KR101673345B1 - Method and device for measuring insulation resistance of fuel cell electric vehicle - Google Patents

Abstract

A method of measuring an insulation resistance of a fuel cell vehicle, comprising the steps of: determining whether a DC link voltage supplied to an inverter for driving a motor of a fuel cell vehicle is equal to or greater than a threshold voltage; The control unit includes a step of transmitting an insulation resistance measurement command for instructing a stack voltage monitoring unit for monitoring the voltage of the fuel cell included in the fuel cell vehicle to measure the insulation resistance of the fuel cell vehicle.

Description

TECHNICAL FIELD The present invention relates to a method of measuring insulation resistance of a fuel cell vehicle,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel cell vehicle related technology, and more particularly, to a method of measuring insulation resistance of a fuel cell vehicle and an insulation resistance measuring device.

A fuel cell is a kind of power generation device that converts chemical energy generated by oxidation of fuel directly into electric energy. Unlike a chemical cell, which basically uses oxidation and reduction reactions, unlike a chemical cell that performs a cell reaction inside a closed system, the difference is that the reactants are continuously supplied from the outside and the reaction products are continuously removed from the system have. In recent years, fuel cells have been put to practical use, and since reaction products of fuel cells are pure water, studies for use as energy sources for environmentally friendly vehicles have been actively conducted.

In order to use energy efficiently, the fuel cell vehicle is composed of a hybrid system using a secondary energy storage device such as a battery or a supercapacitor in addition to a fuel cell as a primary energy source. Here, bi-directional converters charge and discharge appropriate energy through energy storage devices such as batteries to maintain a constant fuel utilization rate and to balance the power between the fuel cell and the load.

In other words, a fuel cell hybrid vehicle, which is one of environmentally friendly future vehicles, continuously outputs a constant electric power from the fuel cell, and when the electric power is insufficient, the electric power from the electric vehicle battery (EV battery) An auxiliary output mode is applied. A bidirectional DC / DC converter (BHDC) is required for charging and discharging control of the EV battery because the voltage range of the fuel cell, which is the main power source, and the EV battery, the auxiliary power source, differ greatly.

The eco-friendly automobile refers to a vehicle system in which a high voltage battery is mounted and an electric motor is stored in a battery. A fuel cell vehicle, which is an environmentally friendly automobile, refers to a vehicle system in which a fuel cell using a chemical reaction between hydrogen and oxygen is used as an electricity source and an electric motor generated by a fuel cell is driven.

In the case of a vehicle system using such a high voltage battery or a fuel cell, since the breakdown of the insulation resistance is dangerous to the occupant, it is necessary to measure the insulation resistance and remove the risk in advance or warn the occupant.

The matters described in the background section are intended to enhance the understanding of the background of the invention and may include matters not previously known to those skilled in the art.

A technical object of the present invention is to provide a stack voltage monitor unit (SVM) which can monitor a voltage of a fuel cell when a DC link voltage is equal to or more than a threshold voltage for measuring insulation resistance when a fuel cell voltage disappears, (BMS) can measure the insulation resistance when the DC link voltage is less than the threshold voltage by measuring the insulation resistance of the fuel cell.

In order to solve the above problems, a method of measuring insulation resistance of a fuel cell vehicle according to an embodiment of the present invention is characterized in that the control unit controls the DC link voltage supplied to the inverter for driving the motor of the fuel cell vehicle, Judging whether or not it is possible; And when the DC link voltage is equal to or higher than the threshold voltage according to the determination result, the control unit controls the stack voltage monitor unit monitoring the voltage of the fuel cell included in the fuel cell vehicle, And transmitting an insulation resistance measurement command to command the measurement.

Wherein the control unit includes a battery management system (BMS) for monitoring a voltage of a battery included in the fuel cell vehicle when the DC link voltage is less than the threshold voltage according to the determination result, And transmitting an insulation resistance measurement command for commanding an insulation resistance measurement of the fuel cell vehicle.

The threshold voltage may be an operating voltage of the battery.

The mode of the fuel cell vehicle when the DC link voltage is less than the threshold voltage may include an idle stop mode, an electric vehicle (EV) mode, or a downhill running mode.

Wherein the insulation resistance is a resistance between a plus (+) high voltage terminal of the fuel cell connected to the inverter and a chassis ground included in the fuel cell vehicle or between a minus (-) high voltage terminal of the fuel cell connected to the inverter and the chassis ground Resistors.

In order to solve the above problems, an apparatus for measuring insulation resistance of a fuel cell vehicle according to an embodiment of the present invention includes a controller for determining whether a DC link voltage supplied to an inverter for driving a motor of the fuel cell vehicle is equal to or greater than a threshold voltage ; And monitoring the voltage of the fuel cell included in the fuel cell vehicle and instructing the control unit to measure the insulation resistance of the fuel cell vehicle when the DC link voltage is equal to or higher than the threshold voltage in accordance with the determination result And a stack voltage monitor for receiving the insulation resistance measurement command.

The apparatus for measuring insulation resistance of a fuel cell vehicle according to claim 1, further comprising: a voltage monitoring unit for monitoring a voltage of a battery included in the fuel cell vehicle and for outputting, when the DC link voltage is lower than the threshold voltage, And a battery management system (BMS) that receives an insulation resistance measurement command that commands an insulation resistance measurement.

The threshold voltage may be an operating voltage of the battery.

The mode of the fuel cell vehicle when the DC link voltage is less than the threshold voltage may include an idle stop mode, an electric vehicle (EV) mode, or a downhill running mode.

Wherein the insulation resistance is a resistance between a plus (+) high voltage terminal of the fuel cell connected to the inverter and a chassis ground included in the fuel cell vehicle or between a minus (-) high voltage terminal of the fuel cell connected to the inverter and the chassis ground Resistors.

The method and apparatus for measuring insulation resistance of a fuel cell vehicle according to an embodiment of the present invention can measure insulation resistance even in an idle stop or an electric vehicle mode during driving of a fuel cell vehicle.

The method and apparatus for measuring insulation resistance of a fuel cell vehicle according to the present invention can reduce the measurement delay time of insulation resistance from 9 minutes to 1 minute at maximum.

Further, the present invention can meet the measurement range of insulation resistance by changing software (logic) logic without additional development cost. That is, the present invention can satisfy the insulation resistance law of the fuel cell vehicle.

BRIEF DESCRIPTION OF THE DRAWINGS For a more complete understanding of the drawings used in the detailed description of the present invention, a brief description of each drawing is provided.
1 is a view for explaining an example of a method of measuring insulation resistance of a fuel cell vehicle.
2 is a view illustrating an apparatus for measuring insulation resistance of a fuel cell vehicle according to an embodiment of the present invention.
3 is a graph illustrating a method of measuring insulation resistance of a fuel cell vehicle according to an embodiment of the present invention.
4 is a flow chart illustrating a method of measuring an insulation resistance of a fuel cell vehicle according to an embodiment of the present invention.
5 is a view for explaining a method of measuring an internal insulation resistance of a controller applicable to the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS For a better understanding of the present invention, and the objects attained by the practice of the invention, reference should be made to the accompanying drawings, which illustrate embodiments of the invention, and to the description in the accompanying drawings.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with reference to embodiments of the present invention with reference to the accompanying drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear. Like reference numerals in the drawings denote like elements.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, the terms "comprises" or "having", etc., are used to specify that a feature, a number, a step, an operation, an element, a component, or a combination thereof, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

Throughout the specification, when a part is referred to as being "connected" to another part, it is not necessarily the case that it is "directly connected", but also "electrically or mechanically connected" .

Unless defined otherwise, terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and, unless expressly defined herein, are to be construed as either ideal or overly formal Do not.

BACKGROUND OF THE INVENTION Vehicles having a high voltage power source (such as a fuel cell or a battery) (e.g., a hybrid electric vehicle (HEV), an electric vehicle (EV), or a fuel cell electric vehicle (FCEV)) have low insulation resistance And then notify the driver.

In the method of measuring the insulation resistance only on the fuel cell system side compared with the present invention, the method of measuring the insulation resistance of the fuel cell system according to the present invention is characterized in that the fuel cell voltage (for example, There is a problem that the insulation resistance can not be measured for a maximum of 9 minutes.

1 is a view for explaining an example of a method of measuring insulation resistance of a fuel cell vehicle.

A method of measuring insulation resistance on the side (side) of a fuel cell (FUELCELL) will be described with reference to FIG.

The SVM (Stack Voltage Monitor) internal circuit measures the insulation resistance (Ri1, Ri2) based on the fuel cell voltage at the fuel cell side using the resistance partial pressure measurement method.

However, when the fuel cell (FUELCELL) voltage shown in Fig. 1 disappears (e.g., emergency EV mode, steel sheet, idle stop during running), the insulation resistance can not be measured. For example, if idle stop is entered during driving, it is impossible to measure the insulation resistance for a maximum of 9 minutes, and measurement delay occurs.

Next, referring to FIG. 1, a method of measuring the insulation resistance on the side (battery) side will be described.

The BMS internal circuit measures the insulation resistance (Ri1, Ri2) based on the battery voltage at the high-voltage battery side using a resistive divider. The insulation resistance measurement method using the resistance partial pressure measurement method in the BMS internal circuit is similar to the insulation resistance measurement method using the resistance partial pressure measurement method in the SVM internal circuit and the internal resistance value is measured by the resistance partial pressure measurement method Which is different from the case of the insulation resistance measuring method using

However, if the BHDC (bidirectional high voltage DCDC converter) shown in FIG. 1 outputs a voltage higher than the battery voltage, it can not detect insulation breakdown. More specifically, the BMS is designed to match the battery voltage, so insulation measurements (measurement of insulation resistance) may not be possible if the BHDC output voltage is higher than the battery voltage.

Next, a method of measuring the insulation resistance in the BHDC or the inverter will be described with reference to FIG.

It may be necessary to develop a novel circuit to measure the insulation resistance. Since the fuel cell voltage and the high voltage during regenerative braking are applied to the BHDC or INVERTER during operation, the insulation resistances Ri1 and Ri2 can be measured using the DC link voltage measured at the output terminal of the BHDC or the input terminal of the INVERTER. However, switching of the power devices (IGBTs) included in the BHDC or INVERTER may have the disadvantage of interfering with the insulation measurement. Insulation resistance measurements may not be possible when the BHDC is off (no starting keyon and no starting).

Next, a method of measuring the insulation resistance using the independent insulation measurement device will be described.

The insulation resistance measuring method may be a method of measuring the insulation resistance by applying a frequency power to the high voltage terminals (HV +, HV-) of the insulation measuring apparatus. However, in the case of this insulation resistance measuring method, the accuracy is lowered due to the stray capacitance (due to stray capacitance), and optimization may be required for measuring the insulation resistance of the fuel cell electric vehicle (FCEV) according to the present invention.

2 is a view illustrating an apparatus for measuring insulation resistance of a fuel cell vehicle according to an embodiment of the present invention.

Referring to FIG. 2, the fuel cell vehicle 100 includes a control unit (FUELCELL CONTROL UNIT, FCU) 105, a fuel cell FUELCELL used as a main power source of the vehicle, a stack voltage monitor (SVM) 120, an inverter 125, a traction motor 130, a DC / DC converter 135, a battery management system (BMS) 140, and an auxiliary power source And a battery BATTERY.

The fuel cell vehicle 100 uses a fuel cell that generates electricity by itself in combination with hydrogen and oxygen in air instead of a gasoline internal combustion engine as a power source, operates the electric motor 130 with electric energy generated through the fuel cell system, So that the vehicle can be driven. The fuel cell vehicle 100 may be configured as a hybrid system using a secondary energy storage device such as a fuel cell (FUELCELL) and a battery (BATTERY), which are primary energy sources, in order to utilize energy efficiently.

The fuel cell FUELCELL is supplied with hydrogen from a hydrogen tank (not shown) and supplied with air from an air blower (not shown) to generate electricity by electrochemical reaction between hydrogen and oxygen in the air. The fuel cell may be a unit cell or a fuel cell stack in which a plurality of unit cells are connected in series.

The battery (BATTERY) charges the electricity generated by the fuel cell (FUELCELL) and includes various fuel cell types (BOP: Balance of Plant) (air blower, hydrogen recirculation blower, And the like.

A battery management system (BMS) (or a battery management system unit) 140 controls a charging or discharging process of a battery BATTERY including unit cells 145 that can be connected in series with each other .

The battery management system (BMS) 140 monitors (measures or senses) various states of the unit cells 145 to measure the temperature of the unit cells, the ambient temperature of the unit cells, the voltages of the unit cells, (Or charging) current, etc., and can inform the operator of the apparatus of the battery status and manage the unit cell 145 in an appropriate state.

The DC / DC converter 135 is a bidirectional high voltage DC / DC converter (BHDC), and includes a high voltage battery BATTERY and a fuel cell FUELCELL including unit cells 115 that can be connected in series with each other. And may be a bidirectional converter that matches the balance of the other output voltages. That is, it boosts the voltage from the high voltage battery and outputs it to the high voltage bus terminals HV (+) and HV (-) to start the fuel cell FUELCELL, And a function of charging the high-voltage battery (BATTERY) by lowering the high voltage to a predetermined voltage during braking. The DC / DC converter 135 may perform a function of discharging a current when the motor 130 is driven.

The inverter 125 switches the voltage input from the high voltage bus end to convert it into a three-phase alternating current power and supply it to the driving power source of the motor 130.

The control unit 105 can control the operation of the SVM 120, the inverter 125, the DC / DC converter 135, and the BMS 140 via a command line.

The Isolation Resistor 1 155 shown in FIG. 2 can indicate an insulation resistance between a minus high voltage terminal HV and a chassis ground and the Isolation Resistor 2 110, (+) High-voltage terminal HV (+) and the chassis ground due to the insulation resistance at the fuel cell FUELCELL side, and the Isolation Resistor 3 150 can exhibit insulation resistance at the side of the battery BATTERY The insulation resistance can indicate the insulation resistance between the positive (+) high voltage terminal (HV (+)) and the chassis ground. The chassis represents the chassis of the vehicle excluding the vehicle body. The chassis may include, for example, a power transmission device, a suspension device, a brake device, or a steering device.

Referring to FIG. 2, an apparatus for measuring insulation resistance of a fuel cell vehicle according to an embodiment of the present invention will now be described.

The insulation resistance measuring apparatus of the fuel cell vehicle may include a control unit 105 and a stack voltage monitor unit (SVM) 120.

The control unit 105 can determine whether the DC link voltage supplied to the inverter 125 driving the motor 130 of the fuel cell vehicle 100 is equal to or higher than the threshold voltage.

The stack voltage monitor unit (SVM) 120 monitors the voltage of the fuel cell FUELCELL included in the fuel cell vehicle 100 and outputs the DC link voltage from the control unit 105 And may receive an insulation resistance measurement command that commands (instructs) insulation resistance measurement of the fuel cell vehicle 100 when the threshold voltage is equal to or higher than the threshold voltage.

The insulation resistance measuring apparatus of the fuel cell vehicle may further include a battery management system (BMS) 140. The battery management system (BMS) 140 monitors the voltage of the battery BATTERY included in the fuel cell vehicle 100, and when the DC link voltage is less than the threshold voltage , And an insulation resistance measuring command to command the insulation resistance measurement of the fuel cell vehicle 100. [

The threshold voltage may be an operation voltage (storage voltage) of the battery BATTERY.

1) between the positive (+) high voltage terminal HV (+) of the fuel cell FUELCELL connected to the inverter 125 and the chassis ground included in the fuel cell vehicle 100, (Ri2 shown in FIG. 1) between the negative (-) high voltage terminal HV (-) of the fuel cell (FUELCELL) connected to the inverter 125 and the chassis ground .

The mode of the fuel cell vehicle 100 when the DC link voltage is less than the threshold voltage may be an idle stop mode (or an idle stop mode of the fuel cell during running), an electric vehicle mode Emergency EV mode), or a downhill running mode (or a long downhill running mode).

The idle stop mode may indicate a mode in which the vehicle is stopped and the voltage of the fuel cell disappears. The idle stop mode may mean a power generation stop operation mode of the fuel cell. The EV mode may mean a mode in which the vehicle travels while receiving a high voltage battery (BATTERY) rotor power. In the idle stop mode, EV mode, and downhill running mode, the vehicle load can be powered only by a high voltage battery (BATTERY).

A method of measuring insulation resistance of a fuel cell vehicle according to an embodiment of the present invention will be described with reference to FIGS. 2 and 4. FIG. 4 is a flow chart illustrating a method of measuring an insulation resistance of a fuel cell vehicle according to an embodiment of the present invention.

According to the measurement step 205, the voltage of the fuel cell (FUELCELL) including a plurality of fuel cell unit cells (115) is measured. The voltage of the battery BATTERY including the plurality of unit cells 145 is measured. The DC link voltage at the output terminal of the fuel cell FUELCELL and at the output terminal of the DC / DC converter 135 connected to the battery BATTERY can be measured. The threshold voltage can be determined (or determined). The threshold voltage may be the operating voltage of the battery BATTERY at present. The threshold voltage may be 180 (V) or higher and 270 (V) or lower, for example, a voltage proportional to the number of cells of the battery.

The measurement of the fuel cell voltage, the measurement of the battery voltage, the measurement of the DC link voltage, and the determination of the threshold voltage may be performed by the control unit (FCU) 105.

According to decision step 210, the controller (FCU) 105 may determine whether the DC link voltage is above a threshold voltage.

If the DC link voltage is equal to or higher than the threshold voltage, the process of the insulation resistance measuring method 200 of the fuel cell vehicle 100 proceeds to the first measurement command step 215. If the DC link voltage is below the threshold voltage, The discharge voltage control step 225 may be performed.

According to the first measurement command step 215, the control unit (FCU) 105 can instruct the stack voltage monitor unit (SVM) 120 to measure the insulation resistance.

According to the insulation resistance measuring step 220, the stack voltage monitor unit (SVM) 120 can measure the insulation resistance of the fuel cell vehicle 100 above the threshold voltage.

The stack voltage monitor unit (SVM) 120 measures the resistance value of the fuel (e.g., fuel) by a method similar to the method of measuring the insulation resistance Ri1 and Ri2 using the resistance partial pressure measurement method using the SVM (Stack Voltage Monitor) internal circuit described with reference to FIG. The insulation resistance of the battery cell 100 can be measured. In this measurement method, the insulation resistance value can be obtained using the resistors R1 and R2, the switches SW1 and SW2, and the voltage sensor included in the SVM internal circuit shown in FIG.

According to the discharge voltage control step 225, the DC / DC discharge voltage can be controlled by the BMS 140. The discharge voltage may be equal to the battery voltage.

According to the second measurement command step 230, the controller (FCU) 105 may instruct the battery management system (BMS) 140 to measure the insulation resistance.

According to the insulation resistance measuring step 235, the battery management system (BMS) 140 can measure the insulation resistance of the fuel cell vehicle 100 below the threshold voltage.

The battery management system (BMS) 140 measures the resistance value of the fuel cell vehicle 100 in a similar manner to the method of measuring the insulation resistance Ri1 and Ri2 using the resistance partial pressure measurement method by the above-described stack voltage monitor unit (SVM) The insulation resistance can be measured.

During normal operation, the output voltage (inverter side voltage) of DC / DC converter 135 may be higher than the battery lower limit voltage and lower than the fuel cell maximum voltage.

When the voltage of the fuel cell falls below the threshold voltage, the DC / DC converter 135 can control the discharge voltage between the battery's minimum voltage and the battery's maximum voltage.

A method of measuring the insulation resistance of the fuel cell vehicle will now be described with reference to FIGS. 2 and 4. FIG.

The control unit 105 can determine whether the DC link voltage supplied to the inverter 130 driving the motor 130 of the fuel cell vehicle 100 is equal to or higher than the threshold voltage. The control unit 105 controls the stack voltage monitor unit 120 to monitor the voltage of the fuel cell FUELCELL included in the fuel cell vehicle 100 when the DC link voltage is equal to or greater than the threshold voltage (Or transmit) an insulation resistance measurement command to command an insulation resistance measurement of the fuel cell vehicle 100. [

The control unit 105 controls the battery management system 100 to monitor the voltage of the battery BATTERY included in the fuel cell vehicle 100 when the DC link voltage is lower than the threshold voltage according to the determination result, (BMS) 140 to an insulation resistance measurement command to command the insulation resistance measurement of the fuel cell vehicle 100.

The threshold voltage may be an operating voltage of the battery.

The insulation resistance is a resistance between the positive (+) high voltage terminal HV (+) of the fuel cell FUELCELL connected to the inverter 125 and the chassis ground included in the fuel cell vehicle 100, (-) high voltage terminal HV (-) of the fuel cell FUELCELL connected to the high voltage terminal 125 and the chassis ground.

The mode of the fuel cell vehicle 100 when the DC link voltage is less than the threshold voltage includes an idle stop mode (or an idle stop mode of the fuel cell), an electric vehicle mode (or an emergency EV Mode), or a downhill running mode (or a long downhill running mode).

As described above, according to the present invention, the operating conditions are set and the insulation resistance is measured according to the conditions by a fuel cell insulation resistance measuring device (stack voltage monitoring part (SVM) 120) and a battery insulation resistance measuring device ) ≪ / RTI > 140) may be provided. The present invention can shorten the insulation resistance measurement delay time from 9 minutes to 1 minute.

3, when the DC link voltage is equal to or greater than a threshold value (threshold voltage) for measuring the insulation resistance when the fuel cell voltage disappears, the stack voltage monitor unit (SVM) 120 The insulation resistance of the fuel cell vehicle 100 is measured The battery management system (BMS) 140 measures the insulation resistance when the DC link voltage is less than the threshold (threshold voltage).

That is, according to the present invention, the measurement device is distinguished according to the voltage range of the DC link, the BMS measures the insulation resistance at a voltage lower than the threshold voltage, and the SVM (Stack Voltage Monitor) measures the insulation resistance at a voltage higher than the threshold voltage.

5 is a view for explaining a method of measuring an internal insulation resistance of a controller applicable to the present invention. Fig. 5 shows the ECE R100 of an electric vehicle.

The controller may correspond to a controller (FCU) 105, a stack voltage monitor (SVM) 120, and a battery management system (BMS) 140 shown in FIG. 2, The traction system may correspond to the fuel cell FUELCELL of FIG. 2, the traction system may correspond to the traction motor 130 of FIG. 2, and the rechargeable energy storage systems RESS may correspond to the battery BATTERY of FIG.

Fig. 5A shows the measurement of Vb, V1 and V2.

In FIG. 5A, Vb indicates a voltage between high voltages (+) and (-) corresponding to HV (+) and HV (-) in FIG. 2, V1 indicates a high voltage V2 is the voltage between the high voltage (+) and the electrical chassis (or electrical chassis ground), and V2 is the voltage between the high voltage (+) and the electrical chassis (or electrical chassis ground).

5 (b), when V1> V2, the standard resistor Ro for measurement can be inserted into the electrical chassis with a high voltage (-), and then the both-end voltage V1 'can be measured.

5 (c), when V2 > V1, the standard resistance Ro can be measured by inserting the high voltage (+) into the electrical chassis and the both end voltage V2 '.

The insulation resistance values calculated through the measured voltage values (Vb, V1, V2, V1 'or V2') are as follows.

If V1 > V2, Ri = Ro * Vb * (1 / V1'-1 / V1).

If V2 > V1, then Ri = Ro * Vb * (1 / V2'-1 / V2).

R o is the standard resistance for measurement [Ω], and R i is the insulation resistance [Ω] of the vehicle.

The components or " units " or blocks or modules used in the present embodiment may be implemented in software such as a task, a class, a subroutine, a process, an object, an execution thread, , A field programmable gate array (FPGA), an application specific integrated circuit (ASIC), or a combination of the above software and hardware. The components or parts may be included in a computer-readable storage medium, or a part of the components may be dispersed in a plurality of computers.

As described above, the embodiments have been disclosed in the drawings and specification. Although specific terms are used herein, they are used for the purpose of describing the present invention only and are not used to limit the scope of the present invention described in the claims or the claims. It is therefore to be understood by those skilled in the art that various modifications and equivalent embodiments may be made without departing from the scope of the present invention. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

105: Control unit (FCU)
120: Stack voltage monitor unit (SVM)
140: Battery Management System (BMS)

Claims (10)

A method of measuring insulation resistance of a fuel cell vehicle,
The control unit controls the motor of the fuel cell vehicle Determining whether a DC link voltage supplied to the inverter is equal to or greater than a threshold voltage; And
When the DC link voltage is equal to or greater than the threshold voltage according to the determination result, the controller monitors the voltage of the fuel cell included in the fuel cell vehicle Transmitting an insulation resistance measurement command to the stack voltage monitoring unit for commanding insulation resistance measurement of the fuel cell vehicle
Wherein the insulation resistance of the fuel cell vehicle is measured.
The method of claim 1, wherein the insulation resistance of the fuel cell vehicle is measured by:
Wherein the control unit instructs the BMS to monitor the voltage of the battery included in the fuel cell vehicle when the DC link voltage is less than the threshold voltage, The method further comprising the step of transmitting an insulation resistance measurement command to the fuel cell vehicle.
3. The method of claim 2,
Wherein the threshold voltage is an operation voltage of the battery.
3. The method of claim 2,
Wherein the mode of the fuel cell vehicle when the DC link voltage is less than the threshold voltage includes an idle stop mode, an electric vehicle mode, or an downhill running mode. How to measure.
The method according to claim 1,
Wherein the insulation resistance is a resistance between a plus (+) high voltage terminal of the fuel cell connected to the inverter and a chassis ground included in the fuel cell vehicle or between a minus (-) high voltage terminal of the fuel cell connected to the inverter and the chassis ground Resistance of the fuel cell vehicle.
An apparatus for measuring insulation resistance of a fuel cell vehicle,
A controller for determining whether a DC link voltage supplied to an inverter for driving the motor of the fuel cell vehicle is equal to or greater than a threshold voltage; And
Monitoring the voltage of the fuel cell included in the fuel cell vehicle, and outputting, from the control unit, an insulation that instructs the insulation resistance measurement of the fuel cell vehicle when the DC link voltage is equal to or higher than the threshold voltage, A stack voltage monitor unit
And an insulation resistance measuring device for measuring the insulation resistance of the fuel cell vehicle.
7. The fuel cell vehicle according to claim 6,
Monitoring the voltage of the battery included in the fuel cell vehicle and instructing the control unit to measure the insulation resistance of the fuel cell vehicle when the DC link voltage is lower than the threshold voltage in accordance with the determination result Further comprising a battery management system (BMS) for receiving the battery.
8. The method of claim 7,
Wherein the threshold voltage is an operation voltage of the battery.
8. The method of claim 7,
Wherein the mode of the fuel cell vehicle when the DC link voltage is less than the threshold voltage includes an idle stop mode, an electric vehicle mode, or an downhill running mode. Measuring device.
The method according to claim 6,
Wherein the insulation resistance is a resistance between a plus (+) high voltage terminal of the fuel cell connected to the inverter and a chassis ground included in the fuel cell vehicle or between a minus (-) high voltage terminal of the fuel cell connected to the inverter and the chassis ground A device for measuring insulation resistance of a fuel cell vehicle including a resistor.

Images