Driving device for semiconductor switching element and control system for power converter

Patent metadata

Field	Value
Publication number	US-10081253-B2
Application number	US-201615012448-A
Country	US
Kind code	B2
Filing date	Feb 1, 2016
Priority date	Jan 30, 2015
Publication date	Sep 25, 2018
Grant date	Sep 25, 2018

Abstract

In a driving device for changing a semiconductor switching element, having an on-off control terminal, between an on state and an off state according to a power supply voltage input thereto, a constant-current driver generates a constant current based on the power supply voltage. The constant-current driver performs one of charging and discharging of the on-off control terminal of the semiconductor switching element based on the generated constant current so as to change the semiconductor switching element from one of the on state and off state to the other thereof. A rate varying unit adjusts, based on correlation information between the power supply voltage and the constant current, a value of the constant current so as to vary a rate of changing the semiconductor switching element from one of the on state and the off state to the other thereof.

First claim

What is claimed is:

1. A driving device for changing a semiconductor switching element, having an on-off control terminal, between an on state and an off state according to a power supply voltage input thereto, the driving device comprising:
a constant-current driver configured to generate a constant current based on the power supply voltage, and to perform at least one of charging and discharging of the on-off control terminal of the semiconductor switching element using the generated constant current so as to change the semiconductor switching element from one of the on state and off state to the other thereof; and
a rate varying unit to which the power supply voltage is input,
the rate varying unit including a storage that stores correlation information between the power supply voltage and the constant current, the rate varying unit being configured to adjust, based on the correlation information stored in the storage, a value of the constant current so as to vary a rate of changing the semiconductor switching element from one of the on state and the off state to the other thereof.

2. The driving device according to claim 1 , wherein the constant-current driver comprises at least one of:
a charging unit configured to generate, as the constant current, a first constant current based on the power supply voltage, and to charge the on-off control terminal of the semiconductor switching element based on the generated first constant current so as to change the semiconductor switching element from the off state to the on state; and
a discharging unit configured to generate, as the constant current, a second constant current based on the power supply voltage, and to discharge the on-off control terminal of the semiconductor switching element based on the generated second constant current so as to change the semiconductor switching element from the on state to the off state.

3. The driving device according to claim 2 , wherein the driving device comprises at least the charging unit.

4. The driving device according to claim 2 , wherein:
the driving device is connected to a power source for supplying the power supply voltage to the driving device;
the driving device comprises at least the charging unit; and
the charging unit comprises:
an adjustment resistor having opposing first and second ends, the first end being connected to the power source;
a constant-current source connected to the second end of the adjustment resistor and configured to generate an output current;
a charging resistor having opposing first and second ends, the first end being connected to the power source;
a charging switching element connected between the second end of the charging resistor and the on-off control terminal of the semiconductor switching element; and
a comparator driver connected to a connection point between the second end of the adjustment resistor and the constant-current source and connected to the second end of the charging resistor, the comparator driver being configured to:
compare a voltage at the connection point with a voltage at the second end of the charging resistor; and
drive the charging switching element according to a result of the comparison of the voltage at the connection point with the voltage at the second end of the charging resistor,

the correlation information represents a correlation between the constant current output from the constant-current source and the power supply voltage; and
the rate varying unit is configured to adjust, based on the correlation information and the power supply voltage, the value of the output current from the constant-current source, thus varying the value of the constant current.

5. The driving device according to claim 2 , wherein:
the driving device is connected to a power source for supplying the power supply voltage to the driving device;
the driving device comprises at least the charging unit; and
the charging unit comprises:
an adjustment resistor having opposing first and second ends and a variable resistance, the first end being connected to the power source;
a constant-current source connected to the second end of the adjustment resistor and configured to generate an output current;
a charging resistor having opposing first and second ends, the first end being connected to the power source;
a charging switching element connected between the second end of the charging resistor and the on-off control terminal of the semiconductor switching element; and
a comparator driver connected to a connection point between the second end of the adjustment resistor and the constant-current source and connected to the second end of the charging resistor, the comparator driver being configured to:
compare a voltage at the connection point with a voltage at the second end of the charging resistor; and
drive the charging switching element according to a result of the comparison of the voltage at the connection point with the voltage at the second end of the charging resistor,

the correlation information represents a correlation between the constant current output from the constant-current source and the resistance of the adjustment resistor, and
the rate varying unit is configured to adjust, based on the correlation information and the power supply voltage, a value of the resistance of the adjustment resistor, thus varying the value of the constant current.

6. The driving device according to claim 2 , wherein:
the driving device is connected to a power source for supplying the power supply voltage to the driving device;
the driving device comprises at least the charging unit; and
the charging unit comprises:
an adjustment resistor having opposing first and second ends, the first end being connected to the power source;
a constant-current source connected to the second end of the adjustment resistor and configured to output the constant current;
a charging resistor having opposing first and second ends and a variable resistance, the first end being connected to the power source;
a charging switching element connected between the second end of the charging resistor and the on-off control terminal of the semiconductor switching element; and
a comparator driver connected to a connection point between the second end of the adjustment resistor and the constant-current source and connected to the second end of the charging resistor, the comparator driver being configured to:
compare a voltage at the connection point with a voltage at the second end of the charging resistor; and
drive the charging switching element according to a result of the comparison of the voltage at the connection point with the voltage at the second end of the charging resistor;

the correlation information represents a correlation between the constant current output from the constant-current source and the resistance of the charging resistor, and
the rate varying unit is configured to adjust, based on the correlation information and the power supply voltage, a value of the resistance of the charging resistor, thus varying the value of the constant current.

7. The driving device according to claim 1 , further comprising
an isolated power supply system comprising:
a transformer including a primary coil and a secondary coil magnetically coupled to the primary coil and electrically isolated from the primary coil, the secondary coil being connected to the constant-current driver so that an output voltage across the secondary coil serves as the power supply voltage; and
an energization controller configured to control energization of the primary coil to adjust the output voltage across the secondary coil,

the constant-current driver being configured to measure the output voltage across the secondary voltage as the power supply

Assignees

• Denso Corp

Inventors

• Fukuta Junichi

Classifications

• H03K17/0412

  by measures taken in the control circuit · CPC title

• H03K17/168

  in composite switches · CPC title

• H02P21/22

  Current control, e.g. using a current control loop · CPC title

• H02P29/027

  the fault being an over-current · CPC title

• H03K17/162

  without feedback from the output circuit to the control circuit · CPC title