Control Structures; Control Principle; Control Structure Open-Loop; Pm/Ec+ Motor Control - Danfoss VLT HVAC Basic Drive FC 101 Design Manual

Product Overview

2.7 Control Structures

2 2

2.7.1 Control Principle

1-00 Configuration Mode can be selected if open-loop or closed-loop is to be used.

2.7.2 Control Structure Open-loop

Reference
handling
Remote
reference
Auto mode
Hand mode
Local
reference
scaled to
Hz
LCP Hand on,
off and auto
on keys
Figure 2.17 Open-loop Structure
In the configuration shown in Figure 2.17, 1-00 Configuration Mode is set to [0] Open-loop. The resulting reference from the
reference handling system or the local reference is received and fed through the ramp limitation and speed limitation
before being sent to the motor control. The output from the motor control is then limited by the maximum frequency limit.

2.7.3 PM/EC+ Motor Control

The Danfoss EC+ concept provides the possibility for using high efficient PM motors (permanent magnet motors) in IEC
standard frame size operated by Danfoss adjustable frequency drives.
The commissioning procedure is comparable to the existing one for asynchronous (induction) motors by utilizing the
Danfoss VVC
Customer advantages:
•
Free choice of motor technology (permanent magnet or induction motor)
•
Installation and operation as known on induction motors
•
Manufacturer independent when selecting system components (e.g., motors)
•
Best system efficiency by selecting best components
•
Possible retrofit of existing installations
•
Power range: 45 kW (200 V), 0.37–90 kW (400 V), 90 kW (600 V) for induction motors and 0.37–22 kW (400 V) for
PM motors
26
Remote
Reference
Local
plus
PM control strategy.
Danfoss A/S © Rev. 2014-01-14 All rights reserved.
Design Guide
P 4-14
Motor speed
P 3-4* Ramp 1
high limit [Hz]
P 3-5* Ramp 2
Ramp
P 4-12
Motor speed
low limit [Hz]
100%
0%
To motor
control
100%
-100%
P 4-10
Motor speed
direction
MG18C522