MHP 5 DEPARTMENT OF ENERGY ENERGY UTILIZATION MANAGEMENT BUREAU

Transcription

1 MHP 5 DEPARTMENT OF ENERGY ENERGY UTILIZATION MANAGEMENT BUREAU Micro-hydropower Operator Training Manual May 2009

2 This manual was developed by the Department of Energy (DOE) through the technical assistance under the Project on Sustainability Improvement of Renewable Energy Development for Village Electrification in the Philippines which was provided by the Japan International Cooperation Agency (JICA).

3 Table of Contents 1. General Scope Objectives Roles of Operators Operation Work Intent of Operation Basic operation Operations in the Event of an Emergency Others (other types of operation) Patrol Patrol for hydropower stations Daily patrol items Maintenance Breakdown and Preventive Maintenance Daily Maintenance Maintenance for the trouble and failure Periodic Maintenance Recording Model Training Schedule for the training of new operators Amendment of the manual... 13

4 LIST OF ANNEXES ANNEX 1 : Check sheet

5 1. General Micro-hydropower plants for rural electrification should be operated and maintained by well-trained operators to ensure a stable supply of electricity to electrified communities. This manual specifies operator-training concepts that are to be put into practice at the project site prior to the handing over of the facilities. Specific contents of the actual training, therefore, shall be adequately reviewed to meet the practical conditions of which this manual will serve as a reference. 2. Scope This manual shall be used as instructional material for DOE staff and/or designated implementers who have been assigned to conduct operator training. 3. Objectives The objectives of this manual are: (1) To identify the roles and responsibilities that operators should undergo in order to properly operate and maintain micro-hydropower plants, and (2) To assist the project implementer in preparing operation and maintenance manuals for newly constructed micro-hydropower plants. 4. Roles of Operators Micro-hydropower plants must be operated and maintained in strict compliance with O & M (Operation and Maintenance). In general, operators of micro hydropower plants should understand the following items: (1) Operators must efficiently conduct O & M of micro-hydropower plants in strict compliance with the rules and regulations. (2) Operators must familiarize themselves with all plant components and their respective performance or functions. Furthermore, they should also be familiar with prompt recovery emergency measures should an accident occur. (3) Operators must always check the condition of facilities and equipment. If trouble is found or an accident occurs, they must inform the person in charge and try to solve the problem. (4) Operators must try to prevent any accidents. Preventative measures such as equipment repair and the improvement of the facilities should be implemented as necessary. (5) An operation and maintenance manual should be prepared for each plant before the start of its operation. 1

6 5. Operation Work The operation of micro-hydropower plants is to not only generate electric power, but also to control generation equipment, supply stable, high quality electricity to consumers, and maintain the condition of all facilities. Most rural electrification micro-hydro plants are not equipped with suitable automatic control systems and protection equipment due to budget constraints. Therefore, it is necessary for operators to stay at or near the plant to monitor control equipment and to undertake immediate measures in the case of an emergency. 5.1 Intent of Operation Hydropower station operators should be highly motivated to keep their power stations in good condition to ensure a stable supply of electric power. Operators should be aware of any signs and/or signals indicating equipment malfunction and take advance preventative measures. Examples of the intention of operation are listed below. (1) Familiarize oneself with operation-related regulations, rules, and manuals of the power station, distribution lines, and loads. (2) Familiarize oneself with the civil structures, electric circuits, control system, etc. of the power station in detail. (3) Grasp the operational conditions of the power station (4) Maintain highly efficient operations. (5) Avoid abnormal operation (e.g. low output operation) because of damage to water turbines by large vibrations, cavitation damages, etc. (6) Check and maintain a grasp of the equipment conditions via periodic and methodic patrolling of the power station. (7) Compare and contrast past recorded data with present data to confirm the equipment conditions. 5.2 Basic operation (1) Pre-operational Check points Before operation commences, the following facilities and equipment must be checked by operators to ensure that they are in proper operating condition. Especially for long-term operation, it is of particular importance that these items are checked thoroughly. 2

7 a. Transmission and distribution lines (a) Line and pole damage (b) Nearby branches (c) Other obstacles b. Waterway facilities (a) Structural damage (b) Sand sedimentation in front of the intake (c) Suspended trash at the screens (d) Sand sedimentation in the settling basin and the forebay c. Turbine, generator, and controller (a) Visual inspection (b) Wear of the brush (c) Insulation resistance of the circuits (2) Starting operation Start-up of operation is as follows (typical example): (a. Preparation) (a-1) Close the flushing gate of the intake weir (a-2) Open the intake gate and intake water into the waterway system. (b. Starting operation) (b-1) Open the inlet valve gradually. (b-2) If there is a guide vane, open the inlet valve fully, and then open the guide vane gradually. (b-3) Use a controller (e.g. ELC) if one exists. Confirm that voltage and frequency or rotating speed increase up to the regulated value by guide vane (or inlet valve). (b-4) Turn the load switch on (parallel in). (b-5) Control the inlet valve or guide vane so that voltage and frequency are within the regulated range. The start-up procedure is designed based on the equipment at each power station. Based on the knowledge of each machine, it is important to understand the logic behind these steps. 3

8 Prior to starting operation of the main units, the following conditions have to be generally kept. These conditions are called the Preparation for operation. (a-1)(a-2) Close the flushing gate of the intake weir and open the intake gate and intake water into the waterway system. The water turbine is driven by water from the waterway system. If the water flow is shut off by the intake gate or valve, water cannot be fed to the water turbine. In situations where the ability to close the intake gate (or valve) is limited, the water remaining in the penstock flows down by the force of its own weight after the opening of the inlet valve (and guide vane), but supplemental air cannot go into the penstock. This lowers the pressure within the penstock. In the worst case scenario, the build up of air pressure breaks the penstock. (a-3) Others (a-3-1) Bearing lubricant condition Bearings are delicate parts that maintain stable operation of the units. Periodic application of grease is important for stable and long-term use of the bearings and main units. When lubrication of bearings is insufficient for operations, this means that the bearings have burned out and must be replaced. (a-3-2) Cooling water of dummy load for ELC Generator frequency output is controlled by the ELC. The ELC uses a dummy load (a resistance unit) to consume electric power over the necessary load supply at that time. If the dummy load is cooled by water, operators should confirm the water level of the dummy load before operation begins. (The typical cooling methods of dummy loads are water cooling and air cooling.) (a-3-3) Protection relays for emergency stop are not activated When a series of failures occurs in the units, protection relays (and automatic cut-off by circuit breakers) are activated for an emergency shutdown of the units. Once the failures are corrected, they can be manually reset by the operators. The excitation current of the AVR system increases the terminal voltage of the generator. When it reaches its approximate rated voltage (and frequency or rotation speed reaches its rated value), operators turn on the load switch (generator circuit breaker) to connect the generator to the transmission (distribution) lines. 4

9 (3) Roles of Operators during Operation Operators must maintain control over the equipment so that the supply of quality electricity may be realized in order to maintain equipment conditions and ensure safety factors as follows: (c-1) Control the inlet valve or guide vane so that voltage and frequency are within their regulated range. (c-2) Check for equipment and noise vibration, and stop operations if necessary. (c-3) Check the temperature of the equipment. (c-4) Check the equipment conditions. Stop operation and apply the appropriate countermeasures if necessary. (c-5) Record operation results and equipment condition (4) Stopping Operation In order to avoid longer runaway speed of the turbine and the generator, the procedures for stopping operation are as follows: (d-1) Close the inlet valve or the guide vane. (d-2) Cut load switch off (load rejection). (d-3) Close the inlet valve and the guide vane completely. (d-4) Close the intake gate. If the load is suddenly cut due to an accident, the operator must close the inlet valve or the guide vane immediately to avoid prolonged periods of the runaway speed of the turbine and the generator. 5.3 Operations in the Event of an Emergency (1) Flood Conditions In general, micro-hydropower plants can operate even during flood conditions. However, when the river becomes muddy leading to a possibility of sand and/or soil intrusion into the facilities, plant operations should be stopped by closing the intake gate. After the floodwater recedes, operators must inspect all facilities prior to resuming operation. (2) Earthquake Operators must inspect all facilities after a big earthquake as follows: 5

10 Structural damage Misalignment of the turbine and the generator shaft Damage of the other electrical equipment Others (2) Water Shortage / Drought Conditions Micro-hydropower plants should basically be designed in accordance with the amount of water discharge in the dry season. However, in the case of drought conditions, operators must stop operation to prevent turbine damage. (4) Accidents (Troubles) When accidents occur, operators must stop operation, investigate the cause, and then try to recover operation as soon as possible. An operator s roles are as follows: (a) Immediately inform the person in charge of the accident. (b) Investigate the details of the accident. (c) Investigate the causes of the accident. (d) Recover operation as soon as possible if operators can determine the causes and perform the necessary repairs by themselves. (e) Contact technical advisors, manufacturers, or equipment suppliers and request them to perform the repair(s) if the operators cannot discover the cause(s) and/or cannot perform the repair(s) by themselves. Preparations that operators should make in advance are as follows: (a) Discuss possible countermeasures for the trouble with technical advisors, manufacturers or equipment suppliers. (b) Report the accidents to the DOE and LGU. 5.4 Others (other types of operation) (1) Filling of the waterway system Filling procedures for the waterway system are as follows: (a) Confirm that all flushing gates and valves of the water system are open. (b) Open the intake gate partially and input a small volume of water. (c) Close the flushing gate of the settling basin after cleaning the settling basin. (d) Close the flushing gate of the forebay after cleaning the headrace and the forebay. 6

11 (e) Close the drain valve of the penstock after cleaning the penstock. (f) Fill the penstock with water gradually. (g) Open the intake gate fully after filling up the penstock. (2) Flushing sand in front of the intake If sand sedimentation reaches the intake level, sand will be carried into the waterway system and affect the penstock and turbine blades. Therefore, in order to prepare against an outflow of sand and soil during flooding, operators must keep the intake approach open. For this purpose, operators should sometimes flush or remove the sand that has settled in front of the intake. If a flushing gate is installed at the intake weir, operators can flush sand out using the water flow by opening the gate during flooding. However, if not equipped with a flushing gate, operators must manually remove the sand from the weir. (3) Control of intake water The volume of intake water changes according to the water level of the river. Normally excess water should be released into the spillway, which is located at the settling basin or headrace. If excess water reaches the spillway of the forebay for a long period of time, it may possibly wash out the structure due to a lack of spillway capacity. Therefore, operators must control the intake gate so as to avoid excessive water spillage. 6. Patrol Operators patrol the waterway facilities, electric equipment, and transmission and distribution lines on a daily basis in order to confirm that they are in proper working order. Operators must record the results of the patrol and take countermeasures if any troubles should occur. In this manual, the definition of patrol means to conduct a visual inspection of the hydropower station and confirm the condition of the equipment, the facilities, and the surrounding areas. 6.1 Patrol for hydropower stations For the prevention of failures and faults in hydropower stations and to ensure appropriate operation and maintenance, patrols should be conducted as described below. 7

12 a. Types of patrol (a) Daily patrol The daily patrols are carried out to confirm the presence and/or absence of abnormalities at the power stations. (b) Special patrol The status of various facilities shall be checked specifically by these patrols before and after any abnormal weather conditions (heavy rainstorms, flood, etc.), and immediately after earthquakes. b. Application of the Patrol Table Checklist (a) For the daily and detailed patrol, a patrol table checklist according to the actual conditions of various facilities should be made and used. (b) The Patrol Table Checklist shall be prepared c. Recording and reports (a) Operators (or related staff) should make records of the patrol in the Patrol Table Checklists and report these results to the person in charge of whatever operation is a matter of concern. These patrol results should be kept properly to ensure easy use and access by other operators. (b) When abnormalities are found, follow-up measures must be implemented e. Points to be noted for patrols (a) Any abnormality found during a patrol must be reported to the person in charge of the indicated trouble operation, and appropriate corrective measures must be taken. In emergency cases, emergency measures should be implemented in a safe and thorough manner by the operator, and after that the person in charge of its operation should be promptly notified. (b) Patrols shall be carried out based on certain points of emphasis that were determined by taking the conditions of the hydropower station into consideration. These include not only seasonal or weather conditions, equipment characteristics and their operational conditions, but also previous records. (c) The condition of the meters, indicators, and relays should be checked appropriately, as well as the connection conditions of each terminal. 8

13 6.2 Daily patrol items Daily patrol check items for micro-hydropower stations are as follows: Facilities and Equipment Intake and Waterway Table Daily patrol items Checking Points Suspended Trash at screen Water leakage from weir and gate Sand sedimentation Deformation or Crack in structure Remove the debris. Measures Record it and make repairs if necessary Flush out as necessary. Record and make repairs if necessary. Sedimentation Basin Sand sedimentation Flush out as necessary. Headrace Head tank (Forebay) Suspended materials along canal Sand sedimentation Leakage, deformation and Crack in structure Land slide along headrace Suspended Trash at screen Overflow from Spillway Water leakage Sand sedimentation Deformation or Crack in structure Remove the debris. Penstock Leakage and deformation Record it. Turbine Generator Load stabilizer Strange sound and vibration Leakage from housing Strange sound and vibration Temperature Belt Damage Performance of load stabilizer Damage of heater Flush out as necessary. Record it and make repairs if necessary. Remove the sand and rocks after confirming the safety. Remove the debris. Reduce water intake if overflow of water is too great. Record it and make repairs if necessary. Flush out as necessary Record it and make repairs if necessary. Record it and make repairs if necessary. Record it and make repairs if necessary. Record and make repairs if necessary. Record it Replace if necessary Check the performance Replace if necessary Transformer Leakage of oil Replace if necessary Transmission and Suspended material Remove after stopping operation. Distribution lines Approaching branch Cut it as necessary 9

14 7. Maintenance Over time some parts of the hydropower station facilities will deteriorate or wear out. Casings, guide vanes, runners, etc. often deteriorate due to cavitation damage, corrosion and erosion, or wear of areas at narrow gaps. As a result, the efficiency of the water turbines decreases little by little coupled with increasing water turbine vibration and noise. In order to maintain long-term optimal operating conditions of the micro hydropower plants, waterway facilities, electric equipment, and transmission and distribution lines should be adequately maintained. 7.1 Breakdown and Preventive Maintenance There are basically two maintenance methods concerning the maintenance of power station equipment: breakdown maintenance and preventive maintenance. Determining which method to adopt depends on the situation, equipment and the concepts of the implementers. In the case of breakdown maintenance, power stations are only stopped in the event of trouble occurring. This means maintenance expenses will inevitably ensue if trouble occurs. Moreover, power stations are run continuously at the maximum amount of generation if no trouble occurs. However, once trouble occurs a forced outage is required to fix the trouble. This means that the duration of a forced outage for breakdown maintenance will generally be longer than that of one for preventive maintenance. Further, a sufficient amount of on-hand spare parts are required for repairs to shorten the duration of the forced outage. Given these factors, breakdown maintenance is generally considered less reliable and more costly for long-term operations. Table Difference between breakdown and preventive maintenance Breakdown maintenance No need to stop power stations unless trouble occurs. No expense until trouble occurs. Forced outage Lack of spare parts delays replacement of the equipment. Reserve capacity of the power system is required. Increased risk of major damage. 10

15 Preventive maintenance Planned outage Reduction of reserve capacity based on a lower ratio of forced outages. Parts procurement before maintenance. Only replacement of consumable parts and minor repair in many cases. Necessary to stop power station or units. Regular expenses are required based on a maintenance plan. On the other hand, for preventive maintenance, power stations are stopped regularly based on a maintenance plan. However, the duration of the forced outage and probability of trouble is lower because the maintenance is conducted regularly to keep power stations operating under stable and reliable conditions. For preventive maintenance, it is crucial to formulate and coordinate maintenance plans which consist of contents, the duration of planned outages, the facilities that will be required to be stopped, etc. Each plan must be coordinated in consideration of the power system conditions. Maintenance consists of replacing consumable parts and conducting minor repairs, therefore preplanned budgetary steps and procurement are also necessary. 7.2 Daily Maintenance Operators should conduct daily maintenance if they find equipment abnormalities during their daily patrol. Daily maintenance is usually conducted without stopping the water turbine and dewatering the pipe. During the daily maintenance, the operators should be careful of rotating parts, moving parts, live parts, and so on. The operators shall engage in the following duties as daily maintenance. (a) Cleaning equipment (b) Retightening valves and volts (c) Others (refer to Daily patrol items) 7.3 Maintenance for the trouble and failure If the operators find any trouble and/or failure, they should confirm present conditions and take countermeasures to prevent the spread of accidents. The operators should also record their present condition and the countermeasures being taken. This record will serve as valuable data for the implementers. 11

16 7.4 Periodic Maintenance Operators (and maintenance staff) should conduct maintenance periodically as preventative measures. Items and frequency of periodic inspection are shown as a sample in table Table Items and frequency of periodic inspection (for example) Facilities and Equipment Checking Points Frequency Measures Supply grease to bearing Six months Turbine Bearing replacement Three years Bolt connection One year Repair Supply grease to bearing Six months Bearing replacement Three years Generator Winding insulation resistance Six months Replace the generator Load stabilizer Bolt connection One year Repair Damage of belt Six months Replace if necessary Performance of load stabilizer Six months Repair Damage of heaters Six months Replace if necessary Inlet valve Leakage One year Record and make repairs if necessary. Transformer Leakage of oil One month Replace if necessary Transmission and Distribution line Approaching branch One month Cut if necessary 8. Recording Operators must keep records of the operation and maintenance of the micro-hydropower plant. These records will help operators monitor the conduct of regular or scheduled operation and maintenance activities. It will also serve as supporting, evidential data in determining the causes of trouble in case of accidents. A sample operation record and daily patrol check sheet is shown in the ANNEX1. 9. Model Training Schedule for the training of new operators One Model Training Schedule of new operators (for new MHP (Micro Hydropower Plants)) is shown below (Table 9.1). A concrete training program is planned and designed in consideration of actual MHP site conditions. 12

17 Table 9.1 An example of Model Training Schedule Day Contents of training Notes 1 st Day AM Introduction of a MHP Roles of MHP operators General explanation General explanation Introduction of the MHP management system Based on the actual MHP PM System of the MHP Based on the actual MHP Structure of MHP facilities Characteristics of MHP equipment Based on the actual MHP Based on the actual MHP 2 nd Day Operation work of the MHP General and detailed Contents of operation work Method of operation of Civil Engineering Facilities and records Method of operation of Electrical & Mechanical Facilities and records explanation of the actual MHP. 3 rd Day Daily Patrol and Maintenance work of the MHP General and detailed Daily Patrol work and records Contents of maintenance work Examples of trouble, extraordinary conditions and the countermeasures explanation of the actual MHP. 4 th Day - 5 th Day Method of maintenance and records Site inspection of the existing MHP Experience of the operation Experience of the maintenance Discussion with the operators 10. Amendment of the manual The DOE shall review this manual annually, and amend it, if necessary, according to the surrounding circumstances in rural electrification of the country. The amended manual shall be fully authorized among the DOE and approved by Director of Energy Utilization Management Bureau of the DOE. 13

18 Civil Construction Month : No ANNEX-1 Description I Dam 1 Construction 2 Stop Log II Settling basin 1 Construction 2 Screen III Headrace 1 Construction 2 Stop Log IV Forebay tank 1 Construction 2 Screen V Penstock 1 Penstock 2 Foundation VI Power House 1 Construction 2 Sanitation VII Tailrace 1 Construction Damage Note Cause of Damage Repairing Note Repaired by Remarks: * Fill the column as the actual condition such as: (N) Normal, (B) Bad, (R) Broken Check Sheet Acknowledge Year : Daily Checking Checker Chairman Operator

19 Mechanical and electrical Month : No I Turbine 1 Runner Remarks: Description 2 Bearing turbine Plummer Block 3 Bearing 4 Pull Turbine 5 Cover pulley 6 Coupling II Panel control 1 Meter 2 Lightning rod 3 Ballast Load 4 Main Board Damage note Cause of Damage Repairing Note Repaired by Check Sheet * Fill the column as the actual condition such as: (N) Normal, (B) Bad, (R) Broken ** If there is a fatal damage, repair immediately, or coordinated with IBEKA team Telp Year : Daily Checking Acknowledge Checker Chairman Operator

20 Distribution Line No Month : Remarks : Description I Transmission 1 Pole 2 Cable 3 Connector 4 Group MCB II In house installation 1 MCB 2 Installation Cable Damage Note Cause of Damage Repairing note Repaired by Check Sheet Daily Checking * Fill the column as the actual condition such as: (N) Normal, (B) Bad, (R) Broken ** If there is problem with the distribution facility, repair immediately and fill the damage column Year : Acknowledge by Checker Chairman Operator

21 Lubricant & Spare parts Year : No Description A LUBRICATION 1 Bearing Turbine Plummer Block 2 Turbine Bearing Plummer Block 3 Turbine Generator B SPAREPARTS 1 Bearing 2 Seal 3 Coupling 4 Flat Belt 5 Others Re-setting Lubrication based on total operation hour January February March April May June July August September October November December Notet. : Fill the column with the lubrication date

22 Year : LOG BOOK Date Time Operation Start Stop Hour/ day Opening of Guide vane % Frequency meter (Hz) Note: Fill the column after installation to the house Calculation of power output = (A1+A2+A3)x220 on condition ballast 0 (zero) volt Output Volt Ampere Watt Total R-N(V1) S-N(V2) T-N(V3) A1 A2 A3 V1xA1 V2xA2 V3xA3 Watt Recorder Operator Remarks

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