开(公告)日:2024-05-16

    申请号:US17772954

    申请日:2022-03-31

    IPC分类号: B60L7/16 B60T13/74 H02P3/14

    摘要: Disclosed is a regenerative braking power generation system for trailers configured such that a generator is installed in a brake disc space portion of a trailer to self-generate electricity necessary for the trailer, wherein the regenerative braking power generation system includes at least one axle (3) fixed to a chassis (2) of a trailer, a wheel hub (5) and/or a brake disc (6) axially installed at an outer surface of the axle (3) via a plurality of bearings (4) so as to be passively rotated, a space portion (7) concavely formed in one side surface of the brake disc (6), a permanent magnet (8) fixed to an inner circumferential surface of the space portion (7) in tight contact therewith, the permanent magnet being configured to be rotated along with the brake disc (6), and a generator stator (9) fixed to an outer circumferential surface of the axle (3) corresponding to the permanent magnet (8). AC power produced by the generator (10) is converted into DC power by a rectification unit (20) constituted by a plurality of full-wave diodes (D1, D2, D3, D4, D5, and D6) and a smoothing capacitor (C), a rechargeable battery (secondary battery) or a battery (40) is charged with the DC power by a charge controller (30), the DC power is supplied to a DC (direct current) load (50), and the power in the battery (40) is converted into AC power of 50 to 60 Hz by an inverter (60) and is supplied to an AC (alternating current) load (70).

    CORDLESS SAW HAVING IMPROVED CUTS PER BATTERY CHARGE

    公开(公告)号:US20240009882A1

    公开(公告)日:2024-01-11

    申请号:US18219388

    申请日:2023-07-07

    摘要: A cordless aw is provided with regenerative braking means that increases the number of repeated cuttings the saw is able to perform (x) per full discharge cycle of the battery pack, as compared to the number of repeated cuttings achievable by the same saw not employing a regenerative braking means (y) per full discharge cycle of the battery pack, such that x/y is approximately at least one of the following: i) 1.1 when cutting a Pressure-Treated (PT) lumber workpiece having a cross-sectional size of approximately 89 mm×89 mm±2 mm, ii) 1.15 when cutting a Spruce Pine Fir (SPF) lumber workpiece having a cross-sectional size of approximately 38 mm×89 mm±2 mm, or iii) 1.25 when cutting Medium Density Fiberboard (MDF) workpiece having a thickness of approximately 19 mm±1 mm and a width of approximately 76 mm±2 mm.

    Method for controlling an electric motor

    公开(公告)号:US11682988B2

    公开(公告)日:2023-06-20

    申请号:US17685258

    申请日:2022-03-02

    发明人: Libo Zheng Min Zhang

    IPC分类号: H02P1/46 H02P3/14 H02P1/02

    CPC分类号: H02P1/46 H02P1/029 H02P3/14

    摘要: A method is described for controlling an electric motor having a rotor. The method is carried out after a shutdown of the motor has been initiated. The method includes starting a timer in a motor controller, performing regenerative braking to recapture kinetic energy from the rotor as electrical energy, and using the recaptured electrical energy from the regenerative braking to power the motor controller. If the timer in the motor controller exceeds a predetermined timer value, a flag is set in memory in the motor controller to indicate that the motor has stopped.

    Controlling regenerative braking to reduce skidding of a vehicle

    公开(公告)号:US11673474B2

    公开(公告)日:2023-06-13

    申请号:US16731360

    申请日:2019-12-31

    申请人: Textron, Inc.

    摘要: A technique controls regenerative braking to reduce skidding of a vehicle. Such a technique involves imparting rotation to an alternating current (AC) electric motor to move the vehicle to a first commanded vehicle speed; applying a regenerative braking power to the AC electric motor to bring the vehicle to a second commanded vehicle speed; while applying the regenerative braking power, adjusting the level of regenerative braking power applied to follow a predetermined speed reduction rate; while adjusting the level of regenerative braking power applied, provide a limit to the maximum level of regenerative braking power available; and while providing the limit to the maximum level of regenerative braking power available, adjusting the limit to the maximum level of regenerative braking power available based on a current speed of the vehicle.

    Motor output stabilizing circuit and method

    公开(公告)号:US11437946B2

    公开(公告)日:2022-09-06

    申请号:US17115795

    申请日:2020-12-09

    IPC分类号: H02P3/14 H03K5/24 H02P23/14

    摘要: A motor output stabilizing circuit and a method are provided. A sensor senses a positive voltage and a negative voltage that are generated with a change in magnetic field strength of a motor of which a rotor is rotating. A comparator compares the positive voltage with the negative voltage to output a Hall signal. An average counter records a first time during which the positive voltage is higher than the negative voltage and a second time during which the negative voltage is higher than the positive voltage, according to the Hall signal. The average counter then averages the first time and the second time to output an averaged time signal. A motor controller circuit controls a motor driver circuit to drive the motor according to the averaged time signal, such that the motor outputs a constant current.