CN114801874A - Electric vehicle pre-charging method - Google Patents
Electric vehicle pre-charging method Download PDFInfo
- Publication number
- CN114801874A CN114801874A CN202210467301.XA CN202210467301A CN114801874A CN 114801874 A CN114801874 A CN 114801874A CN 202210467301 A CN202210467301 A CN 202210467301A CN 114801874 A CN114801874 A CN 114801874A
- Authority
- CN
- China
- Prior art keywords
- voltage
- relay
- charging
- management system
- time period
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- 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
- B60L58/10—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries
-
- 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
Landscapes
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Sustainable Development (AREA)
- Sustainable Energy (AREA)
- Power Engineering (AREA)
- Transportation (AREA)
- Mechanical Engineering (AREA)
- Electric Propulsion And Braking For Vehicles (AREA)
- Charge And Discharge Circuits For Batteries Or The Like (AREA)
Abstract
The invention provides an electric automobile pre-charging method, which comprises the following steps: after receiving a high-voltage power-on request sent by a VCU of the vehicle control unit, the BMS controls a pre-charging relay to be closed and starts to pre-charge the power battery; after the power battery is precharged, if the difference value between the inner side voltage of the high-voltage relay and the outer side voltage of the high-voltage relay detected in a first preset time period is smaller than or equal to a first preset value, or the difference value between the inner side voltage of the high-voltage relay and the input end voltage input by the motor controller IPU detected in a second preset time period is smaller than or equal to a second preset value, the battery management system BMS controls the high-voltage relay to be closed so as to complete high-voltage electrification.
Description
Technical Field
The invention belongs to the field of new energy power batteries, and particularly relates to a method for pre-charging an electric vehicle based on total voltage collected by a Battery Management System (BMS) and voltage collected by an input end of a motor controller (IPU), so as to reduce the risk of unsuccessful high-voltage power-on caused by pre-charging failure of the electric vehicle.
Background
With the popularization of new energy automobiles and the strong support of the new energy automobile industry by the nation, the conservation quantity of new energy automobiles in the nation increases year by year. The electric automobile is powered by a power battery, and the power battery generally controls the power battery to output high voltage or cut off the high voltage through a relay. Each high-voltage load system of the electric vehicle generally adopts a capacitor to filter bus voltage, if the whole vehicle is electrified at high voltage, a high-voltage relay is directly closed, battery voltage is loaded at two ends of a load capacitor, the capacitor is charged by the voltage, unexpected large current is generated in the process, and components in a loop are damaged. To avoid the large current, the battery system needs to design a pre-charging loop, and the terminal voltage of the capacitor slowly rises to approach the total voltage of the battery system by using the RC charging characteristic.
The current mainstream electric vehicle pre-charging strategy mainly comprises the following steps: the battery management system BMS is used for collecting the voltages of the inner side and the outer side of the high-voltage relay of the power battery to compare, and when the voltage difference is smaller than the closing voltage which can be born by the relay, the high-voltage relay is closed. However, the scheme has certain defects, because the high-voltage bus outside the relay is connected with a whole vehicle high-voltage load loop, the whole vehicle high-voltage load has a plurality of parts, the control circuit of each part controller is lapped on the bus, and a battery management system BMS hardware developer cannot know the internal circuit composition of other controllers on the whole vehicle, so that a series of problems of interface matching, electromagnetic interference and the like can exist. The total voltage collection outside the high-voltage relay is influenced by an external circuit and is inaccurate in collection, and high-voltage power-on failure is caused. How to reduce and gather inaccurate because of battery management system BMS relay outside voltage receives the influence, leads to the unsuccessful risk of putting up electric in high pressure of whole car, becomes the problem that battery system development personnel need to solve urgently.
Disclosure of Invention
The invention aims to provide a method for pre-charging an electric vehicle based on total voltage collected by a battery management system BMS and voltage collected by an IPU input end of a motor controller, which can effectively reduce the risk of unsuccessful high-voltage electrification of the whole vehicle caused by the failure of pre-charging of the electric vehicle.
The technical scheme of the invention is as follows:
the invention provides an electric automobile pre-charging method, which comprises the following steps:
after receiving a high-voltage power-on request sent by a VCU of the vehicle control unit, the BMS controls a pre-charging relay to be closed and starts to pre-charge the power battery;
after the power battery is precharged, if the difference value between the inner side voltage of the high-voltage relay and the outer side voltage of the high-voltage relay detected in a first preset time period is smaller than or equal to a first preset value, or the difference value between the inner side voltage of the high-voltage relay and the input end voltage input by the motor controller IPU detected in a second preset time period is smaller than or equal to a second preset value, the battery management system BMS controls the high-voltage relay to be closed so as to complete high-voltage electrification.
Preferably, the method further comprises:
after the power battery is precharged, if the difference value between the inner side voltage of the high-voltage relay and the outer side voltage of the high-voltage relay detected in a first preset time period is larger than a first preset value or the difference value between the inner side voltage of the high-voltage relay and the input end voltage input by the IPU is larger than a second preset value detected in a second preset time period, the battery management system BMS does not control the high-voltage relay to be closed, and the precharge failure and the high-voltage electrifying failure are determined.
The invention has the beneficial effects that:
whether the conditions of high-voltage electrification are met or not is judged together through the voltage of the inner side and the outer side of a high-voltage relay of the power battery collected by a battery management system BMS and the voltage of a direct-current bus collected by an IPU (intelligent power unit). The motor controller IPU transmits the total input voltage to the battery management system BMS through the CAN bus, the battery management system BMS judges whether the voltage of the inner side of the high-voltage relay and the voltage of the outer side of the relay are lower than a certain value or whether the voltage of the inner side of the high-voltage relay and the voltage of the input end of the motor controller IPU are lower than a certain value in the pre-charging time, and if one of the two conditions is met, the high-voltage relay is closed, so that the pre-charging process is completed. By the adoption of the method for carrying out pre-charging judgment, detection on the voltage of the input end of the IPU is added, the probability of high-voltage power-on failure caused by inaccurate BMS acquisition due to the influence of an external circuit is successfully reduced, the redundancy and reliability of the system are improved, and the risks of pre-charging failure and high-voltage power-on failure of the electric vehicle are effectively reduced.
Drawings
Fig. 1 is a flow chart of pre-charging an electric vehicle based on total voltage collected by a battery management system BMS and voltage collected by an input terminal of an IPU of a motor controller according to the present invention;
fig. 2 is a schematic diagram of power battery pre-charging.
Detailed Description
In order that those skilled in the art will better understand the technical solution of the present invention, the following detailed description of the present invention is provided in conjunction with the accompanying drawings.
At present, the electric drive assembly possesses input voltage detection function as power battery output's receiving terminal usually, brings the input total voltage U3 that motor controller IPU gathered together with the high-voltage relay inboard voltage U1, the judgement of outside voltage U2 that battery management system BMS gathered into the precharge, can effectively reduce because of battery management system BMS relay outside voltage receives the influence and gathers inaccurately, leads to whole car high pressure to go up the unsuccessful risk.
Referring to fig. 1, the invention provides a method for pre-charging an electric vehicle based on total voltage collected by a battery management system BMS and voltage collected by an input end of a motor controller IPU, and mainly relates to three controllers of a vehicle control unit VCU, the battery management system BMS and the motor controller IPU.
After the initialization of the battery management system BMS is completed, the detection of the inner side voltage U1 and the outer side voltage U2 of the high-voltage relay is started, and after the motor controller IPU is awakened, the detection of the input end voltage U3 is started.
After the initialization of the VCU of the vehicle controller is completed, whether a key high-voltage power-on signal is received or not is judged, a high-voltage power-on request is sent to the battery management system BMS after the signal is received, the battery management system BMS closes a pre-charging relay to start pre-charging after receiving the voltage U3 at the input end of the IPU of the motor controller of the battery management system and the high-voltage power-on request of the VCU of the vehicle controller, and the BMS judges whether one of the following two conditions is met or not within a certain time period:
firstly, whether a difference value between an inner side voltage U1 and an outer side voltage U2 of the high-voltage relay, which is detected by a battery management system BMS, is less than or equal to a first preset value (the value depends on a maximum closing voltage difference value which can be borne by the high-voltage relay);
and secondly, whether the difference between the inner side voltage U1 of the high-voltage relay and the input end voltage U3 of the motor controller IPU is less than or equal to a second preset value (the value depends on the maximum closing voltage difference value which can be borne by the high-voltage relay).
If the voltage is met, the battery management system BMS closes the high-voltage relay, and high-voltage electrification is successful; if the voltage does not meet the preset voltage, the high-voltage relay is not closed, the pre-charging fails, and the high-voltage electrifying fails.
The invention judges whether the conditions of high-voltage electrification are met or not by adopting the power battery high-voltage relay inner side voltage U1 and outer side voltage U2 collected by a battery management system BMS and the direct current bus voltage U3 collected by a motor controller IPU. The motor controller IPU transmits the total input voltage to the battery management system BMS through the CAN bus, the battery management system BMS judges whether the inner side voltage U1 of the high-voltage relay and the outer side voltage U2 of the relay are lower than a certain value or whether the inner side voltage U1 of the high-voltage relay and the input end voltage U3 of the motor controller IPU are lower than a certain value in the pre-charging time, and if any one of the two conditions is met, the high-voltage relay is closed, and the pre-charging process is completed. By adopting the method to carry out the pre-charging judgment, the probability of high-voltage power-on failure caused by inaccurate BMS acquisition due to the influence of an external circuit is successfully reduced. The redundancy and the reliability of the system are improved, and the risks of failure of pre-charging and unsuccessful high-voltage power-on of the electric vehicle are effectively reduced.
Claims (2)
1. An electric vehicle pre-charging method is characterized by comprising the following steps:
after receiving a high-voltage power-on request sent by a VCU of the vehicle control unit, the BMS controls a pre-charging relay to be closed and starts to pre-charge the power battery;
after the power battery is precharged, if the difference value between the inner side voltage of the high-voltage relay and the outer side voltage of the high-voltage relay detected in a first preset time period is smaller than or equal to a first preset value, or the difference value between the inner side voltage of the high-voltage relay and the input end voltage input by the motor controller IPU detected in a second preset time period is smaller than or equal to a second preset value, the battery management system BMS controls the high-voltage relay to be closed so as to complete high-voltage electrification.
2. According to the electric automobile pre-charging method, the method is characterized by further comprising the following steps:
after the power battery is precharged, if the difference value between the inner side voltage of the high-voltage relay and the outer side voltage of the high-voltage relay detected in a first preset time period is larger than a first preset value or the difference value between the inner side voltage of the high-voltage relay and the input end voltage input by the IPU is larger than a second preset value detected in a second preset time period, the battery management system BMS does not control the high-voltage relay to be closed, and the precharge failure and the high-voltage electrifying failure are determined.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202210467301.XA CN114801874A (en) | 2022-04-29 | 2022-04-29 | Electric vehicle pre-charging method |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202210467301.XA CN114801874A (en) | 2022-04-29 | 2022-04-29 | Electric vehicle pre-charging method |
Publications (1)
Publication Number | Publication Date |
---|---|
CN114801874A true CN114801874A (en) | 2022-07-29 |
Family
ID=82510364
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN202210467301.XA Pending CN114801874A (en) | 2022-04-29 | 2022-04-29 | Electric vehicle pre-charging method |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN114801874A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN115635851A (en) * | 2022-10-31 | 2023-01-24 | 重庆长安新能源汽车科技有限公司 | Vehicle-mounted intelligent power distribution system, control method and storage medium |
-
2022
- 2022-04-29 CN CN202210467301.XA patent/CN114801874A/en active Pending
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN115635851A (en) * | 2022-10-31 | 2023-01-24 | 重庆长安新能源汽车科技有限公司 | Vehicle-mounted intelligent power distribution system, control method and storage medium |
CN115635851B (en) * | 2022-10-31 | 2024-06-04 | 深蓝汽车科技有限公司 | Vehicle-mounted intelligent power distribution system, control method and storage medium |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN107599857B (en) | Pure electric vehicle charging system and charging method based on lithium battery | |
CN109532494B (en) | High-voltage power-on control method and high-voltage power-off control method for pure electric vehicle | |
CN108790848B (en) | Ramp starting control system and method for fuel cell vehicle and vehicle | |
CN102837617B (en) | Power-off control method and device for high-voltage system of electric automobile | |
CN104935020B (en) | Wireless charging system and wireless charging method for electric automobile | |
CN112373320A (en) | BMS-based electric vehicle charging power-on control system and control method thereof | |
CN112924859B (en) | Electric automobile high-voltage pre-charging loop and relay adhesion state detection method | |
CN113619448A (en) | Intelligent monitoring method for new energy automobile storage battery | |
CN110406424A (en) | A kind of new-energy automobile power battery all the period of time monitoring system and method | |
CN114801874A (en) | Electric vehicle pre-charging method | |
CN111660963A (en) | Vehicle control unit integrating battery management system function and applied to low-speed electric vehicle | |
CN114013282B (en) | Whole-vehicle high-voltage power-on and power-off control method and control equipment for hydrogen fuel cell automobile | |
CN112572176A (en) | Control method for automatic restarting charging of vehicle-mounted charger | |
CN117607676A (en) | Relay adhesion detection method, circuit and vehicle | |
CN210706923U (en) | Sanitation vehicle | |
CN114236400B (en) | Power battery detection method and system and vehicle | |
CN116279219A (en) | New energy automobile storage battery electricity supplementing method and system | |
CN113071371B (en) | Electric automobile charging protection method and system | |
CN113602094A (en) | New energy automobile power-on method and device | |
CN110962785B (en) | Emergency power supply system and method for hydrogen energy automobile window | |
CN115001091A (en) | Automatic charging device and method for low-voltage battery pack of new energy automobile and new energy automobile | |
CN114559818A (en) | High-low voltage system, method for obtaining low voltage based on high voltage and electric automobile | |
CN111645565A (en) | Novel battery pack high-voltage control method | |
CN219927470U (en) | Novel new energy automobile power control system | |
CN205643646U (en) | Electric motor car and battery management device |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination |