Interface circuit with power converter with interface circuit and electric vehicle with power converter

An interface circuit for transferring a control signal from a small-signal circuit to a power transistor, for driving said power transistor, said interface circuit comprising a noise absorber for electrically absorbing noise voltage produced between ground of said small-signal circuit and that of said power transistor;

• wherein
• said noise absorber ensures that said control signal produced by said small-signal circuit is transferred to said power transistor, without being affected by said noise voltage if produced;
• and
• said interface circuit further comprises a signal amplifier that converts the control signal outputted by said noise absorber, into signal level for turning on or off said power transistor.

A power converter comprising:

• a power transistor;
• a small-signal circuit for driving said power transistor;
• and
• an interface circuit for allowing the control signal to be transferred to said power transistor from said small-signal circuit;
• wherein,
• said interface circuit comprises a noise absorber that electrically absorbs noise voltage produced between ground of said small-signal circuit and that of said power transistor, by the stray inductance of said power transistor and a power module consisting of this power transistor;
• said noise absorber is operated as one of a constant voltage dead band generator that does not allow current to flow until a certain voltage is reached, and a constant current dead band generator that allows constant current to flow until a certain voltage is reached;
• and
• said noise absorber ensures that said control signal produced by said small-signal circuit is transferred to said power transistor, without being affected by said noise voltage if produced.

A power converter comprising:

• a power transistor;
• a small-signal circuit for driving said power transistor;
• and
• an interface circuit for allowing the control signal to be transferred to said power transistor from said small-signal circuit;
• wherein;
• said interface circuit comprises a noise absorber that electrically absorbs noise voltage produced between the ground of said small-signal circuit and that of said power transistor, by the stray inductance of said power transistor and a power module consisting of this power transistor;
• said noise absorber ensures that said control signal produced by said small-signal circuit is transferred to said power transistor, without being affected by said noise voltage if produced;
• said interface circuit further comprises a signal amplifier for converting the control signal outputted by said noise absorber, into the signal level for turning on or off said power transistor;
• and
• a difference between power voltage VDC of said interface circuit and logic voltage amplitude ΔVlogic of said signal amplifier (VDC−ΔVlogic) is set at a level higher than said noise voltage Vnoise.

A power converter comprising:

• a power transistor;
• a small-signal circuit for driving said power transistor;
• and
• an interface circuit for allowing the control signal to be transferred to said power transistor from said small-signal circuit;
• wherein;
• said interface circuit comprises a noise absorber that electrically absorbs noise voltage produced between the around of said small-signal circuit and that of said power transistor, by the stray inductance of said power transistor and a power module consisting of this power transistor;
• said noise absorber ensures that said control signal produced by said small-signal circuit is transferred to said power transistor, without being affected by said noise voltage if produced;
• a soft-switching gate-drive circuit for reducing the switching speed of said power transistor is arranged between said interface circuit and power transistor.

An electric vehicle comprising:

• a wheel drive motor;
• a power converter for converting d.c. power supplied from a d.c. power source into a.c. power, and for controlling the current supplied to said motor;
• wherein said power converter comprises:
• a power transistor;
• a motor small-signal circuit for driving said power transistor;
• and
• an interface circuit for transferring control signals from this motor small-signal circuit to said power transistor;
• wherein said interface circuit comprises a noise absorber that electrically absorbs the noise voltage produced between the ground of said small-signal circuit and that of said power transistor, by the stray inductance of said power transistor and a power module consisting of this power transistor;
• said electric vehicle further characterized in that said noise absorber ensures that said control signal produced by said small-signal circuit is transferred to said power transistor, without being affected by said noise voltage if produced.