CN112721640A - Active discharge control method for hydrogen fuel electric automobile - Google Patents
Active discharge control method for hydrogen fuel electric automobile Download PDFInfo
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- CN112721640A CN112721640A CN202011487882.0A CN202011487882A CN112721640A CN 112721640 A CN112721640 A CN 112721640A CN 202011487882 A CN202011487882 A CN 202011487882A CN 112721640 A CN112721640 A CN 112721640A
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- motor
- active discharge
- voltage
- measuring unit
- pwm
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- 229910052739 hydrogen Inorganic materials 0.000 title claims abstract description 38
- 239000001257 hydrogen Substances 0.000 title claims abstract description 38
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 title claims abstract description 37
- 239000000446 fuel Substances 0.000 title claims abstract description 23
- 238000000034 method Methods 0.000 title claims abstract description 21
- 239000003990 capacitor Substances 0.000 claims abstract description 32
- 238000012544 monitoring process Methods 0.000 claims abstract description 23
- 238000004804 winding Methods 0.000 claims abstract description 23
- 238000007599 discharging Methods 0.000 claims abstract description 18
- 230000005856 abnormality Effects 0.000 claims description 15
- 238000012545 processing Methods 0.000 claims description 15
- 230000002159 abnormal effect Effects 0.000 claims description 10
- 230000009467 reduction Effects 0.000 claims description 10
- 230000008569 process Effects 0.000 claims description 7
- 238000005259 measurement Methods 0.000 claims description 5
- 230000009286 beneficial effect Effects 0.000 abstract description 3
- 238000004146 energy storage Methods 0.000 description 4
- 230000007812 deficiency Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000003071 parasitic effect Effects 0.000 description 1
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- B60L3/00—Electric devices on electrically-propelled vehicles for safety purposes; Monitoring operating variables, e.g. speed, deceleration or energy consumption
- B60L3/0023—Detecting, eliminating, remedying or compensating for drive train abnormalities, e.g. failures within the drive train
- B60L3/0053—Detecting, eliminating, remedying or compensating for drive train abnormalities, e.g. failures within the drive train relating to fuel cells
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- B60L58/00—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles
- B60L58/30—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling fuel cells
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T90/00—Enabling technologies or technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02T90/40—Application of hydrogen technology to transportation, e.g. using fuel cells
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- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Sustainable Energy (AREA)
- Sustainable Development (AREA)
- Power Engineering (AREA)
- Transportation (AREA)
- Mechanical Engineering (AREA)
- Electric Propulsion And Braking For Vehicles (AREA)
Abstract
The invention provides a control method for active discharge of a hydrogen fuel electric automobile, which comprises the following steps: the device comprises an active discharge monitoring module, an IGBT module and a motor; two ends of the IGBT module are provided with high-voltage capacitors; the active discharging monitoring module is electrically connected with the IGBT module; the IGBT module is electrically connected with the motor; the active discharge monitoring module comprehensively monitors the PWM duty ratio of the IGBT module, the motor rotating speed, the motor winding current and the voltage drop rate of the high-voltage capacitor, so that the hydrogen energy automobile is in a safe state during active discharge. The beneficial effects provided by the invention are as follows: various signals of the hydrogen energy automobile active discharge are monitored by the monitoring module, so that the hydrogen energy automobile is in a safe state during active discharge.
Description
Technical Field
The invention relates to the field of automobile intelligent systems, in particular to a control method for active discharge of a hydrogen fuel electric automobile.
Background
In an electric automobile, an electric drive system mainly comprises a drive motor, a motor controller and energy storage equipment (a battery, a super capacitor and the like), wherein if the voltage of the energy storage equipment is usually more than several hundred volts, if the electric drive system needs to stop working, a high-voltage capacitor between direct current input ends of the motor controller can store certain electric quantity, according to the requirement of GB.T/18488, after the energy storage equipment is disconnected, the electric automobile needs to actively discharge the voltage at two ends of the high-voltage capacitor within 5s or passively discharge the voltage within 120s to be below a safe voltage, and the current active discharge mainly utilizes a DC/DC rectifier transformer or DC/AC. The controller outputs PWM (pulse width modulation) waveform to switch the DC/AC between the upper bridge arm short-circuit state and the lower bridge arm short-circuit state, and the energy on the high-voltage capacitor is consumed through the parasitic capacitor in the DC/AC, so that after the relay between the controller and the high-voltage energy storage device is disconnected, the voltage at two ends of the high-voltage capacitor is quickly reduced to be below the safe voltage. In the active discharging process, a power switch device inside the controller is always in a switch switching state, so that certain unsafe factors exist. For example, in order to ensure safety of the entire vehicle, it is necessary to monitor the active discharge period of the controller, such as an abnormal rotation speed, an abnormal torque, and a high-voltage discharge failure.
Disclosure of Invention
In view of the above, in order to solve the deficiencies in the prior art, the invention provides a method for controlling active discharge of a hydrogen-fueled electric vehicle, which monitors the active discharge period of a controller and provides safety of the entire vehicle during the active discharge period of the controller.
The invention provides a control method for active discharge of a hydrogen fuel electric automobile, which specifically comprises the following steps:
the device comprises an active discharge monitoring module, an IGBT module and a motor;
the active discharge monitoring module comprises a pulse width PWM measuring unit, a motor rotating speed measuring unit, a motor winding current measuring unit, a voltage drop rate measuring unit of a high-voltage capacitor and an exception handling unit;
the IGBT module consists of a 3-phase DC/AC inverter bridge, namely an A phase, a B phase and a C phase;
a high-voltage capacitor C1 is arranged at two ends of the IGBT module;
the active discharging monitoring module is electrically connected with the IGBT module;
the IGBT module is electrically connected with the motor;
the active discharge monitoring module comprehensively monitors the PWM duty ratio of the IGBT module, the motor rotating speed, the motor winding current and the voltage reduction rate of the high-voltage capacitor through the pulse width PWM measuring unit, the motor rotating speed measuring unit, the motor winding current measuring unit and the voltage reduction rate measuring unit of the high-voltage capacitor, and the hydrogen energy automobile is in a safe state during active discharge through the abnormality processing unit in an abnormal state.
Further, the measurement principle of the pulse width PWM measurement unit is:
monitoring the high level width of 3 paths of PWM waveforms output to an upper bridge arm or a lower bridge arm of a 3-phase DC/AC inverter bridge in each PWM period, monitoring the width of the PWM period, and finally calculating the duty ratio: duty ratio is high level width/cycle width; the duty ratio comprises 3 paths of PWMA、PWMBAnd PWMC。
Further, when the duty ratio of each of the 3 paths of duty ratios is within a preset interval [ a, b ] and the difference between any two paths of duty ratios is smaller than a preset value c, the hydrogen fuel vehicle actively discharges normally, otherwise, the abnormality processing unit controls the lower bridge arm of the 3-phase DC/AC inverter bridge to be in a short-circuit state, and the motor is safe.
Further, the motor rotating speed measuring unit measures the rotating speed of the motor in the active discharging process of the hydrogen fuel cell vehicle, if the rotating speed of the motor is smaller than a preset threshold value c, the active discharging of the hydrogen fuel cell vehicle is normal, otherwise, the active discharging of the hydrogen fuel cell vehicle is abnormal, and the abnormality processing unit controls a lower bridge arm of the 3-phase DC/AC inverter bridge to be in a short-circuit state, so that the motor is safe.
Further, the motor winding current measuring unit measures the motor winding current in the active discharging process of the hydrogen fuel cell vehicle, if the motor winding current is smaller than a preset threshold value d, it is indicated that the active discharging of the hydrogen fuel cell vehicle is normal, otherwise, it is indicated that the active discharging of the hydrogen fuel cell vehicle is abnormal, and the abnormality processing unit controls a lower bridge arm of the 3-phase DC/AC inverter bridge to be in a short-circuit state, so that the motor is safe.
The voltage drop rate measuring unit of the high-voltage capacitor measures the voltage at two ends of the high-voltage capacitor C1 in the active discharge process of the hydrogen fuel cell vehicle, if the voltage at two ends of the high-voltage capacitor C1 does not drop below a safe voltage within a preset time t, the abnormality is indicated, and the abnormality processing unit controls a lower bridge arm of a 3-phase DC/AC inverter bridge to be in a short-circuit state, so that the motor is safe.
The beneficial effects provided by the invention are as follows: various signals of the hydrogen energy automobile active discharge are monitored by the monitoring module, so that the hydrogen energy automobile is in a safe state during active discharge.
Drawings
FIG. 1 is a circuit diagram illustrating the control of the active discharge of a hydrogen fueled electric vehicle in accordance with the present invention;
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be further described with reference to the accompanying drawings.
Referring to fig. 1, a method for controlling active discharging of a hydrogen-fueled electric vehicle includes the following steps:
the device comprises an active discharge monitoring module, an IGBT module and a motor;
the active discharge monitoring module comprises a pulse width PWM measuring unit, a motor rotating speed measuring unit, a motor winding current measuring unit, a voltage drop rate measuring unit of a high-voltage capacitor and an exception handling unit;
the IGBT module consists of a 3-phase DC/AC inverter bridge, namely an A phase, a B phase and a C phase;
a high-voltage capacitor C1 is arranged at two ends of the IGBT module;
the active discharging monitoring module is electrically connected with the IGBT module;
the IGBT module is electrically connected with the motor;
the active discharge monitoring module comprehensively monitors the PWM duty ratio of the IGBT module, the motor rotating speed, the motor winding current and the voltage reduction rate of the high-voltage capacitor through the pulse width PWM measuring unit, the motor rotating speed measuring unit, the motor winding current measuring unit and the voltage reduction rate measuring unit of the high-voltage capacitor, and the hydrogen energy automobile is in a safe state during active discharge through the abnormality processing unit in an abnormal state.
The pulse width PWM measuring unit calculates the high level width of 3 paths of PWM waveforms output to a DC/AC upper bridge arm or a DC/AC lower bridge arm in each PWM period, calculates the PWM period width, transmits the high level width and the period width value of the 3 paths of PWM waveforms into an array in a memory at the end moment of each PWM period, and calculates the duty ratio in an interrupt program of each PWM period: the duty cycle is the high level width/period width, and the accuracy of the duty cycle depends on the time reference used to calculate the width.
After the active discharge monitoring module receives the DC/AC active discharge request signal and controls the PWM waveform generation module to enter an active discharge mode, if the duty ratios of 3 paths of PWM waveforms calculated by the pulse width measurement module are all about 50% (47% -53% all available) and the difference between every two duty ratios is close to 0 (the difference value is within 4%), the active discharge mode of the PWM waveform generation module is normal, otherwise, the DC/AC active discharge request is invalid, the abnormality processing unit controls the hydrogen energy automobile to actively discharge to enter a safety mode, and controls the DC/AC to enter a lower bridge arm short-circuit state, so that the safety of the motor is ensured.
Since one of the conditions of the DC/AC active discharge is the low rotating speed of the motor, whether the rotating speed of the motor is close to 0 needs to be monitored when the DC/AC active discharge is carried out; if the motor rotating speed measured by the motor rotating speed measuring unit is large (the motor rotating speed threshold can be set according to actual conditions), the abnormity processing unit controls the hydrogen energy automobile to actively discharge to enter a safety mode, and controls the DC/AC to enter a lower bridge arm short circuit state, so that the safety of the motor is ensured.
During the DC/AC active discharge period, the motor winding and the high voltage are disconnected, at the moment, the current in the motor winding is finally changed into 0, if the current in the motor winding measured by the motor winding current measuring unit during the DC/AC active discharge period is too large (a motor winding current threshold value can be set according to actual conditions), the DC/AC active discharge failure is indicated or the motor is likely to output unexpected torque, whether the current in the motor winding is close to 0 needs to be monitored during the DC/AC active discharge period, and if the current in the motor winding is too large, the abnormality processing unit controls the hydrogen energy automobile to actively discharge to enter a safety mode, controls the DC/AC to enter a lower bridge arm short-circuit state, and ensures the safety of the motor.
Because the DC/AC active discharge effect is that after the relay of the high-voltage battery is disconnected, the voltage at two ends of the high-voltage capacitor connected between the DC/AC direct-current ends is quickly reduced to be below the safe voltage, if the voltage at two ends of the high-voltage capacitor measured by the voltage reduction rate measuring unit of the high-voltage capacitor is not reduced to be below the safe voltage within the specified time, the DC/AC active discharge failure is indicated (the voltage at two ends of the high-voltage capacitor can be sampled by a hardware circuit, and whether the DC/AC active discharge is successful is monitored by judging whether the voltage reduction rate meets the requirement or not), if the voltage reduction rate at two ends of the high-voltage capacitor is not large (the voltage reduction rate of the high-voltage capacitor can be set according to the actual situation, the DC/AC active discharge failure is indicated, and the abnormity processing unit controls the hydrogen, and the DC/AC is controlled to enter a short-circuit state of a lower bridge arm, so that the safety of the motor is ensured.
The foregoing is illustrative of the present invention and is not to be construed as limiting thereof.
The beneficial effects provided by the invention are as follows: various signals of the hydrogen energy automobile active discharge are monitored by the monitoring module, so that the hydrogen energy automobile is in a safe state during active discharge.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.
Claims (6)
1. A control method for active discharge of a hydrogen fuel electric automobile is characterized by comprising the following steps: the method comprises the following steps:
the device comprises an active discharge monitoring module, an IGBT module and a motor;
the active discharge monitoring module comprises a pulse width PWM measuring unit, a motor rotating speed measuring unit, a motor winding current measuring unit, a voltage drop rate measuring unit of a high-voltage capacitor and an exception handling unit;
the IGBT module consists of a 3-phase DC/AC inverter bridge, namely an A phase, a B phase and a C phase;
a high-voltage capacitor C1 is arranged at two ends of the IGBT module;
the active discharging monitoring module is electrically connected with the IGBT module;
the IGBT module is electrically connected with the motor;
the active discharge monitoring module comprehensively monitors the PWM duty ratio of the IGBT module, the motor rotating speed, the motor winding current and the voltage reduction rate of the high-voltage capacitor through the pulse width PWM measuring unit, the motor rotating speed measuring unit, the motor winding current measuring unit and the voltage reduction rate measuring unit of the high-voltage capacitor, and the hydrogen energy automobile is in a safe state during active discharge through the abnormality processing unit in an abnormal state.
2. The method of claim 1 for controlling active discharge of a hydrogen-fueled electric vehicle, characterized in that:
the measurement principle of the pulse width PWM measurement unit is as follows:
monitoring the high level width of 3 paths of PWM waveforms output to an upper bridge arm or a lower bridge arm of a 3-phase DC/AC inverter bridge in each PWM period, monitoring the width of the PWM period, and finally calculating the duty ratio: duty ratio is high level width/cycle width; the duty ratio comprises 3 paths of PWMA、PWMBAnd PWMC。
3. The method of controlling active discharge of a hydrogen-fueled electric vehicle according to claim 2, characterized in that:
and when the duty ratio of each of the 3 paths of duty ratios is within a preset interval [ a, b ] and the difference between any two paths of duty ratios is smaller than a preset value c, the hydrogen fuel automobile actively discharges normally, otherwise, the hydrogen fuel automobile is abnormal, and the abnormality processing unit controls the lower bridge arm of the 3-phase DC/AC inverter bridge to be in a short-circuit state, so that the motor is safe.
4. The method of claim 1 for controlling active discharge of a hydrogen-fueled electric vehicle, characterized in that:
the motor rotating speed measuring unit measures the rotating speed of the motor in the active discharging process of the hydrogen fuel cell vehicle, if the rotating speed of the motor is smaller than a preset threshold value c, the active discharging of the hydrogen fuel cell vehicle is normal, otherwise, the active discharging of the hydrogen fuel cell vehicle is abnormal, and the abnormality processing unit controls a lower bridge arm of the 3-phase DC/AC inverter bridge to be in a short-circuit state, so that the motor is safe.
5. The method of claim 1 for controlling active discharge of a hydrogen-fueled electric vehicle, characterized in that: the motor winding current measuring unit measures the motor winding current in the active discharging process of the hydrogen fuel cell vehicle, if the motor winding current is smaller than a preset threshold value d, the active discharging of the hydrogen fuel cell vehicle is normal, otherwise, the active discharging of the hydrogen fuel cell vehicle is abnormal, and the abnormality processing unit controls a lower bridge arm of the 3-phase DC/AC inverter bridge to be in a short-circuit state, so that the motor is safe.
6. The method of claim 1 for controlling active discharge of a hydrogen-fueled electric vehicle, characterized in that: the voltage drop rate measuring unit of the high-voltage capacitor measures the voltage at two ends of the high-voltage capacitor C1 in the active discharge process of the hydrogen fuel cell vehicle, if the voltage at two ends of the high-voltage capacitor C1 does not drop below a safe voltage within a preset time t, the abnormality is indicated, and the abnormality processing unit controls a lower bridge arm of a 3-phase DC/AC inverter bridge to be in a short-circuit state, so that the motor is safe.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011487882.0A CN112721640A (en) | 2020-12-16 | 2020-12-16 | Active discharge control method for hydrogen fuel electric automobile |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011487882.0A CN112721640A (en) | 2020-12-16 | 2020-12-16 | Active discharge control method for hydrogen fuel electric automobile |
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| CN112721640A true CN112721640A (en) | 2021-04-30 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202011487882.0A Pending CN112721640A (en) | 2020-12-16 | 2020-12-16 | Active discharge control method for hydrogen fuel electric automobile |
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104626995A (en) * | 2013-11-06 | 2015-05-20 | 联合汽车电子有限公司 | High-voltage discharge system of electric vehicle |
| CN104638966A (en) * | 2013-11-06 | 2015-05-20 | 联合汽车电子有限公司 | Active discharge control system for electric car inverter and controller |
| CN109301889A (en) * | 2018-08-30 | 2019-02-01 | 深圳熙斯特新能源技术有限公司 | A kind of method of electric vehicle motor controller high-voltage capacitance repid discharge |
| CN111959278A (en) * | 2020-07-21 | 2020-11-20 | 一巨自动化装备（上海）有限公司 | Active turn-off control system and method for lower bridge arm of motor controller |
-
2020
- 2020-12-16 CN CN202011487882.0A patent/CN112721640A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104626995A (en) * | 2013-11-06 | 2015-05-20 | 联合汽车电子有限公司 | High-voltage discharge system of electric vehicle |
| CN104638966A (en) * | 2013-11-06 | 2015-05-20 | 联合汽车电子有限公司 | Active discharge control system for electric car inverter and controller |
| CN109301889A (en) * | 2018-08-30 | 2019-02-01 | 深圳熙斯特新能源技术有限公司 | A kind of method of electric vehicle motor controller high-voltage capacitance repid discharge |
| CN111959278A (en) * | 2020-07-21 | 2020-11-20 | 一巨自动化装备（上海）有限公司 | Active turn-off control system and method for lower bridge arm of motor controller |
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Application publication date: 20210430 |
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