1. MICRO HYDROELECTRIC POWER PLANT WITH CHAIN TURBINE
Nguyen Minh Duy

2. Content Overview about hydroelectric power plant
Analysis chain turbine
Governor using for chain turbine
Work in the future

3. Hydropower to Electric Power
Potential Energy
Kinetic Energy
Electrical Energy
Mechanical
Energy
Electricity

4. Hydropower to Electric Power

5. How Hydropower Works
Water from the reservoir flows due to gravity to drive the turbine.
Turbine is connected to a generator.
Power generated is transmitted over power lines.

6. How Hydropower Works (2)
A water turbine that cover the energy of flowing or falling water into mechanical energy that drives a generator, which generates electrical power. This is a heart of hydropower power plant.
A control mechanism to provide stable electrical power. It is called governor.
Electrical transmission line to deliver the power to its destination.

7. Vietnam Hydroelectric Potential

8. Vietnam Hydroelectric Potential (2)
Vietnam, the nation yearly average of rainfall is about 1,861mm.
There are more than 2,200 big-to-small rivers and streams. So Vietnam is rich hydropower resource.
Vietnam is agricultural country (agriculture: 20.1%). This is a goal to invest SHP.

9. Sizes of Hydropower Plants
Pico hydroelectric plant
Up to 10kW, remote areas away from the grid
Micro hydroelectric plant
Capacity 10kW to 300kW, usually provided power for small community or rural industry in remote areas away from the grid
Small hydroelectric plant
Capacity 300kW to 1MW
Mini hydroelectric plant
Capacity above 1MW
Medium hydroelectric plant
MW usually feeding a grid
Large hydroelectric plant
More than 100 MW feeding into a large electricity grid

10. Micro Hydropower Systems
Many creeks and rivers are permanent, they never dry up, and these are the most suitable for micro-hydro power production
Micro hydro turbine could be a waterwheel
Newer turbines : Pelton wheel (most common)
Others : Turgo, Crossflow and various axial flow turbines

11. Turbine Classified

12. Impulse Turbines
Uses the velocity of the water to move the runner and discharges to atmospheric pressure.
The water stream hits each bucket on the runner.
High head, low flow applications.
Types : Pelton turbine, Turgo turbine

13. Pelton Turbine

14. Turgo Turbine

15. Reaction Turbines Combined action of pressure and moving water.
Runner placed directly in the water stream flowing over the blades rather than striking each individually.
Lower head and higher flows than compared with the impulse turbines.

16. Francis Turbine

17. Kaplan Turbine

18. Turbine Selection Chart

19. Chain Turbine It is a gravity machine
It is built up of two parallel chain systems joint together at the chains with a series of buckets.
The flow rater entering the buckets is controlled by the water valve through a motor to open or close the valve.
Buckets fill full of water go down to bring to rotary sprocket system.

20. Analysis of the Chain Turbine
With flow rate is 1m3/s, and the head is 20m.
Assume H1=19m, H2=1m, the diameter of the sprocket is 1m.

21. Analysis of the Chain Turbine (2)
The gross power output:
Apply the principle of work and energy with the bucket of chain turbine:
The maximum speed of bucket
The angular velocity the sprocket would be
The rotational speed of the sprocket would be

22. Analysis of the Chain Turbine (3)
Number of buckets in chain turbine
Number of buckets
The volume of a bucket (m3) 8
0.50 10
0.40 12
0.36

23. Analysis of the Chain Turbine (4)
The power output is
The power out of the turbine shaft
The efficiency of the chain turbine is given by

24. Analysis of the Chain Turbine (5)
Rotational velocity of sprocket depends on the distance of between two shafts of turbine H1.
Rotational velocity of turbine shaft is slow, so it cannot directly connect with generator. It need a power transmission
Efficiency of chain turbine is low.

25. Advantages of Chain Turbine
It is run-of-river power plant.
Do not worry about the turbidity of water.
There is no danger of cavitations.
It is simple to construct, repaired and maintenance.

26. Disadvantages of Chain Turbine
The slow rotation of chain turbine leads to high speed ratios when connect to generator at 600 rpm – 1500 rpm.
This chain turbine operation is very noise.
Structure of turbine is very big

27. Governor
To maintain the generator at a constant 50Hz frequency, it is necessary to maintain the generator shaft at a constant rotational speed.
In the independent hydroelectric power plant, the rotational speed of the micro hydro power generator can be change when loads are added or subtracted from the electrical system.

28. Governor (2)
The system frequency can be maintained constant by eliminating the mismatch between generator and load.
Governor is to receipt the frequency signal from the output of generator.
And it is compared with standard frequency signal.
From these results, governor output signal is coming-out to control the valve of water at the entrance to the turbine.

29. Transfer Function Block Diagram of Hydro Plant
power system gain constant (Hz/p.u)
nominal starting time of water in penstock (s)
integral gain constant for servo system
proportional gain controller constant for servo motor

30. Governor Transfer Function
Chain Turbine transfer function
water starting time at full load
So transfer function of chain turbine is

31. Generator Transfer Function
Assume nominal load
Frequency 50Hz
The latter load assumption yields
So, the system gain constant and time constant are given by
The transfer function of generator

32. Transient responses of system for step changes in load, showing deviations in system frequency

33. Transient responses of system for step changes in load, (1
Transient responses of system for step changes in load, (1.5kW) for different integral gain value, showing deviations in system frequency (1)

34. Transient responses of system for step changes in load, (1
Transient responses of system for step changes in load, (1.5kW) for different integral gain value, showing deviations in system frequency (2)

35. Transient responses of system for step changes in load, (1
Transient responses of system for step changes in load, (1.5kW) for different integral gain value, showing deviations in system frequency (1)

36. Transient responses of system for step changes in load, (1
Transient responses of system for step changes in load, (1.5kW) for different integral gain value, showing deviations in system frequency (2)

37. Governor Discussion It is more flexible than classical governor.
This governor effectively eliminate the frequency deviations due to load disturbances for different nominal loadings of the system
It is importance as the saved water can be used for irrigation.

38. Work in the Future
In China, YiuHwa Engineering Company is building a hydroelectric power plant with chain turbine to experiment and research with capacity 200kW.
This plant has two turbines and built with head 20m and flow rate 1.03m3/sec

39. THANK YOU