User`s manual

DS2100 User’s Manual SECTION 7: CANOPEN DRIVE PROFILE: DS402
PAGE 7-64 C27750-001
7.19 Velocity Control Function
The DS402 standard defines a number of parameters related to velocity, which are particularly relevant when in
velocity mode. In addition it also defines a windowing function that is used to determine if a target velocity has
been reached, or if the actual velocity is below a certain threshold value. Parameters for configuration and tuning of
the velocity loop are manufacturer specific. The DS402 parameters that are defined are listed below: -
Figure 7.33 Velocity control function
Index Name Type Comment
0x6069 ds402 velocity sensor actual value S32 Value read from resolver in (incs/sec)
0x606B ds402 velocity demand value S32 Output of velocity demand function, in
velocity units.
0x606C ds402 velocity actual value S32 Sensor Value scaled to be in velocity units
0x606D ds402 velocity window U16 Limits (in velocity units) within which
target velocity reached bit can be set, in
status word.
0x606F ds402 velocity threshold U16 If velocity actual value is less than or equal
to this value (in velocity units), Speed=0 bit
can be set, in status word.
Table 7.25 Table of velocity control function parameters
In addition a velocity control parameter set has been defined. It is a grouping of existing drive parameters, into a
single ds402 record, (under parameter number 0x60F9). This record is included in the velocity control table of
parameters on the following page.
GENERAL ISSUES
1. Velocity Window and Velocity Threshold are only used in velocity modes.
2. The Velocity Sensor Actual Value, is derived from the velocity in units of incs/Tsamp, and includes the
negation of the Velocity Polarity Bit, if the bit is set.
3. The velocity window and velocity threshold functions do not implement a window time. There is no
duration for which the actual velocity must be within the window, before the target reached bit is set in the
status word. Instead if the actual velocity is within the window, the target reached bit is set. Similarly if the
actual velocity is less than the threshold, the Speed=0 bit is set and there is no duration involved.
Homing
Function
Velocity
Control Loop
Demand
Generation
Velocity Demand Value
Velocity Sensor Actual Value
Velocity Sensor
Actual Value
Velocity Window
Vel. Enc Factor + Polarity
Velocity Threshold
Velocity Actual Value
Vel. Enc Factor + Polarity