1. A stop lamp lighting control device for an electric Vehicle having an electric regenerative braking system, comprising:
a calculation unit that converts a previously-defined first deceleration threshold value for turning on a stop lamp or a previously-defined second deceleration threshold value for turning off the stop lamp to a first regenerative torque threshold value for turning-on the stop lamp or a second regenerative torque threshold value for turning-off the stop lamp at each vehicle speed by calculation assumed that a weight of the electric vehicle is a curb weight or a gross vehicle weight; and
a determination unit that performs a comparison between a regenerative torque value generated by the electric regenerative braking system during a regenerative braking and the first regenerative torque threshold value or the second regenerative torque threshold value at each vehicle speed and controls the stop lamp to be turned on or turned off based on the comparison result.
2. The stop lamp lighting control device according to claim 1, wherein the calculation unit includes:
a first calculation unit that converts the first deceleration threshold value to the first regenerative torque threshold value at each vehicle speed by calculation assumed that the weight of the electric vehicle is the curb weight; and
a second calculation unit that converts the second deceleration threshold value to the second regenerative torque threshold value at each vehicle speed by calculation assumed that the weight of the electric vehicle is the gross vehicle weight,
wherein the determination unit controls the stop lamp to be turned on when the regenerative torque value is larger than the first regenerative torque threshold value, and
wherein the determination unit controls the stop lamp to be turned off when the regenerative torque value is equal to or smaller than the stop lamp turn-off regenerative torque threshold value.
3. The stop lamp lighting control device for an electric vehicle according to claim 1, wherein the determination unit is configured:
to keep the stop lamp turned on when the regenerative torque value is changed to he equal to or smaller than the first regenerative torque threshold value while the stop lamp is at a turned on state; and
to keep the stop lamp turned off when the regenerative torque value is changed to exceed the second regenerative torque threshold value while the stop lamp is at a turned off state.
4. The stop lamp lighting control device for an electric vehicle according to claim 2, wherein the determination unit is configured:
to keep the stop lamp turned on when the regenerative torque value is changed to be equal to or smaller than the first regenerative torque threshold value while the stop lamp is at a turned on state; and
to keep the stop lamp turned off when the regenerative torque value is changed to exceed the second regenerative torque threshold value while the stop lamp is at a turned off state.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A rotatable drive mechanism for driving an electrical generator, which mechanism provides a substantially constant speed rotational output for driving the generator from a variable speed rotatable input, the mechanism including a variable speed input, geared differential transmission for receiving power from the variable speed input, the differential transmission having two power sharing paths, a first of the paths in rotational communication with an output for driving the generator and a second of the paths in rotational communication with an electric machine operable to provide a variable reaction torque in the second path, the mechanism including a torque monitor for monitoring dynamic torque at the input and a controller for altering the reaction torque in the second path in response to changes in the monitored torque, by means of operating the electric machine as a motor or a generator, and thereby permitting the substantially constant speed rotation of the output, characterised in that the monitor monitors the dynamic torque at the input and the controller operates the electric machine to negate at least some of the inertia of the electric machine andor of the second of the paths.
2. A rotatable drive mechanism as claimed in claim 1 wherein the input includes a shaft and a step-up gearbox for increasing the rotational speed delivered to the geared transmission.
3. A rotatable drive mechanism as claimed in claim 2 wherein said dynamic torque monitor monitors the substantially stationary reaction torque of the step-up gearbox.
4. A rotatable drive mechanism as claimed in claim 1 wherein said differential transmission comprises a planetary gear arrangement having a planet gear carrier for being driven by the input, a sun wheel which forms part of the first power path and a ring gear which forms part of the second power path.
5. A rotatable drive mechanism as claimed in claim 1 wherein, when the input speed is below a predetermined value the electric machine is operable as a motor and provides a variable reaction torque in the second path such that a driving torque is provided to the gear transmission via the second power path and in so doing maintains the rotational speed of the first power path substantially at a predetermined speed.
6. A rotatable drive mechanism as claimed in claim 1 wherein, when the input speed is above the predetermined value the electric machine operable as a generator and provides a further variable reaction torque and accepts power from the gear transmission via the second power path and in so doing maintains the rotational speed of the first power path substantially at the predetermined speed.
7. A rotatable drive mechanism as claimed in claim 1 wherein the second power path includes a further gearing for changing the rotational speed of the second power path.
8. A rotatable drive mechanism as claimed in claim 1 wherein the first or second power path includes a clutch or brake for disengaging or braking the respective path when rotation of the is rotor is inhibited but the generator is still in motion.
9. A rotatable drive mechanism as claimed in claim 1 wherein the electric machine is a switched reluctance machine (SRM).
10. A rotatable drive mechanism as claimed in claim 9 wherein, the angular position of the SRM is used, in part, to control the reaction torque.
11. A method of controlling the rotational speed of a generator drive mechanism to provide a substantially constant rotational speed for the generator resulting from a variable speed input, the method employing a mechanism which provides a substantially constant speed rotational output for driving the generator from a variable torque rotatable input, the mechanism including a variable speed input, geared differential transmission for receiving power from the variable torque input, the differential transmission having two power sharing paths, a first of the paths in rotational communication with an output for driving the generator and a second of the paths in rotational communication with an electric machine operable to provide a variable reaction torque in the second path, the method including the following steps, to be performed in any suitable order, of: a) monitoring the dynamic torque of the input; b) controlling the reaction torque in the second path in response to the monitored dynamic input torque, by means of operating the electric machine as a motor or a generator, and thereby permitting the substantially constant speed rotation of the output; and the method being characterised by the step of: c) operating the electric machine to substantially negate the effects of inertia in the second path andor in the electric machine.
12. A method as claimed in claim 11 wherein the monitored dynamic input torque is the reaction torque of the geared differential transmission.
13. A method as claimed in claim 11 including the further steps of: d) in addition to step a), measuring the input speed and generator load; and e) controlling the reaction torque in the second path in response to the input speed and generator load, as well as in response to the monitored input torque, by means of operating the electric machine as a motor or a generator.
14. A method as claimed in claim 13 including the further steps of: f) operating the electric machine as a motor, at a first predetermined input speed range; and g) operating the electric machine as a generator at a second predetermined input speed range which second range is higher than the first range.
15. A rotatable drive mechanism for driving an electrical generator, which mechanism provides a substantially constant speed rotational output for driving the generator from a variable speed rotatable input, the mechanism including a variable speed input, geared differential transmission for receiving power from the variable speed input, the differential transmission having two power sharing paths, a first of the paths in rotational communication with an output for driving the generator and a second of the paths in rotational communication with an electric machine operable to provide a variable reaction torque in the second path, the mechanism including a torque monitor for monitoring dynamic torque at the input and a controller for altering the reaction torque in the second path in response to changes in the monitored torque, by means of operating the electric machine as a motor or a generator, and thereby permitting the substantially constant speed rotation of the output, characterised in that the dynamic input torque is monitored by means of measuring the stationary reaction torque of the geared differential transmission.
16. A wind or water driven turbine, having a rotatable drive mechanism as claimed in claim 1.
17. A wind or water driven turbine including a variable speed wind or water drivable rotor, a generator, and a differential gearbox providing rotary communication between the rotor and the generator, the generator being drivable, via the gearbox, at substantially constant speed by the variable speed rotor, the gearbox providing a variable torque reacting against the rotor torque for allowing said substantially constant generator speed and for allowing said rotor to increase or decrease in speed with increased or decreased wind or water speed characterised in that the dynamic input torque applied to the gearbox by the rotor at a reaction point of the gearbox is measured to provide said variable torque reacting against the rotor.
18. A wind or water turbine as claimed in claim 17 wherein the variable reaction torque is providable by a further generator having further rotary communication with the gearbox, the further generator being operable as a further generator or as a motor, and being further operable to substantially negate its own inertia andor the inertia of said further rotary communication.
19. A wind or water turbine as claimed in claim 18 wherein the further generator is a switched reluctance machine.
20. A wind or water driven turbine, having a drive mechanism operable according to the method of claim 11.