Description of the Software Modules and Parameters
Parameter manual b maXX BM3000
Document no.: 5.12001.07
727
of 820
4
4.11.3.2 Temperature model
The PU temperature model separately emulates and monitors the thermal load of the dif-
ferent device components on the basis of motor currents, the peak current time, the
mains- and DC link voltage as well as the thermal data of the semiconductors. The PU
temperature model is divided into two sub-models. The I
2
t-sub-model, which protects
conductors/capacitors and the power electronics sub-model, which protects the power
electronics.
Figure 225: Overload monitoring of the power unit (temperature model)
Correction factors and current derating
The maximum continuous current of the I
2
t-sub-model Z175.8– and also the maximum
continuous current of the device Z175.7– is emulated for the safety function "Current lim-
it" of the temperature model (as displayed in ZFig. 226–).
5000_0298_rev02_int.cdr
175.15
max(,)
..
t>
30s
105%
105%
95%
el
Lim
N
D
N
D
100
t>
30s
=0
=1
OR
100
LimPwmRed
LT-I2t-Ini
therm.
model
semicon-
ductors
Ist
N
D
PT1
N
D
I2t
max
Main voltage, 130.8, 141.12
dc link voltage, 130.3
Heat Sink temperature,
130.1,
Power electronic submodel
Iu, Iv, Iw actual values
47.32, 47.33, 47.34
Initialization
PU I2t max. continuous current actual value, 175.8
I2t submodel
Status PU temperature model
175.2 bit 4
Warning 206
Power unit
responded maximal
torque current limited
Current limited to
PU max. continuous current
actual value, 175.7, on
ThL-Act [%]
Status PU temperature model
175.2 bit 5
Mode
PU temperature model
175.1. bit 0
no PWM reduction
PWM reduction on
Warning 216
Power unit
responded
PWM reduced
Therm.
model
semi-
conductor
PU-I
2
t-Act [%]
Phase current Iu, Iv, Iw [A] 47.32, 47.33, 47.34
Voltage Udc [V] 130.3
Mains voltage [V
eff
] 130.8
PU heat sink temperature actual value (
ist
) [°C] 130.1
PU power electronic temperature actual value (
el
) [°C]
PU thermal load (ThL-Istwert) [%] 175.15
Output value of the I2t sub model (LT-I
2
t-Istwert) [%]
Temperature threshold as current limit (
lLim
) [°C]
Temperature threshold as PWM reduction (
Lim
) [°C]
PU time constant I
2
t model (
LT-I2t
) [s]
PU max. continuous current actual value [A
eff
] 175.7
PU I
2
t max. continuous current actual value [A
eff
] 175.8