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Semiconductor switches are very important and crucial components in
power
electronic
switches
are
meant
to
be
the
substitutions
of
the
mechanical
switches,but
they
are
severely
limited
by
the
properties
of the semiconductor materials and process of manufacturing.
在电力电
子系统，中半导体 开关是非常重要和关键部件。半导体开关将要替换机械开关
,
但半导体材料的性质和生产过程严 重限制了他们。
Switching losses
开关损耗
Power losses in the power eletronic converters are comprised of the
Switching losses and parasitic losses.
电力电子转换器的功率损耗分为开
关损耗和寄生损耗
the
parasitic
losses
account
for
the
losses
due
to
the
winding
resistances of the inductors and transformers,the dielectric losses of
capacitors,the eddy and the hysteresis losses.
寄生损失的绕组电感器、
变压器的阻力、介电损耗的电容器
,
涡流和磁滞损耗
the switching losses are significant and can be managed.
这个开关
损耗是非常重要的
,
可以被处理。
they can be further divided into three
components:(a)the
on-state
losses,(b)the
off-state
losses
and
the
losses
in
the
transition
states.
他们可以分为三个部分
:
通态损耗，断态损耗和转
换过程中产生的损耗。
On-State Losses
通态损耗
：
The
electrical
switches
conduct
heavy
current
and
have
nonzero
voltage
across
the
switch
in the
on-state
power
losses
are
given
by
Pon=Uson
if.
这个电子开关能导通 大电流，并且在通态时有非零的压降。这个通
态功率损耗的公式为
Pon=Uson if.
The Uson and If are respectively the switch voltage in the on-state
and
the
forward
current
through
the
example,the
typical
power
diodes and the power transistors have nearly 0.5 to l volt across them
in the forward currents can be hundreds to thousands of
on-state power losses are very significant.
其中
Uson
是通< br>态时开关上的压降，
if
是流过开关的电流。例如，典型的功率二极管和功率晶
体管有近似
0.5~1
伏的通态压降。
而电流会有数百到数千安培。
这个通态 损耗非
常重要。
Off-State Losses
断态损耗
The electrical switches withstand high voltages and have nonzero
leakage current through the switch in the off-state power
lesses
are
given
by
Poh=Uoff < br>ir
在关断状态时，电子开关到经受得起高电压，
并会有非零的漏电流。断态损耗的公式 为
Poh=Uoff ir.
The Usoff and Ir are respectively the reverse bias voltage in the
off-state and the reverse current through the example,the
typical
power
diodes
and
the
power
transistors
have
high
reverse
voltages
in
hundreds
to
thousands
of
volts
and
microamps
to
milliamps
through
them
in the off state.
其中< br>Uoff
在断态时的反向偏置电压，
ir
是流过开关的反向
漏电流。< br>例如，
典型的功率二极管和功率晶体管有很高的反向压降几百到几千伏
和几微安到几毫安 的漏电流。
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本文更新与2021-01-25 03:14，由作者提供，不代表本网站立场，转载请注明出处：https://www.bjmy2z.cn/gaokao/563766.html