Danfoss VLT DriveMotor FCP 106, Руководство по конструкции

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130BA780.11
SYSTEM CURVE
FAN CURVE
PRESSURE %
A
B
C
0
20
40
60
80
100
120
20 40 60 80 100 120 140 160 180
VOLUME %
Illustration 4.5 The Graph Shows Fan Curves (A, B, and C) for
Reduced Fan Volumes
When using a frequency converter to reduce fan capacity
to 60%, more than 50% energy savings may be obtained in
typical applications.
120
100
80
60
40
20
0
20 40 60 80 100 120 140 160 180
120
100
80
60
40
20
0 20 40 60 80 100 120 140 160 180
Volume %
Volume %
INPUT POWER %
PRESSURE %
SYSTEM CURVE
FAN CURVE
A
B
C
130BA781.11
ENERGY
CONSUMED
Illustration 4.6 Energy Savings at Reduced Fan Capacity
4.2.3 Example of Energy Savings
As shown in Illustration 4.7 , the flow is controlled by
changing the RPM. By reducing the speed only 20% from
the rated speed, the flow is also reduced by 20%. This is
because the flow is directly proportional to the RPM. The
consumption of electricity, however, is reduced by 50%.
If a system only has to supply a flow that corresponds to
100% a few days in a year, while the average is below 80%
of the rated flow for the remainder of the year, the amount
of energy saved is even more than 50%.
Illustration 4.7 describes the dependence of flow, pressure,
and power consumption on RPM.
n
100%
50%
25%
12,5%
50% 100%
80%
80%
175HA208.10
Power ~n 3
Pressure ~n 2
Flow ~n
Illustration 4.7 Laws of Proportionality
Flow :
Q
1
Q
2
=
n
1
n
2
Pressure :
H
1
H
2
=
n
1
n
2
2
Power :
P
1
P
2
=
n
1
n
2
3
Q=Flow P=Power
Q
1
=Rated flow P
1
=Rated power
Q
2
=Reduced flow P
2
=Reduced power
H=Pressure n=Speed control
H
1
=Rated pressure n
1
=Rated speed
H
2
=Reduced pressure n
2
=Reduced speed
Table 4.1 Legend for Equation
4.2.4 Comparison of Energy Savings
The Danfoss frequency converter solution offers major
savings compared with traditional energy-saving solutions.
This is because the frequency converter is able to control
fan speed according to thermal load on the system and
the fact that the frequency converter has a built-in facility
that enables the frequency converter to function as a
building management system, BMS.
Illustration 4.8 shows typical energy savings obtainable
with 3 well-known solutions when fan volume is reduced,
Application Examples
VLT
®
DriveMotor FCP 106/FCM 106
50 Danfoss A/S © 06/2016 All rights reserved. MG03M202
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