Rise time

The rise time is the period which elapses between an abrupt change in a setpoint and the moment the actual value first reaches the tolerance band (2 %) around the setpoint.
The dead time is the period which elapses between the abrupt change in the setpoint and the moment the actual value begins to increase. The dead time is partially determined by the read-in, processing and output cycles of the digital closed-loop control. Where the dead time constitutes a significant proportion of the rise time, it must be separately identified.

Characteristic angular frequency -3 dB

The limit frequency is a measure of the dynamic response of a closed-loop control. A pure sinusoidal setpoint is input to calculate the limit frequency; no part of the control loop must reach the limit. The actual value is measured under steady-state conditions and the ratio between the amplitudes of actual value and setpoint is recorded.
-3 dB limit frequency: Frequency at which the absolute value of the actual value drops by 3 dB (to 71 %) for the first time. The closed-loop control can manage frequencies up to this value and remain stable.

Ripple

The ripple is the undesirable characteristic of the actual value which is superimposed on the mean value (useful signal). Oscillating torque is another term used in relation to torque. Typical oscillating torques are caused by motor slot grids, by limited encoder resolution or by the limited resolution of the voltage control of the IGBT power unit. The torque ripple is also reflected in the speed ripple as being indirectly proportional to the mass inertia of the drive.

Accuracy

Accuracy is a measure of the magnitude of the average, repeatable deviation between the actual value and setpoint under nominal conditions. Deviations between the actual value and setpoint are caused by internal inaccuracies in the measuring and control systems. External disturbances, such as temperature or speed, are not included in the accuracy assessment. The closed-loop and open-loop controls should be optimized with respect to the relevant variable.

Typical application

• Drives with highly dynamic motion control
• Angular-locked synchronism with isochronous PROFIBUS/PROFINET in conjunction with SIMOTION
• For use in machine tools and clocked production machines

• Speed-controlled drives with high speed and torque stability in general mechanical engineering systems
• Particularly suitable for asynchronous motors

• Drives with low requirements on dynamic response and accuracy
• Highly synchronized group drives, e.g. on textile machines with SIEMOSYN motors

Mixed operation of Servo Control and Vector Control is not possible on CU320?2. Mixed operation with V/f control modes is possible.

Dynamic response

Very high

High

Low

Highest dynamic response with 1FK7 High Dynamic synchronous motors and Servo Control.

Control modes with encoder

Position control/
Speed control/
Torque control

Position control/
Speed control/
Torque control

None

SIMOTION D with Servo Control is standard for motion control.

Control modes without encoder

Speed control

Speed control/
Torque control

All V/f control modes

With Servo for asynchronous motors only.
With V/f control the speed can be kept constant by means of selectable slip compensation.

Asynchronous motor

Synchronous motor

Torque motor

Linear motor

Yes

Yes

Yes

Yes

Yes

No

Yes

No

Yes

No

No

No

V/f control (textiles) is recommended for SIEMOSYN motors.

Permissible ratio of motor rated current to rated current of Motor Module

1:1 to 1:4

1.3:1 to 1:4

1:1 to 1:12

Maximum control quality in the case of Servo Control and Vector Control up to 1:4. Between 1:4 and 1:8 increasing restrictions as regards torque and rotational accuracy. V/f Control is recommended for < 1:8.

Maximum number of parallel-connected motors per Motor Module

4

8

Unlimited in theory

Motors connected in parallel must be asynchronous (induction) motors with identical power ratings.
With V/f Control, the motors can have different power ratings.

Setpoint resolution position controller

31 bit + sign

31 bit + sign

–

Setpoint resolution speed/frequency

31 bit + sign

31 bit + sign

0.001 Hz

Setpoint resolution torque

31 bit + sign

31 bit + sign

–

Maximum output frequency

• For current controller clock cycle/
  pulse frequency

660 Hz
at 125 ?s/4 kHz

330 Hz
at 250 ?s/4 kHz

400 Hz
at 250 ?s/4 kHz

Note limit voltage (2 kV) and use of VPM Module with synchronous motors.

For asynchronous motors only:
When using edge modulation, 600 Hz are possible at 4 kHz, or 300 Hz at 2 kHz and 200 Hz at 1.25 kHz.

• With current controller clock cycle/pulse frequency (chassis frame sizes FX and GX)

330 Hz
at 250 ?s/2 kHz

160 Hz
at 250 ?s/2 kHz

200 Hz
at 250 ?s/2 kHz

• For current controller clock cycle/
  pulse frequency
  (chassis frame sizes HX and JX)

Not permitted

100 Hz
with 400 ?s/1.25 kHz

100 Hz
with 400 ?s/1.25 kHz

Maximum field weakening

• For asynchronous motors

5 x

5 x

4 x

With Servo Control combined with encoder and appropriate special motors, field weakening up to 16 times the field-weakening threshold speed is possible.

• For synchronous motors

2 x

2 x

–

These values refer to 1FT7/1FK7 synchronous motors.
Note limit voltage (kE factor) with non-Siemens motors.

Synchronous motor

1FK7 with R14DQ ¹⁾

1FT7

Vector Control is not designed as an operating mode for 1FK7/1FT7 synchronous motors.

Controller cycle

125 ?s

125 ?s

Rise time (without delay)

0.7 ms

0.5 ms

At a speed operating range from 50 rpm for resolver.

Characteristic angular frequency -3 dB

650 Hz

900 Hz

In this case, the dynamic response is determined primarily by the encoder system.

Torque ripple

3 % of M₀

0.6 % of M₀

With speed operating range of 20 rpm up to rated speed.
A ripple of < 1 % is possible with an absolute encoder ? 1 rpm.
Not possible with resolver.

Torque accuracy

± 1.5 % of M₀

± 1.5 % of M₀

Measured value averaged over 3 s.
With motor identification and friction compensation.
In torque operating range up to ± M₀.
Speed operating range 1:10 up to rated speed.
Caution: External influences such as motor temperature can cause an additional long-time inaccuracy (constancy) of about ± 2.5 %.
Approx. ± 1 % less accuracy in field-weakening range.

Asynchronous motor

1PH8 without encoder

1PH8 with incremental encoder 1024 S/R

1PH8 without encoder

1PH8 with incremental encoder 1024 S/R

Controller cycle

125 ?s

125 ?s

250 ?s

250 ?s

Total rise time (without delay)

–

0.8 ms

2 ms

1.2 ms

With encoderless operation in speed operating range 1:10, with encoder 50 rpm and above up to rated speed.

Characteristic angular frequency -3 dB

–

600 Hz

250 Hz

400 Hz

With encoderless operation in speed operating range 1:10.
The dynamic response is enhanced by an encoder feedback.

Torque ripple

–

1.5 % of M_rated

2 % of M_rated

2 % of M_rated

With encoderless operation in speed operating range 1:20, with encoder 20 rpm and above up to rated speed.

Torque accuracy

–

± 3.5 % of M_rated

± 2 % of M_rated

± 1.5 % of M_rated

Measured value averaged over 3 s.
With motor identification and friction compensation, temperature effects compensated by KTY84 and mass model.
In torque operating range up to ± M_rated.
Approx. additional inaccuracy of ± 2.5 % in field-weakening range.
Servo: Speed operating range 1:10 referred to rated speed.
Vector: Speed operating range 1:50 referred to rated speed.

Synchronous motor

1FK7 with R14DQ ¹⁾

1FT7

Vector Control is not designed as an operating mode for 1FK7/1FT7 synchronous motors.

Controller cycle

125 ?s

125 ?s

Total rise time (without delay)

3.5 ms

2.3 ms

With encoderless operation in speed operating range 1:10, with encoder 50 rpm and above up to rated speed.

Characteristic angular frequency -3 dB

140 Hz

250 Hz

In this case, the dynamic response is determined primarily by the encoder system.

Speed ripple

See note

See note

Determined primarily by the total mass moment of inertia, the torque ripple and especially the mechanical configuration.
It is therefore not possible to specify a generally applicable value.

Speed accuracy

? 0.001 % of n_rated

? 0.001 % of n_rated

Determined primarily by the resolution of the control deviation and encoder evaluation in the converter. This is implemented on a 32?bit basis for SINAMICS.

Asynchronous motor

1PH8 without encoder

1PH8 with incremental encoder 1024 S/R

1PH8 without encoder

1PH8 with incremental encoder 1024 S/R

Controller cycle

125 ?s

125 ?s

250 ?s

250 ?s

Total rise time (without delay)

12 ms

5 ms

20 ms

10 ms

With encoderless operation in speed operating range 1:10, with encoder 50 rpm and above up to rated speed.

Characteristic angular frequency -3 dB

40 Hz

120 Hz

50 Hz

80 Hz

With encoderless operation in speed operating range 1:10.
The dynamic response is enhanced by an encoder feedback.
Servo with encoder is slightly more favorable than Vector with encoder, as the speed controller cycle with Servo is quicker.

Speed ripple

See note

See note

See note

See note

Determined primarily by the total mass moment of inertia, the torque ripple and especially the mechanical configuration.
It is therefore not possible to specify a generally applicable value.

Speed accuracy

0.1 ? f_slip

? 0.001 % of n_rated

0.05 ? f_slip

? 0.001 % of n_rated

Without encoder: Determined primarily by the accuracy of the calculation model for the torque-producing current and rated slip of the asynchronous motor (see table "Typical slip values").
With speed operating range 1:50 (Vector) or 1:10 (Servo) and with activated temperature evaluation.

Synchronous motor

1FT7

1FK7

Vector Control is not designed as an operating mode for 1FT7/1FK7 synchronous motors.

Position controller cycle

1 ms

1 ms

Resolution

4.19 ? 10⁶
incr./rev.

16384
incr./rev.

Correspondingly better with multi-pole resolver.

Attainable positioning accuracy

10⁵ ... 10⁶
incr./rev.

4096
incr./rev.

In practice, the resolution must be higher than the required positioning accuracy by a factor of 4 to 10. These values are approximate nominal values only.

• In relation to the motor shaft, approx.

0.00072 °

0.1 °

Asynchronous motor

1PH8 with AM22DQ ¹⁾

1PH8 with incremental encoder 1024 S/R

1PH8 with AM22DQ ¹⁾

1PH8 with incremental encoder 1024 S/R

Position controller cycle

1 ms

1 ms

2 ms

2 ms

Resolution

4.19 ? 10⁶
incr./rev.

4096
incr./rev.

4.19 ? 10⁶
incr./rev.

4096
incr./rev.

Attainable positioning accuracy

10⁵ ... 10⁶
incr./rev.

1024
incr./rev.

10⁵ ... 10⁶
incr./rev.

512
incr./rev.

In practice, the resolution must be higher than the required positioning accuracy by a factor of 4 to 10. These values are approximate nominal values only.
Vector is less accurate than Servo by a factor of approximately 2.

• In relation to the motor shaft, approx.

0.00072 °

0.35 °

0.00072 °

0.7 °

Synchronous motor

1FT7
without encoder

1FT7 with AM22DQ ¹⁾

Vector Control is not designed as an operating mode for 1FT7 synchronous motors.

Controller cycle

250 ?s

250 ?s

Total rise time (without delay)

–

1.2 ms

Characteristic angular frequency -3 dB

–

400 Hz

In this case, the dynamic response is determined primarily by the encoder system.

Torque ripple

–

1.3 % of M₀

A ripple of < 1 % is possible with an absolute encoder ? 1 rpm.
Not possible with resolver.

Torque accuracy

–

± 1.5 % of M₀

Measured value averaged over 3 s.
With motor identification and friction compensation. In torque operating range up to ± M₀.
Speed operating range 1:10 up to rated speed.
Caution: External influences such as motor temperature can cause an additional long-time inaccuracy (constancy) of about ± 2.5 %.
Approx. ± 1 % less accuracy in field-weakening range.

Asynchronous motor

1PH8 without encoder

1PH8 with incremental encoder 1024 S/R

1PH8 without encoder

1PH8 with incremental encoder 1024 S/R

Controller cycle

250 ?s

250 ?s

250 ?s

250 ?s

Total rise time (without delay)

–

1.6 ms

2.5 ms

1.6 ms

With encoderless operation in speed operating range 1:10, with encoder 50 rpm and above up to rated speed.

Characteristic angular frequency -3 dB

–

350 Hz

200 Hz

300 Hz

With encoderless operation in speed operating range 1:10.
The dynamic response is enhanced by an encoder feedback.

Torque ripple

–

2 % of M_rated

2.5 % of M_rated

2 % of M_rated

With encoderless operation in speed operating range 1:20, with encoder 20 rpm and above up to rated speed.

Torque accuracy

–

± 3.5 % of M_rated

± 2 % of M_rated

± 1.5 % of M_rated

Measured value averaged over 3 s.
With motor identification and friction compensation, temperature effects compensated by KTY84 and mass model.
In torque operating range up to ± M_rated. Approx. additional inaccuracy of ± 2.5 % in field-weakening range.
Servo: Speed operating range 1:10 referred to rated speed.
Vector: Speed operating range 1:50 referred to rated speed.

Synchronous motor

1FT7 without encoder

1FT7 with AM22DQ ¹⁾

Vector Control is not designed as an operating mode for 1FT7 synchronous motors.

Controller cycle

250 ?s

250 ?s

Total rise time (without delay)

–

5 ms

With encoderless operation in speed operating range 1:10, with encoder 50 rpm and above up to rated speed.

Characteristic angular frequency -3 dB

–

100 Hz

In this case, the dynamic response is determined primarily by the encoder system.

Speed ripple

–

See note

Determined primarily by the total mass moment of inertia, the torque ripple and especially the mechanical configuration.
It is therefore not possible to specify a generally applicable value.

Speed accuracy

–

? 0.001 % of n_rated

Determined primarily by the resolution of the control deviation and encoder evaluation in the converter.
This is implemented on a 32?bit basis for SINAMICS.

Asynchronous motor

1PH8 without encoder

1PH8 with incremental encoder 1024 S/R

1PH8 without encoder

1PH8 with incremental encoder 1024 S/R

Controller cycle

250 ?s

250 ?s

250 ?s

250 ?s

Total rise time (without delay)

21 ms

8 ms

20 ms

12 ms

With encoderless operation in speed operating range 1:10, with encoder 50 rpm and above up to rated speed.

Characteristic angular frequency -3 dB

25 Hz

80 Hz

35 Hz

60 Hz

With encoderless operation in speed operating range 1:10. The dynamic response is enhanced by an encoder feedback. Servo with encoder is slightly more favorable than Vector with encoder, as the speed controller cycle with Servo is quicker.

Speed ripple

See note

See note

See note

See note

Determined primarily by the total mass moment of inertia, the torque ripple and especially the mechanical configuration.
It is therefore not possible to specify a generally applicable value.

Speed accuracy

0.1 ? f_slip

? 0.001 % of n_rated

0.05 ? f_slip

? 0.001 % of n_rated

Without encoder: Determined primarily by the accuracy of the calculation model for the torque-producing current and rated slip of the asynchronous motor (see table "Typical slip values").
With speed operating range 1: 50 (Vector) or 1:10 (Servo) and with active temperature evaluation.

< 1 kW

6 % of n_rated
e.g. motor with 1500 rpm: 90 rpm

The slip values of 1PH asynchronous motors are very similar to those of standard motors

< 10 kW

3 % of n_rated
e.g. motor with 1500 rpm: 45 rpm

< 30 kW

2 % of n_rated
e.g. motor with 1500 rpm: 30 rpm

< 100 kW

1 % of n_rated
e.g. motor with 1500 rpm: 15 rpm

> 500 kW

0.5 % of n_rated
e.g. motor with 1500 rpm: 7.5 rpm

Servo Control

62.5 ?s

3

3

3 servo axes are possible with a cycle time of 62.5 ?s.
The performance expansion is therefore ineffective.

The performance expansion is required with 4 or more servo axes irrespective of computing capacity.

125 ?s

3

6

250 ?s

3

6

Vector Control

250 ?s

3

3

3 servo axes are possible with a cycle time of 250 ?s.
The performance expansion is therefore ineffective.

The performance expansion is required with 4 or more vector axes irrespective of computing capacity.

500 ?s

3

6

V/f Control

250 ?s

6

6

6 V/f axes are possible with a cycle time of 250 ?s.
The performance expansion is therefore ineffective.

The performance expansion is required with 7 or more V/f axes irrespective of computing capacity.

500 ?s

6

12

Mixed operation

Servo Control plus V/f Control

125 ?s/500 ?s

3+0; 2+2; 1+4; 0+6

6+0; 5+2; 4+4; 3+6
2+8; 1+10; 0+12

Two V/f axes can be computed instead of a servo or vector axis.

Vector Control plus V/f Control

500 ?s/500 ?s

3+0, 2+2; 1+4; 0+6

6+0; 5+2; 4+4; 3+6
2+8; 1+10; 0+12

Servo Control, Vector Control

(required max. output frequency/speed)

100 Hz correspond to:

3000 rpm for Z_p = 2
1500 rpm for Z_p = 4
428 rpm for Z_p = 14
352 rpm for Z_p = 17

1.25 kHz

Z_p is the number of pole pairs of the motor.

This equals 2 on 1PH asynchronous motors.
1FT7/1FK7 synchronous motors have between 3 and 5 pairs of poles.
For torque motors, the numbers of pole pairs are typically 14 and 17.

When edge modulation is used (only possible for asynchronous motors), the output frequency is increased by a factor of 2.

160 Hz correspond to:

4800 rpm for Z_p = 2
2400 rpm for Z_p = 4
685 rpm for Z_p = 14
565 rpm for Z_p = 17

2 kHz

200 Hz correspond to:

6000 rpm for Z_p = 2
3000 rpm for Z_p = 4
856 rpm for Z_p = 14
704 rpm for Z_p = 17

2.5 kHz

300 Hz correspond to:

9000 rpm for Z_p = 2
4500 rpm for Z_p = 4
1284 rpm for Z_p = 14
1056 rpm for Z_p = 17

4 kHz

400 Hz correspond to:

12000 rpm for Z_p = 2
6000 rpm for Z_p = 4

4 kHz

Caution: For Servo Control with 1FT7/1FK7 motors only.
Note field weakening requirements and suitable encoder system for higher speeds.

V/f Control

(required max. output frequency/speed)

100 Hz correspond to:

6000 rpm for Z_p = 1
3000 rpm for Z_p = 2

1.25 kHz

V/f Control is designed only for asynchronous motors and SIEMOSYN motors.

Z_p is the number of pole pairs of the motor.

This is mainly between 1 and4 on 1LA/1LG standard asynchronous motors.
SIEMOSYN motors have 1 or 2 pole pairs or, with larger shaft heights, 3 pairs.

160 Hz correspond to:

9600 rpm for Z_p = 1
4800 rpm for Z_p = 2

2 kHz

200 Hz correspond to:

12000 rpm for Z_p = 1
6000 rpm for Z_p = 2

2.5 kHz

300 Hz correspond to:

18000 rpm for Z_p = 1
9000 rpm for Z_p = 2

4 kHz

400 Hz correspond to:

24000 rpm for Z_p = 1
12000 rpm for Z_p = 2

4 kHz

Dynamic response requirement (current controller clock cycle)

125 ?s
250 ?s
400 ?s
500 ?s

4 kHz
2 kHz
2.5 kHz
1 kHz

Servo Control requires a minimum pulse frequency of 2 kHz.

Sine-wave filters

–

4 kHz

Caution: If sine-wave filters are operated at low pulse frequencies, resonance problems can occur and cause the filters to severely overheat.

Output reactor to motor

Max. frequency: 150 Hz correspond to 4500 rpm for Z_p= 2

The output reactor can be operated at minimum 2 kHz only.