CN112216558A - Relay drive circuit and electrical system - Google Patents
Relay drive circuit and electrical system Download PDFInfo
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- CN112216558A CN112216558A CN201910631604.9A CN201910631604A CN112216558A CN 112216558 A CN112216558 A CN 112216558A CN 201910631604 A CN201910631604 A CN 201910631604A CN 112216558 A CN112216558 A CN 112216558A
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- 238000003745 diagnosis Methods 0.000 claims description 28
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H47/00—Circuit arrangements not adapted to a particular application of the relay and designed to obtain desired operating characteristics or to provide energising current
- H01H47/22—Circuit arrangements not adapted to a particular application of the relay and designed to obtain desired operating characteristics or to provide energising current for supplying energising current for relay coil
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H47/00—Circuit arrangements not adapted to a particular application of the relay and designed to obtain desired operating characteristics or to provide energising current
- H01H47/002—Monitoring or fail-safe circuits
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Abstract
The invention provides a relay drive circuit and an electrical system, wherein the relay drive circuit comprises a power supply module, a control module, a high-side drive module and a low-side drive module, and the high-side drive module and the low-side drive module are connected in series and are respectively controlled by the control module, so that a high-side and low-side series drive mode of a relay is realized, and the problem of relay misoperation caused by the fact that the output end of the existing unilateral relay drive circuit which is driven by a single high-side switch or a single low-side switch has a short circuit or open circuit fault can be avoided.
Description
Technical Field
The invention relates to the technical field of electric automobile control, in particular to a relay drive circuit and an electrical system.
Background
The relay is an automatic switch element with an isolation function, is widely applied to remote control, remote measurement, communication, automatic control, electromechanical integration and power electronic equipment, and is one of the most important control elements. For example, with the development of automobile energy towards new energy, electric automobiles gradually become an important direction for the development of automobile technology, in the electric automobiles, the energy source of the automobiles mainly comes from a battery pack, and the connection between the battery pack and a high-voltage load is realized by taking a high-voltage relay as high-voltage connecting equipment for supplying power to high-voltage parts of the whole automobiles; in the existing battery system, the battery pack supplies power to a high-voltage load through unilateral control of a high-voltage relay, and particularly, the high-voltage relay is used as an important component of a new energy automobile and mainly used as a main positive relay, a main auxiliary relay, a positive relay and an auxiliary relay of a charging loop, a pre-charging relay for controlling pre-charging and the like of the battery pack, and the function and the safety performance of the high-voltage relay need to meet strict requirements.
The current main relay drive circuit uses a single high-side switch or a low-side switch to drive, namely the current relay drive circuit is usually a unilateral relay drive circuit, and the unilateral drive circuit structure easily causes malfunction of a high-voltage relay when the output end (namely, a high-side output pin) of the high-side switch is short-circuited to a power supply or the output end (namely, a low-side output pin) of the low-side switch is short-circuited to ground. In addition, when the conventional single-side driving circuit is applied to driving a high-voltage relay in an automobile, the faults that the output end of the high-side switch is short-circuited to a power supply, the output end of the low-side switch is short-circuited to the ground and the output end of the high-side switch or the low-side switch is open are not considered, and the diagnosis requirement of an automobile controller cannot be met. In addition, in the use process, the protection of the internal circuit and the load of the automobile controller under the condition of normal disconnection instant and fault is not considered in the conventional single-side driving circuit, and the single-side driving circuit is easy to fail under the long-term operation.
Disclosure of Invention
The invention aims to provide a novel relay drive circuit and an electrical system, which are used for avoiding the problem of relay misoperation when the output end of the conventional single-side relay drive circuit has short circuit or open circuit fault.
In order to solve the above technical problems, the present invention provides a relay driving circuit, which is connected to the positive terminal and the negative terminal of a control coil of a relay for driving the relay to be switched on or off, the relay driving circuit including a power module, and a control module, a high side driving module and a low side driving module which are respectively connected to the power module, wherein,
the control module is also connected with the high-side driving module and the low-side driving module and is used for providing a first control signal for the high-side driving module and providing a second control signal for the low-side driving module;
one input end of the high-side driving module is connected with the control module, the other input end of the high-side driving module is connected with the power supply module, and the output end of the high-side driving module is connected with the positive end of a control coil of the relay and is used for supplying voltage obtained from the power supply module to the relay under the control of a first control signal provided by the control module so as to drive the relay to be attracted or disconnected; and the number of the first and second groups,
the low-side driving module is connected with the high-side driving module in series, one input end of the low-side driving module is connected with the control module, and the output end of the low-side driving module is connected with the negative end of the control coil of the relay and used for directly outputting the voltage of the power module to supply power to the relay under the control of a second control signal provided by the control module so as to drive the relay to attract or break, or a path between the low-side driving module and the negative end of the control coil of the relay is switched on or off according to a set frequency and duty ratio so as to adjust and drive the equivalent voltage of the control coil of the relay to drive the relay to attract or break.
Optionally, the high-side driving module comprises: a control end of the high-side driving switch circuit is used as one input end of the high-side driving module and connected with one end of the control module, one end of a switch path of the high-side driving switch circuit is used as the other input end of the high-side driving module and connected with one ends of the power supply module and the low-side driving module, and the other end of the switch path of the high-side driving switch circuit is used as the output end of the high-side driving module and connected with the positive end of a control coil of the relay; and the output end of the clamping circuit is connected with the other end of the switch path of the high-side driving switch circuit and the positive end of the control coil of the relay, the input end of the clamping circuit is grounded and connected with the other end of the low-side driving module, and the clamping circuit is used for clamping the induced electromotive force on the control coil of the relay on a fixed voltage at the moment of disconnection of the relay so as to improve the disconnection speed of the relay.
Optionally, the high-side driving switch circuit includes a high-side MOS transistor having protection functions of overcurrent current limiting and over-temperature turn-off, where the MOS transistor is configured to limit a current flowing through an output terminal of the high-side driving module to a fixed value when the output terminal of the high-side driving module has a short-circuit fault, and automatically turn off when a temperature exceeds a set over-temperature threshold.
Optionally, the low-side driving module includes: a control end of the low-side driving switch circuit is used as an input end of the low-side driving module and connected with the other end of the control module, one end of a switch path of the low-side driving switch circuit is used as the other input end of the low-side driving module and is grounded and simultaneously connected with one end of the high-side driving module, and the other end of the switch path of the low-side driving switch circuit is used as the output end of the low-side driving module and is connected with the negative end of a control coil of the relay; and the input end of the follow current circuit is connected with one end of a switch path of the low-side driving switch circuit and the negative end of a control coil of the relay, the output end of the follow current circuit is connected with one end of the high-side driving module connected with the power module, and the follow current circuit is used for providing a follow current channel for the control coil of the relay in the stage that the low-side driving switch circuit is closed at the set frequency and duty ratio so as to ensure that the relay keeps a closed state.
Optionally, the low-side driving switch circuit includes an MOS transistor having protection functions of overcurrent limiting and over-temperature turn-off, and the MOS transistor is configured to limit a current flowing through the output terminal of the low-side driving module to a fixed value when the output terminal of the low-side driving module has a short-circuit fault, and is automatically turned off when the temperature exceeds a set over-temperature threshold.
Optionally, the first control signal is an on/off signal that directly controls a switching element in the high-side driving module to be turned on or off; the second control signal includes an on/off signal directly controlling the switching element in the low side driving module to be turned on or off and a PWM signal having the set frequency and duty ratio.
Optionally, the control module is configured to provide the on/off signal or the PWM signal to the low-side driving module as the second control signal according to a specific driving requirement and a driving condition of the relay.
Optionally, when the driving requirement requires that the voltage of the power supply module is directly supplied to a relay and the voltage of the power supply module is within an input voltage range allowed by a control coil of the relay, the control module outputs the on/off signal as the second control signal to be supplied to the low-side driving module; when the driving requirement requires that the voltage of the variable-voltage driving relay or the power supply module is higher than the maximum input voltage allowed by the control coil of the relay, the control module outputs the PWM signal to serve as the second control signal to be provided for the low-side driving module.
Optionally, the control module is further configured to control the outputs of the high-side driving module and the low-side driving module under a condition that the relay is turned off and when a single-point fault occurs on the circuit between the output end of the high-side driving module or the output end of the low-side driving module and the control coil, so that a voltage difference between a positive end and a negative end of the control coil of the relay is 0.
Optionally, the relay driving circuit further includes a diagnosis module, one sampling end of the diagnosis module is connected to the positive end of the control coil of the relay, the other sampling end of the diagnosis module is connected to the negative end of the control coil of the relay, the output end of the diagnosis module is connected to the control module, the diagnosis module is configured to monitor the positive end and the negative end of the control coil of the relay, and transmit monitored data back to the control module, so that the control module determines whether the relay fails according to the monitored data.
Optionally, the diagnostic module comprises: the high-side diagnostic circuit is used for monitoring the positive end of the control coil of the relay and transmitting monitored data back to the control module, so that the control module judges whether the positive end of the relay and the high-side driving module connected with the positive end have faults according to the monitored data; and one end of the low-side diagnostic circuit is used as a sampling end of the diagnostic module and connected with the negative end of the control coil of the relay, the other end of the low-side diagnostic circuit is used as an output end of the diagnostic module and connected with the control module, and the low-side diagnostic circuit is used for monitoring the negative end of the control coil of the relay and transmitting monitored data back to the control module, so that the control module judges whether the negative end of the relay and the low-side driving module connected with the negative end have faults or not according to the monitored data.
Optionally, the fault comprises at least one of a positive end of the control coil of the relay being shorted to a power source, a negative end of the control coil of the relay being shorted to ground, a positive end of the control coil of the relay being open, and a negative end of the control coil of the relay being open.
Optionally, when the first control signal is an on/off signal for directly controlling a switching element in the high-side driving module to be turned on or off, and the second control signal is an on/off signal for directly controlling a switching element in the low-side driving module to be turned on or off, the high-side diagnostic circuit samples a voltage at an output end of the high-side driving module or a voltage at a positive end of a control coil of the relay, and the low-side diagnostic circuit samples a voltage at an output end of the low-side driving module or a voltage at a negative end of the control coil of the relay; when the first control signal is an on/off signal for directly controlling the switching element in the high-side driving module to be turned on or off, and the second control signal is a PWM signal having the set frequency and duty ratio, the high-side diagnostic circuit samples the voltage of the output end of the high-side driving module or the voltage of the positive end of the control coil of the relay, and the low-side diagnostic circuit samples the frequency and duty ratio of the output signal of the output end of the low-side driving module.
Optionally, the power module comprises: the driving output power supply module is connected with the high-side driving module and the low-side driving module and is used for providing a driving power supply for the high-side driving module and the low-side driving module; and the internal circuit power supply module is connected with the control module and the diagnosis module and provides an internal circuit power supply for the control module and the diagnosis module.
Based on the same inventive concept, the invention further provides an electrical system, which comprises at least one relay and the relay driving circuit connected with the relay, wherein the relay driving circuit is connected with the positive end and the negative end of the control coil of the relay and used for driving the relay to be switched on or switched off.
Optionally, the electric system is for filling electric pile, automobile body controller, electric automobile battery management system, remote control equipment, telemetering measurement equipment, wireless communication equipment, pure electric vehicles or hybrid electric vehicles, and when the electric system is electric automobile battery management system, pure electric vehicles or hybrid electric vehicles, on-vehicle battery is connected to power module's input.
Compared with the prior art, the technical scheme of the invention has the following beneficial effects:
1. the high-side driving module and the low-side driving module are connected in series and controlled by the control module respectively, so that a high-side and low-side series driving mode of the relay can be realized, and the problem of relay misoperation caused by the fact that the output end of the existing unilateral relay driving circuit driven by a single high-side switch or a single low-side switch is short-circuited or open-circuited can be solved.
2. Further, the second control signal comprises an on/off (on/off) signal and a PWM signal, so that the relay driving circuit can be compatible with two driving modes of on/off (on/off) and PWM, and the driving requirement of the main high-voltage relay on the market is met.
3. Furthermore, the equivalent voltage of the control coil of the relay can be adjusted and driven in a PWM driving mode (namely, the equivalent output voltage of the low-side driving module is changed), and then the normal driving of the relay can be kept under the working condition that the voltage of the power supply module is higher than the maximum input voltage allowed by the control coil of the relay (for example, the working condition of overline starting), so that the relay is prevented from being damaged.
4. Furthermore, the clamping circuit is arranged in the high-side driving module, so that the high-side driving module and the low-side driving module can be connected in series, the relay can be rapidly turned off at the moment of switching off the relay, and the internal circuit structure of the relay driving circuit is protected from being damaged due to overlarge induced electromotive force in a control coil of the relay.
5. Further, the high-side driving module and/or the low-side driving module comprise MOS tubes with overcurrent limiting and over-temperature turn-off functions, so that when the output end of the high-side driving module or the low-side driving module breaks down, the internal circuit of the relay driving circuit, the relay and the external load connected with the relay are protected from being damaged due to overlarge current and overhigh temperature.
6. Furthermore, the relay driving circuit further comprises a diagnosis module, and can realize fault diagnosis of short circuit of the output end of the high-side driving module to the power supply, short circuit of the output end of the low-side driving module to the ground, open circuit of the output end of the high-side driving module and open circuit of the output end of the low-side driving module, so that the diagnosis requirements of electrical systems (or electrical products) such as automobile controllers are met.
Drawings
Fig. 1 is a schematic system structure diagram of a relay driving circuit according to an embodiment of the present invention;
FIG. 2 is a schematic circuit diagram of a high side driver module and a low side driver module according to an embodiment of the invention;
FIG. 3 is a schematic circuit diagram of a diagnostic module according to an embodiment of the present invention;
shown in the figure: 1-a power supply module; 11-a drive output power supply module; 12-internal circuit power supply module; 2-a control module; 21-a microcontroller; 22-peripheral circuitry; 3-high side driving module; 31-high side drive switch circuit; 32-a clamp circuit; 4-low side drive module; 41-low side drive switch circuit; 42-free-wheeling circuit; 5-a diagnostic module; 51-high side diagnostic circuitry; 52-low side diagnostic circuitry; 511-high side diagnostic network; 521-low-side diagnostic network; 512-high side voltage bias circuit; 522-low side voltage bias circuit; 6-control coil of relay; 61-positive terminal of control coil; 62-negative terminal of control coil; p1-high side output pin; p2-low side output pin.
Detailed Description
The relay driving circuit according to the present invention will be described in further detail with reference to the accompanying drawings and specific embodiments. Advantages and features of the present invention will become apparent from the following description and from the claims. It is to be noted that the drawings are in a very simplified form and are not to precise scale, which is merely for the purpose of facilitating and distinctly claiming the embodiments of the present invention.
The core idea of the invention is to provide a relay drive circuit to solve the problem that the malfunction of a relay is easily caused when the output pin (i.e. the output end) of the existing single-side drive circuit has a fault of short circuit to a power supply or short circuit to the ground.
Referring to fig. 1, an embodiment of the present invention provides a relay driving circuit, which is connected to a positive terminal 61 and a negative terminal 62 of a control coil 6 of a relay, for driving the relay (not shown) to be switched on or off. The relay driving circuit of the present embodiment includes a power module 1, a control module 2, a high-side driving module 3, a low-side driving module 4, and a diagnostic module 5. The power module 1 is respectively connected with the control module 2, the high-side driving module 3 and the diagnosis module 5 to supply power to the control module 2, the high-side driving module 3 and the diagnosis module 5, the control module 2 is also respectively connected with the high-side driving module 3, the low-side driving module 4 and the diagnosis module 5, and the high-side driving module 3 and the low-side driving module 4 are also connected in series. The relay is switched on when there is a voltage difference between the positive 61 and the negative 62 terminal which is not equal to 0, and the control coil 6 of the relay is switched off when the voltage difference between the positive 61 and the negative 62 terminal is equal to 0.
When the relay driving circuit of the embodiment is applied to an automobile, the input end of the power module 1 may be connected to a vehicle-mounted battery module.
Referring to fig. 1, in the present embodiment, the power module 1 includes a driving output power module 11 and an internal circuit power module 12. The driving output power supply 11 processes the power received by the power module 1 and outputs the processed power to the high-side driving module 2, and the processed power is used as a driving power UB of the high-side driving module 2 for driving the relay, and the driving power UB is provided for the low-side driving module 4 through the high-side driving module 2. The drive output power supply module 11 has the necessary power line protection devices including, but not limited to, anti-reverse diode, transient voltage suppression diode, and filter capacitor. The internal circuit power supply module 12 provides an internal circuit power (also referred to as an operating voltage, e.g., 5V or 3.3V) to the control module 2 and the diagnostic module 5, and typically includes a power regulation device such as a DC-DC voltage conversion circuit or a linear regulator (LDO) conversion circuit. As an example, the driving output power supply module 11 not only has a ceramic capacitor and a TVS tube for ESD and power line interference protection, but also has an electrolytic capacitor for filtering and voltage stabilizing, and further has a PMOS anti-reverse circuit for preventing reverse connection of an external power supply (for example, a battery) connected to the input terminal of the power supply module 1 from supplying power, so that the driving output power supply module 11 can realize safety protection of the relay driving power supply. As an example, the internal circuit power supply module 12 has a voltage conversion circuit such as a DC/DC circuit or an LDO circuit, and converts the voltage received by the input terminal of the power supply module 1 into an operating voltage required by the internal circuits of the control module 2 and the diagnostic module 5 by the voltage conversion circuit.
In this embodiment, the end of the driving power source UB is the positive electrode of the power source output by the driving output power supply module 11, and the ground GND is the negative electrode of the power source output by the driving output power supply module 11, which can be regarded as that the low-side driving module 4 also has one end directly connected to one output end of the driving output power supply module 11, and the driving output power supply module 11 directly supplies power to the low-side driving module 4.
With continued reference to fig. 1, the control module 2 includes a microcontroller 21 and a peripheral circuit 22, where the microcontroller 21 is connected to the high-side driving module 3 and the low-side driving module 4 through corresponding general purpose input/output (GPIO) interfaces to provide corresponding control signals to the high-side driving module 3 and the low-side driving module 4, so as to control the on and off of corresponding switching elements (e.g., MOS transistors) in the high-side driving module 3 and the low-side driving module 4, and further drive the relay to be activated or deactivated. The microcontroller 21 generates a first control signal and a second control signal according to specific relay driving requirements and driving conditions, wherein the first control signal is provided to the high-side driving module 3 through a first GPIO interface (not shown), and the second control signal is provided to the low-side driving module 4 through a second GPIO interface (not shown). Wherein, the first control signal is an On/off signal (defined as an On/off signal) for directly controlling the switching elements in the high-side driving module 3 to be turned On or off; the second control signal includes an On/off signal for directly controlling the switching elements in the low side driving module to be turned On or off and a PWM signal (i.e., a pulse width modulation signal) having the set frequency and duty ratio, so that the first control signal can control the switching elements in the high side driving module 3 to operate in an On/off form, and the second control signal can control the switching elements in the low side driving module 4 to operate in a PWM form. The two driving output modes of the On/off mode and the PWM mode can meet the driving requirements of different high-voltage relays, wherein when the microcontroller 21 outputs a second control signal of the On/off mode, a switch element in the low-side driving module 4 is always switched On, and directly outputs the voltage of the power module 1 (namely the voltage of an external power supply connected with the input end of the power module 1) to the control coil 6 of the relay so as to drive the relay to work; when the microcontroller 21 outputs the second control signal in PWM form, the switching element in the low-side driving module 4 is turned on and off at a set frequency and duty cycle, and the equivalent voltage of the control coil 6 of the driving relay can be conveniently adjusted. The low-voltage MOS tube is controlled to work in an On/off form or a PWM form according to specific high-voltage relay driving requirements and driving conditions. The peripheral circuit 22 may include functional circuits for implementing signal transmission and conversion between the microcontroller 21 and other modules such as the power supply module 1, the high-side driving module 3, the low-side driving module 4, and the diagnostic module 5, and may further include functional circuits for implementing functions different from those of the high-side driving module 3, the low-side driving module 4, and the diagnostic module 5, for example, for implementing functions of calculation, amplification, counting, synchronization, wireless communication, and the like.
In addition, it should be noted that the process of the microcontroller 21 generating the corresponding second control signal according to the specific relay driving requirement and driving condition includes: when the driving requirement requires to directly supply the voltage of the power module 1 (i.e. the voltage of the external power supply connected to the input end of the power module 1) to the relay and the voltage of the power module 1 (i.e. the voltage of the external power supply connected to the input end of the power module 1) is within the input voltage range allowed by the control coil 6 of the relay, the microcontroller 21 outputs a second control signal (i.e. an On/off signal) in an On/off form to be provided to the low-side driving module 4; when the driving requirement requires that the voltage for driving the relay or the power module 1 by transforming (i.e. the voltage of the external power source connected to the input terminal of the power module 1) is higher than the maximum input voltage allowed by the control coil 6 of the relay, the microcontroller 21 outputs a second control signal (i.e. a PWM signal) in a PWM form to the low-side driving module 4. Therefore, in a special working condition, when the voltage of the power module 1 (i.e. the voltage of the external power supply connected to the input end of the power module 1) is higher than the maximum voltage allowed to be input to the control coil 6 of the relay, the second control signal in the form of PWM can be used to enable the low-side driving module 4 to switch on or off the path between the low-side driving module and the negative end 62 of the control coil 6 of the relay at a set frequency and duty ratio, so as to adjust the equivalent voltage of the control coil 6 of the relay, and drive the relay to be switched on or off, thereby ensuring the normal operation of the relay.
Referring to fig. 1-2, the high-side driving module 3 includes a high-side driving switch circuit 31 and a clamping circuit 32. The control end of the high-side driving switch circuit 31 serves as an input end of the high-side driving module 3 and is connected with one end of the control module, one end of a switch path of the high-side driving switch circuit 31 serves as another input end of the high-side driving module 3 and is connected with the driving output power supply module 11 of the power module 1, and the other end of the switch path of the high-side driving switch circuit 31 serves as an output end of the high-side driving module 3 and is connected with a positive end 61 of a control coil 6 of the relay. The high-side driving switch circuit 31 is configured to provide the voltage obtained from the driving output power supply module 11 to the relay under the control of the first control signal provided by the microcontroller 21, so as to drive the relay to be switched on or switched off. The output end of the clamp circuit 32 is connected with the other end of the switch path of the high-side driving switch circuit 31 and the positive end 61 of the control coil 6 of the relay, the input end of the clamp circuit 32 is grounded and is simultaneously connected with one end of the low-side driving module 4, the clamp circuit 32 is used for realizing the series connection of the high-side driving module 3 and the low-side driving module 4, and at the moment of the disconnection of the relay, the induced electromotive force excited on the control coil 6 at the moment of the disconnection of the relay is limited, the energy is absorbed, the induced electromotive force on the control coil 6 of the relay is clamped on a fixed voltage, the current of the control coil 6 is rapidly reduced, the disconnection speed of the relay is improved, and the relay can be rapidly disconnected.
With continued reference to fig. 1-2, the low-side driving module 4 includes a low-side driving switch circuit 41 and a freewheeling circuit 42. The control terminal of the low side driving switch circuit 41 is used as one input terminal of the low side driving module 4 and connected to a second GPIO interface (not shown) of the microcontroller 21, one end of the switch path of the low side driving switch circuit 41 is used as the other input terminal of the low side driving module 4, and is grounded to GND and connected to one end of the clamping circuit 32, and the other end of the switch path of the low side driving switch circuit 41 is used as the output terminal of the low side driving module 4 and connected to the negative terminal 62 of the control coil 6 of the relay. The low-side driving switch circuit 41 is configured to directly output a voltage of the power module 1 (i.e., a voltage at which an input terminal of the power module 1 is connected to an external power source) to power the relay under the control of a second control signal provided by the microcontroller 21, so as to drive the relay to be switched on or switched off, or to switch on or off a path between the low-side driving switch circuit and a negative terminal of the control coil 6 of the relay at a set frequency and duty ratio, so as to adjust an equivalent voltage of the control coil 6 driving the relay, and drive the relay to be switched on or switched off. The input end of the free wheel circuit 42 is connected with one end of the switch path of the low-side driving switch circuit 41 and the negative end 62 of the control coil 6 of the relay, the output end of the free wheel circuit 42 is connected with one end of the high-side driving switch circuit 31 connected with the power module 1 (namely, one end of the high-side driving switch circuit 31 connected with the driving power supply UB), the free wheel circuit 42 is used for providing a free wheel channel for the control coil 6 of the relay in a stage that the low-side driving switch circuit 41 is closed at the set frequency and duty ratio (namely, in the period that the MOS transistor is closed in the PWM driving output), and the current for driving the control coil 6 of the relay is kept at the set average current so as to ensure that the relay is kept in the closed state.
The high-side driving switch circuit 31 and the low-side driving switch circuit 41 may be respectively mainly constructed by at least one MOS transistor. The clamping circuit 32 includes, but is not limited to, a transient suppression diode or a clamping structure of the high-side-drive switching circuit itself and other equivalent circuits, and the freewheeling circuit 42 may be implemented by a freewheeling diode, a freewheeling MOS transistor or other equivalent circuits.
As an example, the high-side drive switch circuit 31 and the low-side drive switch circuit 41 each have a MOS transistor, the clamp circuit 32 has a transient suppression diode, and the freewheel circuit 42 has a freewheel diode. The gate of the MOS transistor of the high-side driving switch circuit 31 is used as the control terminal of the high-side driving switch circuit 31, and is connected to a first GPIO interface (not shown) of the microcontroller 21, the drain of the MOS transistor of the high-side driving switch circuit 31 is used as one terminal of the switching path of the high-side driving switch circuit 31, and is simultaneously connected to the driving power source UB, the cathode of the first diode (not shown), and the cathode of the freewheeling diode of the freewheeling circuit 42, and the source of the MOS transistor of the high-side driving switch circuit 31 is used as the output terminal of the driving switch circuit 31 and the other terminal of the switching path of the high-side driving switch circuit 31, and is simultaneously connected to the positive terminal 61 of the control coil 6 of the relay, the anode of the first diode, and the cathode of the zener diode of the clamp circuit 32. The anode of the transient suppression diode of the clamp circuit 32 is grounded and connected to the source of the MOS transistor of the high-side drive switch circuit 31, the gate of the MOS transistor of the high-side drive switch circuit 31 is used as the control terminal of the low-side drive switch circuit 41 and connected to the second GPIO interface (not shown) of the microcontroller 21, the drain of the MOS transistor of the low-side drive switch circuit 41 is used as one terminal of the switching path of the low-side drive switch circuit 41, and the output terminal of the low-side switch circuit 41 is connected to the anode of the freewheeling diode, the cathode of the second diode (not shown) and the negative terminal 62 connected to the control coil 6 of the relay, and the source of the MOS transistor of the low-side drive switch circuit 41 is grounded as the other terminal of the switching path of the low-side drive switch circuit 41. Thus, the low voltage drive module 4 and the high voltage drive module 3 are connected in series.
In addition, when the relay drive circuit of the present embodiment is integrated as a chip, the output terminal of the high side drive switch circuit 31 may be formed as a high side output pin P1 for connecting the positive terminal 61 of the control coil 6 of the relay, and the output terminal of the low side drive switch circuit 41 may be formed as a low side output pin P2 for connecting the negative terminal 62 of the control coil 6 of the relay.
In addition, the MOS transistors in the high-side driving switch circuit 31 and the low-side driving switch circuit 41 are both intelligent MOS transistors and have functions of overcurrent current limiting and over-temperature turn-off, so that when short-circuit faults occur on the output pins P1 and P2, the current can be limited at a fixed value when the current is too large, the current of the control coil 6 of the relay is prevented from being too large, automatic turn-off can be guaranteed when the temperature of the MOS transistors exceeds an over-temperature threshold value, and the MOS transistors are protected from being damaged. That is, the MOS transistors with the functions of current limiting and over-temperature shutdown in the high-side driving switch circuit 31 and the low-side driving switch circuit 41 can limit the current flowing through the high-side output pin P1 and the low-side output pin P2 to a fixed value when the high-side output pin P1 and the low-side output pin P2 have a short-circuit fault, so as to avoid the problem that the driving current transmitted from the high-side driving switch circuit 31 and the low-side driving switch circuit 41 to the control coil of the relay is too large, and then the control coil 6 of the external relay is damaged by the excessive driving current and the MOS transistors themselves inside the high-side driving switch circuit 31 and the low-side driving switch circuit 41 are failed, and at the same time, the MOS transistors with the functions of current limiting and over-temperature shutdown in the high-side driving switch circuit 31 and the low-side driving switch circuit 41 have a short-circuit fault on the high-side output pin P1 and the low-side output pin P2, and the circuit can be automatically turned off when the temperature of the circuit exceeds a set over-temperature threshold value, so that the problems that the control coil 6 of an external relay is damaged due to over-high temperature in the circuit and MOS (metal oxide semiconductor) tubes in the high-side driving switch circuit 31 and the low-side driving switch circuit 41 are failed are solved.
In this embodiment, the high-side driving switch circuit 31 and the low-side driving switch circuit 41 cooperate to realize driving and controlling of the control coil 6 of the relay under the control of the microcontroller 21 of the control module 2. After the high-side driving module 3 and the low-side driving module 4 are connected in series, the high-side and low-side series driving can be performed on the control coil 6 of the relay, so that the problem that when a single output pin (P1 or P2) has a fault of being short-circuited to the ground or to the power supply, the control coil 6 of the relay is put between the positive terminal 61 and the negative terminal 62 and an unexpected voltage difference (for example, equal to the battery voltage of an external storage battery connected with the power supply module 1) is loaded, so that the relay malfunctions can be effectively avoided.
In addition, according to the driving requirement or different working condition requirements of the control coil 6, the first control signal and the second control signal generated by the control module 2 can enable the high-side driving switch circuit 31 and the low-side driving switch circuit 41 to work cooperatively, so as to control the control coil 6 of the relay to work in an on/off driving mode or a PWM driving mode. In both driving modes, the high-side driving switch circuit 31 is operated in an on/off state, and the low-side driving switch circuit 41 is operated in an on/off state or a PWM state, depending on whether the voltage of the power module 1 (i.e. the voltage of the external power source connected to the input terminal of the power module 1) is required to be directly supplied to the relay or whether the voltage of the power module 1 (i.e. the voltage of the external power source connected to the input terminal of the power module 1) is within an input voltage range allowed by the control coil 6 of the relay, when the voltage of the power module 1 (i.e. the voltage of the external power source connected to the input terminal of the power module 1) is required to be directly supplied to the relay and the voltage of the power module 1 (i.e. the voltage of the external power source connected to the input terminal of the power module 1) is within an input voltage range allowed by, the low side driving switch circuit 41 is operated in an on/off state, and when the voltage required to vary the voltage to drive the relay or the power module 1 (i.e., the voltage of the external power source connected to the input terminal of the power module 1) is higher than the maximum input voltage allowed by the control coil 6 of the relay, the low side driving switch circuit 41 is operated in a PWM state. In the PWM driving mode, the microcontroller 21 controls the side-driving switching circuit 41 to operate in the PWM state (i.e., output in the PWM mode at a set frequency and duty ratio) according to different driving conditions, so as to adjust the equivalent output voltage between the high-side output pin P1 and the low-side output pin P2, thereby implementing step-down output under the working conditions that the voltage of the power module 1 (i.e., the voltage of the external power source connected to the input terminal of the power module 1) is greater than the maximum input voltage allowed to be loaded by the control coil 6, and ensuring safe operation of the relay.
Referring to fig. 1 and 3, the diagnostic module 5 is capable of diagnosing at least one fault condition of the positive terminal 61 of the control coil 6 of the relay being shorted to the power module 1 (i.e., P1 being shorted to the power source), the negative terminal 62 of the control coil 6 of the relay being shorted to ground (i.e., P2 being shorted to the power source), the positive terminal 61 of the control coil 6 of the relay being open (i.e., P1 being open), and the negative terminal 62 of the control coil 6 of the relay being open (i.e., P2 being open), based on the diagnostic requirements. The diagnostic module 5 includes a high-side diagnostic circuit 51 and a low-side diagnostic circuit 52, the high-side diagnostic circuit 51 includes a high-side diagnostic network 511 and a high-side voltage dividing circuit 512, and the low-side diagnostic circuit 52 includes a low-side diagnostic network 521 and a low-side voltage dividing circuit 522.
Wherein, one end of the high-side diagnosis network 511 is used as a sampling end of the diagnosis module 5, is connected with the positive terminal 61 of the control coil 6 of the relay by connecting the high-side output pin P1, the other end of the high-side diagnostic network 511 is used as an output terminal of the diagnostic module 5, is connected with the sampling interface of the microcontroller 21 of the control module 2, the high-side diagnostic network 511 is used to monitor and sample the positive terminal 61 of the control coil 6 of the relay (i.e. the high-side output pin P1), and passes monitored and sampled data (including voltage information and signal state of the high-side output pin P1) back to (i.e. fed back to) the microcontroller 21 of the control module 2, so that the microcontroller 21 of the control module 2 determines from the monitored and sampled data whether the positive terminal 61 of the control coil 6 of the relay and the high side drive module 3 connected to the positive terminal 61 are malfunctioning. Specifically, the microprocessor 21 obtains the feedback information of the high-side diagnostic network 511 and the low-side diagnostic network 521 through the GPIO interface connected to the high-side diagnostic network 511, including the voltage of the high-side output pin P1 and the voltage information of the low-side output pin P2, and completes the fault diagnosis of the voltage of the high-side output pin P1 and the fault diagnosis of the low-side output pin P2 by combining the control states of the high-side drive module 3 and the low-side drive module 4.
The high-side voltage bias circuit 512 is connected with the positive terminal 61 of the control coil 6 of the relay and the high-side diagnostic network 511 by connecting the high-side output pin P1, the high-side voltage bias circuit 512 provides a fixed level and a voltage division network for the high-side output pin P1 when the high-side drive switch circuit 31 of the high-side drive module 3 is turned off (i.e., turned off), the voltage on the high-side output pin P1 is made to be in corresponding different voltage states under four different states of normal connection between the positive terminal 61 of the control coil 6 and the high-side output pin P1, short-circuit of the high-side output pin P1 to the power supply, short-circuit of the high-side output pin P1 to the ground and open circuit of the high-side output pin, and the high-side voltage bias circuit 512 can make the voltage on the high-side output pin P1 be in four voltage states in total.
One end of the low-side diagnostic network 521 is used as another sampling end of the diagnostic module 5, and is connected to the negative terminal 62 of the control coil 6 of the relay by connecting the low-side output pin P2, the other end of the low-side diagnostic network 521 is used as another output end of the diagnostic module 5, and is connected to a corresponding sampling interface of the microcontroller 21 of the control module 2, the low-side diagnostic network 521 is used for monitoring and sampling the negative terminal 62 (i.e. the low-side output pin P2) of the control coil 6 of the relay, and transmitting monitored and sampled data (including voltage information and signal state of the low-side output pin P2) back to the microcontroller 21 of the control module 2, so that the microcontroller 21 of the control module 2 judges whether the negative terminal 62 (i.e. the low-side output pin P2) of the control coil 6 of the relay and the low-side driving module 4 connected to the negative terminal 62 (i.e. the low-side output pin P2) occur or not according to the monitored and sampled data And (4) a barrier. Specifically, the microprocessor 21 obtains the feedback information of the high-side diagnostic network 511 and the low-side diagnostic network 521 through the GPIO interface connected to the low-side diagnostic network 511, including the voltage of the low-side output pin P1 and the voltage information of the low-side output pin P2, and completes the fault diagnosis of the voltage of the high-side output pin P1 and the fault diagnosis of the low-side output pin P2 by combining the control states of the high-side driving module 3 and the low-side driving module 4.
The low-side voltage bias circuit 522 is connected to the negative terminal 62 of the control coil 6 of the relay and the low-side diagnostic network 521 by connecting the low-side output pin P2, the low-side voltage bias circuit 522 provides a fixed level and a voltage dividing network for the low-side output pin P2 when the low-side driving switch circuit 41 of the low-side driving module 4 is turned off (i.e., turned off), the voltage on the low-side output pin P2 is made to assume corresponding different voltage states under four different states that the negative terminal 62 of the control coil 6 and the low-side output pin P2 are connected to be normal, the low-side output pin P2 is short-circuited to the power supply, the low-side output pin P2 is short-circuited to the ground, and the low-side output pin P2 is open-circuited, and the low-side voltage bias circuit 522 can make the voltage on the low-side output pin P2 assume four.
The high-side diagnostic network 511 and the low-side diagnostic network 521 connect the high-side output pin P1 and the low-side output pin P2 with corresponding GPIO ports of the microcontroller 21, so that the microcontroller 21 samples the voltages of the high-side output pin P1 and the low-side output pin P2. In the off state of the switching paths of the high-side driving module 3 and the low-side driving module 4, the microcontroller 21 samples the voltages of the high-side output pin P1 and the low-side output pin P2 through the high-side diagnostic network 511 and the low-side diagnostic network 521, compares the sampled voltages with a designed voltage range, diagnoses whether a fault exists on the high-side output pin P1 and the low-side output pin P2, and determines which fault is short-circuited to the power supply, short-circuited to the ground, or open-circuited.
Under the working condition that the relay is disconnected, if a single-point fault occurs on the high-side output pin P1 or the low-side output pin P2, under the control of the microcontroller 21, voltage is not applied to the positive end and the negative end of the relay control coil 6, the false operation of the relay is not caused, and the safety of load driving and the robustness of a system are improved. That is, the microcontroller 21 is further configured to control the outputs of the high-side driving module 3 and the low-side driving module 4 so that the voltage difference between the positive terminal 61 and the negative terminal 62 of the control coil 6 of the relay is 0 when the relay is in the off condition and a single-point fault occurs in the circuit between the output terminal of the high-side driving module 3 or the output terminal of the low-side driving module 4 and the control coil 6.
The high-side diagnostic network 511 and the low-side diagnostic network 521 both include an analog-to-digital conversion circuit and a filtering and voltage-stabilizing circuit. The analog-to-digital conversion circuit is used for sampling the voltage of the output pin by the microcontroller 21 and finishing fault diagnosis by combining a strategy, and the filtering and voltage stabilizing circuit can be an RC (resistance-capacitance) filtering circuit and is used for filtering and stabilizing the acquired voltage signal. Both the high side voltage bias circuit 512 and the low side voltage bias circuit 522 include voltage divider circuits, including but not limited to a form of resistive voltage division, that provide divided levels to the output pins P1 and P2.
In addition, since the low-side driving module 4 of this embodiment can implement On/off and PWM driving output modes to meet the driving requirements of different relays, in the On/off driving output mode, the high-side diagnostic network 511 samples the voltage of the high-side output pin P1, the low-side diagnostic network 521 samples the voltage of the low-side output pin P2, in the PWM driving output mode, the high-side diagnostic network 511 samples the voltage of the high-side output pin P1, and the low-side diagnostic network 521 samples the frequency and duty ratio of the signal at the low-side output pin P2.
Based on the same inventive concept, the present embodiment further provides an electrical system, where the electrical system includes at least one relay and the relay driving circuit according to the present invention connected to the relay, and the relay driving circuit is connected to the positive end and the negative end of the control coil of the relay to drive the relay to be switched on or off.
The electrical system can be at least one of remote control equipment, remote measuring equipment, communication equipment, automatic control equipment (including a vehicle body controller, an electric vehicle battery manager and the like), mechatronic equipment (including an electric vehicle and a charging pile) and mobile electronic equipment.
When electric system is electric automobile (being new energy automobile), it still includes battery package and high-pressure electric load, the battery package is vehicle-mounted battery promptly, connects relay drive circuit's power module 1's input, and the high-pressure electric load connects the contact of relay, the relay can be used as the main just and main auxiliary relay of battery package, charge circuit just, auxiliary relay and the pre-charge relay of control pre-charge.
In summary, in the relay driving circuit and the electrical system provided in this embodiment, the high-side driving module 3 and the low-side driving module 4 are turned on or off after receiving the control signal of the control module 2, so that a high-side and low-side series driving manner is realized, and a relay is driven to operate, thereby avoiding a problem that when a fault occurs in which the high-side output pin P1 is shorted to the power supply or the low-side output pin P2 is shorted to the ground, the current relay driving circuit is driven to perform single-side driving by using a single high-side switch or low-side switch, and the relay is likely to malfunction; moreover, on/off and PWM driving requirements can be compatible, so that the relay can be suitable for different application scenes, under two different driving modes, the voltages of the output pins of the high-side driving module 3 and the low-side driving module 4 are detected through the diagnosis module 5, whether the output pins of the high-side driving module 3 and the low-side driving module 4 are in fault or not is judged according to the detection result, the control module 2 controls the high-side driving module 3 and the low-side driving module 4 according to the judgment result to protect the relay, namely, fault diagnosis of the high-side output pin and the low-side output pin can be completed according to the feedback information of the diagnosis module, and the OBD diagnosis requirement of automobile application is met; under special working conditions (for example, under the condition that the voltage of the vehicle-mounted storage battery is higher than the maximum voltage allowed to be input by a control coil of the relay), the normal work of the relay is ensured by adopting a PWM equivalent voltage reduction mode. In addition, the relay driving circuit of the embodiment is provided with the high-side clamping circuit, so that the high-voltage relay can be ensured to be rapidly turned off at the moment of the disconnection of the relay, and the internal circuit structure is protected from being damaged due to overlarge induced electromotive force; the high-low side driving switch circuit has the functions of overcurrent current limiting and overtemperature turn-off, and ensures that when an output pin breaks down, the internal circuit and the external load are protected from being damaged due to overlarge current.
Obviously, the above embodiments have described the different configurations of the relay driving circuit in detail, and it goes without saying that the present invention includes but is not limited to the configurations listed in the above embodiments, and any modifications based on the configurations provided by the above embodiments are within the scope of protection of the present invention. One skilled in the art can take the contents of the above embodiments to take a counter-measure.
The above description is only for the purpose of describing the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention, and any variations and modifications made by those skilled in the art based on the above disclosure are within the scope of the appended claims.
Claims (16)
1. A relay drive circuit is connected with the positive end and the negative end of a control coil of a relay and is used for driving the relay to be attracted or disconnected, and is characterized in that the relay drive circuit comprises a power module, a control module, a high-side drive module and a low-side drive module, wherein,
the control module is also connected with the high-side driving module and the low-side driving module and is used for providing a first control signal for the high-side driving module and providing a second control signal for the low-side driving module;
one input end of the high-side driving module is connected with the control module, the other input end of the high-side driving module is connected with the power supply module, and the output end of the high-side driving module is connected with the positive end of a control coil of the relay and is used for supplying voltage obtained from the power supply module to the relay under the control of a first control signal provided by the control module so as to drive the relay to be attracted or disconnected; and the number of the first and second groups,
the low-side driving module is connected with the high-side driving module in series, one input end of the low-side driving module is connected with the control module, and the output end of the low-side driving module is connected with the negative end of the control coil of the relay and used for directly outputting the voltage of the power module to supply power to the relay under the control of a second control signal provided by the control module so as to drive the relay to attract or break, or a path between the low-side driving module and the negative end of the control coil of the relay is switched on or off according to a set frequency and duty ratio so as to adjust and drive the equivalent voltage of the control coil of the relay to drive the relay to attract or break.
2. The relay drive circuit of claim 1, wherein the high side drive module comprises:
a control end of the high-side driving switch circuit is used as one input end of the high-side driving module and connected with one end of the control module, one end of a switch path of the high-side driving switch circuit is used as the other input end of the high-side driving module and connected with one ends of the power supply module and the low-side driving module, and the other end of the switch path of the high-side driving switch circuit is used as the output end of the high-side driving module and connected with the positive end of a control coil of the relay; and the number of the first and second groups,
the output end of the clamping circuit is connected with the other end of the switch path of the high-side driving switch circuit and the positive end of the control coil of the relay, the input end of the clamping circuit is grounded and connected with the other end of the low-side driving module, and the clamping circuit is used for clamping the induced electromotive force on the control coil of the relay on a fixed voltage at the moment of disconnection of the relay so as to improve the disconnection speed of the relay.
3. The relay drive circuit as claimed in claim 2, wherein the high side driving switch circuit comprises a MOS transistor having protection functions of overcurrent limiting and overtemperature shutdown, the MOS transistor is configured to limit a current flowing through the output terminal of the high side driving module to a fixed value when a short-circuit fault occurs at the output terminal of the high side driving module, and is configured to automatically shutdown when the temperature exceeds a set overtemperature threshold.
4. The relay drive circuit of claim 1, wherein the low-side drive module comprises:
a control end of the low-side driving switch circuit is used as an input end of the low-side driving module and connected with the other end of the control module, one end of a switch path of the low-side driving switch circuit is used as the other input end of the low-side driving module and is grounded and simultaneously connected with one end of the high-side driving module, and the other end of the switch path of the low-side driving switch circuit is used as the output end of the low-side driving module and is connected with the negative end of a control coil of the relay; and the number of the first and second groups,
and the input end of the follow current circuit is connected with one end of a switch path of the low-side driving switch circuit and the negative end of the control coil of the relay, the output end of the follow current circuit is connected with one end of the high-side driving module connected with the power module, and the follow current circuit is used for providing a follow current channel for the control coil of the relay in the stage that the low-side driving switch circuit is closed at the set frequency and duty ratio so as to ensure that the relay keeps a closed state.
5. The relay driving circuit according to claim 4, wherein the low side driving switch circuit comprises an MOS transistor having protection functions of overcurrent limiting and over-temperature turning off, and the MOS transistor is used for limiting the current flowing through the output terminal of the low side driving module to a fixed value when the output terminal of the low side driving module has a short-circuit fault, and automatically turning off when the temperature exceeds a set over-temperature threshold value.
6. The relay drive circuit according to claim 1, wherein the first control signal is an on/off signal that directly controls a switching element in the high side drive module to be turned on or off; the second control signal includes an on/off signal directly controlling the switching element in the low side driving module to be turned on or off and a PWM signal having the set frequency and duty ratio.
7. The relay driver circuit according to claim 6, wherein the control module is configured to provide the on/off signal or the PWM signal to the low side driver module as the second control signal according to a specific driving requirement and driving condition of the relay.
8. The relay driver circuit according to claim 7, wherein when the driving demand requires the relay to be directly supplied with the voltage of the power supply module and the voltage of the power supply module is within an input voltage range allowed by a control coil of the relay, the control module outputs the on/off signal as the second control signal to be supplied to the low side driver module; when the driving requirement requires that the voltage of the variable-voltage driving relay or the power supply module is higher than the maximum input voltage allowed by the control coil of the relay, the control module outputs the PWM signal to serve as the second control signal to be provided for the low-side driving module.
9. The relay driver circuit according to claim 7, wherein the control module is further configured to control the outputs of the high-side driver module and the low-side driver module such that a voltage difference between a positive terminal and a negative terminal of the control coil of the relay is 0 when the relay is in an open condition and a single-point fault occurs on the circuit between the output terminal of the high-side driver module or the output terminal of the low-side driver module and the control coil.
10. The relay drive circuit according to any one of claims 1-9, further comprising a diagnostic module having one sampling terminal connected to the positive terminal of the control coil of the relay and the other sampling terminal connected to the negative terminal of the control coil of the relay, wherein the output terminal of the diagnostic module is connected to the control module, and the diagnostic module is configured to monitor the positive terminal and the negative terminal of the control coil of the relay and transmit monitored data back to the control module, so that the control module determines whether the relay is faulty according to the monitored data.
11. The relay drive circuit of claim 10, wherein the diagnostic module comprises:
the high-side diagnostic circuit is used for monitoring the positive end of the control coil of the relay and transmitting monitored data back to the control module, so that the control module judges whether the positive end of the relay and the high-side driving module connected with the positive end have faults according to the monitored data; and the number of the first and second groups,
the low-side diagnosis circuit is used for monitoring the negative end of the control coil of the relay and transmitting monitored data back to the control module, so that the control module judges whether the negative end of the relay and the low-side driving module connected with the negative end have faults or not according to the monitored data.
12. The relay drive circuit of claim 10, wherein the fault comprises at least one of a positive end of the control coil of the relay being shorted to a power source, a negative end of the control coil of the relay being shorted to ground, a positive end of the control coil of the relay being open, and a negative end of the control coil of the relay being open.
13. The relay driver circuit according to claim 10, wherein the first control signal is an on/off signal that directly controls the switching element in the high side driver module to be turned on or off, the second control signal is an on/off signal that directly controls the switching element in the low side driver module to be turned on or off, the high side diagnostic circuit samples a voltage of an output terminal of the high side driver module or a voltage of a positive terminal of a control coil of the relay, and the low side diagnostic circuit samples a voltage of an output terminal of the low side driver module or a voltage of a negative terminal of the control coil of the relay; when the first control signal is an on/off signal for directly controlling the switching element in the high-side driving module to be turned on or off, and the second control signal is a PWM signal having the set frequency and duty ratio, the high-side diagnostic circuit samples the voltage of the output end of the high-side driving module or the voltage of the positive end of the control coil of the relay, and the low-side diagnostic circuit samples the frequency and duty ratio of the output signal of the output end of the low-side driving module.
14. The relay drive circuit according to claim 10, wherein the power supply module includes:
the driving output power supply module is connected with the high-side driving module and the low-side driving module and is used for providing a driving power supply for the high-side driving module and the low-side driving module; and the number of the first and second groups,
and the internal circuit power supply module is connected with the control module and the diagnosis module and provides an internal circuit power supply for the control module and the diagnosis module.
15. An electrical system comprising at least one relay and a relay drive circuit according to any one of claims 1 to 14 connected to the relay, the relay drive circuit being connected to the positive and negative terminals of the control coil of the relay for actuating the relay to engage or disengage.
16. The electrical system of claim 15, wherein the electrical system is a charging pile, a body controller, an electric vehicle battery management system, a remote control device, a remote measurement device, a wireless communication device, a pure electric vehicle or a hybrid electric vehicle, and when the electrical system is an electric vehicle battery management system, a pure electric vehicle or a hybrid electric vehicle, the input end of the power module is connected to an on-board battery.
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113162147A (en) * | 2021-03-24 | 2021-07-23 | 浙江合众新能源汽车有限公司 | Bilateral-drive battery charging relay safety control system and method |
| CN113212247A (en) * | 2021-06-18 | 2021-08-06 | 中国第一汽车股份有限公司 | Management system and new energy automobile of power battery package |
| CN114783829A (en) * | 2022-05-07 | 2022-07-22 | 东软睿驰汽车技术（沈阳）有限公司 | Relay drive circuit and diagnosis method thereof |
| CN115248373A (en) * | 2021-04-27 | 2022-10-28 | 宁德时代新能源科技股份有限公司 | Relay adhesion detection method and device |
| WO2024006629A1 (en) | 2022-07-01 | 2024-01-04 | Caterpillar Inc. | Circuit to drive electrically controlled switches within an electrified machine |
| CN117595845A (en) * | 2023-11-21 | 2024-02-23 | 一汽解放汽车有限公司 | Driving circuit, control method and vehicle |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN203720299U (en) * | 2014-01-21 | 2014-07-16 | 浙江万向亿能动力电池有限公司 | Relay coil driving diagnosis device |
| CN108493904A (en) * | 2018-05-08 | 2018-09-04 | 上海金脉电子科技有限公司 | IGBT Safety Shutdown Systems and method for automobile motor shutdown |
| JP2019037079A (en) * | 2017-08-18 | 2019-03-07 | ローム株式会社 | Overcurrent protection circuit |
| CN109541457A (en) * | 2019-01-04 | 2019-03-29 | 中国第汽车股份有限公司 | Power battery high-voltage relay control circuit and method for diagnosing faults |
| CN109951060A (en) * | 2019-03-29 | 2019-06-28 | 西北工业大学 | High voltage half-bridge driving circuit |
-
2019
- 2019-07-12 CN CN201910631604.9A patent/CN112216558B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN203720299U (en) * | 2014-01-21 | 2014-07-16 | 浙江万向亿能动力电池有限公司 | Relay coil driving diagnosis device |
| JP2019037079A (en) * | 2017-08-18 | 2019-03-07 | ローム株式会社 | Overcurrent protection circuit |
| CN108493904A (en) * | 2018-05-08 | 2018-09-04 | 上海金脉电子科技有限公司 | IGBT Safety Shutdown Systems and method for automobile motor shutdown |
| CN109541457A (en) * | 2019-01-04 | 2019-03-29 | 中国第汽车股份有限公司 | Power battery high-voltage relay control circuit and method for diagnosing faults |
| CN109951060A (en) * | 2019-03-29 | 2019-06-28 | 西北工业大学 | High voltage half-bridge driving circuit |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113162147A (en) * | 2021-03-24 | 2021-07-23 | 浙江合众新能源汽车有限公司 | Bilateral-drive battery charging relay safety control system and method |
| CN115248373A (en) * | 2021-04-27 | 2022-10-28 | 宁德时代新能源科技股份有限公司 | Relay adhesion detection method and device |
| CN115248373B (en) * | 2021-04-27 | 2024-03-19 | 宁德时代新能源科技股份有限公司 | Relay adhesion detection method and device |
| CN113212247A (en) * | 2021-06-18 | 2021-08-06 | 中国第一汽车股份有限公司 | Management system and new energy automobile of power battery package |
| CN114783829A (en) * | 2022-05-07 | 2022-07-22 | 东软睿驰汽车技术（沈阳）有限公司 | Relay drive circuit and diagnosis method thereof |
| CN114783829B (en) * | 2022-05-07 | 2024-05-28 | 东软睿驰汽车技术（沈阳）有限公司 | Relay driving circuit and diagnosis method thereof |
| WO2024006629A1 (en) | 2022-07-01 | 2024-01-04 | Caterpillar Inc. | Circuit to drive electrically controlled switches within an electrified machine |
| CN117595845A (en) * | 2023-11-21 | 2024-02-23 | 一汽解放汽车有限公司 | Driving circuit, control method and vehicle |
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