CN113852277A - High-robustness DC/DC converter - Google Patents
High-robustness DC/DC converter Download PDFInfo
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- CN113852277A CN113852277A CN202110950930.3A CN202110950930A CN113852277A CN 113852277 A CN113852277 A CN 113852277A CN 202110950930 A CN202110950930 A CN 202110950930A CN 113852277 A CN113852277 A CN 113852277A
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/02—Conversion of dc power input into dc power output without intermediate conversion into ac
- H02M3/04—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters
- H02M3/06—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using resistors or capacitors, e.g. potential divider
- H02M3/07—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using resistors or capacitors, e.g. potential divider using capacitors charged and discharged alternately by semiconductor devices with control electrode, e.g. charge pumps
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
- H02H7/10—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers
- H02H7/12—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers for static converters or rectifiers
- H02H7/1213—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers for static converters or rectifiers for DC-DC converters
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/36—Means for starting or stopping converters
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- Power Engineering (AREA)
- Dc-Dc Converters (AREA)
- Charge And Discharge Circuits For Batteries Or The Like (AREA)
Abstract
The invention provides a high-robustness DC/DC converter, which ensures that the DC/DC converter can work under the condition as much as possible. The high-robustness DC/DC converter comprises: the device comprises an MCU controller, a pre-charging control module, an IGBT drive board, an IGBT and a power circuit; the IGBT driving board is provided with an IGBT driving circuit; in order to make the DC/DC converter have high robustness, firstly, in the aspect of circuit protection, a protection strategy with software as a main part and hardware as an auxiliary part is adopted; secondly, adopt neotype pre-charge circuit, only need a port control of controller, can realize the main relay automatic actuation in proper order after the pre-charge circuit pre-charge. In addition, a control method with high robustness is adopted, so that the functions of automatic starting, fault detection, fault recovery, hardware protection recovery and the like can be completed, and the DC/DC converter can work under the condition as far as possible.
Description
Technical Field
The present invention relates to a converter, and more particularly, to a DC/DC converter.
Background
The DC/DC converter is a voltage converter that effectively outputs a fixed voltage after converting an input voltage. DC/DC converters are divided into three categories: a step-up DC/DC converter, a step-down DC/DC converter, and a step-up/step-down DC/DC converter. Three types of control can be used as required: (1) PWM control type: the efficiency is high, and the output voltage ripple and the noise are good; (2) PFM control type: even if the device is used for a long time, the device has the advantage of low power consumption particularly under the condition of small load; (3) PWM/PFM conversion type: the PFM control is performed at a small load, and the PWM control is automatically switched to at a heavy load. DC/DC converters are widely used in products such as mobile phones, MP3, digital cameras, portable media players, and the like.
When designing a DC/DC converter, in order to avoid the internal self-damage, several protection measures are generally designed inside the DC/DC converter, which are taken to face various hazards, and the main protection of the internal design of the module is generally: input polarity protection, input undervoltage protection, input overvoltage protection, output short circuit protection, output overcurrent protection, output overvoltage protection, over-temperature protection and the like.
Generally, hardware protection is mostly adopted for a hardware-controlled DC/DC converter; and the DC/DC converter for controlling PWM wave generation by software is protected by collecting external AD data. However, if only software protection is adopted, when the program of the single chip microcomputer runs away, the program is out of control, and the protection effect cannot be achieved; and only adopt the control circuit of hardware protection, if voltage current collection is inaccurate, voltage current fluctuation can cause the spurious triggering to stop to generally can not resume after stopping, the robustness is relatively poor.
Before the DC/DC converter normally operates, in order to prevent overlarge current impact and overlarge voltage oscillation of the output side capacitor, the output side voltage-stabilizing capacitor needs to be pre-charged through the pre-charging circuit, and the pre-charging circuit has the function of effectively protecting the output side capacitor, a safety device and a direct current contactor, so that the situation that the charging current is possibly overlarge at the moment of direct power-on, the capacitor is possibly damaged due to overlarge instantaneous current, and the direct current contactor and other switching devices are also damaged is prevented.
As shown in fig. 1, the conventional precharge circuit includes: a pre-charging resistor (i.e. a pre-charging resistor) and a pre-charging contactor, wherein the pre-charging contactor is used for controlling the opening and closing of the pre-charging loop, and the pre-charging resistor is used for limiting the current. The pre-charging contactor and the pre-charging resistor are connected in series and then connected in parallel with the main contactor. During pre-charging, the main relay is firstly disconnected, a pre-charging loop formed by the pre-charging contactor, the pre-charging resistor and the battery is firstly connected to charge the output side capacitor (namely the load shown in fig. 1), and the main contactor is controlled to be closed after the set time. The control method has risks, for example, the pre-charging contactor is not closed, and the main contactor is closed by error control; or after the pre-charging contactor is closed, the time for closing the main contactor is too short, and the capacitor charging faults can be caused, so that hidden dangers are caused.
Disclosure of Invention
In view of the above, the present invention provides a highly robust DC/DC converter, which ensures that the DC/DC converter can operate under the condition as much as possible.
The high-robustness DC/DC converter comprises: the device comprises an MCU controller, a pre-charging control module, an IGBT drive board, an IGBT and a power circuit; the IGBT driving board is provided with an IGBT driving circuit;
the precharge control module includes: a pre-charge relay K1, a pre-charge relay K2 and a pre-charge resistor R1; the main relay of the DC/DC converter is a main relay K3;
one control port of the MCU controller is connected with the control end of the pre-charging relay K1;
the execution end of the pre-charging relay K1 is arranged between the low-voltage battery and the control end of the pre-charging relay K2;
the pre-charging resistor R1 and the execution end of the pre-charging relay K2 are connected in series and then connected in parallel with the execution end of the main relay K3, and then the whole pre-charging relay is arranged between the high-voltage input and the high-voltage output of the DC/DC converter;
the low-voltage battery is connected with the control end of a main relay K3 through an RC delay circuit, the RC delay circuit comprises a resistor R2 and a capacitor C1, wherein the resistor R2 is connected with the control end of the main relay K3 in series, and the capacitor C1 is connected with the control end of the main relay K3 in parallel; the rear end of the control end of the pre-charging relay K2 is connected with a capacitor C1.
As a preferred embodiment of the present invention: when the pre-charging is started, the MCU controller sends an attraction signal to the control end of the pre-charging relay K1 to control the actuation end of the pre-charging relay K1 to attract;
if the external manual switch is in a closed state at the moment, the pre-charging relay K2 is electrified and attracted, the capacitor C1 starts to charge, and when the voltage of the capacitor C1 is increased to the opening voltage of the main relay K3, the main relay K3 is attracted.
As a preferred embodiment of the present invention: the input polarity protection, the input undervoltage protection, the input overvoltage protection, the output overcurrent protection and the over-temperature protection of the DC/DC converter adopt software protection; the output overvoltage protection and the output current-limiting protection adopt hardware protection and are realized by an overvoltage protection circuit and a current-limiting protection circuit;
through the collection that software protection signal was carried out to the MCU controller includes: the temperature acquisition device comprises an input voltage value, an output current value and a set temperature value of a temperature acquisition point;
meanwhile, the MCU controller is used for receiving an external on-off instruction so as to control the DC/DC converter to be on or off; after the DC/DC converter is started, if the DC/DC converter is shut down under the condition that the MCU controller does not receive a shutdown instruction, the MCU controller is automatically started after the set time.
As a preferred embodiment of the present invention: an external manual switch is arranged between the low-voltage battery and an execution end of the pre-charging relay K1, and after the external manual switch is turned off, the high-voltage input of the DC/DC converter is cut off.
As a preferred embodiment of the present invention: a test point is arranged between the control end of the pre-charging relay K2 and the execution end of the pre-charging relay K1 and is used for detecting whether the pre-charging relay K1 is attracted or not and judging whether an external manual switch is in a switch-on state or not;
and feeding back the test signal of the test point to the MCU controller.
As a preferred embodiment of the present invention: the control logic of the DC/DC converter is as follows:
after the low-voltage battery supplies power to the MCU controller, the MCU controller enters the following circulation:
the method comprises the following steps: information acquisition: the MCU controller firstly acquires an input voltage value, an output current value and a temperature value and performs filtering processing on acquired data;
step two: undervoltage protection:
the MCU controller firstly carries out input under-voltage judgment according to the acquired input voltage value, if no under-voltage fault is input, a corresponding fault mark is cleared, and the step III is directly carried out; if the input voltage value is smaller than the undervoltage set value, disconnecting the pre-charging relay K1, stopping driving the IGBT, juxtaposing the undervoltage fault flag as 1, and entering the third step; if the input voltage exceeds the set under-voltage point, clearing the under-voltage fault mark, and then entering the step three;
step three: detecting input overvoltage, output overvoltage or output overcurrent faults:
the MCU controller respectively judges input overvoltage, output overvoltage and output overcurrent according to the acquired input voltage value, output voltage value and output current value, if the faults do not exist, corresponding fault marks are cleared, and the step IV is directly carried out; if an input overvoltage, an output overvoltage or an output overcurrent fault exists, stopping driving the IGBT, juxtaposing a corresponding fault mark as 1, and entering the fourth step; if the input overvoltage, the output overvoltage or the output overcurrent detection returns to normal, clearing the corresponding fault mark, and then entering the fourth step;
step four: and (3) over-temperature protection:
the MCU controller carries out over-temperature judgment according to the acquired temperature value, if the temperature is lower than the set temperature, the fault mark is cleared, and the step five is directly carried out; if the over-temperature fault exists, stopping driving the IGBT, setting the over-temperature fault mark as 1, and entering the fifth step; if the temperature detection is recovered to normal, the fault mark is cleared, and then the step five is carried out;
step five: timing power-on/power-off control:
detecting an external power on/off instruction, and if the external power on/off instruction exists, acting according to the external power on/off instruction;
if the MCU controller does not receive a shutdown instruction and the DC/DC converter is shut down, delaying for setting time, if the MCU controller does not receive a startup instruction after the delay is finished, controlling the equipment to be automatically started by the MCU controller, namely, the MCU controller sends a pre-charging instruction to the pre-charging control module, and after the pre-charging of the capacitor C1 is finished, the main relay K3 is attracted to drive the IGBT and the DC/DC converter starts to work;
when the DC/DC converter works normally, if the output voltage is smaller than a set voltage value and the output current is smaller than a set value, the DC/DC converter is considered to trigger hardware protection or abnormal shutdown, the main relay K3 is disconnected, the IGBT is stopped to be driven, the abnormal shutdown frequency is added by 1, and a timing automatic starting program is waited to be performed; otherwise, entering the next cycle;
and if the abnormal shutdown times are larger than the set times, the operation is stopped, the DC/DC converter cannot work continuously, and the fault state is not cleared.
Has the advantages that:
(1) in order to make the DC/DC converter have high robustness, firstly, in the aspect of circuit protection, a protection strategy with software as a main part and hardware as an auxiliary part is adopted; secondly, adopt neotype pre-charge circuit, only need a port control of controller, can realize the main relay automatic actuation in proper order after the pre-charge circuit pre-charge. In addition, the control method with high robustness is adopted, so that the functions of automatic starting, fault detection, fault recovery, hardware protection recovery and the like can be completed, and the DC/DC converter can be ensured to work under the condition as far as possible (namely, the DC/DC converter can be ensured to work under the working condition).
(2) The DC/DC converter is provided with an external manual switch for emergency stop of equipment, the high-voltage side input of the DC/DC converter can be cut off after the external manual switch is disconnected, and power generation can be continued after the external manual switch is closed.
Drawings
FIG. 1 is a schematic diagram of a pre-charging circuit of a prior art DC/DC converter;
FIG. 2 is a schematic diagram of the connection of the high robustness DC/DC converter of the present invention in the circuit system;
FIG. 3 is an internal structural view of the high robustness DC/DC converter of the present invention;
FIG. 4 is a schematic diagram illustrating the protection of the hardware and software of the high-robustness DC/DC converter according to the present invention;
FIG. 5 is a schematic diagram of a high robustness DC/DC converter pre-charge control module of the present invention;
FIG. 6 is a flow chart of the operation of the pre-charge control module;
fig. 7 is a flow chart of the operation of the high-robustness DC/DC converter of the present invention.
Detailed Description
The present invention is described in detail below with reference to the attached drawings and preferred embodiments so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making the scope of the present invention more clearly and clearly defined.
The embodiment provides a safe and reliable DC/DC converter with excellent robustness.
As shown in fig. 2, the DC/DC converter is connected to a high-voltage battery, a low-voltage battery and a low-voltage load, respectively, when in use, wherein the low-voltage battery (usually 28V) and the low-voltage load (i.e. the electrical device) are connected to the same bus bar, and the low-voltage battery is used for supplying power to the electrical device before the DC/DC converter is not operated; when the high-voltage battery supplies power, the DC/DC converter has input to charge the low-voltage battery and supply power to the low-voltage load.
As shown in fig. 3, the DC/DC converter is internally provided with: the device comprises an MCU controller, a pre-charging control module, an IGBT drive board, an IGBT and a power circuit; the IGBT driving board is provided with an IGBT driving circuit;
the MCU controller is used for the collection of circuit protection signal, and its AD signal of gathering includes: the temperature acquisition device comprises an input voltage value, an output current value and a set temperature value of a temperature acquisition point; meanwhile, the MCU controller is used for receiving an external power on/off instruction and pre-charging control module state acquisition; the input voltage value and the output voltage value are collected for input under-voltage protection, input overvoltage protection and output overvoltage protection; collecting an output current value for outputting overcurrent protection; and collecting a temperature value for over-temperature protection. The state collection of the pre-charging control module is used for emergency stop of equipment, when the condition signal of the pre-charging control module is collected to judge that the equipment cannot be normally stopped, an external manual switch in the pre-charging control module is turned off, the high-voltage input end is cut off at the moment, and the DC/DC converter stops working. The power on/off instruction is used for controlling the DC/DC converter to be powered on/off, and after the DC/DC converter is powered on, if the DC/DC converter is powered off under the condition that the MCU controller does not receive the power off instruction, the MCU controller can be automatically started after the set time (10S is set here), so that the normal work of the rear-end electric equipment is ensured.
The pre-charging control module is used for pre-charging the whole equipment before the DC/DC converter works normally, and the IGBT works again after the pre-charging is finished; and after the pre-charging is finished, when the normal working condition is met, the MCU controller sends PWM waves to the IGBT driving circuit, the IGBT driving circuit drives the IGBT, and then the power circuit is controlled, so that the DC/DC converter works normally.
Before the DC/DC converter does not output, 28V voltage output by the low-voltage battery is converted into 5V voltage through voltage conversion and then supplies power for the MCU controller for equipment initialization; when the DC/DC converter has output, the voltage output by the DC/DC converter is converted by voltage to supply power for the MCU controller, and meanwhile, the output of the DC/DC converter charges a low-voltage battery.
As shown in fig. 4, in terms of device protection, the DC/DC converter adopts a protection strategy with software as a main component and hardware as an auxiliary component; the software protection comprises the following steps: input polarity protection, input undervoltage protection, input overvoltage protection, output overcurrent protection, output overvoltage protection and over-temperature protection (namely, the protection is realized by a software program, and a MCU controller acquires corresponding AD signals); the most important output overvoltage protection and current-limiting protection functions are still stored in hardware (namely, the output overvoltage protection function is realized through an overvoltage protection circuit, and the current-limiting protection function is realized through a current-limiting protection circuit); when software fails or programs run away, the hardware protection circuit can protect the software, and irreversible hardware damage is avoided.
As shown in fig. 5, the pre-charge control module can be controlled by only one control port of the MCU controller, so that the main relay of the DC/DC converter can be automatically closed after the pre-charge circuit is pre-charged. The precharge control module includes: a pre-charge relay K1, a pre-charge relay K2 and a pre-charge resistor R1; the main relay of the DC/DC converter is main relay K3. One control port of the MCU controller is connected with the control end of the pre-charging relay K1 and is used for controlling the pre-charging relay K1 to be switched on and off; an actuating terminal (i.e., a switch portion) of the pre-charge relay K1 is provided between the low-voltage battery and the control terminal of the pre-charge relay K2, and an external manual switch is provided between the low-voltage battery and the actuating terminal of the pre-charge relay K1, whereby the pre-charge relay K1 serves to control the closing and opening of the circuit between the low-voltage battery and the control terminal of the pre-charge relay K2. The pre-charging resistor R1 and the execution end of the pre-charging relay K2 are connected in series and then connected in parallel with the execution end of the main relay K3, and then are integrally arranged between a high-voltage input end and a high-voltage output end (the high-voltage output end is the high-voltage battery input end of the DC/DC converter). The low-voltage battery is connected with the control end of the main relay K3 after passing through an RC delay circuit (comprising a resistor R2 and a capacitor C1) (wherein the resistor R2 is connected with the control end of the main relay K3 in series, and the capacitor C1 is connected with the control end of the main relay K3 in parallel); the rear end of the control end of the pre-charging relay K2 is connected with a capacitor C1.
As shown in fig. 6, the working principle of the precharge control module is as follows: when the pre-charging is started, the MCU controller sends an attraction signal to the control end of the pre-charging relay K1 to control the actuation end of the pre-charging relay K1 to attract; if the external manual switch is in a closed state, the pre-charging relay K2 is immediately powered on and attracted, so that the pre-charging resistor R1 is connected in parallel to a loop, and meanwhile, the large-capacity capacitor C1 starts to be charged, and the voltage at the rear end of the pre-charging relay K2 cannot change suddenly due to the existence of the capacitor C1; after the time is set, when the voltage of the capacitor C1 is increased to the starting voltage of the main relay K3, the main relay K3 is attracted, so that the pre-charging relay K2 and the main relay K3 are ensured to be closed in sequence, and the problems of pre-charging time and sequence possibly caused by the fact that the pre-charging relay K2 and the main relay K3 are respectively controlled by the two ports can be avoided due to the fact that the pre-charging time is a constant value (namely the charging time of the capacitor C1).
The external manual switch is used for emergency stop of equipment, when the external manual switch is switched off, the pre-charging relay K2 and the main relay K3 cannot supply power, the high-voltage input is switched off, and the DC/DC converter stops working.
A test point is arranged between the execution end of the pre-charging relay K1 and the control end of the pre-charging relay K2 and is used for collecting the state of a pre-charging control module; the level (represented by 0 or 1) between the test point and the ground is measured, and the level is used for detecting whether the actuating end of the pre-charging relay K1 is attracted or not and also used for judging whether the external manual switch is in a connection state or not. If the external manual switch is in an off state after the pre-charging relay K1 is attracted, the pre-charging relay K2 and the main relay K3 cannot be closed, and the low level is fed back to the MCU controller through the test point.
For the control logic, the control method with high robustness as shown in fig. 7 is adopted, so that the functions of automatic starting, fault detection, fault recovery, hardware protection recovery and the like can be completed, and the DC/DC converter can be ensured to work under the condition as far as possible. The specific control method comprises the following steps:
after the low-voltage battery supplies power to the MCU controller, the MCU controller starts to enter the following circulation after the system is initialized:
the method comprises the following steps: information acquisition: the MCU controller firstly acquires an input voltage value, an output current value and a temperature value and carries out filtering processing on acquired data.
Step two: undervoltage protection:
the MCU controller firstly carries out input undervoltage judgment according to the acquired input voltage value, if no undervoltage fault is input (namely the input voltage exceeds an undervoltage set value), a corresponding fault mark is cleared, and the step III is directly carried out; if the input voltage value is smaller than the undervoltage set value, disconnecting the pre-charge relay K1, stopping sending PWM waves to the IGBT driving circuit, juxtaposing the undervoltage fault mark as 1, and entering the third step; on the one hand, undervoltage protection is performed, and on the other hand, after the high-voltage input voltage is cut off, the precharge relay K1 is turned off so that the precharge operation can be performed again after the next power-on. If the input voltage exceeds the set under-voltage point (i.e. under-voltage recovery), the under-voltage fault flag is cleared, and then the step three is performed.
Step three: detecting input overvoltage, output overvoltage or output overcurrent faults:
the MCU controller respectively judges input overvoltage, output overvoltage or output overcurrent according to the acquired input voltage value, output voltage value and output current value, if the faults do not exist, corresponding fault marks are cleared, and the step IV is directly carried out; if the input overvoltage, the output overvoltage or the output overcurrent fault exists, stopping sending the PWM wave to the IGBT driving circuit, juxtaposing a corresponding fault mark as 1, and entering the fourth step; the pre-charging relay K1 is not disconnected, so that the service life of the pre-charging relay K1 is prolonged, the next starting is facilitated, and the starting time is shortened; if the input overvoltage, the output overvoltage or the output overcurrent detection returns to normal, clearing the corresponding fault mark, and then entering the fourth step;
step four: and (3) over-temperature protection:
the MCU controller carries out over-temperature judgment according to the acquired temperature value, if the temperature is lower than the set temperature (set to be 100 ℃), the fault mark is cleared, and the step five is directly carried out; and if the over-temperature fault exists, stopping sending the PWM wave to the IGBT driving circuit, and if the over-temperature fault exists, juxtaposing that the over-temperature fault mark is 1 and entering the step five. If the temperature detection is recovered to be normal and is lower than the set temperature, the fault mark is cleared, and then the step five is carried out.
Step five: timing power-on/power-off control:
detecting an external power on/off instruction, and if the external power on/off instruction exists, acting according to the external power on/off instruction;
if the MCU controller is shut down under the state that the shutdown instruction is not received, the time is set in a delay setting mode (set to 10S here), if the MCU controller does not receive the startup instruction after the delay is finished, the MCU controller controls the equipment to be started, namely, the MCU controller sends a pre-charging instruction to the pre-charging control module, after the pre-charging of the capacitor C1 is finished, the main relay K3 is attracted, the high-low state of a test point in the pre-charging control module is detected, if the low state is detected, the pre-charging relay K1 is damaged or an external manual switch is not closed, the PWM wave needs to be stopped being sent to the IGBT driving circuit, and therefore the situation that the pre-charging relay K1 or the external manual switch is suddenly closed to damage the relay is avoided. If the pre-charging relay K1 works normally, after waiting for a period of time, PWM waves are sent to the IGBT driving circuit, and the DC/DC converter starts to work.
Hardware failure/other unknown failure: when the DC/DC converter works normally (namely temperature value, input voltage and output current are all normal), if the output voltage is smaller than a set voltage value and the output current is smaller than a set value, the DC/DC converter is considered to trigger hardware protection or abnormal shutdown, a main relay K3 and an IGBT (hardware fault can be cleared) are disconnected, the number of times of the abnormal shutdown is automatically increased by 1, and a timing automatic starting program is waited to be carried out; otherwise, the next cycle is entered.
If the number of times of abnormal shutdown is more than the set limit times by adding 1, the operation is stopped, the problem belongs to a hardware fault, the DC/DC converter cannot work continuously, and the fault state is not cleared.
Note that:
when the current limiting protection in the hardware protection cannot perform current limiting, the overcurrent protection of software faults can only work, so that the hardware current limiting value is smaller than the software overcurrent protection value. The overvoltage protection value of the hardware is preferably higher than the overvoltage protection value of the software, the voltage AD in the software is compared after being filtered, and hardware filtering can be added into a hardware circuit.
The undervoltage protection needs to close the pre-charging relay K1, and input overvoltage, output overvoltage or output overcurrent faults are not needed, because the input capacitor stores electricity as long as the input voltage does not fall down to an undervoltage protection point.
The protection temperature set value of the temperature protection should be higher than the recovery value, otherwise the temperature will be rapidly increased as soon as the temperature recovers to generate power immediately, and the temperature protection is triggered again in such a bad cycle.
In the control of the timing startup/shutdown machine, after a pre-charge relay K1 attracting instruction is issued, the state of a pre-charge relay K1 needs to be detected, if the pre-charge relay K1 does not attract normally, an external manual switch is probably not closed, at the moment, the sending of PWM waves to an IGBT driving circuit is stopped, after the external manual switch is closed, the attracting state of the relay K1 can be obtained immediately, the IGBT is turned on in a delayed mode (the PWM waves are sent to the IGBT driving circuit), and power generation is continued. In the process, a pre-charge relay K1 attracting command is issued firstly, because the test point cannot be measured to obtain a true value when the pre-charge relay K1 is not attracted.
In the whole process, after the input voltage is undervoltage, a command for closing the pre-charging relay K1 is issued.
The software high-voltage collecting point is collected at the input side of the DC/DC converter, namely the front ends of the pre-charging relay K2 and the main relay K3.
The above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (6)
1. A highly robust DC/DC converter comprising: the device comprises an MCU controller, a pre-charging control module, an IGBT drive board, an IGBT and a power circuit; the IGBT driving board is provided with an IGBT driving circuit; the method is characterized in that:
the precharge control module includes: a pre-charge relay K1, a pre-charge relay K2 and a pre-charge resistor R1; the main relay of the DC/DC converter is a main relay K3;
one control port of the MCU controller is connected with the control end of the pre-charging relay K1;
the execution end of the pre-charging relay K1 is arranged between the low-voltage battery and the control end of the pre-charging relay K2;
the pre-charging resistor R1 and the execution end of the pre-charging relay K2 are connected in series and then connected in parallel with the execution end of the main relay K3, and then the whole pre-charging relay is arranged between the high-voltage input and the high-voltage output of the DC/DC converter;
the low-voltage battery is connected with the control end of a main relay K3 through an RC delay circuit, the RC delay circuit comprises a resistor R2 and a capacitor C1, wherein the resistor R2 is connected with the control end of the main relay K3 in series, and the capacitor C1 is connected with the control end of the main relay K3 in parallel; the rear end of the control end of the pre-charging relay K2 is connected with a capacitor C1.
2. The highly robust DC/DC converter of claim 1, wherein: when the pre-charging is started, the MCU controller sends an attraction signal to the control end of the pre-charging relay K1 to control the actuation end of the pre-charging relay K1 to attract;
if the external manual switch is in a closed state at the moment, the pre-charging relay K2 is electrified and attracted, the capacitor C1 starts to charge, and when the voltage of the capacitor C1 is increased to the opening voltage of the main relay K3, the main relay K3 is attracted.
3. The highly robust DC/DC converter of claim 1, wherein: the input polarity protection, the input undervoltage protection, the input overvoltage protection, the output overcurrent protection and the over-temperature protection of the DC/DC converter adopt software protection; the output overvoltage protection and the output current-limiting protection adopt hardware protection and are realized by an overvoltage protection circuit and a current-limiting protection circuit;
through the collection that software protection signal was carried out to the MCU controller includes: the temperature acquisition device comprises an input voltage value, an output current value and a set temperature value of a temperature acquisition point;
meanwhile, the MCU controller is used for receiving an external on-off instruction so as to control the DC/DC converter to be on or off; after the DC/DC converter is started, if the DC/DC converter is shut down under the condition that the MCU controller does not receive a shutdown instruction, the MCU controller is automatically started after the set time.
4. A highly robust DC/DC converter as claimed in claim 1, 2 or 3, characterized in that: an external manual switch is arranged between the low-voltage battery and an execution end of the pre-charging relay K1, and after the external manual switch is turned off, the high-voltage input of the DC/DC converter is cut off.
5. The highly robust DC/DC converter according to claim 4, wherein: a test point is arranged between the control end of the pre-charging relay K2 and the execution end of the pre-charging relay K1 and is used for detecting whether the pre-charging relay K1 is attracted or not and judging whether an external manual switch is in a switch-on state or not;
and feeding back the test signal of the test point to the MCU controller.
6. The highly robust DC/DC converter of claim 1, wherein: the control logic of the DC/DC converter is as follows:
after the low-voltage battery supplies power to the MCU controller, the MCU controller enters the following circulation:
the method comprises the following steps: information acquisition: the MCU controller firstly acquires an input voltage value, an output current value and a temperature value and performs filtering processing on acquired data;
step two: undervoltage protection:
the MCU controller firstly carries out input under-voltage judgment according to the acquired input voltage value, if no under-voltage fault is input, a corresponding fault mark is cleared, and the step III is directly carried out; if the input voltage value is smaller than the undervoltage set value, disconnecting the pre-charging relay K1, stopping driving the IGBT, juxtaposing the undervoltage fault flag as 1, and entering the third step; if the input voltage exceeds the set under-voltage point, clearing the under-voltage fault mark, and then entering the step three;
step three: detecting input overvoltage, output overvoltage or output overcurrent faults:
the MCU controller respectively judges input overvoltage, output overvoltage and output overcurrent according to the acquired input voltage value, output voltage value and output current value, if the faults do not exist, corresponding fault marks are cleared, and the step IV is directly carried out; if an input overvoltage, an output overvoltage or an output overcurrent fault exists, stopping driving the IGBT, juxtaposing a corresponding fault mark as 1, and entering the fourth step; if the input overvoltage, the output overvoltage or the output overcurrent detection returns to normal, clearing the corresponding fault mark, and then entering the fourth step;
step four: and (3) over-temperature protection:
the MCU controller carries out over-temperature judgment according to the acquired temperature value, if the temperature is lower than the set temperature, the fault mark is cleared, and the step five is directly carried out; if the over-temperature fault exists, stopping driving the IGBT, setting the over-temperature fault mark as 1, and entering the fifth step; if the temperature detection is recovered to normal, the fault mark is cleared, and then the step five is carried out;
step five: timing power-on/power-off control:
detecting an external power on/off instruction, and if the external power on/off instruction exists, acting according to the external power on/off instruction;
if the MCU controller does not receive a shutdown instruction and the DC/DC converter is shut down, delaying for setting time, if the MCU controller does not receive a startup instruction after the delay is finished, controlling the equipment to be automatically started by the MCU controller, namely, the MCU controller sends a pre-charging instruction to the pre-charging control module, and after the pre-charging of the capacitor C1 is finished, the main relay K3 is attracted to drive the IGBT and the DC/DC converter starts to work;
when the DC/DC converter works normally, if the output voltage is smaller than a set voltage value and the output current is smaller than a set value, the DC/DC converter is considered to trigger hardware protection or abnormal shutdown, the main relay K3 is disconnected, the IGBT is stopped to be driven, the abnormal shutdown frequency is added by 1, and a timing automatic starting program is waited to be performed; otherwise, entering the next cycle;
and if the abnormal shutdown times are larger than the set times, the operation is stopped, the DC/DC converter cannot work continuously, and the fault state is not cleared.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114683854A (en) * | 2022-04-15 | 2022-07-01 | 北京新能源汽车股份有限公司 | Electric vehicle control method, device and equipment |
| CN115765082A (en) * | 2022-11-15 | 2023-03-07 | 北京航天发射技术研究所 | Pre-charging control method and device for synchronous servo controller of special equipment |
| CN114683854B (en) * | 2022-04-15 | 2024-06-11 | 北京新能源汽车股份有限公司 | Electric automobile control method, device and equipment |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080185999A1 (en) * | 2007-02-06 | 2008-08-07 | Panasonic Ev Energy Co., Ltd. | Power supply device |
| JP2009153274A (en) * | 2007-12-19 | 2009-07-09 | Sanyo Electric Co Ltd | Vehicular power supply unit |
| DE102014219211A1 (en) * | 2014-09-23 | 2016-03-24 | Robert Bosch Gmbh | Electric actuator with preheating |
| CN106230057A (en) * | 2016-08-18 | 2016-12-14 | 西北工业大学 | The precharge of a kind of converter and error protection integrated apparatus |
| DE102019110063A1 (en) * | 2018-05-24 | 2019-11-28 | Toyota Jidosha Kabushiki Kaisha | A vehicle power supply device and method for controlling a vehicle power supply device |
-
2021
- 2021-08-18 CN CN202110950930.3A patent/CN113852277B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080185999A1 (en) * | 2007-02-06 | 2008-08-07 | Panasonic Ev Energy Co., Ltd. | Power supply device |
| JP2009153274A (en) * | 2007-12-19 | 2009-07-09 | Sanyo Electric Co Ltd | Vehicular power supply unit |
| DE102014219211A1 (en) * | 2014-09-23 | 2016-03-24 | Robert Bosch Gmbh | Electric actuator with preheating |
| CN106230057A (en) * | 2016-08-18 | 2016-12-14 | 西北工业大学 | The precharge of a kind of converter and error protection integrated apparatus |
| DE102019110063A1 (en) * | 2018-05-24 | 2019-11-28 | Toyota Jidosha Kabushiki Kaisha | A vehicle power supply device and method for controlling a vehicle power supply device |
Non-Patent Citations (1)
| Title |
|---|
| 滕世国: "一种具有预充电"软启动"整流的大电流低电压电源", 《轻工科技》, vol. 37, no. 07 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114683854A (en) * | 2022-04-15 | 2022-07-01 | 北京新能源汽车股份有限公司 | Electric vehicle control method, device and equipment |
| CN114683854B (en) * | 2022-04-15 | 2024-06-11 | 北京新能源汽车股份有限公司 | Electric automobile control method, device and equipment |
| CN115765082A (en) * | 2022-11-15 | 2023-03-07 | 北京航天发射技术研究所 | Pre-charging control method and device for synchronous servo controller of special equipment |
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|---|---|
| CN113852277B (en) | 2023-11-07 |
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