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PRINCIPLES OF THE OPERATIONAL MANAGEMENT FOR A HYDROPOWER PLANT DISPATCHING
IFAC Workshop ICPS'07 2007, July 09-11 Cluj-Napoca, Romania
PRINCIPLES OF THE OPERATIONAL MANAGEMENT FOR A HYDROPOWER PLANT DISPATCHING Mircea Ordean1, Eva-Henrietta Dulf2, Clement Festila2 1
S.C. Hidroelectrica SA, Cluj Subsidiary [email protected] 2 Technical University of Cluj-Napoca, Faculty of Automation and Computer Science, e-mail: [email protected]
Abstract: An important amount of the Electric Power Generation (EPG) company costs is given by the maintenance costs. The implementation of a SCADA system in the hydropower plant enables the improvement of the maintenance, management and general control strategy. Based on the new and large possibilities of the SCADA-systems, the actual paper presents (in accord to the legal frame) the fundaments for the implementation of the Operational Management System (OMS) for the Hydro-electric Power Plant belonging to the general system of the Hydraulic Power Plant. The target of the OMS is to create a general Hydro-power Plant Dispatcher (HPD) for the whole chain of Hydroelectric Stations from the Somes-river (Ordean, 2005). The local Information Net of each Power Station (already in operation) is connected to the HPD in order to supervise the station operation, but also to control, directly through HPD, the equipment of the Hydro-electric station. Keywords: SCADA system, hydro-power plants, hydro-electric stations.
1. INTRODUCTION. THE ROLE AND THE MAIN FUNCTIONS ASKED BY THE OPERATIONAL MANAGEMENT AT THE (HPD) LEVEL
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to supervise the operational schemes and the normal/ abnormal values of the operational variables and/ or parameters; - to estimate the operation station states in order to prevent the non-desired events, through proper actions and anticipation monitoring program. The primary information acquired at the HPD level can be classified on the basis of the operational functions (Wiebe, 2000; Weigant, 1999): a. recording and registration for variables, state-transitions, visual signals and events for all equipment operating regime; b. checking if main variables remain in some prescribed range; c. estimation (using mathematical models) of the equipment status; d. optimal management of the water resources, minimization of the flood effect;
The HPD will achieve the operational management: 1. of the equipment from each Power HydroStation 2. of the information transfer equipment between stations, on one side, and between stations and HPD, on the other side 3. will coordinate the complex water management (water sources, irrigation, flood control) The concrete aims of the HPD operational management are: - to supervise and to provide for the continuous operation of the station equipments;
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e.
electrical power and energy records for each power station; f. records for influent – and effluent – flow rates on each electrical power unit and for on each electrical power station; g. collecting real-time data for the hydropower balance for each reservoir and for the whole system; h. based on the recorded data, the conceiving of a hydrological forecast for 1, 6, 24 hour and for 7 days. Supplementary, using primary collected information and adequate software, the HPD settles (Lopez, 2000; Siemens, 2005a, b): a. the optimal usage of the water resources, taking into account the reservoirs capacity, forecasted inflow rate, available power groups in each power station and the typical operation hydro-power system rules; b. the assessments for the available electrical power (for long-time and short-time) as information for the National Power System; c. the optimal load set points (active power, reactive power) for the hydro-electric power stations; d. the power-frequency control; e. the voltage level control in high-voltage stations; f. to perform the imposed switches; g. remote control of the circuit breakers, electrical power equipment and of the outflow rates; h. to supervise the typical devices of the information system (IS); i. in the case of incident, coordinates the activities in order to reject the incident effects (in accord to the legal frame); j. manages the water evacuation in order to prevent the flood effects; k. processes the collected data (reports) for the dispatcher of higher level; l. performs a general analysis of the whole power hydraulic plant: - turbine-generator groups performance; - maximum available power of each electric power station; - events analysis for a given time-period; - analysis of the relay protection status and mode of operation; - assessment of the power equipment condition monitoring.
2.
breakers, hydraulic pumps/ equipment, protection relays, etc. Outside the “active time”: a. management of the maintenance actions related to the power equipment b. management of the dedicated equipment for data collection, transmission, telecommunication; c. supplying of operational information/ data for marketing and financial administration of the delivered electrical energy
3. REQUIREMENTS FOR THE INFORMATION QUALITY. OPTIMAL INFORMATION PRESENTATION A special care must be dedicated to the information quality: to be in a concise form, without unnecessary data, but sufficient for the manager to know precisely the actual situation. Information must have a synthetic character, both in: - qualitative form: able to express or to suggest the process evolution, critical (present or future) level of parameters, etc., or in - quantitative form as an additional information, necessary in normal and critical situations. Another characteristic are to mention: 1. Information unicity: only one (unique) logical interpretation is possible; 2. Information consistence: if an information is connected (in some way) to other information, any change of the second information asks a change of the first information too; 3. Information accessibility: the user must have the possibility to solve his information necessity from only one working post; 4. Responsibility for the information correctness: it must be possible to check in each moment who generated and who changed the information; 5. Information safety and secret: is based on the rule-set which enables the access to the data –base.
4. TYPICAL INFORMATION FOR THE OPERATIONAL MANAGEMENT 2. OPERATIONAL CONTROL USING IT The operational management achieved by the Hydropower Plant Dispatcher is based on: measurements, signals, remote-control and remote set point. 1. The measured variables are divided in: a. main variables (Ordean, 2005 ; Siemens, 2005 a, b, c)
The Information Systems, as components of HPD perform a series of specific tasks. 1. Inside the “active time” (operating time, real time): supervision, control and operational management of the main power equipment: generators, transformers,
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- active and reactive power of each turbine – generator group; - active and reactive power of the power station and of the group of stations; - active and reactive power transferred on the bus of the tielines; - power station bus voltage; - high-voltage station voltage; - power station bus frequency; - high voltage station terminal frequency; - stator and rotor synchronous generator currents; - turbine-generator bearing temperature. b. secondary variables: level (upstream and - water downstream); - inflow and outflow rate; - electrical energy balance; - auxiliary electrical energy consumption in power stations; - hydrological and meteorological data. 2. The signals are divided in: a. state signals for - closing/ opening degree for water valves; - breakers, disconnectors; - control system components; - transformer winding tapping position of the power transformer. b. general purpose signals: - warning and alarm signals by the limits surpassing; - incident signals; - power station faults; - protective relaying actions; - water level in reservoirs; - valve faults; - state faults in information system data acquirement. 3. Remote control - start-stop for turbine-generator group; - parameter settling for control equipment; - remote-measuring request. 4. Remote adjustments: - active power set point for generators; - reactive power set points for generators; - frequency-power coordinated control.
The collected and processed data, in a synthetic mode, can be presented to the dispatcher on a dedicated display, at local (power station) or global (power plant) level. The dispatcher is able to control the whole system: - breakers closing/ opening; - power group start/ stop; - active and reactive power group locating. The control orders are based on: - optimization software and on - control orders from the higher level control dispatching units.
6. SCADA (SUPERVISORY CONTROL AND DATA ACQUISITION) TYPE FUNCTIONS IN THE HPD A version of a SCADA system is already in use for the supervising and control of the Hydro-power plant and it was proven its advantages: - data acquisition and exchange; - sequence of events recording; - data processing - post disturbance review; - in the limits of a given time-period (for electrical, electro-mechanical, mechanohydraulic phenomena) are started data sets with the values of the main parameters in order to conclude about the fault-origine, development, etc. - historical information; - remote-control, remote-adjustments; - tagging: helps to the dispatcher; - user interface - alarming - word processing - information system supervising, configuration and maintenance.
7. CONCLUSIONS Using the real time capabilities offered by the SCADA systems implemented in the hydro power plants, it is possible to improve the maintenance strategy, integrate and synchronize the information from disparate systems in a global interface to support the operators in different conditions. The database created by SCADA system and the knowledge based component created during the exploitation and overall equipment maintenance will offer the possibility to establish the future maintenance strategies. The equipment functional status analysis, operating mode in real-time and offline investigation achieved by the system represent a useful support to examine/change the maintenance technology.
5. STRUCTURE AND ADVANTAGES OF THE INFORMATION SYSTEM OF THE HPD (Modbus, 2002; Hyraulic Power Plant Somes) The operational management, suspension and control is based on the local net – Ethernet – for the acquirement and processing of the data supplied by each electric power station.
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REFERENCES ↵ Lopez, Orlando (2000), Qualification of SCADA Systems, Davis Horwood International Publishers, Limited (DHI) Modbus-IDA (2002), Modbus over Serial Line, version 1.0, December, 2002. Ordean Mircea et al. (2005), Hydro- electric power plants SCADA system applied on the Somes River, National Conference, Sibiu, Romania Randy Kondor, SCADA Deployment using OPC Siemens (2005), Human Machine Interface Systems, Catalog ST 80, 2005. Siemens (2005), Industrial Communication for Automation and Drives, Catalog IK PI, 2005. Siemens (2005), Products for Totally Integrated Automation and Micro Automation, Catalog ST 70. Tomas Wollmann, Miloslav Mysik, Martin Stianko, Martina Pelantova (2002), OPC Server for Communication with PLC Simatic S7 Series 300 and 400 –User Manual Weigant, Jeff (1999), Creating HMI/SCADA Industrial Applications Using Microsoft Access, Jeff Weigant Wiebe, Michael (2000), A Guide to Utility Automation: Amr, Scada, and It Systems for Electric Power, Pennwell Publ. *** (2006) VA TECH SAT – NEPTUN – Power Plant Management; *** (Feb. 2003) General Electric Intl Inc. Bently Nevada Romania – Managing Hydroelectric Turbine/Generators *** Handbook of Scada (Supervisory Control and Data Acquisition) Systems, Elsevier Science *** MiCOM P342, P343 Generator Protection Relays, ALSTOM, 2005 *** Hydraulic-Power Plant “Somes”, Hidroelectrica S.A – Subsidiary Hidrocentrale Cluj
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PRINCIPLES OF THE OPERATIONAL MANAGEMENT FOR A HYDROPOWER PLANT DISPATCHING Mircea Ordean1, Eva-Henrietta Dulf2, Clement Festila2 1
S.C. Hidroelectrica SA, Cluj Subsidiary [email protected] 2 Technical University of Cluj-Napoca, Faculty of Automation and Computer Science, e-mail: [email protected]
Abstract: An important amount of the Electric Power Generation (EPG) company costs is given by the maintenance costs. The implementation of a SCADA system in the hydropower plant enables the improvement of the maintenance, management and general control strategy. Based on the new and large possibilities of the SCADA-systems, the actual paper presents (in accord to the legal frame) the fundaments for the implementation of the Operational Management System (OMS) for the Hydro-electric Power Plant belonging to the general system of the Hydraulic Power Plant. The target of the OMS is to create a general Hydro-power Plant Dispatcher (HPD) for the whole chain of Hydroelectric Stations from the Somes-river (Ordean, 2005). The local Information Net of each Power Station (already in operation) is connected to the HPD in order to supervise the station operation, but also to control, directly through HPD, the equipment of the Hydro-electric station. Keywords: SCADA system, hydro-power plants, hydro-electric stations.
1. INTRODUCTION. THE ROLE AND THE MAIN FUNCTIONS ASKED BY THE OPERATIONAL MANAGEMENT AT THE (HPD) LEVEL
-
to supervise the operational schemes and the normal/ abnormal values of the operational variables and/ or parameters; - to estimate the operation station states in order to prevent the non-desired events, through proper actions and anticipation monitoring program. The primary information acquired at the HPD level can be classified on the basis of the operational functions (Wiebe, 2000; Weigant, 1999): a. recording and registration for variables, state-transitions, visual signals and events for all equipment operating regime; b. checking if main variables remain in some prescribed range; c. estimation (using mathematical models) of the equipment status; d. optimal management of the water resources, minimization of the flood effect;
The HPD will achieve the operational management: 1. of the equipment from each Power HydroStation 2. of the information transfer equipment between stations, on one side, and between stations and HPD, on the other side 3. will coordinate the complex water management (water sources, irrigation, flood control) The concrete aims of the HPD operational management are: - to supervise and to provide for the continuous operation of the station equipments;
-209-
e.
electrical power and energy records for each power station; f. records for influent – and effluent – flow rates on each electrical power unit and for on each electrical power station; g. collecting real-time data for the hydropower balance for each reservoir and for the whole system; h. based on the recorded data, the conceiving of a hydrological forecast for 1, 6, 24 hour and for 7 days. Supplementary, using primary collected information and adequate software, the HPD settles (Lopez, 2000; Siemens, 2005a, b): a. the optimal usage of the water resources, taking into account the reservoirs capacity, forecasted inflow rate, available power groups in each power station and the typical operation hydro-power system rules; b. the assessments for the available electrical power (for long-time and short-time) as information for the National Power System; c. the optimal load set points (active power, reactive power) for the hydro-electric power stations; d. the power-frequency control; e. the voltage level control in high-voltage stations; f. to perform the imposed switches; g. remote control of the circuit breakers, electrical power equipment and of the outflow rates; h. to supervise the typical devices of the information system (IS); i. in the case of incident, coordinates the activities in order to reject the incident effects (in accord to the legal frame); j. manages the water evacuation in order to prevent the flood effects; k. processes the collected data (reports) for the dispatcher of higher level; l. performs a general analysis of the whole power hydraulic plant: - turbine-generator groups performance; - maximum available power of each electric power station; - events analysis for a given time-period; - analysis of the relay protection status and mode of operation; - assessment of the power equipment condition monitoring.
2.
breakers, hydraulic pumps/ equipment, protection relays, etc. Outside the “active time”: a. management of the maintenance actions related to the power equipment b. management of the dedicated equipment for data collection, transmission, telecommunication; c. supplying of operational information/ data for marketing and financial administration of the delivered electrical energy
3. REQUIREMENTS FOR THE INFORMATION QUALITY. OPTIMAL INFORMATION PRESENTATION A special care must be dedicated to the information quality: to be in a concise form, without unnecessary data, but sufficient for the manager to know precisely the actual situation. Information must have a synthetic character, both in: - qualitative form: able to express or to suggest the process evolution, critical (present or future) level of parameters, etc., or in - quantitative form as an additional information, necessary in normal and critical situations. Another characteristic are to mention: 1. Information unicity: only one (unique) logical interpretation is possible; 2. Information consistence: if an information is connected (in some way) to other information, any change of the second information asks a change of the first information too; 3. Information accessibility: the user must have the possibility to solve his information necessity from only one working post; 4. Responsibility for the information correctness: it must be possible to check in each moment who generated and who changed the information; 5. Information safety and secret: is based on the rule-set which enables the access to the data –base.
4. TYPICAL INFORMATION FOR THE OPERATIONAL MANAGEMENT 2. OPERATIONAL CONTROL USING IT The operational management achieved by the Hydropower Plant Dispatcher is based on: measurements, signals, remote-control and remote set point. 1. The measured variables are divided in: a. main variables (Ordean, 2005 ; Siemens, 2005 a, b, c)
The Information Systems, as components of HPD perform a series of specific tasks. 1. Inside the “active time” (operating time, real time): supervision, control and operational management of the main power equipment: generators, transformers,
-210-
- active and reactive power of each turbine – generator group; - active and reactive power of the power station and of the group of stations; - active and reactive power transferred on the bus of the tielines; - power station bus voltage; - high-voltage station voltage; - power station bus frequency; - high voltage station terminal frequency; - stator and rotor synchronous generator currents; - turbine-generator bearing temperature. b. secondary variables: level (upstream and - water downstream); - inflow and outflow rate; - electrical energy balance; - auxiliary electrical energy consumption in power stations; - hydrological and meteorological data. 2. The signals are divided in: a. state signals for - closing/ opening degree for water valves; - breakers, disconnectors; - control system components; - transformer winding tapping position of the power transformer. b. general purpose signals: - warning and alarm signals by the limits surpassing; - incident signals; - power station faults; - protective relaying actions; - water level in reservoirs; - valve faults; - state faults in information system data acquirement. 3. Remote control - start-stop for turbine-generator group; - parameter settling for control equipment; - remote-measuring request. 4. Remote adjustments: - active power set point for generators; - reactive power set points for generators; - frequency-power coordinated control.
The collected and processed data, in a synthetic mode, can be presented to the dispatcher on a dedicated display, at local (power station) or global (power plant) level. The dispatcher is able to control the whole system: - breakers closing/ opening; - power group start/ stop; - active and reactive power group locating. The control orders are based on: - optimization software and on - control orders from the higher level control dispatching units.
6. SCADA (SUPERVISORY CONTROL AND DATA ACQUISITION) TYPE FUNCTIONS IN THE HPD A version of a SCADA system is already in use for the supervising and control of the Hydro-power plant and it was proven its advantages: - data acquisition and exchange; - sequence of events recording; - data processing - post disturbance review; - in the limits of a given time-period (for electrical, electro-mechanical, mechanohydraulic phenomena) are started data sets with the values of the main parameters in order to conclude about the fault-origine, development, etc. - historical information; - remote-control, remote-adjustments; - tagging: helps to the dispatcher; - user interface - alarming - word processing - information system supervising, configuration and maintenance.
7. CONCLUSIONS Using the real time capabilities offered by the SCADA systems implemented in the hydro power plants, it is possible to improve the maintenance strategy, integrate and synchronize the information from disparate systems in a global interface to support the operators in different conditions. The database created by SCADA system and the knowledge based component created during the exploitation and overall equipment maintenance will offer the possibility to establish the future maintenance strategies. The equipment functional status analysis, operating mode in real-time and offline investigation achieved by the system represent a useful support to examine/change the maintenance technology.
5. STRUCTURE AND ADVANTAGES OF THE INFORMATION SYSTEM OF THE HPD (Modbus, 2002; Hyraulic Power Plant Somes) The operational management, suspension and control is based on the local net – Ethernet – for the acquirement and processing of the data supplied by each electric power station.
-211-
REFERENCES ↵ Lopez, Orlando (2000), Qualification of SCADA Systems, Davis Horwood International Publishers, Limited (DHI) Modbus-IDA (2002), Modbus over Serial Line, version 1.0, December, 2002. Ordean Mircea et al. (2005), Hydro- electric power plants SCADA system applied on the Somes River, National Conference, Sibiu, Romania Randy Kondor, SCADA Deployment using OPC Siemens (2005), Human Machine Interface Systems, Catalog ST 80, 2005. Siemens (2005), Industrial Communication for Automation and Drives, Catalog IK PI, 2005. Siemens (2005), Products for Totally Integrated Automation and Micro Automation, Catalog ST 70. Tomas Wollmann, Miloslav Mysik, Martin Stianko, Martina Pelantova (2002), OPC Server for Communication with PLC Simatic S7 Series 300 and 400 –User Manual Weigant, Jeff (1999), Creating HMI/SCADA Industrial Applications Using Microsoft Access, Jeff Weigant Wiebe, Michael (2000), A Guide to Utility Automation: Amr, Scada, and It Systems for Electric Power, Pennwell Publ. *** (2006) VA TECH SAT – NEPTUN – Power Plant Management; *** (Feb. 2003) General Electric Intl Inc. Bently Nevada Romania – Managing Hydroelectric Turbine/Generators *** Handbook of Scada (Supervisory Control and Data Acquisition) Systems, Elsevier Science *** MiCOM P342, P343 Generator Protection Relays, ALSTOM, 2005 *** Hydraulic-Power Plant “Somes”, Hidroelectrica S.A – Subsidiary Hidrocentrale Cluj
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