The whole process of power station construction needs to be controlled by the operation and maintenance personnel from the joint development, system design, construction, and completion acceptance of the preliminary project. The operation and maintenance of the power station will face various difficulties, such as poor cooperation with the construction party, rectification and delay of the problem, uneven quality of the power station, inadequacies of inefficient components, unreasonable system design, and serious construction quality. The completion of each photovoltaic power plant is behind the hard work of project managers.
1, emergency funding issues
The project manager will encounter various complicated issues at the site:
Local residents of the project interfered with the project and there were many reports from the media. The contradiction between construction workers and foremen, the contradiction between suppliers and subcontractors, and even the occurrence of workers' strikes!
Photovoltaic power generation projects are generally located in remote areas. In case of urgent need for money in emergencies, it is not realistic to seek support again. Therefore, the construction site must require a certain amount of liquidity.
Proposal: On-site accounting staff is responsible for the management of project funds and project payments.
2, drawings, data management issues
Data management problems
The relationship between the contractor, the subcontractor, the supplier, and the various units is complex, and a large number of individuals are needed to sort out and summarize data and contacts. The lack of important information will lead to a slow progress. After the requirements and recommendations of the construction unit and the owner have been implemented, there will be no record, which may cause some negative impacts on the settlement of the subsequent projects.
Suggestion: Configure professional information staff, the company issued a data template or list to form a system.
Drawing speed is slow
The general project is the construction of the white edge, the blueprint is always lagging behind the construction, and even the construction based on the electronic version of the drawings appears. If the blueprint is inconsistent with the electronic version or the white image, let the design institute make changes. However, if there are a lot of design changes later on, there will be too many problems in acceptance.
The Design Institute has a large number of design tasks. Basically, which project is urging, the design of which project is to be done first. The general project will send someone to design at the design institute, and the drawing will be faster. However, when the special person is not in the design institute and returned to the department, the speed of drawing out will be slowed down immediately.
Suggestion: Specially arrange a colleague to urge the design institute to wait until the drawings are all finished before leaving.
There is no designation representative at the site
The design institute did not have a resident representative on the site. The problems in the drawings could not be solved in time. You need to write feedback. Then send an e-mail to the design institute. The design institute will then write a reply, then sign and seal, and then scan and send it back. It is very expensive. time. And no one stared at the Design Institute, and the Design Institute responded slowly.
Suggestion: When signing a contract with the Design Institute, add a request to set up a factory representative.
3, equipment supply problems
Deferred impact of goods on the scene
The arrival of goods at the project site is often unable to arrive on schedule, delaying the construction progress.
Suggestion: The supply company strictly controls the contract, and the contract should indicate the penalty method that does not arrive on time and strictly follows the contract.
Disputes between equipment manufacturers and logistics companies affect the speed of arrival
Equipment manufacturers rely on trusted logistics companies for shipping, but equipment manufacturers often have economic ties with logistics companies. This caused the equipment manufacturers to send the goods detained at the cargo station.
Suggestion: For the time being, no good solutions have been expected. Only manufacturers can be reminded.
Material cannot arrive on time
Material can not arrive on time, resulting in the phenomenon of labor.
Who bought the material?
The material at the scene sometimes finds out that it is not enough. At this time, secondary purchases are required, and secondary purchases are not clear, leading to mutual wrangling.
Proposal: Clear purchaser, issue written notice, purchase within a time limit.
4, the installation of the problem
Photovoltaic module related issues
1) Damage to the backplane: During the installation process, the backplane is often scratched, which can cause the backplane to seal loosely and enter the water vapor, which causes rapid power decay.
2) Tempered glass shatters: During handling and installation of components, tempered glass shatters, resulting in increased damage rate of component installation.
3) Component color difference: When installing, it is found that the components in each box will have serious color difference; if the color difference is larger, it will cause a larger matching loss.
Suggest:
1) Provide necessary training for workers and strictly implement the installation specifications. Workers are required to carry a component and treat the violators seriously.
2) Open the multi-tank assembly and put it into a piece. Pick a similar color and put it in a group.
Avoiding occlusion
Long-term occlusions can cause hot-spotting of components.
Vegetation: Considering the shade of the plant in the arrangement, whether the foliage causes obstruction
Corner occluding: The corner occluding is also present at the scene, but the number is not very large, and the general horn will be directly removed.
The difference in topography is obscured: The difference in terrain here must take into account whether the components are north-south or if the component objects cause shadows; the height of the subarrays in the same row is caused by the shadows; the shadows between the floors must also be considered.
Mud, bird droppings, dust, etc. Blocking: After the power station is built, mud, beak, dust, etc. will block the components, which requires regular inspection and cleaning.
Recommendation: Consider the topography difference in the design, taking into account the spacing of the array before and after the assembly. Periodically inspect the module array; clean and remove all kinds of fixed shields on the surface and surrounding of the module.
Cable specification bundle avoids hidden troubles
The cable specification binding seems to be a very small detail. In fact, it is the most important place that should not be neglected. Inverters, components, and combiner cables are not bundled and are easily detached when the wind blows, causing poor contact of the plug and causing a fire. Plug burned.
Suggestion: After the component substrings are debugged, tie the cables between the components. In the actual installation, pay attention to the construction quality and perfect the connection plugs. Introduce the convergence box cable to protect the pipes and mark them in the case.
Bracket problem
During the installation of the bracket, it often happens that the accuracy of the hole does not affect the installation of the bracket. As a result, the component mounting hole does not deviate from the mounting hole of the bracket. The screws cannot be installed. The construction personnel exert their creativity and some components of the frame are forced to move, and some are installed. Pad stones... These barbaric operations more or less affect the actual life of the components.
Recommendation: Avoid brute installation. Strictly requires the installation accuracy of the bracket; the elliptical long hole is reserved in the component mounting holes of the bracket beam; all the bolts of the bracket are loosened, and the overall adjustment makes the assembly neat.
Grounding is not beautiful
The general component grounding is to weld the flat iron from the bracket and access the main grounding net. Flat iron can not enter the ground along the cement, it is not very regular.
Suggestion: You can try to make the construction team enter the ground, first complete the grounding of the whole field, leaving a good margin, put the flat iron in the foundation.
Climatic conditions affect installation
1) The general power station project is located in the frontier winds and affects the welding.
Suggestion: Use earth to build the template for pouring, nail a cover, and weld in this cover to block the wind. But pay attention to fire prevention.
2) The spool is blown by the wind: When the cable is put, the spool is generally set up for the convenience of the cable, but the wind on Bohu side is large and it is easy to blow off the spool.
Suggestion: When the line is set up, when the work is finished, remember to remind the construction party to put the spool down.
Avoid basic weathering, stent corrosion
Because many power stations are located in a saline-alkaline environment, the quality of foundations for winter construction is poor, resulting in premature weathering of the concrete foundations; at the same time, the quality of galvanization in the stent production is poor, and bubbles or zincomas exist, affecting installation or corrosion.
Suggestion: Use hot-dip galvanized screws in the installation of components, install double flat cartridges; select well-known brands of brackets, pay special attention to the quality of hot-dip galvanizing in brackets; pay attention to the quality of concrete foundations in construction, and use basic surface coatings for saline and alkaline environments Brush waterproof asphalt and so on.
5, civil engineering issues
Cable trench problem
1) The cable trench in the confluence area on the drawing is passed through the assembly. If the construction is carried out according to the drawings, mechanical excavation can easily damage the components, artificial excavation, time-consuming and laborious, and delay the construction period.
Suggestion: The cable trenches beside the road, which saves manpower and speeds up the progress of the project.
2) The problem of using small red bricks and cable gutter brackets below ±0.00: If the 35kV foundation is built by the construction team, porous bricks shall be used for ±0.00 or less, and small red bricks shall be used for drawings. After communicating with the design, agreed to use porous bricks. However, when the cable bracket was later found, the bracket showed signs of shedding because the expansion bolts of the bracket entered the wall and entered the free space.
Suggestion: Use expansion bolts in the bracket to relieve the force of each expansion bolt. However, it is suggested that the construction must be done according to the plan next time.
Inverter room related problems
1) When the fire door of the inverter room is installed, some door holes are shaved to varying degrees.
Suggestion: When the owner himself measures, he should inform the fire door manufacturer that we are measuring the size of the door opening, the other party should set aside the installation allowance, or require the fire door manufacturer to directly measure the door opening.
2) The ladder outside the inverter room wall is reserved when masonry walls are built. However, the thickness of the thermal insulation plate was not taken into consideration at that time, resulting in the ladder being too tight from the thermal insulation plate and unable to get on.
3) The outdoor thermal insulation board of the inverter is then plastered. It feels like a wall. It is actually a thermal insulation board. This can lead to danger when people climb the ladder from the outside wall to the top of the inverter, climb to the end, and help the wall.
Suggest:
1) Remember to consider the thickness of the insulation board next time.
2) Add a ladder like a swimming pool.
Garbage is not cleaned up in time
The site's civil waste is not cleared in time, causing the construction waste to be cleaned up after installing the components.
Recommendation: Urge the civil construction team to clean up the garbage in time.
6. Cooperation with partners
1. Equipment manufacturers
Technician slow to field
Some factory technicians are slow to attend the meeting. Delayed installation and commissioning.
Suggestion: To make allowances for manufacturers' technical personnel to be present in advance. First, there is time for us to explain equipment and do training, and on the other hand, we will not delay installation and debugging.
On-site technical guidance
Some equipment manufacturers do not provide technical personnel for on-site guidance. There are problems with the equipment that need to be called up. Many problems communicate on the phone for a long time and the other person cannot accurately judge.
Suggestion: When signing a contract, pay attention to the requirements for equipment manufacturers to provide on-site instruction.
Technical Training
Some factory personnel came to the scene and would not go to the site without equipment problems. Ask them to do a training. They refuse to use the terms of the contract.
Suggestion: The contract adds the terms of the manufacturer to provide training. When approaching the venue, a security agreement should be signed, and before the charging equipment manufacturers enter the site, they should sign a security agreement and state in advance what conditions they will provide. For example, accommodation will only provide beds, do not provide bedding, and charge for meals.
2, construction team
Management System
Formulate a management system for the construction unit. When the construction unit enters the site, clearly notify the construction unit of its responsibilities and obligations in the project, make it comply with the rules established by the project department, and form a written version of the written agreement, in each construction When the unit enters the site, it should be signed and saved to comply with the rules set by the project department.
Coordination between different construction teams
The construction team and the construction team do not agree with each other. When the cable is laid, the cable trench is often dug to dig a part of the earthwork, causing the cable to be installed in the electrical appliance to be placed only for a period, and then it is necessary to stop.
Suggestion: The construction unit should come forward to open several theme conferences and coordinate all construction teams. The construction unit should have macro-control, and if necessary, it can give orders to each construction team.
7, common problems in operation and maintenance
Inspection
Safety management runs through the entire operation and maintenance process, including the rational use of safety tools and safety practices, etc. to ensure personal safety and equipment safety. Due to the limited experience of on-site operation skills and fault diagnosis and analysis, skilled personnel are required to train them. For high-voltage electrical parts, a high-voltage operation network license is also required before they can be certified.
Suggestion: Daily patrols, regular patrols and patrols under special circumstances are indispensable. They can grasp the operation status of the power station in time and find out existing or potential problems to ensure normal power generation.
Confluence box
The combiner box mainly focuses on the fuse burned (the fuse quality or the selected fuse rated current is too small), circuit breaker problems (such as fever, trip), communication abnormal (including the merger box collection module damage problem), terminal heating (terminal Looseness, excessive resistance, branch fault (ground fault, overcurrent), DC arcing, etc.
Inverter
The inverter is mainly concentrated in the failure of the module (mainboard) (usually caused by bad exhaust system, high cabinet temperature), over-temperature of the module (heating problem of the module itself), fan damage, burnout of the fuse, malfunction of the smoke detector, and open circuit Trip, start abnormality, ground fault, etc.
DC cable
DC cables are mainly concentrated in ground faults, damage to insulation skin (caused by construction or rolling of the vehicle), breakdown of cable heads, heating of cables (design and actual design of the design institute is not consistent, small diameters, heat will be difficult to avoid), short circuits, etc. Such as the construction of damaged skin, shallow depth of burial, in particular, some ground power station soil is gravel, if the depth of shallow cable, operation and maintenance vehicles through, it is easy to roll to the cable caused damage, need to operate in the inspection Timely discovery processing.
Suggestion: During the operation of photovoltaic power plant, faults may occur on both the DC and AC sides. For inverters, booster stations, and convergent cables, the frequency of faults is small. However, in the event of a fault, it will have a great impact on power generation. It can be seen from the real-time running status monitoring in the background. For DC side arrays, because of the large number of strings, faults are not easily found, and the frequency of the occurrence of failures is relatively high. The impact on power generation accounts for an important position. At the same time, there is also a certain amount of power generation that can improve the space. Requires operation and maintenance personnel to pay attention.
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