458 results about "Dynamic braking" patented technology

A railroad vehicle (1500) for carrying freight is described. The railroad vehicle (1500) comprises power regeneration capability through a traction motor (1530) linked to a driving wheel (1520D), an electrical energy storage system (1550), a controller (1570) that may selectively operate the traction motor (1530) in a motoring mode, a coasting mode, or a dynamic braking mode. In the dynamic braking mode electrical energy from the traction motor (1530) is transmitted to the electrical energy storage system (1550). The controller (1570) is in communication with a communication link (1580) that receives control commands from an external control source (1595), and those control commands indicate the operating mode for a particular period of time.

A self-powered railroad system (1700), in one embodiment, comprises a locomotive (1710), a control source (1715), and a plurality of load units (1720A-K and 1730A-G), some of which are railroad vehicles (1720A-K) comprising the components of railroad vehicle (1500) that provide for selective operation in a motoring mode, a coasting mode, or a dynamic braking mode. The self-powered railroad system may also comprise a control source and at least one railroad vehicle controlled by the control source, such as for coupling, uncoupling, and moving to or from a loading dock.

An apparatus for electric braking and system protection for an electric generator includes a dynamic brake and a crowbar circuit designed for cooperation with power converters to dump power upon command. The dynamic brake includes at least one resistor and the crowbar circuit includes another at least one resistor for dissipating power from the electric generator. Methods for use of the electric braking and system protection calls for shunting the power to at least one of the dynamic brake, the crowbar circuit and the generator side power converter.

A hybrid energy railway vehicle system having a traction motor with a dynamic braking mode of operation for dynamically braking the traction motor and for generating dynamic braking electrical energy and an electrical energy storage system that is in electrical communication with the traction motor and that stores dynamic braking electrical energy generated by the traction motor. The system also has a hybrid energy railway vehicle with a plurality of wheels wherein the traction motor has a motoring mode of operation for driving one of the wheels in response to electrical input energy. A converter selectively provides stored electrical energy from the energy storage system to the traction motor as electrical input energy for driving one or more of wheels. The hybrid energy railway vehicle is optionally equipped computer readable medium having computer executable instructions for controlling the operation of the hybrid energy railway vehicle and a processor configured to control the operation of the railway vehicle as a function of at least one of a plurality of operating modes.

A method and system for dissipating energy in a direct current (dc) bus of a doubly-fed induction generator (DFIG) converter during a grid event is described. In one aspect, the method comprises monitoring operating conditions of an electrical system, the electrical system comprising at least a DFIG generator and a line side converter and a rotor side converter connected by a dc bus having a dynamic brake connected thereto; detecting an overvoltage on the dc bus or a condition indicative of an overvoltage on the dc link is detected, the overvoltage on the dc bus or condition indicative of the overvoltage caused by a grid event; and causing energy in the dc link to be dissipated using the dynamic brake.

A system for aftertreatment of diesel engine exhaust on a vehicle which is equipped for dynamic braking, using the electrical power generated by the dynamic braking to energize a resistor bank which incinerates particulate matter which has been collected in a particulate matter filter, thereby regenerating the filter.

The invention relates to an urban tram braking system. The system comprises a braking instruction generation system, a braking control system and an anti-skid system, wherein the braking instruction generation system comprises a braking electronic control unit (BECU) and a braking control unit (BCU) and sends a braking instruction to the BECU; the BECU calculates required braking force according to the braking instruction and loading force detected by a loading pressure sensor and provides the braking force for a traction control unit; the traction control unit feeds a dynamic braking force signal back to the BECU; the BECU calculates air braking force which is needed to be supplemented and controls the BCU to generate braking cylinder pressure so as to realize braking control; the braking instruction generation system is provided with a driver controller, an emergency braking switch and a logic control unit connected with the emergency braking switch; the anti-skid system comprises a speed sensor arranged on a wheel axle and an anti-skid exhaust valve arranged on a braking cylinder pipe; the speed sensor detects a speed signal and transmits the speed signal to the BECU; and the BECU controls the action of the anti-skid exhaust valve according to the speed signal.

Current source converter (CSC) based motor drives and control techniques are presented in which DC link current is regulated to a level set by the output inverter during dynamic braking operation by pulse width modulation of a braking resistance connection signal to maintain control of motor torque and speed while mitigating or preventing line side regenerative currents.

A power tool is a “low profile” power tool, that is the overall height of the power tool is sufficiently small that a user can grasp the top of the power tool with the user's hand and the hand will be positioned relative close to the bottom of the power tool compared with existing power tools. The low profile power tool uses a low profile motor having a diameter to lamination height ratio of at least 2:1. In an aspect of the invention, the motor is an electronically commutated “pancake” style motor. In an aspect of the invention, the power tool is a random orbital sander or an orbital sander having a motor that provides at least 40 watts of power. In an aspect of the invention, the sander has a mechanical brake that brakes the orbital mechanism and the motor is dynamically braked.

A computerized system for use in connection with a hybrid energy off highway vehicle system of a off highway vehicle. The hybrid energy off highway vehicle system includes an off highway vehicle, a primary power source, and an off highway vehicle traction motor propelling the off highway vehicle in response to the primary electric power, and an energy capture system for storing and/or transferring electrical power. An energy management processor carried on the off highway vehicle controls transmission of electrical power among the primary electric power generator, the vehicle propulsion system, an electrical energy capture system, and each of the plurality of dynamic braking resistance grid circuits during motoring, operating and braking the travel of the off highway vehicle.

The present invention involves a dynamic brake for use in a peristaltic (i.e., roller) pump. The dynamic brake avoids backlash, due to counter rotation. In addition, it does not preclude the option of hand operating the roller pump. This is achieved by initiating the braking operation after the roller pump set-point has been set to zero and only after the roller pump has decelerated below a predefined speed (e.g., 20 rpm). In addition, the braking operation is activated for only a very brief period of time (i.e., a period of time required for the pressure in the roller pump fluid conduit to subside).

A motor power supply having an inrush current protection mode, a motor drive mode, an overvoltage protection mode, and a dynamic braking mode. In the inrush protection mode, a first resistance limits an inrush current to a capacitor which smoothes a rectifier output to provide DC power to an inverter during the motor drive mode. In the overvoltage protection mode, the first resistance is used in conjunction with a switching element to controllably discharge an overvoltage which may occur across the capacitor due to regenerated energy from the motor passing back through the inverter. During the drive mode, the inverter input is connected with the DC power and during the dynamic braking mode, the inverter input is connected with a second resistance which dissipates the energy regenerated by the motor. A controller controls a multi-contact relay and the switching element to implement the various modes of operation.

A method for controlling a railroad train (10) comprising a lead unit (14), a remote unit (12A) and a communications system communicating information between the lead unit (14) and the remote unit (12A), wherein the lead unit (14) and the remote unit (12A) are each operable in a traction operational mode and a dynamic brake operational mode. The method comprises determining operability of the communications system; determining a direction of train travel; determining an operational mode of the lead unit (14) and the remote unit (12A); and indicating a train condition responsive to the operability of the communications system, the direction of train travel and the operational mode of the lead (14) and remote units (12A).

A hybrid energy railway vehicle system having a traction motor with a dynamic braking mode of operation for dynamically braking the traction motor and for generating dynamic braking electrical energy and an electrical energy storage system that is in electrical communication with the traction motor and that stores dynamic braking electrical energy generated by the traction motor. The system also has a hybrid energy railway vehicle with a plurality of wheels wherein the traction motor has a motoring mode of operation for driving one of the wheels in response to electrical input energy. A converter selectively provides stored electrical energy from the energy storage system to the traction motor as electrical input energy for driving one or more of wheels. The hybrid energy railway vehicle is optionally equipped computer readable medium having computer executable instructions for controlling the operation of the hybrid energy railway vehicle and a processor configured to control the operation of the railway vehicle as a function of at least one of a plurality of operating modes.

A braking system for a wind turbine is disclosed. The braking system may include a DC chopper connected to a DC bus and a super capacitor capable of being connected to the DC chopper through a switch. The DC chopper may be controlled by a control system to enable one of charging, discharging, idle or system off modes of the super capacitor.