Description:FIELD OF INVENTION
The present invention relates to the field of hydropower generation and pumped storage technology, and more particularly to a gravity-assisted spiral track system that can function both as a torque booster for Kaplan/Francis turbines and as a standalone pumped storage mechanism.

BACKGROUND OF THE INVENTION
Conventional hydropower systems rely on turbine efficiency, typically between 85–90%, but significant kinetic energy is lost in draft tube water outflow. Pumped storage systems are well known but often require large infrastructure and high capital investment. Torque boosters and secondary recovery mechanisms remain limited in prior art due to shock loads, inefficiencies, and poor integration.
The present invention addresses these challenges by providing a modular spiral track with descending water tanks that add torque to a vertical shaft, either supplementing turbine output or driving pumps for head recovery. The addition of regenerative braking and anti-jerk engagement mechanisms overcomes technical limitations of prior designs, enabling smooth operation, energy recovery, and retrofit feasibility.

STATEMENT OF INVENTION
The invention provides a spiral track-based gravity-assisted hydropower system in which water-filled tanks descend under gravity to impart torque to a vertical shaft. The system is configurable in two modes: (i) a retrofit mode, wherein supplementary torque is provided to the drive shaft of an existing Francis or Kaplan turbine, and (ii) a standalone mode, wherein the shaft drives a pumping system for water head recovery in pumped storage plants. The system further includes a regenerative braking unit for recovering energy from decelerating tanks and reusing it for auxiliary operations, and an anti-jerk engagement mechanism incorporating a pre-spin arrangement and damping elements to ensure smooth torque transfer without vibration.

OBJECTS OF THE INVENTION
1. To provide a gravity-assisted spiral track hydropower system that can be used both as a retrofit torque booster for existing Kaplan/Francis turbines and as a standalone pumped storage unit.
2. To utilize draft tube water energy and gravitational descent of tanks for generating additional torque without modifying the primary turbine runner.
3. To incorporate a regenerative braking mechanism that recovers energy during deceleration of tanks and reuses it for resetting and pre-spin operations.
4. To design an anti-jerk engagement arrangement (including pre-spin motor, clutch, damper, and ratchet) that eliminates shock loads and vibration during tank-to-shaft engagement.
5. To ensure scalable modular design, enabling multiple tanks to provide continuous torque for higher power output.
6. To provide a system that is low-maintenance, cost-effective, and feasible for both new and existing hydropower plants.

DETAILED PARTS DESCRIPTION OF INVENTION
Figure 1A illustrates a cross-sectional front view of the proposed gravity-assisted spiral tank hydropower system, highlighting its major components and their functional interconnection.
1. Retrofit Drive Shaft (1): The shaft is configured to receive supplemental torque from the spiral tank system and transmit it to the existing turbine-generator assembly. In retrofit mode, this shaft is mechanically coupled to the Kaplan/Francis turbine output shaft.
2. Draft Tube Guide Vane (2): Located below the primary turbine draft tube, the guide vane directs the residual water flow towards the water reservoir.
3. Torque Transmission Gearbox (3): A multi-stage gearbox couples the spiral shaft (15) with the turbine shaft, ensuring suitable speed and torque conversion. The gearbox also allows bidirectional operation when configured for pumped storage applications.
4. Overhead Water Reservoir (4): Positioned above the spiral track, the reservoir stores incoming draft tube water and supplies it to the tanks (9) after filtration via gravity. This ensures a steady and regulated filling process.
5. Inlet Wire-Mesh Strainer (5): A filtration unit placed at the reservoir inlet prevents debris, silt, and foreign particles from entering the tank system, thereby reducing wear and maintenance.
6. Conical Supply Water Tube (6): A funnel-shaped conduit directs water from the reservoir (4) into the tanks (9) at the filling station. Its conical shape ensures smooth water velocity distribution, minimizing turbulence.
7. Flow Control Valve 1 (7): A regulating valve provided along the supply line controls the flow rate of water into each tank, thereby managing load distribution and synchronization.
8. Fluid/Arpex Flexible Coupling (8): A torsionally flexible coupling is placed between the spiral shaft (15) and gearbox (3) to absorb minor misalignments, vibrations, and shocks during torque transmission.
9. Gravity-Descent Water Tank (9): Multiple tanks are mounted radially around the spiral shaft, each capable of filling, descending under gravity, emptying through valve (Flow control valve 2), and resetting. The tanks act as the primary torque-generating elements.
10. Auxiliary Shaft Disengagement Guide (10): This arrangement allows the shaft slider assembly (14) connected to each tank to move away from the main vertical shaft (15) after disengagement. Electrically operated rollers (102) using motor (101) slide the sliding auxiliary shaft towards the Tank Reset System (17). It ensures that once a tank has completed its torque contribution cycle, its auxiliary shaft is guided laterally out of contact with the main shaft, preventing drag or unwanted resistance during the return/reset cycle.
11. Tank-Specific Regenerative Braking System (11): A separate regenerative braking unit is mounted at the bottom end of each tank’s descent path. This system provides controlled deceleration of the tank at the end of its downward journey. The braking energy is recovered and stored in an electrical accumulator or DC bus, and the recovered power is reused, supplying torque to initiate the tank movement on spiral ramp and to operate other electrical system like sliding shaft roller, flow control valves, etc. This configuration ensures smooth initiation or stopping of each tank and avoids shock loads on the shaft.
• Wheel (111): Rolling element designed to move along the spiral ramp or spiral rail track, enabling guided vertical or horizontal motion.
• DC Motor (112): Direct current motor capable of operating in both motoring and generating modes, ensuring bidirectional energy conversion.
12. Spiral Ramp/ Rail Track (12): A helical or spiral ramp structure and main shaft (15) guides the tanks from top to bottom while simultaneously imparting torque to the shaft (15). Spiral ramp can be used for tank with wheel arrangement and Spiral rail track can be used
13. Anti-Jerk Shaft Engagement Assembly (13): This assembly comprises a pre-spin motor, electromagnetic clutch, torsional damper, and ratchet mechanism. It ensures that each tank smoothly engages with the rotating shaft (15) without introducing sudden shocks or vibrations.
• Robotic Arm (131): Actuating arm providing controlled engagement and disengagement in the anti-jerk mechanism.
• Caliper Brake Pad (132): Friction element applied to absorb shocks and stabilize sudden load variations.
• Grooves under Robotic Arm (133): Guide slots enhancing grip and precision for robotic arm movement.
• Robotic Arm with Integrated Dog Clutch Teeth (134): Modified arm incorporating dog clutch engagement features for shock-free operation.
• Spring / Electromagnetic Clutch (135): Energy storage or electromagnetic actuation unit for smooth torque transmission.
• Dog Clutch Assembly (136): Interlocking mechanism transmitting torque while preventing sudden jerks during engagement.
• Ratchet System (137): Unidirectional locking device ensuring controlled motion and avoiding reverse slip under load.
• Pre-spin DC motor (138): The pre-spin motor is a small auxiliary motor that prepares the auxiliary shaft (connected to a tank) before it locks onto the main vertical shaft. Its role is to synchronize rotational speed and avoid a sudden torque shock (jerk) when the tank engages with the shaft.
14. Shaft Slider Assembly (14): A secondary shaft element that connects each tank to the main shaft via the anti-jerk engagement system. It allows vertical and angular adjustment during engagement/disengagement.
15. Central Vertical Main Shaft (15): The principal power shaft aligned with the spiral ramp, receiving continuous torque contributions from multiple descending tanks. The shaft transmits net torque to the gearbox (3).
16. Vertical Sliding Guide Channel (16): A structural guide ensuring alignment and smooth vertical movement of tanks and auxiliary shafts during reset and engagement processes.
17. Motorized Tank Reset/Vertical Tank Lifting System (17): A powered hoist/winch assembly designed to lift empty tanks from the bottom of the spiral back to the top filling station. The reset mechanism is powered partially or fully by recovered regenerative braking energy.
18. Bottom Shaft Support Bearing (18): A heavy-duty bearing assembly located at the foundation level to support the main vertical shaft (15), ensuring stable rotation under variable load conditions.
19. Tank Outlet Port (19): Outlet passage from main tank, enabling controlled water discharge into counterweight tank for lifting operation.
20. Flow Control Valve 2 (20): Regulates water flow from main tank outlet to counterweight tank, ensuring precise transfer and controlled lifting sequence.
21. Counterweight Tank (21): Auxiliary tank receiving water to create counterbalancing force, enabling upward movement of empty main tank efficiently.
22. Braking System (22): Electrically operated safety mechanism to hold or release tank and counterweight motion, ensuring controlled stopping and positioning during lifting.
23. Base Frame/Platform (23): Structural support frame providing stable base for tank placement, lifting system, and pulley arrangement during operation.
24. Drum-Pulley (24): Combined drum and pulley mounted on a common shaft; the large-diameter drum guides rope movement of the base frame, while the smaller pulley directs rope displacement of the counterweight.
25. Base Frame Pulley (25): Smaller pulley mounted on base frame to redirect rope path and enhance vertical motion translation efficiency.
26. Flow Control Valve 3 (26): Valve controlling final discharge of water from counterweight tank to drain pipe and river outlet.
27. Drain Pipe (27): Pipe pathway directing released water safely from counterweight tank to river, completing hydraulic lifting cycle.
28. Generator (28): Existing generator system
29. Fluid Coupling (29): Fluid coupling between generator and turbine.
30. Sliding Channel (30): use to guide the base frame vertical upward and downward motion

DETAILED WORKING DESCRIPTION OF THE INVENTION
Modes of Operation
1. Retrofit Torque Booster Mode: The shaft (15) couples through a gearbox (3) to the turbine shaft of an existing Kaplan/Francis turbine, providing additional torque from tank descent. This allows higher generator loading without increasing water flow.
2. Standalone Pumped Storage Mode: The shaft (15) is coupled to a pump, enabling lifted water to be stored at higher elevation reservoirs. Here, gravitational torque from descending tanks directly assists the pumping cycle.

 Retrofit Structure of Gravity Assisted Torque Booster System
General Operation- [Ref: Figure 1A]
1. Water Intake and Guidance
o Water exiting the draft tube is directed through the Guide Vane (2) into the Reservoir (4).
o A Mesh Filter (5) removes debris and suspended solids.
o The filtered water is channeled by the Conical Tube (6) into the Tanks (9).
2. Tank Descent and Torque Generation
o Once filled, the tanks descend along the Spiral Ramp (12), mounted on motorized wheels of the Regenerative Braking System (11).
o During descent, each tank imparts torque to the Vertical Main Shaft (15) through the Auxiliary Shaft (14) and the Anti-Jerk Engagement System (13).
3. Power Transmission
o The generated torque is transmitted via a Fluid Coupling (8) and Gearbox (3).
o In retrofit mode, torque is transferred to the turbine shaft, whereas in standalone mode, it drives the pump directly.
4. Tank Deceleration and Reset
o At the lower end of the spiral ramp, the Regenerative Braking System (11) decelerates the tanks smoothly.
o Tanks are emptied, reducing excess load, and then returned to the upper level by the Tank Lifting System (17) for the next cycle.
5. Shaft Stability
o The Bottom Shaft Bearing (18) provides lateral stability to the vertical main shaft, ensuring continuous and vibration-free operation.

 Retrofit Structure of Gravity Assisted Standalone Pump Storage System
General Operation- [Ref: Figure 1B]
In the standalone pumped storage configuration, the operational principle remains similar to that described for the retrofit torque booster mode in Figure 1A. However, instead of transmitting torque to a generator, the main vertical shaft is directly coupled to a solid ground fixture at its upper end through a heavy-duty bearing support. This fixed arrangement converts the descending torque of the water-filled tanks into rotational energy that is transmitted to a pumping unit. The pump thereby re-establishes hydraulic head by returning water from the lower reservoir to the upper reservoir.
The absence of a generator in this configuration simplifies the transmission layout, while the ground-coupled bearing ensures structural stability during prolonged torque application. This arrangement enables the system to function as a dedicated gravity-assisted standalone pumped storage module, offering an energy recovery and storage solution independent of turbine-generator shafts.

Figure 2A – Top View of Section A
Figure 2A shows the arrangement of the central vertical shaft and auxiliary components inside the Water Reservoir (4).
• The Retrofit Drive Shaft (1) is concentrically positioned at the center.
• Surrounding it, the Draft Water Guide Vane (2) channels draft-tube water toward auxiliary subsystems.
• A Gearbox (3) is mounted radially to the drive shaft for torque transfer.
• The Water Reservoir (4) acts as the structural enclosure.
• A Mesh Filter (5) prevents debris entry.
• Downstream, a Conical Water Tube (6) guides filtered water, maintaining laminar flow toward tanks for efficient filling.
This configuration ensures clean water supply, controlled flow, and effective integration of torque transfer through the gearbox.

Figure 2B – Top View of Section B
Figure 2B details the descent of the Water Tank (9) along the Spiral Ramp (12) and its torque transfer to the Main Shaft (15).
• Each filled Water Tank (9) is supplied through a Flow Control Valve (7).
• The Sliding Auxiliary Shaft (14) connects the tank to the main shaft, while the Auxiliary Shaft Disengagement Guide (10) ensures smooth engagement/disengagement.
• As the tank descends the spiral ramp, gravitational potential energy is converted into torque, transmitted to the shaft through the Engagement System (13).
• Section C shows tanks at full momentum, delivering maximum torque to the shaft.
• Section D depicts regenerative braking action, decelerating tanks before disengagement, ensuring smooth operation.
• After reaching the bottom, safe disengagement of tanks begin controlled emptying to minimize residual load.
This sequence highlights the coordinated cycle of filling, torque transfer, braking, and resetting, enabling continuous energy extraction from the water flow.

 Regenerative Braking System (11)-
General operation- [Ref of Figure 4]
1. Tank Descent and Energy Capture:
o As the tank reaches the lower end of its descent path, a dedicated regenerative braking unit engages.
o The braking system provides controlled deceleration, preventing sudden impact or shock loading on the shaft.
2. Energy Recovery Process:
o During deceleration, the system operates in generating mode.
o The kinetic energy of the moving tank is converted into electrical energy through the DC Motor (112) acting as a generator.
o The generated energy is directed to an electrical accumulator or DC bus for storage.
3. Reuse of Recovered Energy:
o The stored electrical energy is subsequently reused in motoring mode to:
 Provide startup torque to initiate the tank’s movement along the spiral ramp through the Wheel (111) connected to a DC Motor (112).
4. Bidirectional Motor Functionality:
o The DC Motor (112) alternates between generating mode (energy recovery during braking) and motoring mode (torque supply during acceleration).
o This dual functionality ensures efficient power utilization and reduces external energy demand.
5. Smooth Operation:
o The regenerative braking system ensures gradual deceleration, minimizing mechanical stress.
o It also enables smooth re-acceleration of tanks, reducing jerk loads and extending the lifespan of the shaft and connected mechanisms.

 Auxiliary Shaft Disengagement Guide (10)
General operation- Auxiliary Shaft Disengagement Guide [Ref of Figure 4]
1. Completion of Torque Contribution:
o After the tank has completed its torque transfer cycle through the auxiliary shaft (14), the engagement system disengages from the main vertical shaft (15).
2. Initiation of Disengagement Movement:
o An electrically operated roller assembly (102), driven by a dedicated motor (101), is activated to initiate lateral movement of the auxiliary shaft (14).
3. Guided Retraction:
o The rollers smoothly slide the shaft slider assembly away from the main vertical shaft along a predefined lateral channel.
o This ensures controlled and precise separation, avoiding mechanical shocks or misalignment.
4. Clearance for Reset:
o Once fully retracted, the auxiliary shaft is completely out of contact with the main vertical shaft, thereby preventing drag, frictional resistance, or parasitic torque during the reset cycle.
5. Transfer to Reset System:
o The disengaged auxiliary shaft (14) is guided toward the Tank Reset System (17) for repositioning.
o This allows the tank to prepare for its next operational cycle without interfering with ongoing torque transfer by other tanks.
6. Operational Continuity:
o By ensuring quick and friction-free disengagement, the system maintains continuous plant operation, improves efficiency, and reduces wear on both shafts.

 Anti-Jerk Engagement Assembly (13)-
General operation- Dog clutch type [Ref of Figure 3A]
1. Pre-Spin Synchronization:
o Before engagement, a pre-spin DC motor (operating in motoring mode) accelerates the auxiliary shaft to match the main shaft’s RPM.
o Encoder feedback ensures precise synchronization to prevent relative speed mismatch.
2. Soft Clutch Engagement:
o An electromagnetic or spring-based clutch initiates gradual torque transfer between shafts.
o This smooth transition reduces impact loading during initial contact.
3. Positive Locking with Dog Clutch:
o Once speed and torque are synchronized, the dog clutch engages to provide a rigid, positive mechanical lock.
o This ensures reliable torque transmission under full load conditions.
4. Oscillation Absorption:
o A torsional damper at the gearbox interface absorbs residual vibrations or torque spikes, maintaining smooth power flow.
5. One-Way Torque Control:
o A ratchet system prevents reverse motion, ensuring torque is only transmitted in the intended direction.
6. Energy Recovery:
o Regenerative braking energy from deceleration phases is partly reused to power the pre-spin motor, making the system energy-efficient and self-sustaining.

General operation– Robotic Helical Grip with Caliper Brakes [Ref of Figure 3B]
1. Initial Alignment:
o The sliding auxiliary shaft (14) approaches the vertical main shaft (15), which is machined with a helical groove or Archimedes-screw profile.
o A robotic actuator aligns complementary grooves of the grip with the shaft groove.
2. Controlled Insertion:
o Hydraulic or servo actuators drive the grip into the shaft’s helical profile.
o A tapered lead-in surface on the grooves ensures smooth entry and minimizes impact.
3. Caliper Braking and Synchronization:
o Caliper brakes with friction pads clamp onto the helical groove to provide initial braking and controlled synchronization of rotational speeds.
o This step avoids shock loading before full engagement.
4. Full Torque Transfer:
o Once engaged, the robotic helical grip locks firmly into the shaft groove.
o The grip transmits torque effectively, while a torsional damper mitigates any residual oscillations.
5. Load Sharing and Safety:
o Multiple circumferential grip modules can be deployed around the shaft, sharing torque loads and providing redundancy for safe operation.
6. Disengagement:
o At release, calipers unclamp and the robotic grip retracts.
o The auxiliary shaft (14) is then guided back along its sliding channel (16), clearing the shaft for the next operation.

 Tank Lifting/Reset System (17)
General Operation- [Ref of figure 6]
• Starting Position
o The tank (9) is empty and rests at the bottom on the base frame (23).
o The counterweight tank (21) is positioned at their top.
o The brake (22) holds the system securely in place.
• Initiating Water Transfer
o Opening valve (20) allows water to flow from the tank (9) to the counterweight tank (21) via the tank outlet port (19).
o This transfer increases the counterweight tank’s effective weight to approximately three times that of the emptied tank.
• Tank Ascends, Counterweight Descends
o Releasing brake (22) enables the tank (9) to rise along the base frame while the counterweight tank (21) moves downward.
o The drum-pulley (24) and small pulley (25) system, amplifies the vertical displacement of the tank relative to the counterweight, allowing significant upward movement with minimal counterweight travel.
• Holding at Upper Position
o Once the tank reaches the desired height, the brake engages to hold it in place.
o The tank moves on their wheel and then positioned for refilling, while the counterweight remains at the lower position.
o The PLC opens the drain valve (26), allowing water to be discharged into the river.
• Lowering (Full Tank)
o Releasing the brake allows the base frame to descend automatically as the counterweight is reduced.
o The system is now ready to lift the next empty tank.

PLC-Based Operation and Control
The operation of the gravity-assisted hydropower system is governed by a PLC-based control unit, which ensures precise sequencing, safe engagement, and efficient energy use. The PLC continuously monitors sensor inputs (tank position, shaft RPM, water level, and valve states) and coordinates the following functions:
1. Tank Filling and Emptying
o Controls opening and closing of flow control valves for accurate tank filling at the top and progressive emptying along the spiral track.
o Prevents overflow or premature emptying through feedback-based valve actuation.
2. Tank Lifting and Counterweight Reset
o Automates valve operation for hydraulic water transfer between the main tank and counterweight tank, initiating passive lifting.
o Monitors counterweight displacement and synchronize brake release for smooth upward reset of empty tanks.
3. Anti-Jerk Engagement
o Controls pre-spin motor activation, clutch engagement, and ratchet locking sequence.
o Matches auxiliary shaft RPM with main shaft before positive locking, thereby preventing mechanical shock.
4. Regenerative Braking Utilization
o Allocates recovered braking energy to wireless operations including valve actuation, auxiliary shaft movement, and pre-spin motor operation.
o Ensures self-sustained auxiliary power without external supply.
5. Safety and Diagnostics
o Activates caliper brakes or emergency locks if abnormal torque spikes or misalignments are detected.
o Maintains shaft stability through continuous monitoring of bearing loads and tank descent speed.
6. Mode Switching (Retrofit ↔ Standalone)
o In retrofit mode, coordinates torque transfer to the turbine shaft.
o In standalone mode, directs torque to the pump drive shaft for water head recovery.
By integrating all these functions, the PLC forms the nervous system of the invention, ensuring smooth, synchronized, and safe operation of all moving components while maximizing energy efficiency.

Industrial Applicability
• Hydropower retrofits: Enhances existing Kaplan/Francis turbine output without modifying turbine runner.
• Pumped storage plants: Functions as a novel low-head pumped storage mechanism.
• Energy recovery: Utilizes draft tube water flow otherwise wasted.
• Reduced wear and vibration: Anti-jerk system ensures long operational life. , Claims:1. A gravity-assisted hydropower system comprising a spiral track, a plurality of water-receiving tanks, and a vertical main shaft, wherein said tanks descend along the spiral track under gravity, imparting torque to the shaft.
2. The system of claim 1, configured as:
(a) a retrofit mode to provide supplementary torque to a Kaplan or Francis turbine drive shaft, and
(b) a standalone mode to drive a pumping unit for re-establishing water head in pumped storage applications.
3. The system of claim 1, further comprising an auxiliary shaft disengagement system, wherein:
(a) the auxiliary shaft is mechanically coupled to the main vertical shaft to transfer torque;
(b) the auxiliary shaft is mounted on a slider assembly at tank bottom configured to move along a predefined lateral channel;
(c) an electrically operated roller assembly driven by a dedicated motor initiates controlled lateral movement of the slider assembly, thereby retracting the auxiliary shaft from the main vertical shaft; and
(d) the slider assembly ensures precise, shock-free, and aligned disengagement of the auxiliary shaft to prevent drag, frictional resistance, or parasitic torque during tank resetting.
4. The system of claim 1, wherein each tank is configured to receive water at an upper section from draft tube discharge, descend along the spiral track under gravity, and empty upon reaching the bottom.
5. The system of claim 1, further comprising a regenerative braking unit at the lower end of the spiral track to recover kinetic energy from the descending tanks,
(a) wherein recovered braking energy is used exclusively for initiating tank descent on the track, actuating the auxiliary sliding shaft, operating flow-controlled valves, and in wireless electronic PLC operated system.
(b) wherein said braking energy is further used to power pre-spin motors in the anti-jerk engagement system.
6. The system of claim 1, wherein an anti-jerk engagement system is provided comprising a pre-spin motor, encoder, electromagnetic clutch, dog clutch, torsional damper, and ratchet mechanism.
7. The system of claim 6, wherein said anti-jerk engagement arrangement enables gradual synchronization of tank torque with the main shaft, thereby preventing jerk loads and vibration.
8. The system of claim 1, wherein the tanks are fabricated from lightweight composite material to minimize lifting energy during resetting.
9. The system of claim 1, wherein the tank lifting mechanism comprises:
(a) a counterweight tank hydraulically connected to the main tank through a flow control valve and drain pipe,
(b) wherein water is gravitationally transferred from the emptied tank into the counterweight tank,
(c) wherein the increase in counterweight mass produces downward displacement that passively lifts the emptied tank upward after releasing brakes, and
(d) wherein said lifting is executed without external energy input.
10. The system of claim 9, wherein the counterweight tank is mechanically coupled to the empty tank via a drum–pulley and rope arrangement, such that downward counterweight motion produces proportional upward motion of the empty tank, restoring it to its filling position.