SIEB & MEYER sinudyn-0360520 Series, Описание аппаратуры

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Electric Performance Dimensioning
:
86 Performance Dimensioning
Output performance
In practice, a maximum permanent power is specified for power supply units, since
the supply voltage is assumed to be constant. As the limitation in the power supply
unit is determined by the load carrying capacity of the diodes, the maximum perma-
nent power depends on the supply voltage and the type of supply.
Examples:
Power supply 230 V
AC
, 2 phases, max. permanent current of the diodes 6 A
230 V
AC
x 2 x 6 A = 2.76 kW
Power supply 400 V
AC
, 3 phases, max. permanent current of the diodes 6 A
400 V
AC
x 3 x 6 A = 7.20 kW
The maximum peak current depends on the type of diode used.
The protection is calculated as follows:
14.1.3 Motor
Among other things, the motor is specified by the following details:
Peak current
The peak current defines the maximum admissible motor current. The peak current
is only admissible for a short time (between 1 and 30 seconds) and depends on the
used magnetic material and the size of coil wire. The motor manufacturer generally
specifies the peak current for standstill and for the rotating field. In general, the spec-
ified values are r.m.s. values. Currents are indicated as sine crest values. In order to
get r.m.s. values, the sine crest value must be divided by .
Rated current
The rated current can permanently impressed to the motor. Its value depends on the
motor cooling, the coils and the maximum admissible motor temperature. The motor
manufacturer generally specifies the rated current for standstill and for the rotating
field. In general, the specified values are r.m.s. values. Currents are indicated as sine
crest values. In order to get r.m.s. values, the sine crest value must be divided by
.
Voltage constant
Due to the inductance of the motor, the motor generates a countervoltage during the
operation opposing the provided voltage. This voltage is proportional to the speed
and is specified in volt per 1,000 revolutions. In general, the specified values are
r.m.s. values and are measured between the connection terminals.
Example:
Intermediate circuit voltage: 325 V, e.m.f.: 100 mV min
-1
Only 225 V are provided at 1,000 RPM for controlling the motor. The theoretical max-
imum speed of the motor is 3,250 RPM. At this speed no torque is provided since no
current can be impressed anymore.
Performance
SupplyVoltage
----------------------------------------------
2 76kW ,
230V
AC
----------------------- 12A
eff
= =
2
2