STARTER DRIVING SEMICONDUCTOR SWITCH APPARATUS

• US 20110298276A1
• Filed: 12/07/2010
• Published: 12/08/2011
• Est. Priority Date: 06/07/2010
• Status: Active Grant

• Current Assignee: Mitsubishi Electric Corporation
• Original Assignee: Mitsubishi Electric Corporation
• Inventors: TAKAHASHI, Yasuhiro, TANAKA, Takaaki, KUBO, Toru, UMEMOTO, Hideki, HATA, Toshiaki
• Granted Patent: US 8,829,710 B2
• Time in Patent Office: Days
• US Class Current: 307/10.6
• CPC Class Codes: F02N 11/0818 Conditions for starting or stopping the engine or for deactivating the idle-start-stop mode
• CPC Class Codes: F02N 11/0825 related to prevention of engine restart failure, e.g. disabling automatic stop at low battery state
• CPC Class Codes: F02N 11/087 Details of the switching means in starting circuits, e.g. relays or electronic switches
• CPC Class Codes: F02N 11/10 Safety devices F02N11/08 takes precedence
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A starter driving semiconductor switch apparatus energizes and de-energizes a starter according to a command from an outside. A series circuit to which semiconductor switches are connected in series is provided between a battery serving as a power supply and the starter. The starter is energized by bringing all the semiconductor switches into conduction. A voltage or a current at a predetermined point in the series circuit is monitored to make a self-diagnosis on whether the starter is allowed to start and whether there is a failure in the semiconductor switches according to a monitor output. The starter driving semiconductor switch apparatus is thus expected to have a longer useful life by energizing the starter not by using mechanical contacts but by using semiconductor switches.

Claims

1. A starter driving semiconductor switch apparatus that energizes and de-energizes a starter according to commands from an outside, comprising:

a series circuit provided between a battery serving as a power supply and the starter, to which a plurality of semiconductor switches are connected in series,

wherein;

the starter is energized by bringing all the semiconductor switches into conduction; and

one of a voltage and a current at a predetermined point in the series circuit is monitored to make a self-diagnosis on whether the starter is allowed to start and whether there is a failure in the semiconductor switches according to a monitor output.

2. The starter driving semiconductor switch apparatus according to claim 1, wherein:

a battery-side voltage of a semiconductor switch closest to the battery in the plurality of semiconductor switches is monitored and in a case where the voltage being monitored is below a predetermined voltage, a diagnosis result indicating that the starter is not allowed to restart is outputted to the outside.

3. The starter driving semiconductor switch apparatus according to claim 1, wherein:

a starter-side voltage of a semiconductor switch closest to the starter in the plurality of semiconductor switches is monitored and in a case where the voltage being monitored is equal to or higher than a predetermined voltage in a period during which the starter is not energized, a diagnosis result indicating a semiconductor switch failure is outputted to the outside.

4. The starter driving semiconductor switch apparatus according to claim 1, wherein:

a voltage between the plurality of semiconductor switches is monitored and in a case where a semiconductor switch closer to the battery than a monitoring point is in a conducting state but the voltage being monitored is below a predetermined voltage, a diagnosis result indicating that the starter is not allowed to restart is outputted to the outside.

5. The starter driving semiconductor switch apparatus according to claim 1, wherein:

a voltage between the plurality of semiconductor switches is monitored and in a case where a semiconductor switch closer to the battery than a monitoring point is in a non-conducting state but the voltage being monitored is equal to or higher than a predetermined voltage, a diagnosis result indicating a semiconductor switch apparatus failure is outputted to the outside.

6. The starter driving semiconductor switch apparatus according to claim 1, wherein:

all of the plurality of semiconductor switches are brought into conduction for a short time to monitor a current flowing into the semiconductor switches, and in one of a case where a current equal to or higher than a first predetermined current value is detected and a case where a current below a second predetermined current value is detected, a diagnosis result indicating that the starter is not allowed to restart is outputted to the outside.

7. The starter driving semiconductor switch apparatus according to claim 1, further comprising:

a diagnosis semiconductor switch that brings a path between a battery side of a semiconductor switch closest to the battery in the plurality of semiconductor switches and a battery side of a semiconductor switch closest to the starter into and out of conduction,

wherein the diagnosis semiconductor switch and the semiconductor switch closest to the starter are brought into conduction for a short time to monitor a starter-side voltage of the semiconductor switch closest to the starter, and in one of a case where a voltage equal to or higher than a first predetermined voltage value is detected and a case where a voltage below a second predetermined voltage value is detected, a diagnosis result indicating that the starter is not allowed to restart is outputted to the outside.

8. The starter driving semiconductor switch apparatus according to claim 6, wherein:

the self-diagnosis is made using a diagnosis request signal received from a device that determines an execution of an idle stop as a trigger, and a diagnosis result indicating one of a state where the starter is not allowed to restart and a normal state is outputted to the device that determines an execution of an idle stop.

9. The starter driving semiconductor switch apparatus according to claim 1, wherein:

start command signals are received from the outside and whether the starter is energized or de-energized is controlled depending whether both a result of recognizing a start command signal by a first energization determination portion and a result of recognizing the start command signal by a second energization determination portion indicate that energization is enabled.

10. The starter driving semiconductor switch apparatus according to claim 9, wherein:

the first energization determination portion performs processing in software by a micro processor and the second energization determination portion performs processing by an electric circuit.

11. The starter driving semiconductor switch apparatus according to claim 10, wherein:

the second energization determination portion forcedly enables energization only for a predetermined short period according to a command from the micro processor and brings the plurality of semiconductor switches into conduction during the short period for the self-diagnosis to be made.

12. A starter driving semiconductor switch apparatus that energizes and de-energizes a starter according to commands from an outside, comprising:

a plurality of semiconductor switches that are connected in series between a battery serving as a power supply and the starter;

driving circuits that are provided to the semiconductor switches in a one-to-one correspondence to drive the respective corresponding semiconductor switches;

a voltage monitor that monitors at least a starter-side voltage of a semiconductor switch closest to the starter in the plurality of semiconductor switches and a voltage between the plurality of semiconductor switches;

a current monitor that monitors a current flowing into the plurality of semiconductor switches;

a micro processor that makes a diagnosis on whether the starter is allowed to start and whether there is a failure in the semiconductor switches according to the commands, an output from the voltage monitor, and an output from the current monitor and outputs a diagnosis result to an ECU (Engine Control Unit);

an energization enable and disable determination circuit that outputs an energization enable and disable signal to the starter depending on whether a predetermined condition is satisfied according to the commands, an output to the micro processor, and an output from the current monitor; and

drive circuits that are provided to the plurality of semiconductor switches in a one-to-one correspondence to drive the respective corresponding semiconductor switches according to an output signal of the micro processor and the energization enable and disable signal.

13. A starter driving semiconductor switch apparatus that energizes and de-energizes a starter according to commands from an outside, comprising:

a plurality of semiconductor switches that are connected in series between a battery serving as a power supply and the starter;

driving circuits that are provided to the semiconductor switches in a one-to-one correspondence to drive the respective corresponding semiconductor switches;

a voltage monitor that monitors a battery-side voltage of a semiconductor switch closet to the battery in the plurality of semiconductor switches, a starter-side voltage of a semiconductor switch closest to the starter, and a voltage between the plurality of semiconductor switches;

a micro processor that makes a diagnosis on whether the starter is allowed to start and whether there is a failure in the semiconductor switches according to the commands and an output of the voltage monitor and outputs a diagnosis result to an ECU (Engine Control Unit);

an energization enable and disable determination circuit that outputs an energization enable and disable signal to the starter according to the commands and an output of the micro processor;

drive circuits that are provided to the plurality of semiconductor switches in a one-to-one correspondence to drive the respective corresponding semiconductor switches according to an output of the micro processor and the energization enable and disable signal;

a diagnosis semiconductor switch that is connected between a battery side of the semiconductor switch closest to the battery in the plurality of semiconductor switches and a battery side of the semiconductor switch closest to the starter; and

a drive circuit that brings the diagnosis semiconductor switch together with the semiconductor switch closest to the starter into conduction for a short time by an output of the micro processor when a failure diagnosis is made.

14. A starter driving semiconductor switch apparatus that energizes and de-energizes a starter according to commands from an outside, comprising:

a plurality of semiconductor switches that are connected in series between a battery serving as a power supply and the starter;

a plurality of voltage monitors that respectively monitor a battery-side voltage of a semiconductor switch closest to the battery in the plurality of semiconductor switches, a starter-side voltage of a semiconductor switch closest to the starter, and a voltage between the plurality of semiconductor switches;

an output circuit that outputs a result of comparison between outputs of the plurality of voltage monitors and a predetermined determination voltage to an ECU (Engine Control Unit) as a failure diagnosis output;

drive circuits that are provided to the plurality of semiconductor switches in a one-to-one correspondence to drive the respective corresponding semiconductor switches according to the commands;

a diagnosis semiconductor switch that is connected between a battery side of the semiconductor switch closest to the battery in the plurality of semiconductor switches and a battery side of the semiconductor switch closest to the starter; and

a drive circuit that brings the diagnosis semiconductor switch together with the semiconductor switch closest to the starter into conduction for a short time according to one command from the outside and a diagnosis request signal from the ECU (Engine Control Unit) when a failure is diagnosed.