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The direct torque method performs very well even without speed sensors. However, the flux estimation is usually based on the integration of the motor phase voltages. Due to the inevitable errors in the voltage measurement and stator resistance estimate the integrals tend to become erroneous at low speed. Thus it is not possible to control the ...
Rotor losses are minimal compared to those of an induction motor, however it normally has less torque. [2] [3] Once started at synchronous speed, the motor can operate with sinusoidal voltage. Speed control requires a variable-frequency drive. High-powered SynRMs typically require rare-earth elements such as neodymium and dysprosium. However, a ...
The simplest SRM has the lowest construction cost of any electric motor. Industrial motors may have some cost reduction due to the lack of rotor windings or permanent magnets. Common uses include applications where the rotor must remain stationary for long periods, and in potentially explosive environments such as mining, because no commutation ...
Earlier submarines carried four high-speed electric motors (two per shaft), which had to be fitted with reduction gears to slow their outputs down to an appropriate speed for the shafts. This reduction gearing was very noisy, and made the submarine easier to detect with hydrophones .
Exhaust brakes are simpler in operation than an engine brake.Essentially, the exhaust pipe of the vehicle is restricted by a valve.This raises the pressure in the exhaust system, forcing the engine to work harder on the exhaust stroke of its cylinders, so again the engine is acting as an air compressor, with the power required to compress the air being withheld from the exhaust pipe, retarding ...
The 2011 Nissan Leaf was the first electric car equipped with Nissan's Vehicle Sound for Pedestrians called 'Canto'.. Electric vehicle warning sounds are sounds designed to alert pedestrians to the presence of electric drive vehicles such as hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and battery electric vehicles (BEVs) travelling at low speeds.
When used with a load that has a torque curve that increases with speed, the motor operates at the speed where the torque developed by the motor is equal to the load torque. Reducing the load causes the motor to speed up, while increasing the load causes the motor to slow down until the load and motor torque are again equal.
In electric and hybrid vehicles, electric motors provide the drivetrain resistance, recharging the onboard battery using energy recovered from the vehicle's kinetic motion which would otherwise have been wasted. In hybrid vehicles, the engine runs on electric power to dissipate excess energy when the battery has been fully recharged.