Technical characteristics and application promotio

Technical characteristics and application promotion of digital central air conditioning system

Abstract: digital variable multi connected central air conditioning system is a new generation of modular multi connected system, which belongs to advanced air conditioning technology. Digital vortex technology can make the compressor operate in the range of 10% to 100% capacity, and realize stepless regulation in the whole range. The energy consumption is lower than the comprehensive energy consumption of variable frequency compressor, and there is no electromagnetic interference. The unit is highly intensive, There is no need to set up a machine room and no water. The simplicity and flexibility of its installation and maintenance make it more able to meet the needs of the air conditioning market. It is a technology worthy of promotion. This paper focuses on the characteristics and practical application of this technology

key words: digital air conditioning digital vortex pulse regulation cooling capacity attenuation electromagnetic interference

1 technical characteristics of digital central air conditioning system

digital (variable multi connection) central air conditioning system is composed of outdoor units of variable capacity vortex compressor with digital width pulse regulation control technology and multiple indoor units that can be controlled independently, referred to as DVM, which is a new generation of modular multi connection system, which is an advanced technology of air conditioning, The simplicity and flexibility of its installation and maintenance make it more able to meet the needs of the air conditioning market. The maximum pipe length of the unit is 100 meters, and the height difference can reach 50 meters. Because the unit is highly intensive and does not need to set up a machine room, it saves effective space for users. Compared with water-cooled units, there is no water system, which is both water-saving and convenient to maintain. The new digital central air-conditioning system can provide a wide range of air-conditioning methods for offices, apartments, shopping malls, hotels, hospitals, schools, factory workshops and other venues, as well as computer rooms, laboratories and other buildings of all sizes

the deformation of the width material completely disappears, but the overall profitability of the pulse regulated digital vortex is still low. The rotary compressor technology (PWM) can automatically adjust the cooling and heating capacity according to the load, so as to effectively reduce the operating cost. The essence of this technology is that the compressor itself has the characteristics of "axial flexibility". When the fixed scroll plate moves upward, the compressor's massless flow passes through. At this time, the compressor's capacity is zero and does not work on the refrigerant, that is, the "unloading state"; When the fixed scroll plate returns to its original position, it is the state when the ordinary scroll compressor is running. All the refrigerant passes through the compressor, and the compressor does work on the refrigerant. At this time, the compressor capacity is 100%, which is called "load state". The digital scroll compressor realizes the micro movement of the scroll plate (axial movement of 0.6 ~ 1mm) through the action and time of the precisely controlled PWM valve, so as to constantly change the lifting and meshing of the fixed scroll plate, that is, to change the cycle time of "load" and "unloading" to realize the adjustment of variable capacity. The external solenoid valve controls the "lifting" and "recovery" of the scroll plate through system signals according to the requirements of system capacity, Make the compressor automatically adjust the ratio of on-off time, realize "" output, reflect the digital function, and effectively reduce the operation cost

the transformation loss of digital scroll compressor from "load state" to "unloading state" is only 10%, which is lower than the comprehensive energy loss of variable frequency compressor. Moreover, digital scroll technology can make the compressor operate in the range of 10% to 100% capacity, realizing stepless regulation in the whole range, making the energy regulation range wider. In addition, the digital air conditioner also has the following characteristics: it can be flexibly combined according to the actual energy needs; The whole combined system adopts distributed control, and each unit adopts an independent refrigeration system, which can automatically adjust the load in different seasons and temperatures to ensure the operation in an energy-saving state; The stepless capacity output provided by digital vortex air conditioner ensures the control accuracy of room temperature at ± 0.5 ℃, which enables users to work in the most comfortable air conditioning environment. The room temperature of other types of air conditioners is controlled at ℃, which is very different from the comfort of the use environment of digital air conditioners. The digital scroll compressor operates at a single speed, so it will not produce additional noise and vibration, and will not cause adverse effects on the surrounding environment. The noise of indoor unit is very low, which is far lower than the national indoor noise standard; When the digital scroll compressor is running, the load unloading of the scroll plate is a simple mechanical movement, which does not produce high-order harmonics and electromagnetic interference; Digital vortex does not need oil separator or oil return circulation system. It uses the gas flow rate to fully flow the lubricating oil to the compressor, and will not burn the compressor due to poor oil return

2 technical comparison and analysis chart

Figure 1 Relationship between PWM valve and load

Figure 2 Comparison of refrigeration and heating performance/efficiency

Figure 3 Comparison of refrigeration capacity Figure 4 Comparison of power consumption

comparison of operating costs is shown in Table 1, and the consumption of energy consumption ratio is shown in Table 2. Operation cost comparison table 1

distinction

DVM

water cooler

VAV variable air volume system

energy consumption

44.2kw × 0.8

(Variable Compressor)

43kw × 1.0

52.5kw × 1.0

monthly consumption

12906 kW

15695 kW

19162 kW

half year consumption (6 months)

77436 kW

94170 kW

114972 kW

1-year consumption

5575

6780

8277

3-year consumption

16726

20340

24833

5-year consumption

27877

33900

.389

comparison results

100%

121% ↑

148% ↑

note: the test conditions of the above data are as follows: the building area is 750 ㎡, the load is 7740kw, and the winter and summer are operated for three months respectively

calculation table of energy consumption ratio 2

control area

test conditions

VAV

DVM

load rate

performance w

Power W

energy consumption ratio

load rate

performance w

Power W

energy consumption ratio

P> 25%