CN214380636U

CN214380636U - Auxiliary source monitoring circuit and vehicle-mounted charger

Info

Publication number: CN214380636U
Application number: CN202120002940.XU
Authority: CN
Inventors: 冯颖盈; 姚顺; 冯仁伟; 刘剑
Original assignee: Shenzhen Vmax Power Co Ltd
Current assignee: Shenzhen Vmax Power Co Ltd; Shenzhen VMAX New Energy Co Ltd
Priority date: 2021-01-04
Filing date: 2021-01-04
Publication date: 2021-10-08
Anticipated expiration: 2031-01-04

Abstract

The utility model discloses an auxiliary source monitoring circuit and a vehicle-mounted charger, wherein the auxiliary source monitoring circuit comprises a high-power switch tube module, a high-voltage battery, an internal auxiliary source module, a signal control module, an isolation driving module, an isolation auxiliary source module and an auxiliary source monitoring module; the internal auxiliary source module supplies power to the signal control module; the signal control module generates a PWM driving signal; the isolation driving module is used for isolating and amplifying the PWM driving signal and then driving the high-power switching tube module; the isolation auxiliary source module supplies power to the isolation driving module; the auxiliary source monitoring module collects power supply signals of the output end of the external low-voltage power supply G and the output end of the internal auxiliary source module C, and controls whether the signal control module continues to output PWM driving signals or not according to the level change of the power supply signals; the utility model discloses can monitor inside auxiliary source module and isolation auxiliary source module, guarantee that the vehicle charger can in time cut off the control signal of high-power switch pipe when the external power supply is unusual.

Description

Auxiliary source monitoring circuit and vehicle-mounted charger

Technical Field

The utility model relates to a charge and electricity drive field, mainly be an auxiliary source monitoring circuit and vehicle charger.

Background

With the requirements of energy conservation and emission reduction and air pollution control, new energy automobiles are gradually commercialized in the market, and electric automobiles are more the main force of the new energy automobiles. With the wide application of new energy vehicles, the safety and reliability of the vehicle-mounted charger used as a new energy vehicle becomes a focus of more and more attention. The high-power switching tube is used as a main application device of the vehicle-mounted charger, and is a device which is mainly possible to fail due to the fact that the application of the high-power switching tube is sensitive to power supply voltage. Therefore, the requirements for monitoring the power supply voltage of the high-power switching tube and protecting the whole system are particularly urgent.

SUMMERY OF THE UTILITY MODEL

In order to solve the above-mentioned defect that exists among the prior art, the utility model provides an auxiliary source monitoring circuit and vehicle charger.

The utility model adopts the technical scheme that an auxiliary source monitoring circuit is designed, which comprises a high-power switch tube module connected with an external high-voltage power supply, a high-voltage battery receiving the direct-current electric energy transmission of the high-power switch tube module, an internal auxiliary source module, a signal control module, an isolation driving module, an isolation auxiliary source module and an auxiliary source monitoring module which are connected in sequence; the internal auxiliary source module is connected with an external low-voltage power supply, and converts the electric energy of the external low-voltage power supply into low-voltage direct-current electric signals with different levels to supply power to the control module; the signal control module is used for generating a PWM driving signal; the isolation driving module is used for isolating the signal control module, isolating and amplifying the PWM driving signal and then driving the high-power switching tube module; the isolation auxiliary source module is connected with the external low-voltage power supply and converts the electric energy of the external low-voltage power supply into direct current to supply power to the isolation driving module; and the auxiliary source monitoring module collects power supply signals of the output end of the external low-voltage power supply G and the output end of the internal auxiliary source module C, and controls the signal control module to continuously output the PWM driving signal or not according to the level change of the power supply signals.

The auxiliary source monitoring module is powered by an isolation auxiliary source module, the isolation auxiliary source module comprises an isolation transformer, an isolation power supply input winding L1 of the isolation transformer is connected with an external low-voltage power supply, the isolation transformer is provided with a driving module power supply winding L2 and a monitoring module power supply winding L3, the driving module power supply winding L2 supplies power to the isolation driving module through a rectifying module and an A output end, and the monitoring module power supply winding L3 supplies power to the auxiliary source monitoring module through the rectifying module and a B output end.

The auxiliary source monitoring module collects a power supply signal at the output end of the isolation auxiliary source module B and power supply signals at the output end of the external low-voltage power supply G and the output end of the internal auxiliary source module C, and controls whether the signal control module continues to output PWM driving signals or not according to the level change of the power supply signals.

The power supply signal is a voltage signal, the voltage acquisition device arranged at the output end of the isolation auxiliary source module B is used for acquiring voltage at a point B, the voltage acquisition device arranged at the output end of the external low-voltage power supply G is used for acquiring voltage at a point G, and the voltage acquisition device arranged at the output end of the internal auxiliary source module C is used for acquiring voltage at a point C.

The auxiliary source monitoring module is internally provided with an input voltage protection threshold, an isolation auxiliary source module voltage protection threshold and an internal auxiliary source module voltage protection threshold, and when the voltage of a point G is lower than the input voltage protection threshold, or the voltage of a point B is lower than the isolation auxiliary source module voltage protection threshold, or the voltage of a point C is lower than the internal auxiliary source module voltage protection threshold, the auxiliary source monitoring module controls the signal control module to stop outputting the PWM driving signal.

The high-power switch tube module adopts a three-phase full-bridge topological structure comprising 6 switch tubes to form 3 bridge arms.

The external low-voltage power supply is low-voltage direct current, and the internal auxiliary source module is a DCDC module.

The external low-voltage power supply is low-voltage alternating current, and the internal auxiliary source module adopts an ACDC module.

The high-power switch tube modules and the isolation driving modules are provided with a plurality of same numbers, and one isolation driving module correspondingly drives one high-power switch tube module; the auxiliary source monitoring module is powered by an isolation auxiliary source module, the isolation auxiliary source module comprises an isolation transformer, an isolation power supply input winding L1 of the isolation transformer is connected with an external low-voltage power supply, the isolation transformer is provided with a monitoring module power supply winding L3 and a plurality of driving module power supply windings (L21 … … L2 n), the driving module power supply windings supply power to corresponding isolation driving modules through respective rectifying modules and output ends, and the monitoring module power supply winding L3 supplies power to the auxiliary source monitoring module through the rectifying modules and the B output end.

The auxiliary source monitoring module is powered by an isolation auxiliary source module, the isolation auxiliary source module comprises an isolation transformer, an isolation power supply input winding L1 of the isolation transformer is connected with an external low-voltage power supply, the isolation transformer is provided with a driving module power supply winding L2 and at least two monitoring module power supply windings (L31 … … L3 n), the driving module power supply winding L2 supplies power to the isolation driving module through a rectifying module and an A output end, and the monitoring module power supply windings supply power to the auxiliary source monitoring module through respective rectifying modules and output ends.

The utility model also designs an on-vehicle charger, on-vehicle charger adopts foretell auxiliary source monitoring circuit. The high-voltage battery is a vehicle-mounted high-voltage battery.

The utility model provides a technical scheme's beneficial effect is:

the utility model provides a monitoring system of an auxiliary power supply aiming at the auxiliary source driving power supply monitoring demand of the high-power switch tube of the vehicle-mounted charger, which can monitor the internal auxiliary source module and the isolation auxiliary source module of the high-power switch tube of the vehicle-mounted charger, and can cut off the control signal of the high-power switch tube in time when the external power supply of the vehicle-mounted charger is abnormal, thereby avoiding the failure of the vehicle-mounted charger; in addition, when a single high-power switching tube fails, the auxiliary source monitoring module can timely protect the vehicle-mounted charger or the internal control module from supplying power, so that more devices fail when the driving power supply is abnormal, or other parts of the whole vehicle fail.

Drawings

The invention is explained in more detail below with reference to exemplary embodiments and the accompanying drawings, in which:

FIG. 1 is a schematic block diagram of a preferred embodiment of the present invention;

fig. 2 is a schematic diagram of an isolation transformer according to a preferred embodiment of the present invention;

FIG. 3 is a timing diagram of the operation of the unmounted auxiliary source monitoring circuit under a power failure condition;

FIG. 4 is a timing diagram of the operation of the installed auxiliary source monitoring circuit under a power failure condition;

FIG. 5 is a circuit for monitoring a plurality of auxiliary sources of a high power switching tube module;

FIG. 6 is a schematic diagram of an isolation transformer in an embodiment of a plurality of high power switching tube modules;

FIG. 7 is a monitoring circuit having a plurality of monitoring module power windings;

fig. 8 is a schematic diagram of an isolation transformer with multiple monitoring module supply windings.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more clearly understood, the present invention will be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The utility model discloses an auxiliary source monitoring circuit, which is shown in figure 1 and comprises a high-power switch tube module connected with an external high-voltage power supply, a high-voltage battery receiving the direct-current electric energy transmission of the high-power switch tube module, an internal auxiliary source module, a signal control module, an isolation driving module, an isolation auxiliary source module and an auxiliary source monitoring module which are connected in sequence; the internal auxiliary source module is connected with an external low-voltage power supply, and converts the electric energy of the external low-voltage power supply into low-voltage direct-current electric signals with different levels to supply power to the control module; the signal control module is used for generating a PWM driving signal; the isolation driving module is used for isolating the signal control module, isolating and amplifying the PWM driving signal and then driving the high-power switching tube module; the isolation auxiliary source module is connected with the external low-voltage power supply and converts the electric energy of the external low-voltage power supply into direct current to supply power to the isolation driving module; and the auxiliary source monitoring module collects power supply signals of the output end of the external low-voltage power supply G and the output end of the internal auxiliary source module C, and controls the signal control module to continuously output the PWM driving signal or not according to the level change of the power supply signals.

Referring to fig. 1, the embodiment of the present invention in an electric vehicle, Q1, Q2, Q3, Q4, Q5, Q6 are high power switching tubes of a vehicle-mounted charger, and the main function is to convert the ac input of the high voltage external power supply into dc power for storing energy in the storage battery of the electric vehicle. The driving circuit F is a PWM driving signal output by the isolation driving module and mainly has the function of driving the high-power switching tube to work. The driving circuit E is an output driving signal of the signal control module, an input signal of the isolation driving module and has the main function of providing the driving signal for the isolation driving module to perform signal conversion. The high-power switching tube is used as a main module of the vehicle-mounted charger and is used for converting external high-voltage alternating current input power supply into high-voltage direct current to store energy for a battery on the electric vehicle. The control of the high-power switch tube is controlled by the signal control module according to the sampling information, the drive of the high-power switch tube belongs to the signal of a high-voltage system, and the signal control module belongs to a low-voltage system, so that the drive module needs to be isolated to convert PWM (pulse-width modulation) drive signals. Therefore, the power supply of the isolation driving module and the signal control module needs independent auxiliary source modules.

The auxiliary source monitoring module is powered by an isolated auxiliary source module, referring to the schematic diagram of an isolation transformer in the preferred embodiment shown in fig. 2, the isolated auxiliary source module includes an isolation transformer, an isolated power input winding L1 of the isolation transformer is connected to an external low voltage power supply, the isolation transformer has a driving module power supply winding L2 and a monitoring module power supply winding L3, the driving module power supply winding L2 supplies power to the isolated driving module through a rectifying module and an a output terminal, and the monitoring module power supply winding L3 supplies power to the auxiliary source monitoring module through the rectifying module and a B output terminal. And the pressure resistance design requirements are met between every two of L1, L2 and L3. The monitoring of the L2 winding voltage abnormity can be realized by monitoring the L3 winding voltage, the auxiliary source voltage monitoring mode has cost advantage compared with the direct voltage monitoring mode, and meanwhile, the isolation design of auxiliary source monitoring is realized.

In a preferred embodiment, the power supply signal is a voltage signal, the voltage collecting device disposed at the output end of the isolation auxiliary source module B is used for collecting a voltage at a point B, the voltage collecting device disposed at the output end of the external low-voltage power supply G is used for collecting a voltage at a point G, and the voltage collecting device disposed at the output end of the internal auxiliary source module C is used for collecting a voltage at a point C.

In a preferred embodiment, the auxiliary source monitoring module is internally provided with an input voltage protection threshold, an isolated auxiliary source module voltage protection threshold and an internal auxiliary source module voltage protection threshold, and when a voltage at a point G is lower than the input voltage protection threshold, or a voltage at a point B is lower than the isolated auxiliary source module voltage protection threshold, or a voltage at a point C is lower than the internal auxiliary source module voltage protection threshold, the auxiliary source monitoring module controls the signal control module to stop outputting the PWM driving signal. In practical applications, after the auxiliary source monitoring module monitors that the charger fails, the auxiliary source monitoring module sends a signal to the signal control module through a protection flag signal (signal D in fig. 1), and the signal control module stops outputting the PWM driving signal.

Referring to the preferred embodiment shown in fig. 1, the high power switching tube module includes, but is not limited to, a three-phase full bridge topology, a single-phase topology, an electrically driven three-phase drive system, and the like high power bridge topology. The external low-voltage power supply is low-voltage direct current, and the internal auxiliary source module is a DCDC module. The external low-voltage power supply is low-voltage alternating current, and the internal auxiliary source module adopts an ACDC module.

The working principle of the present invention will be further explained with reference to fig. 1 and 2.

The utility model discloses inside auxiliary source module C output C point voltage carries out direct monitoring, when C point voltage takes place unusually, this trouble is discerned to auxiliary source monitoring module to through auxiliary source fault signal D, give signal control module with this trouble information transfer. The signal control module cuts off an output control signal E to realize the turn-off control of the high-power switching tube module, and the vehicle-mounted charger and the whole vehicle are ensured to be in a safe state.

The utility model discloses the control to the A point voltage of keeping apart auxiliary source module A output is indirect control, because A point voltage is the power supply of keeping apart drive module, belongs to the high-pressure module, and auxiliary source monitoring module can't directly monitor it and detect. The power supply signal from the external low-voltage auxiliary source can construct the voltage at the point A and the voltage at the point B through the isolation transformer and the rectifier bridge. The voltage at the point B and the voltage at the point A belong to different windings of an isolation auxiliary source, and the voltage at the point A can be indirectly monitored by directly monitoring the voltage at the point B. And once the voltage abnormality of the point B is detected, the signal is transmitted to the signal control module through an auxiliary source fault signal D. Therefore, the signal control module cuts off the control signal before the voltage of the point A falls to the failure level of the power tube, and the protection of the high-power switch tube module is realized. The voltage of the point G is a monitoring signal of an external low-voltage power supply, and the monitoring (including isolated power supply and non-isolated power supply) of a low-voltage power supply module of the whole vehicle-mounted charger can be realized by using G, B, C power supply monitoring signals, so that the whole power module and the low-voltage module are protected.

Fig. 3 is a timing diagram of the action of the monitoring circuit without the auxiliary source under the power supply failure condition, when the power supply signal fails, the signal control module cannot acquire the failure information in time, and still maintains the normal output of the driving control signal. In this state, the supply voltage of the isolation drive control module is gradually reduced, resulting in a gradual reduction of the drive signal level of the high-power switching tube. The high-power switching tube is sensitive to the driving level, and when the driving level is not in the required range, the high-power switching tube is prone to power thermal failure.

Fig. 4 is a timing diagram of the action of the installed auxiliary source monitoring circuit under the condition of power supply failure, when the isolated auxiliary source fails, the auxiliary source monitoring module can detect the power supply failure in time by monitoring the voltage of the point B, trigger a failure signal D, and transmit the failure information to the signal control module, and the signal control module can cut off the input of the control signal for cutting off the power transmission module before the driving level of the high-power switching tube is reduced to the failure level, so that the protection of the high-power switching tube is realized, and the damage of the charger of the whole vehicle to a larger area is avoided.

The utility model provides an auxiliary source monitoring circuit can realize the low voltage system and to the control protection of the isolation power supply of high voltage system, can be used for including but not limited to on-vehicle charger, on-vehicle direct current converter, the electric application scenes such as control system that drives. Referring to fig. 5, a circuit for monitoring a plurality of auxiliary sources of the high-power switching tube module is shown, wherein the high-power switching tube module (1-n) and the isolation driving module (1-n) are provided with a plurality of modules and the number of the modules is the same, one isolation driving module correspondingly drives one high-power switching tube module, and one high-power switching tube module is correspondingly connected with one high-voltage battery; the auxiliary source monitoring module is powered by the isolation auxiliary source module. Referring to fig. 6, a schematic diagram of an isolation transformer in an embodiment of a plurality of high power switching tube modules is shown, the isolation auxiliary source module includes an isolation transformer, an isolation power input winding L1 of the isolation transformer is connected with an external low voltage power supply, the isolation transformer has a monitoring module power supply winding L3 and a plurality of driving module power supply windings (L21 … … L2 n), the driving module power supply windings supply power to corresponding isolation driving modules through respective rectifying modules and output terminals, and the monitoring module power supply winding L3 supplies power to the auxiliary source monitoring module through the rectifying modules and the B output terminal. Referring to fig. 5 and 6, the driving module power supply winding L21 corresponds to the isolated driving module 1, and the driving module power supply winding L2n corresponds to the isolated driving module n.

Fig. 7 shows a monitoring circuit with a plurality of monitoring module supply windings, the auxiliary source monitoring module being supplied by an isolated auxiliary source module, see fig. 8 for a schematic of an isolation transformer with a plurality of monitoring module supply windings, the isolated auxiliary source module comprising an isolation transformer having an isolated supply input winding L1 connected to an external low voltage supply, the isolation transformer having a drive module supply winding L2 and at least two monitoring module supply windings (L31 … … L3 n), the drive module supply winding L2 supplying power to the isolated drive module through a rectifier module and an a output, the monitoring module supply windings supplying power to the auxiliary source monitoring module through respective rectifier module and output. With reference to fig. 7 and 8, at least two windings, L31 and L3n, are used to supply power to the monitoring modules, which is due to the requirement of dual backup of the detection line and the winding, so as to avoid inaccurate detection caused by disconnection of the power supply winding or the line of one monitoring module.

The utility model also discloses a vehicle-mounted charger, vehicle-mounted charger adopts foretell auxiliary source monitoring circuit.

In a preferred embodiment, the high-voltage battery is a vehicle-mounted high-voltage battery, and the power supply is single-phase or three-phase mains supply.

The foregoing examples are illustrative only and are not intended to be limiting. Any equivalent modifications or variations without departing from the spirit and scope of the present application should be included in the claims of the present application.

Claims

1. The utility model provides an auxiliary source monitoring circuit, is including the high-power switch tube module of connecting outside high voltage power supply, the high-voltage battery who accepts high-power switch tube module direct current power transmission which characterized in that: the system also comprises an internal auxiliary source module, a signal control module, an isolation driving module, an isolation auxiliary source module and an auxiliary source monitoring module which are sequentially connected;

the internal auxiliary source module is connected with an external low-voltage power supply, and converts the electric energy of the external low-voltage power supply into low-voltage direct-current electric signals with different levels to supply power to the control module;

the signal control module is used for generating a PWM driving signal;

the isolation driving module is used for isolating the signal control module, isolating and amplifying the PWM driving signal and then driving the high-power switching tube module;

the isolation auxiliary source module is connected with the external low-voltage power supply and converts the electric energy of the external low-voltage power supply into direct current to supply power to the isolation driving module;

and the auxiliary source monitoring module collects power supply signals of the output end of the external low-voltage power supply G and the output end of the internal auxiliary source module C, and controls the signal control module to continuously output the PWM driving signal or not according to the level change of the power supply signals.

2. The auxiliary source monitoring circuit of claim 1, wherein: the auxiliary source monitoring module is powered by an isolation auxiliary source module, the isolation auxiliary source module comprises an isolation transformer, an isolation power supply input winding L1 of the isolation transformer is connected with an external low-voltage power supply, the isolation transformer is provided with a driving module power supply winding L2 and a monitoring module power supply winding L3, the driving module power supply winding L2 supplies power to the isolation driving module through a rectifying module and an A output end, and the monitoring module power supply winding L3 supplies power to the auxiliary source monitoring module through the rectifying module and a B output end.

3. The auxiliary source monitoring circuit of claim 2, wherein: the auxiliary source monitoring module collects a power supply signal at the output end of the isolation auxiliary source module B and power supply signals at the output end of the external low-voltage power supply G and the output end of the internal auxiliary source module C, and controls whether the signal control module continues to output PWM driving signals or not according to the level change of the power supply signals.

4. The auxiliary source monitoring circuit of claim 3, wherein: the power supply signal is a voltage signal, the voltage acquisition device arranged at the output end of the isolation auxiliary source module B is used for acquiring voltage at a point B, the voltage acquisition device arranged at the output end of the external low-voltage power supply G is used for acquiring voltage at a point G, and the voltage acquisition device arranged at the output end of the internal auxiliary source module C is used for acquiring voltage at a point C.

5. The auxiliary source monitoring circuit of claim 4, wherein: the auxiliary source monitoring module is internally provided with an input voltage protection threshold, an isolation auxiliary source module voltage protection threshold and an internal auxiliary source module voltage protection threshold, and when the voltage of a point G is lower than the input voltage protection threshold, or the voltage of a point B is lower than the isolation auxiliary source module voltage protection threshold, or the voltage of a point C is lower than the internal auxiliary source module voltage protection threshold, the auxiliary source monitoring module controls the signal control module to stop outputting the PWM driving signal.

6. The auxiliary source monitoring circuit of claim 1, wherein: the high-power switch tube module adopts a three-phase full-bridge topological structure comprising 6 switch tubes to form 3 bridge arms.

7. The auxiliary source monitoring circuit of claim 1, wherein: the external low-voltage power supply is low-voltage direct current, and the internal auxiliary source module is a DCDC module.

8. The auxiliary source monitoring circuit of claim 1, wherein: the external low-voltage power supply is low-voltage alternating current, and the internal auxiliary source module adopts an ACDC module.

9. The auxiliary source monitoring circuit of claim 1, wherein: the high-power switch tube modules and the isolation driving modules are provided with a plurality of same numbers, and one isolation driving module correspondingly drives one high-power switch tube module; the auxiliary source monitoring module is powered by an isolation auxiliary source module, the isolation auxiliary source module comprises an isolation transformer, an isolation power supply input winding L1 of the isolation transformer is connected with an external low-voltage power supply, the isolation transformer is provided with a monitoring module power supply winding L3 and a plurality of driving module power supply windings, the driving module power supply windings supply power to corresponding isolation driving modules through respective rectifying modules and output ends, and the monitoring module power supply winding L3 supplies power to the auxiliary source monitoring module through the rectifying modules and the output end B.

10. The auxiliary source monitoring circuit of claim 1, wherein: the auxiliary source monitoring module is powered by an isolation auxiliary source module, the isolation auxiliary source module comprises an isolation transformer, an isolation power supply input winding L1 of the isolation transformer is connected with an external low-voltage power supply, the isolation transformer is provided with a driving module power supply winding L2 and at least two monitoring module power supply windings, the driving module power supply winding L2 supplies power to the isolation driving module through a rectifying module and an A output end, and the monitoring module power supply windings supply power to the auxiliary source monitoring module through respective rectifying modules and output ends.

11. An on-vehicle charger, characterized by: the vehicle-mounted charger adopts the auxiliary source monitoring circuit of any one of claims 1 to 10.

12. The vehicle-mounted charger according to claim 11, characterized in that: the high-voltage battery is a vehicle-mounted high-voltage battery.