KR100296265B1 - Electronic control unit of over current protecting type for automobile - Google Patents

Abstract

PURPOSE: An electronic control unit(ECU) of an over current protecting type for an automobile is provided to prevent a damage of the ECU or an actuator due to the over current by sensing the over current caused to short circuit at a power system connected to the ECU and by cutting off the over current. CONSTITUTION: An electronic control unit(ECU)(100) comprises a microcomputer(110), a switching section(120) and an over current detecting portion(130). The microcomputer(110) outputs a switching control signal corresponding to an electronic signal converted at a first through a third sensor. The switching section(120) supply or cut off a power to an actuator(60) according to a switching control signal applied from the microcomputer(110). The over current detecting portion(130) senses an over current of the power applied to the actuator(60) according to a switching operation of the switching portion(120), and if the over current is detected, a switching off control signal is applied to the switching portion(120) in order to cut off the power applied to the actuator.

Description

Automotive overcurrent protection electronic control unit

The present invention relates to a vehicle, and more particularly, by detecting and blocking an overcurrent when an overcurrent occurs due to an accident such as a short circuit in a power supply system associated with an electronic control unit, to prevent damage to the electronic control unit and the actuator. An overcurrent protection electronic control unit.

In general, an automobile includes an engine for generating power, a power transmission device for driving the vehicle by converting the power generated from the engine into a rotational force of the wheel, a steering device configured to change a driving direction of the vehicle, and an impact received from a road surface. And a suspension device designed to attenuate to improve ride comfort and adjustment stability, and a braking device designed to stop the vehicle according to the driver's operation.

In the past automobiles, the components were operated only by mechanical mechanisms, but in modern automobiles, the components are operated by various electric and electronic devices in order to improve driving performance, safety / stability, ride comfort, and convenience. It controls the operation, and the electrical and electronic control mechanisms occupy a huge portion of the vehicle.

As shown in FIG. 1, a schematic control system for a vehicle as described above is illustrated in FIG. 1, and the first sensor 10 illustrated in the same drawing is a device that converts a driver's instruction operation into an electrical signal and is installed in an instrument panel. Various switches are included therein, and the second sensor 20 is a device that detects an operation or state of the mechanical devices constituting the vehicle and converts the same into an electrical signal.

In addition, the third sensor 30 detects a state of the surrounding environment of the vehicle and converts it into an electrical signal corresponding thereto.

The electrical signals converted by the first sensor 10, the second sensor 20, and the third sensor 30 are input to an electronic control unit (ECU) 40. In addition, the electronic control unit 40 detects the driver's instruction operation, the operating state of the mechanical devices, and the surrounding environment of the vehicle by the electric signal, and outputs an electric signal corresponding thereto.

Actuator (50) is an apparatus for converting the electrical signal applied from the electronic control unit 40 into a single force such as force, displacement or heat, a solenoid for converting the electrical signal into linear motion, various motors, This includes the relay drive circuit, the equalizer and the drive circuit of the display device.

In addition, the control mechanism mechanism 60 collectively refers to a mechanical mechanism whose operation is controlled by the force and displacement or heat, etc. converted by the actuator 50.

On the other hand, the electronic control unit 40 as described above is shown in Figure 2, the conventional electronic control unit 40 is a switching transistor 43 for supplying or cutting off the power supply to the actuator 60, the current A switching control signal corresponding to an electrical signal input from the limiting resistor 42, the first sensor 10, the second sensor 20, and the third sensor 30, respectively, is applied to the switching transistor 43. It consists of a microcomputer 41.

However, in the above-described configuration, when an over current flows due to a short circuit or a failure in the actuator 60, the switching transistor 43 or the actuator 60 of the electronic control unit 40 There was a problem of being damaged by the overcurrent.

Accordingly, the present invention has been made to solve the above problems, the present invention is to detect the overcurrent caused by an accident such as a short circuit in the power supply system associated with the electronic control unit, overcurrent protection of the vehicle that can block it The purpose is to provide a type electronic control unit.

The overcurrent protection type electronic control unit for a vehicle according to the present invention for achieving the above object is to supply or cut off power to an actuator that converts an electrical signal into a work such as force, displacement or heat according to a predetermined switching control signal. The switching unit and the microcomputer and the actuator which apply the switching control signal corresponding to the user's instruction operation detected by various sensors or the operation state of the main vehicle components or the data about the surrounding environment of the vehicle are applied to the switching unit. It is characterized by consisting of an overcurrent sensing unit for detecting an overcurrent generated in the power supply and applying a switching-off control signal to the switching unit to cut off the power applied to the actuator.

1 is a schematic block diagram of a control system of a typical vehicle.

2 is a schematic internal configuration diagram of a conventional electronic control unit.

3 is a schematic block diagram of an electronic control unit according to a preferred embodiment of the present invention.

FIG. 4 is a detailed block diagram of the overcurrent detector shown in FIG. 3 and a detailed circuit diagram of the switching unit.

FIG. 5 is a voltage or current waveform diagram showing an input / output relationship between internal components of the electronic control unit shown in FIG. 4; FIG.

6 is a circuit diagram illustrating another embodiment of the switching unit shown in FIG. 4.

* Explanation of symbols for main parts of the drawings

10 to 30: first to third sensors 40 and 100: electronic control unit

41, 110: microcomputers 42, 121, 144, 145: resistance

43, 122, 123, 141, 142, 143: Transistor 50: Control mechanism mechanism

60: actuator 120: switching unit

130: overcurrent detection unit 131: short pulse generating circuit

132: sample and hold circuit 133: comparison circuit

Hereinafter, preferred embodiments of an overcurrent protection electronic control unit for a vehicle according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 3 is a schematic block diagram of an electronic control unit according to a preferred embodiment of the present invention, wherein the electronic control unit 100 according to the present invention includes a first to third sensor (see 10 to 30 of FIG. 1). The microcomputer 110 outputs a switching control signal corresponding to the converted electrical signal, and the switching unit 120 supplies or cuts power to the actuator 60 according to the switching control signal applied from the microcomputer 110. And a switching 'off' control signal for detecting the presence of an overcurrent for the power supplied to the actuator 60 according to the switching operation of the switching unit 120, and for shutting off the power applied to the actuator when the overcurrent is detected. It consists of an overcurrent detection unit 130 to apply to the switching unit 120.

As shown in FIG. 4, the switching unit 120 supplies power to the actuator 60 according to a switching control signal applied by a predetermined level voltage drop from the microcomputer 110 by the resistor 121. The switching 'on' control signal of the switching control signal applied from the microcomputer 110 to the switching transistor 122 according to the switching transistor 122 to cut off and the switching 'off' control signal applied from the overcurrent sensing unit 130. It consists of a control transistor 123 which passes to the ground and blocks it.

In addition, the overcurrent detecting unit 130 receives a switching control signal output from the microcomputer 110 and generates a short pulse generation circuit 131 according to a signal period of the switching control signal. And a power signal applied to the actuator 60 and a pulse signal output from the short pulse generating circuit 131 according to the switching operation of the switching unit 120, and sampled the voltage component of the power supply according to the pulse signal. The sample-and-hold circuit 132 to be n-holded and output, and the hold voltage level held by the sample-and-hold circuit 132 are compared with a predetermined reference voltage level, and the switching is performed when the hold voltage is equal to or greater than the reference voltage level. And a comparison circuit 133 for outputting a switching 'off' control signal to the unit.

Hereinafter, an operation example of the present invention having the configuration as described above will be described in detail with reference to FIGS. 3 to 4.

First, when a switching 'on' control signal (a high level signal in ⓐ of FIG. 5) is output from the microcomputer 110, the signal is applied to the base end of the switching transistor 122 through the resistor 121. It is provided to the short pulse generating circuit 131.

Accordingly, the switching transistor 122 is biased and turned on, and power is applied to the actuator 60 through the turned-on switching transistor 122, thereby driving the actuator 60.

On the other hand, when the signal output from the microcomputer 110 outputs the switching 'on' control signal (a high level signal in Fig. 5A), the short pulse generating circuit 131 has a high level pulse signal of a predetermined width ( 5) is generated and applied to the sample and hold circuit 132.

At this time, the sample and hold circuit 132 samples the voltage level of the power applied to the actuator 60 (see ⓕ in FIG. 5) for one period of the high level pulse signal applied from the short pulse generating circuit 131. It is then held and applied to the comparison circuit 133.

Here, the voltage level of the power input to the sample and hold circuit 132 (see ⓕ in FIG. 5) is applied to the switching transistor 122 while the switching transistor 122 is turned on (in FIG. 5 in the low level signal. The voltage level drops as compared to while is turned off (signal of high level in ⓕ in Fig. 5).

However, when a fault such as a short circuit occurs in the actuator 60 or the power supply line and an overcurrent (see the current waveform of Ic in FIG. 5) flows, the voltage level of the power input to the sample and hold circuit 132 (FIG. 5 ⓕ) rises above the predetermined level.

Therefore, at this time, the voltage level held after sampling (see? Of FIG. 5) exceeds the reference voltage level.

When the hold voltage exceeding the reference voltage (see ⓒ in FIG. 5) is input to the comparison circuit 132, the comparison circuit 132 transmits a high level electric signal (see ⓓ in FIG. 5) of the control transistor 123. It is applied to the base end.

The control transistor 123 that receives the high level electric signal (see ⓓ in FIG. 5) from the comparison circuit 132 is turned on, and the switching 'on applied to the base end of the switching transistor 122 from the microcomputer 110. 'The control signal (high level signal in ⓐ of Figure 5) is passed to the ground to block.

Accordingly, the potential of the base end of the switching transistor 122 (see ⓐ in FIG. 5) falls to the low level, and the switching transistor 122 is turned off.

As the switching transistor 122 is turned off, power applied to the actuator 60 is cut off, and damage to the actuator 60 and the switching transistor 122 due to overcurrent is prevented.

On the other hand, when the switching 'off' control signal (low level signal in ⓐ of FIG. 5) is output from the microcomputer 110, the switching transistor 122 is turned off, and the power applied to the actuator 60 is cut off.

On the other hand, Figure 6 is a circuit diagram showing another embodiment of the switching unit shown in Figure 4, the switching unit according to another embodiment of the present invention, the presence or absence of the signal voltage applied to the base terminal through the resistor 145 According to the switching transistor 141 for supplying or cutting off power to the actuator according to the switching control signal applied from the microcomputer 110 through the resistor 144, the signal voltage applied to the base end of the switching transistor 141 When the switching 'off' control signal is applied from the first control transistor 142 and the overcurrent sensing unit 130 to control the switching operation of the switching transistor 141 by supplying or cutting off, it is output from the microcomputer 110. The second control transistor 143 is configured to pass and block a switching 'on' control signal among the switching control signals applied to the first control transistor 142 to ground.

Operation of the switching unit according to another embodiment of the present invention configured as described above is as follows.

First, when the switching 'on' control signal is output from the microcomputer 110 and applied to the base terminal of the first control transistor 142 through the resistor 144, the first control transistor 142 is turned on to supply power. A bias voltage applied to the base terminal of the switching transistor 141 through the resistor 145 is passed to ground to block.

Accordingly, the switching transistor 141 is turned on, and power is applied to the actuator 60 through the turned-on switching transistor 141.

At this time, when the switching 'off' control signal is applied to the base terminal of the second control transformer 143 by the overcurrent sensing unit 130, the second control transistor 143 is turned on, and the resistance ( The switching 'on' control signal applied to the base terminal of the first control transistor 142 is passed to the ground through the block 144.

Accordingly, the first control transistor 142 is turned off, so that a bias voltage is applied to the base terminal of the switching transistor 141 through the resistor 145 from the power supply.

As a result, the switching transistor 141 is turned off, and the power applied to the actuator 60 is cut off.

On the other hand, when the switching 'off' control signal is output from the microcomputer 110 and applied to the base terminal of the first control transistor 142 through the resistor 144, the first control transistor 142 is turned off, As a result, a bias voltage is applied to the base terminal of the switching transistor 141 from the power supply through the resistor 145.

As a result, the switching transistor 141 is turned off, and the power applied to the actuator 60 is cut off.

As described above, according to the overcurrent protection type electronic control unit of a vehicle according to the present invention, since the overcurrent generated by an accident such as a short circuit is detected in the power supply system associated with the electronic control unit and cuts it off, it is linked with the electronic control unit. There is an effect that can prevent the electronic control unit and the actuator from being damaged by the overcurrent flowing in the power supply system.

Claims (3)

A switching unit for supplying or cutting off power to an actuator for converting an electrical signal into a quantity such as force, displacement, or heat according to a predetermined switching control signal; A microcomputer for applying a switching control signal corresponding to a user's instruction operation detected by various sensors, an operation state of an automobile main component, or data on an environment of an automobile; A short pulse generating circuit for receiving a switching control signal output from the microcomputer and generating a pulse signal having a predetermined width according to a signal period of the switching control signal, a power applied to the actuator, and an output from the short pulse generating circuit; A sample-and-hold circuit that receives a pulse signal and samples and holds the voltage component of the power supply according to the period of the pulse signal, and compares the hold voltage level held by the sample-and-hold circuit with a predetermined reference voltage level. An overcurrent detecting unit comprising a comparing circuit for outputting a switching-off control signal to the switching unit when the hold voltage level is equal to or higher than the reference voltage level; Overcurrent protection electronic control unit of a vehicle, characterized in that consisting of. The method of claim 1, The switching unit, a switching transistor for supplying or blocking power to the actuator in accordance with a switching control signal applied from the microcomputer, When the switching off control signal is applied from the overcurrent sensing unit, the control transistor for outputting the switching control signal to the ground of the switching control signal output from the microcomputer applied to the transistor to block the vehicle. Electronic control unit with overcurrent protection. The method of claim 1, The switching unit, a switching transistor for supplying or cutting off the power to the load in accordance with the presence or absence of a signal voltage applied to the base end; A first control transistor for controlling a switching operation of the switching transistor by supplying or cutting off a signal voltage to a base end of the switching transistor according to a switching control signal applied from the microcomputer; When a switching off control signal is applied from the overcurrent sensing unit, the switching control signal is output from the microcomputer and is configured as a second control transistor which passes a switching-on control signal to ground and blocks the switching control signal applied to the first control transistor. An overcurrent protection electronic control unit for a vehicle.