How building automation system plays its role in intelligent building and its benefit analysis

First, give full play to the functions of mechanical and electrical equipment to ensure the safe and stable operation of mechanical and electrical equipment.

Intelligent buildings are generally equipped with various air-conditioning equipment, aiming at creating a comfortable working and living environment for buildings. However, if the building automation system is not adopted, the indoor temperature and humidity cannot be manually adjusted at any time. With the change of indoor personnel and outdoor temperature and humidity, it will inevitably lead to the phenomenon that the room temperature is too cold (below the standard set value) or too hot (above the standard set value), and the humidity is too high (above the standard set value) or too low (below the standard set value). The building automatic control system can not only automatically adjust the indoor temperature and humidity according to the setting, but also change the indoor temperature setting according to the outdoor temperature and humidity and seasonal changes, so as to meet people's needs and give full play to the functions of air conditioning equipment.

Similarly, from the health point of view, everyone in the building must ensure a certain fresh air volume, and the standard of fresh air volume should be determined according to the allowable indoor CO2 concentration, which is generally 0. 1%( 1000ppm). It is inaccurate to fix the fresh air volume, because with the change of season and time, the change of air pollution and the change of CO2 concentration in outdoor air, the demand for fresh air volume naturally changes with the change of indoor personnel. Therefore, the most reasonable way is to automatically adjust the fresh air volume according to the CO2 concentration in the indoor or return air to ensure the freshness of indoor air, which requires a building automatic control system with perfect control functions to complete these control requirements.

The use of building automation system can also effectively and accurately control other mechanical and electrical equipment in the building, so that these mechanical and electrical equipment can operate under more reasonable conditions, play their role more effectively, and ensure and improve the investment benefit accounting for a considerable proportion of the whole building investment.

Building automatic control system can monitor the running state and parameters of electromechanical equipment in the building in real time. For motor-driven equipment such as fans and water pumps, it is possible to judge whether the motor has short circuit and overload faults by monitoring the auxiliary contacts of circuit breakers and thermal relays. At the same time, it is also possible to judge whether the fan and the water pump have mechanical failure by detecting the state of the airflow switch and the water flow switch. Similarly, the building automatic control system can detect the parameters that reflect the normal operation of the equipment, such as filter screen blockage, water level of water tank, transformer temperature, elevator operation position and so on. When these electromechanical devices fail, the building automatic control system can report the location, cause and type of the failure in time, so that maintenance personnel can quickly rush to the scene to eliminate the failure, restore the normal operation of the equipment, avoid further expansion of the failure, ensure the safety of equipment and personnel, improve the overall safety level of the building, and thus protect the investment of the equipment. Second, save a lot of operation and management personnel and improve the equipment management level in an all-round way.

There are many kinds of electromechanical equipment in intelligent buildings, from underground pumps to cooling towers on the roof, which are distributed in every corner of the building. It is almost impossible to manually switch and adjust these devices. Even if the traditional instrument control can partially solve the adjustment problem, a large number of operation managers still need to switch and control the equipment on each floor upstairs and downstairs and set parameters. The workload is enormous. In this case, it will be more difficult to realize effective equipment management, organize and store equipment files, and record and analyze equipment operation.

After adopting the building automation system, the above-mentioned switching and adjustment control work can be completed in the central control room through the keyboard or mouse of the computer in the operation station, and the parameters and switching state of each equipment are automatically controlled and adjusted by the software in the computer according to the set program, thus realizing real management automation, thus reducing the labor intensity of managers and reducing the number of managers.

On the other hand, when the on-off state and operation parameters of the equipment in the building are abnormal, such as the temperature and humidity in some areas exceed the set values, the building automatic control system can also report to the management personnel in time, so that the management personnel can quickly rush to the scene for treatment, or carry out maintenance or adopt a backup plan, promptly eliminate equipment failures, restore the comfort of the environment as soon as possible, avoid user complaints, and improve the service level of property management.

The use of building automation system can comprehensively improve the level of equipment management, which is embodied in the following aspects:

1. Original documents of origin, model and specification of all mechanical and electrical equipment; And the cumulative running time and maintenance of the equipment; For reference during maintenance. At the same time, the printed maintenance report is automatically generated according to the maintenance regulations, prompting managers to maintain the equipment to avoid early or delayed maintenance, so that the electromechanical equipment is always in the best operation state under the unified management of the building automation system, and the service life of the electromechanical equipment is correspondingly prolonged.

2. Collect, calculate and store the operation parameters and open state of electromechanical equipment, and display and print them in the form of dynamic simulation diagram, various real-time or historical reports and trend diagrams. As a manager, equipment management analysis and decision-making make equipment management more reliable and accurate.

3. According to the different positions of managers, different operating rights are given, and different levels of passwords are assigned to each manager. When dealing with various operations and faults, record the password of the manager who indicates his identity and the name and time of the corresponding user for future reference. Improve the sense of responsibility of managers.

Second, save the energy consumption of mechanical and electrical equipment and reduce the operating cost of mechanical and electrical equipment.

Building automatic control system can not only improve the function of mechanical and electrical equipment, but also reduce the management and operation personnel; More importantly, using building automation system and adopting a series of corresponding energy-saving management measures can effectively save energy consumption and reduce operating costs. This is also the most important means to invest in the recovery benefit of building automation system. Specifically, there can be the following aspects:

1. Measure the parameters of each energy consumption point in the building.

It is an important means of energy saving to measure and measure the parameters of each energy point in the building and combine them with the charge. When users know that their energy consumption is metered and charged, energy consumption will be greatly reduced. However, it is very difficult to copy, classify, accumulate, calculate and charge these parameters by traditional manual methods, and it cannot be completed in time. This kind of work will be more troublesome when users change frequently. It is easier to solve these problems by using building automation system, which can be completed automatically. The building automation system can automatically print out a report every month, listing the energy consumption, unit price and accounts receivable of each user. In fact, building automation system can also provide users with energy consumption distribution curve, so that users can identify the time of peak load and evaluate various measures to reduce energy consumption on this basis.

2. Improve the control accuracy of the controlled parameters.

The change of temperature and humidity in buildings is closely related to building energy conservation. According to the statistics of the National Bureau of Standards, if the set temperature in summer is reduced by 1℃, the energy consumption will increase by 9%. If the set temperature in winter increases by 1℃, the energy consumption will increase by 12%. Therefore, it is an effective measure to control the temperature and humidity in the building within the precision range of the set value. Without automatic control or using traditional automatic control methods, it is impossible to change the set value according to the outdoor environment and seasonal changes, and often the room temperature is too cold in summer or too hot in winter. This over-cooled and over-heated temperature phenomenon is not only inappropriate for human health and comfort, but also wastes energy. Therefore, it can be said that the higher the temperature and humidity control accuracy of air conditioning system, the better the comfort and the more obvious the energy-saving effect.

As mentioned above, in order to maintain the health of people in the building, it is necessary to ensure a certain amount of fresh air, but too much fresh air will increase energy consumption. Generally speaking, under the design conditions (room temperature 26℃ in summer, relative humidity 60%; Under the condition of room temperature of 22℃ and relative humidity of 55% in winter, it takes 6.5kwh of cold energy and 12.7kwh of heat to treat one kilogram of outdoor fresh air. Therefore, under the premise of meeting the indoor hygiene requirements, reducing the fresh air volume has obvious energy-saving effect.

3. Optimal start-stop control of electromechanical equipment

For offices, shopping malls and other buildings, air conditioning is not needed at night. You don't have to turn on the air conditioner at night. In order to ensure the comfort of the indoor environment in the early stage of work, it is necessary to precool and preheat the building in advance. In addition, the indoor temperature is a controlled object with great inertia. Turning off the air conditioner in advance can also ensure that the indoor temperature will not change much in a certain period of time. Building automatic control system can shorten the unnecessary tolerance time of air conditioning start-stop on the premise of ensuring comfortable environment. At the same time, when pre-cooling and pre-heating, closing the outdoor fresh air valve can not only reduce the equipment capacity, but also reduce the energy consumption of refrigeration or heating caused by obtaining fresh air.

In commercial buildings, lighting electricity consumption accounts for a large part of the total electricity consumption, among which public lighting is the most likely to produce energy waste. The power consumption can be greatly reduced by controlling the lighting equipment to turn off regularly, or even by pre-dimming control and window dimming control according to the timetable and outdoor light.

In areas where multiple electricity prices are implemented, building automatic control system, together with ice hockey cold storage equipment and emergency generators, can choose to cut off some relatively unimportant electromechanical equipment to reduce peak load, or put emergency generators into operation during peak power consumption to release stored cold energy, realize off-peak operation and reduce operating costs.

4. Cleaning and quantity control

Indoor air is a controlled object with great inertia. After calculating how long the air conditioner can stop, on the premise of ensuring the comfort of the air conditioning area, determine the start and stop time of the air conditioner in each cycle, and start and stop the air conditioner at intervals to save energy. The start-stop time interval of air conditioner can be selected according to indoor and outdoor environment and seasonal changes.

The air conditioning and refrigeration system is designed according to the maximum load, but in the actual operation process, the load is constantly changing. According to the load change, the energy consumption of cold source equipment can be greatly reduced by controlling the number of cooling towers, cooling pumps, freezing pumps and freezers.

Building automatic control system can organically connect all the mechanical and electrical equipment in the building, integrate these mechanical and electrical equipment into a unified system, and realize information sharing, so as to comprehensively control and manage the mechanical and electrical equipment, which cannot be achieved by manual and traditional control methods, and its function and benefit are enormous. To realize these functions and benefits, we must first give play to the role of building automation system.