See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/312115094 Automatic generation control and monitoring the mechanism of micro hydro power plant with impulse turbine and synchronous generator Conference Paper · November 2016 DOI: 10.1109/ICRAI.2016.7791249 CITATIONS READS 7 1,522 1 author: Nazib Sobhan World University of Bangladesh 2 PUBLICATIONS 7 CITATIONS SEE PROFILE Some of the authors of this publication are also working on these related projects: Electro-Mechanical Design View project All content following this page was uploaded by Nazib Sobhan on 03 January 2018. The user has requested enhancement of the downloaded file. Automatic Generation Control and Monitoring the mechanism of Micro Hydro Power Plant with Impulse Turbine and Synchronous Generator Nazib Sobhan, [email protected], +88 01764367591 The classification of hydropower scheme is given below [9]: Abstract: This paper presents automatic generation control and monitoring operation of Micro Hydro power plant (MHPP), based on Impulse Turbine, synchronous motor with permanent magnet and a servo control spear valve. The key objective of this system is to show the benefits of automatic generation control and Human Machine Interface (HMI) for MHPP. Mainly, turbine governing system covers the automatic generation part. A deflector and a servo valve are used for turbine governing system and PID controller is used to adjust with the generator output. The PID controller is used for the deflector and servo valve. The PLC is used to control the whole mechanism and SCADA is combined with PLC for monitoring and supervising the system. The proposed scheme is verified with severe MATLAB simulation result and finally a small project confirmed the feasibility of this model. The output results of both simulation and real model proves that this model can work properly in real system. Generation Large Small Mini Micro Pico 1. 2. 3. 4. 5. INTRODUCTION Can be used for rural area electrification which area are far from national grid The construction of Dam or weir is not costly as large dam The low environmental impact The plant installation can be done in a short time and also not complicated The equipment cost is not high compare to other hydro project. Now a days, PLC is used for computer based automatic control and supervising the micro hydro power plant. The concept is taken from Mae-Ngat hydro power plant under responsibility of the Electricity Generating Authority of Thailand (EGAT) [8]. The basic difference of existing model and proposed model is the type of turbine. In Mae Ngat the Kaplan turbine but in proposed model Pelton wheel type Impulse Turbine is used. This turbine is much easier to control than Kaplan Turbine. The PLC and SCADA is applied on an existing model built by both AIT Water Engineering Management (WEM) and Energy Department. The several experimental results from the existing model data indicate that the proposed turbine control system can work properly. Hydro power technology is the most widely technology among others renewable energy. More than 19% of the world’s electricity is coming from this sector. However, a large potential of hydropower scheme remains unexploited. This is because, implementation of mini hydro schemes with conventional hydraulic, electrical equipment and controllers are very expensive and uneconomical. To solve this problem alternative options and new designs have been developed by the engineers and researchers. The application of this modified new design would reduce the cost of mini hydro schemes.[1,2,3,4,12] As a result, many developing countries like Thailand, Laos and Bangladesh can use this scheme for rural electrification where interconnection of transmission line from electrical grid is uneconomical. For this, it would be now possible to use more renewable energy sources than before. 978-1-5090-4059-9/16/$31.00 ©2016 IEEE Transmission National Grid National Grid Micro Power Grid Micro Power Grid Only for Domestic Use Among them Micro Hydro Scheme is more popular. The benefits of Micro Hydro Scheme are given below: Keywords: Impulse Turbine, Servo Valve, PLC, HMI and PID I. Capacity 1000 MW < Up to 25 MW Below 1MW 6kW -100KW 5 KW> II. 175 Plant Model Description: Like every power plant this model includes impulse turbine, synchronous generator and servo valve as controlling equipment. Moreover, there is other equipment that is not described in this paper. The proposed schematic model is given below: The Impulse Turbine model is given below: Fig.2 Mathematical model of Turbine The mathematical formulation of Impulse Turbine is given below in details: The Input Power Coefficient is, Fig.1 The proposed Plant Model Cin = 2'PQ {ρ(v +U 2 )blrb N rb v} 2 Efficiency, At first the water is flowing to the turbine from the source (River, Fall) through the Dam or Weir. Then water energy is converted to water energy to mechanical energy. The formula of this conversion is given below: η= Tω ΔPQ I= v U Flow coefficient, Pw= (1/2) ρAV3 Where, Here, T=Torque, ρ=Density, v=Inlet velocity, U= Circumferal velocity, P=Pressure, Q=Flow rate, ∆P=Total Pressure Drop, r=Radius of the turbine, l=total length, N=Number of blades=blade height, k=Torque Constant. ρ =Water Density (1000 kgm-3),V= Water Speed (ms-1),A= water turbine rotor swept area (m2) and Cp= Tt u Z 0.5 u A uV 3 The initial output curve of the turbine is given below: Cp= Power Coefficient of performance The water turbine torque is given by, P T = S W s Input Power Fig.3 The Output curve of Turbine Model (Impulse Mode) Ts=Torque of water turbine Generator Model: Most of the small or micro hydro sites, synchronous generator is most preferable, because it has stable, good characteristics during normal operation and they do not need an additional DC supply for the excitation. P= Power of water turbine Ws=rotor speed of water turbine 1. Turbine Model: The generation capacity of hydropower plant depends on the turbine efficiency. Hence, choose of turbine in hydro power site is very important [8]. Recently, a new design of Impulse turbine model is invented that gives more flexibility and reliability. 978-1-5090-4059-9/16/$31.00 ©2016 IEEE Model of Servo Valve: Servo valve is main control element in micro hydro plant. Mainly, this valve is used to control the water flow through dam to turbine. As a result the output power of the prime mover can be controlled [11]. 176 The mathematical model of servo motor control valve is given below: The resultant monitoring panel is given below: 1. Home Screen Panel Fig.4 Mathematical Model of Servo Motor Control Valve mechanism Where, Kv=Valve Gain, Tv=Time rate of valve Results and Discussion: The results and output are given in some matlab simulation curves and the SCADA models. The respective parameters of the plant is given below: Turbine Flow rate,Q=0-0.11m3/s Generator Speed range=0-1200 rpm Output Power=0-4.8 KW Rated Speed (t) =1500 rpm Input Torque,Tm=37.2 Nm Damping factor, Kd=0.026 Rated Power,Pe=5.5 KW Efficiency at rated speed, ƞ=0.9 Rated voltage, V=400V Rated Current, I=7.9A Fig.6 The main Home-Screen Panel of MHPP 2.The AGC panel is given below: The final resultant curve is given below: Over Voltage Voltage Gain Normal Operation Under Voltage Time Fig.5 Load changing affect and frequency deviation of the system From , the swing equation it is shown that the change of rotor speed is depend on the difference of input mechanical power and output electrical power. The main variable is turbine input power which is depend on water flow.hence, in this model the governor is used to control the flow and thus controlling flow is the prime mechanism of automatic generation control (AGC). 978-1-5090-4059-9/16/$31.00 ©2016 IEEE 177 Fig.7 The various parameters of MHPP 3. The PID monitoring panel is given below: RESULTS&DISCUSSION: In this section, some of output graphs of the proposed micro hydro model is given which describe the system operation and analysis of the total system. Some of the graphs are given below: In this curve the change of input and output power analysis in accordance to the flow rate is discussed. The power analysis curve is given below: Fig.8 The monitoring model of PID application The proposed experimental set up is given below: Figure The change of head water level In this curve the change of input and output power analysis in accordance to the flow rate is discussed. The power analysis curve is given below: Figure 9 The proposed experimental set up This is the schematic diagram of the whole control system. The following flow chart describes the whole control mechanism: The Input is coming from Voltage & Current from the manual Circuit The Valve is finally rotate by stepper motor and makes perfect position PLC OUTPUT is connect with ARDUNIO Driver circuits run the motor with pulse signal and direction coming from the driver circuit 978-1-5090-4059-9/16/$31.00 ©2016 IEEE Figure Rate of change of power with input water flow PLC OUTPUT is connect with ARDUNIO ARDUNIO step signal is used for making proper Pulse for the Driver Circuit The turbine and generator are connected with common rotor. The output speed and frequency is significant for the model. The speed analysis curve is given below Speed and frequency changing Curve 178 6. Duangsoithing T., Kongnam C. Renovation of Turbine Control System Using PLC-Based for Small Hydroelectric Power Generation. Brief Report on Mae-Ngat Hydro power plant by Electricity Generating Authority of Thailand (EGAT). 7. Operational description of Pump as a turbine from AIT-EHMF Collaborative Project on Micro Hydro system at Asian Institute Of technology, Thailand. 8. Turbine and hydropower modeling project by SINTEF Energy Research in 2005. 9. Hydraulic Turbine and turbine Control Model for system dynamic studies under IEEE system dynamic performance. Established in 1977. 10. A. Williams (1996), “Pumps as turbines for low cost micro hydro power”, Renewable Energy Journal, Volume 9, Issues 1-4, pp.1227-1234. 11. Dolla and Vatti (2006), “ Automatic generation control of an isolated small-hydro power plant” Electrical power system research 76(2006) 889896. 12. Handmandlu and Goyal (2008), “Proposing a new advanced control technique for micro hydro power plants.” Electrical Power and Energy Systems 30 (2008) 272-282. CONCLUSION: This paper is focused on the control technique of MHPS. The automatic generation control which is formed by computerized control technique recovers the faults and crisis very quickly and effectively. This paper focus on PLC as computerized tool for system control. For validation, a small project is built as a real model. However this model cannot be done in real hydro site due to lack of budget. The simulation data is taken from the output result of the experiment in a joint venture project of Water Engineering Management (WEM) and Energy Department in AIT. Finally, there are recommendations like transformer connection and grid fault can be considered in future work. Moreover, highly communication devices like Ethernet and Optical fiber can be used for Stand-alone MHPS. REFERENCES 1. 2. 3. 4. 5. Kishor N., Singh N, Raghuvanshi A. (2006). Adaptive Intelligent hydro turbine speed identification with water and random load disturbances. Engineering Applications of Artificial Intelligence,. Laghari J., Mokhils H., Bakar A., Mahammad H. (2012).A comprehensive overview of new designs in the hydraulic, electrical equipments and controllers of mini hydro power plants making it cost effective technology. Renewable and sustainable Energy reviews,. Li L., Ma R. (2012).Design and Analysis of Comprehensive Control System for Hydro turbines. AASRI Procedia,. Marquez J, Molina M, Pacas J (2010).Dynamic modeling, simulation and control design of an advanced micro-hydro power plant for distributed generation application. . Singh R., Chelliah T., Agarwal P. (2014). Power electronics in hydro electric energy systems-A reviews. 978-1-5090-4059-9/16/$31.00 ©2016 IEEE View publication stats 179
