A HYDRO KINETIC TORQUE BASED Regenerative Braking
Power Generation System called "Gravio"
Kinetic Energy Regenerative Braking is not new. It is used in F1 cars, electric cars, trains and trams as a slowing / stopping mechanism. Kinetic is scalar but direct it and use the work energy principle and you have a different dynamic. There is a train in Sweden that uses this process at a constant velocity to generate electricity - see below. Gravio uses this same constant velocity concept, in a unique patented way. It has never been done this way before. The whole process is patented.
In 1886 by the Sprague Electric Railway & Motor Company, founded by Frank J. Sprague, introduced two important inventions: a constant-speed, non-sparking motor with fixed brushes, and regenerative braking. Constant-speed/velocity is the operative word in our application.
During braking, the traction motor connections are altered to turn them into electrical generators. The motor fields are connected across the main traction generator (MG) and the motor armatures are connected across the load. The MG now excites the motor fields. The rolling locomotive or multiple unit wheels turn the motor armatures, and the motors act as generators, either sending the generated current through onboard resistors (dynamic braking) or back into the supply line (regenerative braking). Compared to elector-pneumatic friction brakes, braking with the traction motors can be regulated faster improving the performance of wheel slide protection.
For a given direction of travel, current flow through the motor armatures during braking will be opposite to that during motoring. Therefore, the motor exerts torque in a direction that is opposite from the rolling direction. Braking effort is proportional to the product of the magnetic strength of the field winding's, multiplied by that of the armature winding's.
Electricity generated by regenerative braking may be fed back into the traction power supply; either offset against other electrical demand on the network at that instant, used for head end power loads, or stored in line-side storage systems for later use.
(ALKAB in Sweden, who has an iron ore mine in Kiruna, has perfected this process in their IORE Locomotive and hence trains. LKAB's iron ore are transported on the 536km long Ore Railway and Ofoten Railway from Kiruna mine to the Ports of Narvik in the north-west to Port of Luleå in the south-east. The Ore Railway section links the mine operations to Ofoten Railway on its way to the ports. The Ore railway starts at the mine some 513m in elevation. There is a gentle almost constant slope (0.73degrees) down to the ports of approximately 42km from the mine to the Ofoten rail lines. LKAB has 17 IORE locomotives in operation, using the Ore Railway all year round. The trains hauled by IORE have 68 cars, are 750 meters (2,460 ft) long and weigh 8,600 tonnes (8,500 long tons; 9,500 short tons). The full ore trains operate at constant 60 kilometers per hour (37 mph), while the empty return trains operate at 70 kilometers per hour (43 mph). The downward trajectory velocity is controlled via a regenerative braking process at 60kmph and therefore there is a constant kinetic energy flow on the wheels.
The IORE locomotive is the world's strongest locomotive, with a traction of 1,200 kilo-newtons and with thanks to the locomotive's asynchronous generators, the momentum force is converted into electricity when the trains perform generator regenerative braking. This braking allows the train to travel down the slope at a constant safe speed (notice the slope, the constant speed and frequency of trains in the video) whilst generating electricity all the way down. The regenerative braking system is constantly fighting the forces of gravity on the train, and therefore it can be viewed as a "gravity" power generation system. Due to the continuous flow of train loading at the mine, there is therefore a continuous flow of trains traveling down the gentle slope and as a result electrical energy is being constantly generated into the network. Quote: “The rail cars are full of thousands of tons of iron ore on the way down to Narvik, and these trains generate large amounts of electricity by regenerative braking, with a maximum recuperative braking force of 750 kN. From Riksgränsen on the national border to the Port of Narvik, the trains use only a fifth of the power they regenerate. The regenerated energy is sufficient to power the empty trains back up to the national border. Any excess energy from the railway is pumped into the power grid to supply homes and businesses in the region, and the railway is a net generator of electricity”.
We have taken the same principle and applied by the train and electric cars + F1 cars to slow them down and applied it to our hydro kinetic torque based regenerative braking system adding some unique features to get it to work. The process is not new but its application in hydro is new and it works very well and it produces much more power than standard hydro systems in the multiples. This brings about many wonderful opportunities and is a game changer.
LKAB has taken Sprague's invention and uses it well to their advantage. Well done!