Showing papers on "Dynamic braking published in 2003"

Coordinated brake control system

Abstract: A coordinated brake control system is for a hybrid brake system including a regenerative brake unit and a friction brake unit for a vehicle and is arranged to generate a total braking torque which is a combination of a regenerative braking torque generated by the regenerative brake unit and a friction braking torque generated by the friction brake unit, so as to bring the total braking-torque closer to a target braking torque, and to limit a rate of change of the regenerative braking torque according to a response delay of the friction braking torque when a first distribution ratio of the generative braking torque relative to the total braking torque is decreased and when a second distribution ratio of the friction braking torque relative to the total braking torque is increased

Hybrid energy off highway vehicle electric power storage system and method

Abstract: An electrical energy capture 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. The off highway vehicle traction motor has a dynamic braking mode of operation generating electrical energy. The electrical energy capture system includes an energy management processor carried on the off highway vehicle. The capture system also includes an off highway vehicle electric generator connected to and driven by the primary power source for selectively supplying primary electric power, wherein the generator is responsive to said processor. An electrical energy storage device is carried on a off highway vehicle and is in electrical communication with the off highway vehicle traction motor. The storage device is responsive to the processor, selectively stores electrical energy generated in the dynamic braking mode, and selectively provides secondary electric power from said stored electricity electrical energy to the off highway vehicle traction motor. The off highway vehicle traction motor is responsive to the secondary electric power. The processor provides a first control signal to the electrical energy storage device to control the selective storing of the electrical energy generated in the dynamic braking mode, and to control the selective providing of secondary electric power to the off highway vehicle traction motor. The processor also provides a second control signal to the generator for controlling the selective supplying of primary electric power to the off highway vehicle traction motor.

Automatic braking apparatus generating braking force in accordance with driving condition of driver

Abstract: A brake control ECU of an automatic braking apparatus calculates an awareness level in accordance with: whether or not there are a braking pedal or accelerator pedal operations; whether or not there are shift and steering wheel operations; and whether a level of a driver's eye movement lowers. When the brake control ECU determines that the awareness level has decreased, it controls the hydraulic braking apparatus so as to increase a provision braking force applied for a certain period and with a certain cycle to each wheel 4 FR, 4 FL, 4 RR, 4 RL. Accordingly, vibration caused by increase and decrease of the braking force is generated in a body of a vehicle that is running. This vibration arouses the driver whose level of consciousness has decreased.

Regenerative braking system for an electric vehicle

Abstract: A regenerative braking system for an electric vehicle having front and rear wheels, and includes a drive wheel, an actuating device, a regenerative braking control circuit (64)includes a potentiometer or transducer (40) a process sensor (66), and a microprocessor (118). The system applies a regenerative braking torque to the drive wheel when the rider commands regenerative braking, and the process sensors (66) signal a drive wheel velocity greater than zero. The present invention also relates to a throttle (22) for actuating regenerative braking and reversing feature.

Motor power supply

Abstract: 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.

Vehicle braking apparatus

Abstract: A vehicle braking apparatus is provided that basically comprises a hydraulic braking apparatus, an electric braking apparatus and a regenerative braking apparatus. The hydraulic braking apparatus is configured and arranged to apply a hydraulic braking force on at least one first wheel subject to a first braking system. The electric braking apparatus is configured and arranged to apply an electric braking force on at least one second wheel subject to a second braking system that is different from the first braking system. The regenerative braking apparatus is configured and arranged to apply a regenerative braking force on one of the first and second wheels subject to a corresponding one of the first and second braking systems. The vehicle braking apparatus enables the battery for an electric braking apparatus to be more compact while also enabling regenerated electric power to be used for braking.

Vehicle braking control system

Abstract: A vehicle braking control system is provided that controls at least three braking devices including a regenerative braking device (9R and 9L), a hydraulic braking device (5R and 5L),and an electric braking device (7R and 7L). The vehicle braking control system basically comprises a braking mode selecting section (15 and S4), a required braking force determining section (S3),and a target braking force setting section (SS-S15). The braking mode selecting section (15 and S4) sets one of a plurality of braking modes having a different braking control priority for each of the target braking forces. The required braking force determining section (S3) determines a required braking force for an entire vehicle (1). The target braking force setting section (S5-S15) sets each of the target braking forces based on the braking control priority of the selected braking mode to produce the required braking force for the entire vehicle (1). Preferably, the braking mode selecting section (15 and S4) sets at least an electric power maintenance priority mode and a braking response priority mode.

Electric vehicle braking system

Abstract: A braking system for electric vehicles that gives a driver the feel of a conventional hydraulic braking system while maximizing the recuperation of electrical power is described herein. A single brake pedal is used to control both electric and hydraulic braking assemblies. A feedback force generator is provided to give the driver the impression that a completely hydraulic braking system is used. Therefore, the driver is not inclined to further depress the pedal, thereby preventing the premature activation of the hydraulic braking system.

Method and apparatus for adaptive control of vehicle regenerative braking

Abstract: A hybrid electric vehicle having an energy generation system, an energy storage system and at least one electric motor includes a controller for controlling operation of vehicle systems. The controller monitors the status of vehicle systems and system parameters and determines the regenerative braking mode of the vehicle and the appropriate level of regenerative braking for proper vehicle operation. The controller generates commands based upon these determinations to produce regenerative braking, monitors the status to determine the effects of the regenerative braking command generated, and adaptively changes the regenerative braking command generated in response to the measured effects. A method for adaptively controlling a hybrid electric vehicle is also provided.

Method and apparatus for power management of a regenerative braking system

Abstract: A vehicle braking system and method of control is disclosed which includes electromagnetic and friction braking functionality. The electromagnetic braking system includes a generator which supplies power to eddy current devices. Accordingly, the eddy current devices apply a retarding torque on the wheels of the vehicle. In the event the generator produces an amount of power greater than that needed by the electromagnetic braking system, the generator will supply power to a supplemental power source such as a battery.

Vehicle dynamics control system

Abstract: In a vehicle dynamics control (VDC) system for a four-wheel-drive vehicle employing a brake control system regulating braking forces applied to road wheels independently of each other and a differential mechanism controlling a differential motion between front and rear wheel axles, a VDC controller controls a braking force of each road wheel depending on whether the vehicle is in oversteering or understeering. The VDC controller includes a braking-force compensation section that compensates for a braking force of at least one of a first wheel, which is subjected to vehicle dynamics control, and a second wheel to which a transferred braking force is transferred from the first wheel through the differential mechanism, to reduce a braking force of the second wheel and to prevent the braking force of the second wheel from exceeding a lateral grip limit of the second wheel during the vehicle dynamics control.

Method and system for optimizing energy storage in hybrid off-highway vehicle systems and trolley connected ohv systems

Abstract: A hybrid energy system for propelling an off-highway vehicle includes an engine rated at a first power capacity, and a power converter driven by the engine for providing primary electric power. A traction motor system receives the primary electric power, the traction motor system propelling the off-highway vehicle in response to the primary electric power, and the traction motor system further including a dynamic braking mode of operation. An energy storage medium captures electrical energy generated by the traction motor system in the dynamic braking mode of operation, the energy storage medium transferring a portion of the captured energy to the traction motor system to augment the primary electric power, wherein the traction motor system is rated at a second power capacity exceeding the first power capacity.

Model regulator based individual wheel braking control

Abstract: Yaw stability control systems are important components of active safety systems for road transport. A model regulator based yaw stability control system that was previously implemented and tested very successfully as a steering controller is adapted to work as an individual wheel braking controller in this paper. A two track nonlinear vehicle model is used to test the individual wheel braking actuated model regulator developed here. Simulation results are used to demonstrate the achievement of good yaw disturbance moment rejection by the proposed controller.

Braking system and braking control method

Abstract: A brake system for a multi-axle vehicle is described which includes a plurality of brake elements for applying a required braking force to the vehicle in response to a brake command and a controller which monitors operation of the brake elements and on detection of a reduction of effectiveness of one brake element, distributes the associated loss of braking force between the remaining brake elements. The system is advantageously employed where a number of individually operable units or vehicles are to be configured to form a train. Each unit is provided with its own unit controller, which provides configuration information to the other controllers concerning the number of units in the train and their respective brake systems.

Motor control apparatus and control method thereof

Abstract: A motor control apparatus supplying AC power to a motor having a plurality of motor windings having an inverting part including a bridge circuit having a plurality of switching units, and supplying the AC power to the motor; brake relays short circuiting the motor windings by turning on when the motor brakes; brake resistors, respectively, connected to the motor windings and consuming an overcurrent generated from the motor when the brake relays short circuit the motor windings; and a switching controller turning on and turning off the switching units provided in one of opposite ends of the inverting part so that the overcurrent consumed by the brake resistors is changeable in proportion to a rotation speed of the motor, when the brake relays short circuit the motor windings to improve an effect of a dynamic braking operation and to prevent breakdown thereof.

Braking system of hybrid vehicle

Abstract: A hybrid system for a vehicle which can ensure a braking stability on a slippery road is provided. Therefore, the system is provided with a motor 2 a rotation force of which is transmitted to a rear wheel 7, braking actuators 57, 67 which brake the front wheel 6 and the rear wheel 7, and proportional valves 53, 63 controlling a braking force introduced into each braking actuator 57, 67. A control unit 20 is so provided that the control unit 20 calculates a required braking energy based upon a vehicle operating condition in demanding a braking and operates the motor 2 as a power generator to generate a power so as to produce the calculated braking energy, as well as controls a braking force of the front wheel 6.

Braking force control apparatus for vehicle and method thereof

Abstract: The braking force control apparatus for a vehicle which has a function of applying a braking force to the vehicle by rotational resistance of the engine, by stopping the fuel supply to the engine during coasting of the vehicle and by controlling a torque capacity of a torque capacity control device that is provided between the engine and a wheel so that the torque capacity becomes equal to or higher than a predetermined value, and of decreasing the torque capacity of the torque capacity control device when a predetermined condition is satisfied, and has a function of applying the braking force to the vehicle by a function of an electric power generator which is coupled with the wheel such that power can be transmitted. The braking force control apparatus includes braking force control means which increases a braking force that is generated by the function of the electric power generator when the torque capacity of the torque capacity control device is decreased.

Displacement on demand with regenerative braking

Abstract: A regenerative braking system for a vehicle includes a displacement on demand (DOD) engine having cylinders, a battery, and an electric machine having motor and generator modes. The electric machine is selectively driven by a wheel of the vehicle. A controller detects a braking condition of the vehicle and deactivates at least one of the cylinders in response to the braking condition. The controller operates the electric machine in the generator mode during the braking condition to charge the battery.

Cooperation controller for composite brake

Abstract: PROBLEM TO BE SOLVED: To see that a regenerative brake torque limiting value does not change suddenly even when the velocity of a vehicle changes with the step increase or step return of a brake pedal during limitation of maximum regenerative torque. SOLUTION: This cooperation controller limits the regenerative braking torque limiting value Tmfin from Tmmax to Tmlmt(i) from the time t1 when the first critical regenerative torque Tmlmt(i) geared to the velocity (middle deceleration) of the vehicle falls under tolerable maximum regenerative braking torque Tmmax. If there is step increase of the brake pedal on and after the limitation starting time t1 (during limitation of maximum regenerative braking torque) of such maximum regenerative braking torque (t2), the first critical regenerative braking torque Tmlmt(i) drops suddenly as shown by D4 with the change of the deceleration of the vehicle accompanying it, and it causes temporary ripple of braking force with the response delay of actual hydraulic brake torque behind the command of hydraulic brake torque raised to assist the drop. Therefore, this controller stores the deceleration of the vehicle at the instant t1 in advance, and gets the second critical regenerative braking torque Tmlmt(b) as shown by D3, using the stored value of the deceleration of the vehicle on and after the instant t2, and sets it to the regenerative torque limiting value Tmfin. COPYRIGHT: (C)2006,JPO&NCIPI

Regenerative braking system for hybrid electric vehicle

Abstract: A regenerative braking system for a hybrid electric vehicle 10 comprises an engine 14, a geared electric motor-generator or transaxle assembly 16 and a transmission assembly 18 which selectively receives torque from the engine 14 and the motor-generator assembly 16, and which delivers an output torque to a pair of road wheels 26,28. The engine 14 is connected to the transmission 18 by a clutch 20, which the system disconnects during certain braking events. This allows a maximum amount of energy to be recovered by eliminating engine drag. The motor-generator assembly 16 simulates engine drag, thus providing a driver of the vehicle 10 with a consistent feel during all operating modes. The powertrain configuration is typically a parallel hybrid front wheel drive system. The braking system interfaces with a friction brake system and preferably responds to inputs such as an accelerator pedal position, vehicle speed and battery 34 charge level.

Electro mechanical brake, control device and control methods

Abstract: When a vehicle is suddenly stopped by turning off an ignition key switch on a way of a slope road, a braking force maintaining control is not preformed, and it often occurs that the vehicle moves down along the slope road. To prevent such occurrence, an electro-mechanical braking device for maintaining the braking force is provided so that the vehicle is parked securely. The electro-mechanical braking device includes a parking brake mechanism for maintaining the brake force even when an ignition key switch (power supply switch) of the vehicle is turned off. When the power supply switch (ignition key switch) of the vehicle is turned off with a braking pedal being stroked or a braking operation signal being present, the parking-brake mechanism is activated (the brake force is maintained).

Device for inrush current prevention and dynamic braking in a motor

Abstract: A device for inrush current prevention and dynamic braking in a motor having a plurality of power inputting terminals, comprises a diode rectifying unit rectifying power supplied from an AC power supplying unit; a capacitor smoothing the power rectified by the diode rectifying unit; a resistor disposed between the AC power supplying unit and the capacitor, being connected to the capacitor; an inverter connected to terminals of the capacitor and the power inputting terminals of the motor, inverting the power from the capacitor into an AC power having multiple phases and supplying the AC power having multiple phases to the motor; a dynamic braking circuit short-circuiting the power input terminals of the motor; and a relaying unit including a first node connecting the dynamic braking circuit to the resistor and a second node connecting the diode rectifying unit to the capacitor in parallel.

System for control and deceleration of elevator during emergency braking

Abstract: A system for controlling the braking of an elevator car during an emergency. When there is a power failure or other emergency, a brake is applied to slow the elevator car to a stop in a controlled fashion. By Controlling the braking, the car is stopped in a short time but without discomfort to the passengers. The controller receives inputs from the rope movement, motor movement, temperature and the braking current to correctly determine the amount of braking which should be applied.

Multi-layer fuzzy controller for control of power networks

Abstract: In this paper, a multilayer fuzzy logic controller (MLFC) is proposed for the stability enhancement of the electric power system making use of a dynamic braking strategy. The proposed controller has two layers. The first layer, termed the supervisory layer, specifies the region of operation of the subcontrollers (SCs) within the second layer, called the execution layer. The outputs of the SCs are then fuzzily combined to achieve the overall objective of the system. The MLFC was found to be very "robust"-insensitive to changes in the network configuration. The scheme was tested on a nine-bus system with three generators and three loads and also on the IEEE four-generator test system. A comparison with a two-level hierarchical controller was made to show the effectiveness of the proposed method. The simulation results obtained support the concept of the multilayer fuzzy-logic-based braking resistor control scheme and that it is also a valuable tool for short-term and long-term stability crisis management.

An application of sliding mode control to vehicle steering in a split-mu maneuver

Abstract: In this paper a sliding mode integral action controller and sliding mode observer are used to enhance vehicle stability in a split-/spl mu/ maneuver. Anti-lock braking systems (ABS) have become an integral part of modern cars, and they have dramatically improved vehicle handling in braking manoeuvers. However, when a vehicle attempts to brake on a surface with uneven friction coefficient, such as on wet or icy roads, a so-called split-/spl mu/ scenario, the yaw moment generated by the asymmetric braking can prove demanding for an inexperienced driver. The controller presented here works in conjunction with a conventional ABS system to provide safe and effective braking through steer-by-wire. This paper extends previous state-feedback work by only using certain measurable quantities in the controller, estimating further signals by employing an observer.

Method and apparatus for power management of a braking system

Abstract: A vehicle braking system and method of control is disclosed which includes electromagnetic and friction braking functionality. The electromagnetic braking system includes a generator which supplies power to eddy current devices. Accordingly, the eddy current devices apply a retarding torque on the wheels of the vehicle. In the event the generator is unable to supply a predetermined amount of power to eddy current devices, friction braking is activated thereby enhancing braking performance.