ETAS ES5340.2, Руководство пользователя

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ES5340.2 Electric Drive Simulation Board - User’s Guide 50
FPGA Models ETAS
Inverter
The inverter has the following tasks:
• Generating AC voltage to operate the 3-phase electric motor from the DC
voltage of the battery (motor operation)
as well as:
• Generating DC voltage to charge the battery from the AC voltage of the
electric motor (generator mode, recuperation)
The inverter is controlled by the hybrid ECU according to the requirement of
torque or speed – depending on the driver command (accelerate, brake) and
battery charge level.
Specifically, this means (see Fig. 4-2):
• Measuring the position (
ϕ
) and speed (d
ϕ
/dt) of the electric motor
• Measuring the DC-link current (I
DC
), the DC-link voltage (U
DC
) and the
phase currents (I
U,V,W
, I
DC
) from/to the electric motor
and, as a result,
• Calculating the target voltages at the motor terminals
• and, in turn, calculating the switching phases of the switches in the
inverter branches
Fig. 4-2 Measurement and control variables of the inverter ECU
Synchronous Motor (PMSM)
The "PMSM" part of the model is used to simulate the phase currents and the
torque of the electric motor.
The PMSM is likewise configured via typical variables, such as the number of pole
pairs and cogging positions. Additional variables such as resistance, inductance,
the magnetic flow and the cogging torque can be changed during run time. For
the PMSM, the power loss of the ohmic components can also be simulated and
their temperature dependence can be calculated.
Mechanical System
For the mechanical connection to the drive train, the FPGA model also includes a
simulation of the spring-mass system. The system is configured with the typical
variables of coefficient of friction, moment of inertia for rotor and load, torsional
rigidity and damping. The load moment of the drive train can be preset and
changed during run-time.
I
UVW
, I
DC
, U
DC
ϕ, ϕ 
T
UH
, T
UL
, T
VH
T
VL
, T
WH
, T
WL