HK40000493B - Hybrid vehicle and power system thereof - Google Patents

Description

Hybrid electric vehicles and their power systems

Technical Field

The present invention relates to the technical field of hybrid electric vehicles, and in particular to a power system of a hybrid electric vehicle and a hybrid electric vehicle.

Background Art

In hybrid vehicles, the voltage generated by the motor is rectified by the inverter and used to charge the power battery. While the voltage at the inverter's output is uncontrolled, the battery acts as a large capacitive load because the output is connected in parallel with the power battery, stabilizing the voltage in the main circuit and minimizing the impact on the subsequent DC-DC converter. Furthermore, the high voltage can be directly stepped down by the DC-DC converter to a low voltage, such as 12V, to power the vehicle's low-voltage electrical appliances.

However, once the power battery is disconnected, the motor's output voltage becomes uncontrollable. Therefore, the motor's output voltage must be stabilized before it can be used by subsequent loads. Due to significant voltage fluctuations at the inverter end, the amplitude and frequency of the motor's back EMF output vary with load (i.e., engine speed). For example, at high speeds, the back EMF is very high, and the rectifier-regulated output voltage is often very high. If a brake rectifier is used, the output voltage will become uncontrollable once the power battery is disconnected. If uncontrolled rectification is used, losses will be significant.

Summary of the Invention

The present invention aims to solve one of the technical problems in the above-mentioned technology at least to a certain extent.

Therefore, an object of the present invention is to provide a power system for a hybrid electric vehicle, wherein the power system can keep the input voltage of a DC-DC converter stable and ensure the normal operation of the DC-DC converter.

Another object of the present invention is to provide a hybrid vehicle.

To achieve the above-mentioned objectives, the first embodiment of the present invention proposes a power system for a hybrid vehicle, comprising: an engine, the engine outputting power to the wheels of the hybrid vehicle through a clutch; a power motor, the power motor being used to output driving force to the wheels of the hybrid vehicle, the power motor including a power motor controller, the power motor controller including a first regulator; a power battery, the power battery being used to power the power motor; a DC-DC converter; an auxiliary motor connected to the engine, the auxiliary motor being respectively connected to the power motor, the DC-DC converter and the power battery, the auxiliary motor including Auxiliary motor controller, the auxiliary motor controller includes an inverter and a second regulator; a voltage stabilizing circuit, the voltage stabilizing circuit is connected between the auxiliary motor and the DC-DC converter, and the voltage stabilizing circuit stabilizes the direct current output to the DC-DC converter when the auxiliary motor generates electricity; wherein, the second regulator is used to control the voltage stabilizing circuit to perform voltage stabilization when the power battery is disconnected from the DC-DC converter and the auxiliary motor controller is valid, and the first regulator is used to control the voltage stabilizing circuit to perform voltage stabilization when the power battery is disconnected from the DC-DC converter and the auxiliary motor controller fails.

According to the power system of the hybrid vehicle proposed in an embodiment of the present invention, the engine outputs power to the wheels of the hybrid vehicle through the clutch, the power motor outputs driving force to the wheels of the hybrid vehicle, the power battery supplies power to the power motor, and the voltage stabilizing circuit stabilizes the direct current output to the DC-DC converter when the auxiliary motor generates electricity. In addition, the second regulator controls the voltage stabilizing circuit to perform voltage stabilization when the power battery is disconnected from the DC-DC converter and the auxiliary motor controller is valid. The first regulator controls the voltage stabilizing circuit to perform voltage stabilization when the power battery is disconnected from the DC-DC converter and the auxiliary motor controller fails. This not only maintains the low-speed electrical balance and low-speed smoothness of the entire vehicle and improves the performance of the entire vehicle, but also keeps the input voltage of the DC-DC converter stable in the event of power battery failure or failure of both the power battery and the auxiliary motor controller, thereby ensuring the normal operation of the DC-DC converter and the normal driving of the entire vehicle.

Furthermore, the present invention provides a hybrid vehicle, which includes the power system of the hybrid vehicle described above.

The hybrid vehicle proposed in accordance with an embodiment of the present invention, through the power system of the hybrid vehicle, can not only maintain the low-speed electrical balance and low-speed smoothness of the entire vehicle, thereby improving the performance of the entire vehicle, but can also keep the input voltage of the DC-DC converter stable in the event of failure of the power battery or failure of both the power battery and the auxiliary motor controller, thereby ensuring the normal operation of the DC-DC converter and the normal driving of the entire vehicle.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and/or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments with reference to the accompanying drawings, in which:

FIG1 is a structural block diagram of a power system of a hybrid vehicle according to one embodiment of the present invention;

FIG2 a is a schematic structural diagram of a power system of a hybrid vehicle according to an embodiment of the present invention;

FIG2 b is a schematic structural diagram of a power system of a hybrid vehicle according to another embodiment of the present invention;

FIG2 c is a schematic structural diagram of a power system of a hybrid vehicle according to another embodiment of the present invention;

FIG3 a is a structural block diagram of a voltage stabilizing circuit according to an embodiment of the present invention;

FIG3 b is a structural block diagram of a voltage stabilizing circuit according to another embodiment of the present invention.

FIG4 is a schematic diagram of voltage stabilization control according to an embodiment of the present invention;

FIG5 is a structural block diagram of a power system of a hybrid vehicle according to a specific embodiment of the present invention; and

FIG6 is a structural block diagram of a hybrid vehicle according to an embodiment of the present invention.

DETAILED DESCRIPTION

The following describes embodiments of the present invention in detail, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and are not to be construed as limiting the present invention.

The following describes a power system of a hybrid vehicle and a hybrid vehicle according to embodiments of the present invention with reference to the accompanying drawings.

Figure 1 is a block diagram of a hybrid vehicle power system according to an embodiment of the present invention. As shown in Figure 1 , the hybrid vehicle power system 100 includes an engine 1 , a power motor 2 , a power battery 3 , a DC-DC converter 4 , an auxiliary motor 5 , and a voltage stabilization circuit 6 .

As shown in Figures 1-3 , the engine 1 outputs power to the hybrid vehicle's wheels 8 via a clutch 7; the power motor 2 is used to output driving force to the hybrid vehicle's wheels 8. In other words, the power system of the embodiments of the present invention can provide power for the hybrid vehicle's normal driving via the engine 1 and/or the power motor 2. In other words, in some embodiments of the present invention, the power source of the power system can be the engine 1 and the power motor 2, either of which can independently output power to the wheels 8, or both can simultaneously output power to the wheels 8.

The power battery 3 is used to power the power motor 2. The auxiliary motor 5 is connected to the engine 1, for example, through the gear train terminal of the engine 1. The auxiliary motor 5 is connected to the power motor 2, the DC-DC converter 4, and the power battery 3. A voltage stabilization circuit 6 is connected between the auxiliary motor 5 and the DC-DC converter 4. This circuit stabilizes the DC power output by the auxiliary motor 5 to the DC-DC converter 4 during power generation, so that the stabilized voltage is supplied to the vehicle's low-voltage electrical equipment through the DC-DC converter 4. In other words, the power output of the auxiliary motor 5 during power generation passes through the voltage stabilization circuit 6, and then outputs a stabilized voltage that is supplied to the DC-DC converter 4.

As a result, the power motor 2 and auxiliary motor 5 can function as the drive motor and generator, respectively. This allows the auxiliary motor 5 to generate high power and efficiency at low speeds, thereby meeting the power requirements of low-speed driving, maintaining the vehicle's electrical balance and smoothness at low speeds, and improving overall vehicle performance. Furthermore, the voltage stabilizing circuit 6 can stabilize the DC power output from the auxiliary motor 5 to the DC-DC converter 4 during power generation, maintaining a stable input voltage to the DC-DC converter 4 and ensuring proper operation of the DC-DC converter.

Furthermore, when the auxiliary motor 5 generates electricity driven by the engine 1, it can at least one of charge the power battery 3, power the power motor 2, and power the DC-DC converter 4. In other words, the engine 1 can drive the auxiliary motor 5 to generate electricity, and the electricity generated by the auxiliary motor 5 can be provided to at least one of the power battery 3, the power motor 2, and the DC-DC converter 4. It should be understood that the engine 1 can drive the auxiliary motor 5 to generate electricity while outputting power to the wheels 8, or it can drive the auxiliary motor 5 alone to generate electricity.

The auxiliary motor 5 can be a BSG motor. It should be noted that the auxiliary motor 5 is a high-voltage motor. For example, the voltage generated by the auxiliary motor 5 is comparable to the voltage of the power battery 3. Therefore, the electricity generated by the auxiliary motor 5 can directly charge the power battery 3 without voltage conversion, and can also power the power motor 2 and/or the DC-DC converter 4. Furthermore, the auxiliary motor 5 can also be a high-efficiency generator. For example, when the engine 1 is idling and driving the auxiliary motor 5 to generate electricity, a power generation efficiency of over 97% can be achieved.

It should be noted that the voltage stabilizing circuit 6 can be provided on the output line of the auxiliary motor 5, and the auxiliary motor 5 is connected to the power motor 2, the power battery 3, and the DC-DC converter 4 respectively through the voltage stabilizing circuit 6, as shown in Figures 2b and 2c. In this case, when the auxiliary motor 5 generates electricity, it can output a stable voltage through the voltage stabilizing circuit 6, thereby achieving stable charging of the power battery 3, stable power supply to the power motor 2, and stable power supply to the DC-DC converter 4. Therefore, regardless of whether the power battery 3 and the DC-DC converter 4 are connected or not, the normal operation of the DC-DC converter 4 can be guaranteed. The voltage stabilizing circuit 6 can also be provided on the input line of the DC-DC converter 4, and the auxiliary motor 5 can be connected to the DC-DC converter 4 and the power battery 3 respectively, and the power battery 3 can be connected to the DC-DC converter 4 at the same time, as shown in Figures 1 and 2a. Therefore, when the power battery 3 is disconnected from the DC-DC converter 4, the voltage output by the auxiliary motor 5 to the DC-DC converter 4 when generating electricity remains stable, thereby ensuring the normal operation of the DC-DC converter 4.

Furthermore, the auxiliary motor 5 can be used to start the engine 1, that is, the auxiliary motor 5 can realize the function of starting the engine 1. For example, when starting the engine 1, the auxiliary motor 5 can drive the crankshaft of the engine 1 to rotate so that the piston of the engine 1 reaches the ignition position, thereby realizing the starting of the engine 1. Therefore, the auxiliary motor 5 can realize the function of the starter in the related technology.

As described above, both the engine 1 and the power motor 2 can be used to drive the wheels 8 of the hybrid vehicle. For example, as shown in Figures 2a and 2b, the engine 1 and the power motor 2 jointly drive the same wheel of the hybrid vehicle, such as a pair of front wheels 81 (including the left front wheel and the right front wheel). For another example, as shown in Figure 2c, the engine 1 can drive a first wheel of the hybrid vehicle, such as the pair of front wheels 81 (including the left front wheel and the right front wheel), and the power motor 2 can drive a second wheel of the hybrid vehicle, such as a pair of rear wheels 82 (including the left rear wheel and the right rear wheel).

In other words, when the engine 1 and the power motor 2 jointly drive a pair of front wheels 81, the driving force of the power system will be output to the pair of front wheels 81, and the whole vehicle adopts a two-wheel drive mode; when the engine 1 drives a pair of front wheels 81 and the power motor 2 drives a pair of rear wheels 82, the driving force of the power system will be output to the pair of front wheels 81 and the pair of rear wheels 82 respectively, and the whole vehicle adopts a four-wheel drive mode.

Furthermore, in the two-wheel drive mode, as shown in Figures 2a and 2b, the power system 100 of the hybrid vehicle also includes a final reducer 9 and a first transmission 91, wherein the engine 1 outputs power to the first wheel of the hybrid vehicle, such as a pair of front wheels 81, through the clutch 7, the first transmission 91, and the final reducer 9, and the power motor 2 outputs driving force to the first wheel of the hybrid vehicle, such as a pair of front wheels 81, through the final reducer 9.

In the four-wheel drive mode, as shown in Figure 2c, the power system 100 of the hybrid vehicle also includes a first transmission 91 and a second transmission 92, wherein the engine 1 outputs power to the first wheel of the hybrid vehicle, such as a pair of front wheels 81, through the clutch 7 and the first transmission 91, and the power motor 2 outputs driving force to the second wheel of the hybrid vehicle, such as a pair of rear wheels 82, through the second transmission 92.

The clutch 7 and the first transmission 91 can be integrated.

In the embodiment of the present invention, since the generated voltage of the auxiliary motor 5 is supplied to both ends of the power battery 3, the voltage input to the DC-DC converter 4 is stable when the power battery 3 is connected to the DC-DC converter 4. If the power battery 3 fails or is damaged and disconnected from the DC-DC converter 4, it is necessary to control the power output of the auxiliary motor 5 during power generation. Specifically, the voltage stabilizing circuit 6 is used to stabilize the DC power output to the DC-DC converter 4 during power generation.

In some embodiments of the present invention, as shown in FIG1 , the power motor 2 includes a power motor controller 21 , which includes a first regulator 211 ; the auxiliary motor 5 includes an auxiliary motor controller 51 , which includes an inverter 511 and a second regulator 512 .

Among them, the second regulator 512 is used to control the voltage stabilization circuit 6 to perform voltage stabilization when the power battery 3 is disconnected from the DC-DC converter 4 and the auxiliary motor controller 51 is valid, and the first regulator 211 is used to control the voltage stabilization circuit 6 to perform voltage stabilization when the power battery 3 is disconnected from the DC-DC converter 4 and the auxiliary motor controller 51 fails.

It should be noted that the failure of the auxiliary motor controller 51 may mean that the auxiliary motor controller 51 is unable to perform voltage stabilization processing, and conversely, the validity of the auxiliary motor controller 51 may mean that the auxiliary motor controller 51 is able to perform voltage stabilization processing.

That is to say, when the power battery 3 is disconnected, the entire vehicle still needs to run normally, and the auxiliary motor controller 51 performs voltage stabilization. If the auxiliary motor controller 51 fails, the power motor controller will be responsible for voltage stabilization. Therefore, when the power battery 3 and the auxiliary motor controller 51 fail at the same time, the entire vehicle can still run normally and can also avoid consuming the battery power.

Specifically, the voltage stabilization process of the embodiment of the present invention is described in a series-parallel mode and a series mode respectively.

During normal vehicle operation, when the hybrid vehicle is operating in parallel-parallel mode, if the main contactor of the battery management system (BMS) of power battery 3 is disconnected, it indicates that power battery 3 is disconnected, and further determination is made as to whether auxiliary motor controller 51 has failed. If auxiliary motor controller 51 has failed, auxiliary motor controller 51 stops voltage stabilization, and power motor controller 21 performs voltage stabilization. If auxiliary motor controller 51 has failed, power motor controller 21 stops voltage stabilization, and auxiliary motor controller 51 performs voltage stabilization.

During normal vehicle operation, when the hybrid vehicle is operating in series mode, if the main contactor of the battery management system (BMS) of power battery 3 is disconnected, it indicates that power battery 3 is disconnected, and further determination is made as to whether auxiliary motor controller 51 has failed. If auxiliary motor controller 51 has failed, auxiliary motor controller 51 stops voltage stabilization, and power motor controller 21 performs voltage stabilization. If auxiliary motor controller 51 has failed, power motor controller 21 stops voltage stabilization, and auxiliary motor controller 51 performs voltage stabilization.

In addition, in some embodiments of the present invention, the hybrid vehicle's vehicle controller can determine whether the power battery 3 is disconnected and whether the auxiliary motor controller 51 has failed. For example, the vehicle controller can communicate with the power battery 3 via the CAN bus to determine whether the power battery 3 is disconnected. The vehicle controller can also communicate with the auxiliary motor controller 51 via the CAN bus to determine whether the auxiliary motor controller 51 has failed. If the power battery 3 is disconnected and the auxiliary motor controller 51 is valid, the vehicle controller can send a voltage stabilization instruction to the auxiliary motor controller 51. If the power battery 3 is disconnected and the auxiliary motor controller 51 is valid, the vehicle controller can communicate with the power motor controller 21 via the CAN bus to send a voltage stabilization instruction to the power motor controller 21. Alternatively, in some other embodiments, communication between the power battery 3, the auxiliary motor controller 51, and the power motor controller 21 can determine whether the power battery 3 is disconnected and whether the auxiliary motor controller 51 has failed. The auxiliary motor controller 51 can communicate with the power battery 3 to determine whether the power battery 3 is disconnected. If the power battery 3 is disconnected and the auxiliary motor controller 51 is valid, the auxiliary motor controller 51 can perform voltage stabilization. If the auxiliary motor controller 51 itself is invalid, the auxiliary motor controller 51 can also send a voltage stabilization instruction to the power motor controller 21.

Specifically, according to one embodiment of the present invention, the first regulator 211 and the second regulator 512 are both used to output a first adjustment signal and a second adjustment signal according to the output signal of the voltage stabilizing circuit 6, so that the DC bus voltage output by the inverter 511 remains stable, wherein the first adjustment signal is used to adjust the d-axis current of the auxiliary motor 5, and the second adjustment signal is used to adjust the q-axis current of the auxiliary motor 5.

That is to say, when the first regulator 211 controls the voltage stabilizing circuit 6 to perform voltage stabilization processing, the first regulator 211 outputs the first regulation signal and the second regulation signal according to the output signal of the voltage stabilizing circuit 6; when the second regulator 512 controls the voltage stabilizing circuit 6 to perform voltage stabilization processing, the second regulator 512 outputs the first regulation signal and the second regulation signal according to the output signal of the voltage stabilizing circuit 6.

Furthermore, in some embodiments, as shown in Figures 3a and 3b, the voltage stabilization circuit 6 includes a first voltage sampler 61 and a target voltage collector 62. The first voltage sampler 61 samples the DC bus voltage output by the inverter 511 to obtain a first voltage sampling value, and outputs the first voltage sampling value to the first regulator 211 or the second regulator 512. The target voltage collector 62 obtains a target reference voltage and sends the target reference voltage to the first regulator 211 or the second regulator 512. The first regulator 211 and the second regulator 512 are both configured to output a first regulation signal and a second regulation signal based on the voltage difference between the target reference voltage and the first voltage sampling value. The output signal of the voltage stabilization circuit 6 includes the first voltage sampling value and the target reference voltage.

Specifically, the auxiliary motor controller 51 is connected to the DC-DC converter 4 through the voltage stabilizing circuit 6 , and the auxiliary motor controller 51 outputs a DC bus voltage through the inverter 511 .

When the second regulator 512 controls the voltage stabilization circuit 6 to perform voltage stabilization, as shown in FIG3 a , the first voltage sampler 61 samples the DC bus voltage output by the inverter 511 to obtain a first voltage sampling value, and outputs the first voltage sampling value to the second regulator 512. The target voltage collector 62 obtains a target reference voltage and sends the target reference voltage to the second regulator 512. The second regulator 512 outputs a first regulation signal and a second regulation signal based on the voltage difference between the target reference voltage and the first voltage sampling value. The first regulation signal is used to regulate the d-axis current of the auxiliary motor 5, and the second regulation signal is used to regulate the q-axis current of the auxiliary motor 5. When the power battery 3 is disconnected from the DC-DC converter 4, the auxiliary motor controller 51 controls the inverter 511 based on the d-axis current and the q-axis current of the auxiliary motor 5, so that the DC bus voltage output by the inverter 511 remains stable.

When the first regulator 211 controls the voltage stabilization circuit 6 to perform voltage stabilization, as shown in FIG3b , the first voltage sampler 61 samples the DC bus voltage output by the inverter 511 to obtain a first voltage sampling value, and outputs the first voltage sampling value to the first regulator 211. The target voltage collector 62 obtains a target reference voltage and sends the target reference voltage to the first regulator 211. The first regulator 211 outputs a first regulation signal and a second regulation signal based on the voltage difference between the target reference voltage and the first voltage sampling value. The first regulation signal is used to regulate the d-axis current of the auxiliary motor 5, and the second regulation signal is used to regulate the q-axis current of the auxiliary motor 5. This allows the power motor controller 21 to control the inverter 511 based on the d-axis current and q-axis current of the auxiliary motor 5 when the power battery 3 is disconnected from the DC-DC converter 4 and the auxiliary motor controller 51 fails, so that the DC bus voltage output by the inverter 511 remains stable.

In some examples, PWM (Pulse Width Modulation) can be used to control the inverter 511 to maintain a stable DC bus voltage output by the inverter 511. As shown in FIG4 , the first regulator 211 and the second regulator 512 can each include an error calculation unit a, a first PID adjustment unit b, and a second PID adjustment unit c. In other words, the first regulator 211 and the second regulator 512 can have the same structure and control principle.

The error calculation unit a is connected to the first voltage sampler 61 and the target voltage collector 62, respectively, and is used to obtain the voltage difference between the target reference voltage and the first voltage sampling value. The first PID adjustment unit b is connected to the error calculation unit a, and adjusts the voltage difference between the target reference voltage and the first voltage sampling value to output a first adjustment signal. The second PID adjustment unit c is connected to the error calculation unit a, and adjusts the voltage difference between the target reference voltage and the first voltage sampling value to output a second adjustment signal.

Specifically, as shown in FIG4 , the first voltage sampler 61 samples the DC bus voltage output by the inverter 511 in real time to obtain a first voltage sampling value, and outputs the first voltage sampling value to the error calculator a. The target voltage collector 62 obtains a target reference voltage and outputs the target reference voltage to the error calculation unit a. The error calculation unit a obtains the voltage difference between the target reference voltage and the first voltage sampling value, and inputs the difference into the first PID adjustment unit b and the second PID adjustment unit c, respectively. The first PID adjustment unit b outputs a first adjustment signal (i.e., Id ^* in FIG4 ), and the second PID adjustment unit c outputs a second adjustment signal (i.e., Iq ^* in FIG4 ). At this time, the three-phase current output by the auxiliary motor 5 undergoes a 3S/2R transformation, converting it into a d-axis current Id and a q-axis current Iq in the dq coordinate system. The differences between Id ^* and Id, and Iq ^* and Iq, are obtained and controlled by corresponding PID regulators to obtain the α-axis voltage Uα and the β-axis voltage Uβ of the auxiliary motor 5. Uα and Uβ are input to the SVPWM module, which outputs a three-phase duty cycle. This duty cycle is used to control the inverter 511, which adjusts the d-axis current Id and the q-axis current Iq output by the auxiliary motor 5. The adjusted d-axis current of the auxiliary motor is then further adjusted using a first control signal, and the adjusted q-axis current of the auxiliary motor is further adjusted using a second adjustment signal. This forms a closed-loop control of the d-axis and q-axis currents of the auxiliary motor. This closed-loop control ensures that the DC bus voltage output by the inverter 511 remains stable, i.e., the DC voltage output by the auxiliary motor 5 to the DC-DC converter 4 remains stable during power generation.

It should be noted that there is a certain correlation between the DC voltage output by the inverter 511 in the auxiliary motor controller 51 and the back electromotive force output by the auxiliary motor 5. To ensure control efficiency, the voltage output by the inverter 511 can be set to 3/2 of the phase voltage (i.e., the maximum phase voltage in the driving state is 2/3 of the DC bus voltage). As a result, the DC voltage output by the inverter 511 is related to the rotational speed of the auxiliary motor 5. When the rotational speed of the auxiliary motor 5 is higher, the DC voltage output by the inverter 511 is higher, and when the rotational speed of the auxiliary motor 5 is lower, the DC voltage output by the inverter 511 is lower.

Furthermore, in order to ensure that the DC voltage input to the DC-DC converter 4 is within a preset voltage range, in some embodiments of the present invention, as shown in Figures 3a and 3b, the voltage stabilization circuit 6 may also include a voltage stabilizer 63, a second voltage sampler 64 and a voltage stabilization controller 65.

The voltage regulator 63 is connected to the DC output of the inverter 511. The voltage regulator 63 stabilizes the DC bus voltage output by the inverter 511. The output of the voltage regulator 63 is connected to the input of the DC-DC converter 4. The second voltage sampler 64 samples the output voltage of the voltage regulator 63 to obtain a second voltage sampling value. The voltage regulator controller 65 is connected to the voltage regulator 63 and the second voltage sampler 64 respectively. The voltage regulator controller 65 is used to control the output voltage of the voltage regulator 63 based on a preset reference voltage and the second voltage sampling value so that the output voltage of the voltage regulator 63 is within a preset voltage range.

In some examples, voltage regulator 63 can employ a switching voltage regulator circuit, such as a BOOST circuit, which not only boosts voltage but also provides high control precision. The switching device in the BOOST circuit can employ a silicon carbide MOSFET, such as Infineon's IMW120R45M1, which withstands a voltage of 1200V and has an internal resistance of 45mΩ. This device features high voltage resistance, low internal resistance, and excellent thermal conductivity, resulting in losses several dozen times lower than those of a high-speed IGBT of the same specification. The driver chip for voltage regulator 63 can employ Infineon's 1EDI60N12AF, which utilizes coreless transformer isolation for safe and reliable control. It is understood that this driver chip can generate a drive signal.

In other examples, the voltage regulator 63 may adopt a buck-boost circuit, which can reduce the voltage at high speed and increase the voltage at low speed, and has high control accuracy.

In some other examples, the voltage regulator 63 may also adopt a linear voltage regulator circuit or a three-terminal voltage regulator circuit (such as LM317 and 7805, etc.).

It is understood that, to facilitate circuit design, the circuit structures of the first voltage sampler 61 and the second voltage sampler 64 can be identical. For example, the first voltage sampler 61 and the second voltage sampler 64 can both include differential voltage circuits, which have the characteristics of high precision and convenient adjustment of the amplification factor.

Optionally, the voltage regulator controller 65 may use a PWM dedicated modulation chip SG3525, which has the characteristics of small size, simple control, and the ability to output stable PWM waves.

For example, the working process of the power system 100 of the above-mentioned hybrid vehicle is as follows: the second voltage sampler 64 samples the output voltage of the voltage regulator 63 to obtain a second voltage sampling value, and outputs the second voltage sampling value to the chip SG3525. The chip SG3525 can set a reference voltage and compare the reference voltage with the second voltage sampling value. Combined with the triangle wave generated by the chip SG3525, two PWM waves can be generated. The voltage regulator 63 is controlled by the two PWM waves so that the voltage output by the voltage regulator 63 to the DC-DC converter 4 is within a preset voltage range, such as 11-13V. In this way, the normal operation of the low-voltage load in the hybrid vehicle can be guaranteed.

It should be noted that if the output DC bus voltage is too low, the second voltage sampling value will be very small, then SG3525 can send a PWM wave with a larger duty cycle to boost the voltage.

Therefore, the auxiliary motor 5 and the DC-DC converter 4 have a separate regulated power supply channel. When the power battery 3 fails and is disconnected from the DC-DC converter 4, or the auxiliary motor controller 52 fails, the separate regulated power supply channel of the auxiliary motor 5 and the DC-DC converter 4 can be used to ensure low-voltage power consumption of the entire vehicle, ensure that the entire vehicle can achieve pure fuel mode driving, and improve the vehicle's mileage.

In a specific embodiment of the present invention, as shown in FIG5 , when the power battery 3 is damaged and disconnected from the DC-DC converter 4 , the voltage stabilizing circuit 6 is connected to the line input terminal of the DC-DC converter 4 .

The power motor 2 further includes a power motor controller 21, and the auxiliary motor controller 51 is connected to the power motor controller 21 and is connected to the DC-DC converter 4 via a voltage stabilizing circuit 6. When the auxiliary motor 5 generates electricity, the electric energy is converted by the inverter 511 into high-voltage direct current (HVDC), such as 600V HVDC, to power at least one of the power motor 2 and the DC-DC converter 4.

It can be understood that the power motor controller 21 may also have a DC-AC conversion unit, which can convert the high-voltage direct current output by the inverter 511 into alternating current to charge the power motor 4.

Specifically, as shown in Figure 5, the inverter 511 of the auxiliary motor controller 51 has a first DC terminal DC1, the power motor controller 21 has a second DC terminal DC2, and the DC-DC converter 4 has a third DC terminal DC3. The first DC terminal DC1 of the auxiliary motor controller 51 is connected to the third DC terminal DC3 of the DC-DC converter 4 via the voltage stabilizing circuit 6 to provide a stable voltage to the DC-DC converter 4, and the DC-DC converter 4 can perform DC-DC conversion on the stabilized DC power. In addition, the inverter 511 of the auxiliary motor controller 51 can also output high-voltage DC power to the power motor controller 21 via the first DC terminal DC1 to power the power motor 2.

Furthermore, as shown in FIG5 , the DC-DC converter 4 is also connected to the electrical device 10 and the low-voltage battery 20 in the hybrid vehicle respectively to supply power to the electrical device 10 and the low-voltage battery 20 , and the low-voltage battery 20 is also connected to the electrical device 10 .

Specifically, as shown in Figure 5, the DC-DC converter 4 further has a fourth DC terminal DC4. The DC-DC converter 4 can convert the high-voltage DC power output by the auxiliary motor 5 via the auxiliary motor controller 51 into low-voltage DC power, and output this low-voltage DC power through the fourth DC terminal DC4. The fourth DC terminal DC4 of the DC-DC converter 4 is connected to the electrical device 10 to power the electrical device 10. The electrical device 10 may be a low-voltage electrical device, including but not limited to vehicle lights, a radio, etc. The fourth DC terminal DC4 of the DC-DC converter 4 can also be connected to the low-voltage battery 20 to charge the low-voltage battery 20. The low-voltage battery 20 is connected to the electrical device 10 to power the electrical device 10. In particular, when the auxiliary motor 5 stops generating power, the low-voltage battery 20 can power the electrical device 10, thereby ensuring low-voltage power consumption for the entire vehicle, ensuring that the vehicle can operate in a purely fuel-powered mode, and improving the vehicle's mileage.

It should be noted that, in the embodiment of the present invention, low voltage may refer to a voltage of 12V (volts) or 24V, high voltage may refer to a voltage of 600V, and the preset voltage range may refer to 11~13V or 23~25V, but is not limited thereto.

In summary, according to the power system of the hybrid vehicle according to the embodiment of the present invention, the engine outputs power to the wheels of the hybrid vehicle through the clutch, the power motor outputs driving force to the wheels of the hybrid vehicle, the power battery supplies power to the power motor, the voltage stabilizing circuit stabilizes the DC power output to the DC-DC converter when the auxiliary motor generates electricity, and the second regulator controls the voltage stabilizing circuit to perform voltage stabilization when the power battery is disconnected from the DC-DC converter and the auxiliary motor controller is valid. The first regulator controls the voltage stabilizing circuit to perform voltage stabilization when the power battery is disconnected from the DC-DC converter and the auxiliary motor controller fails. This not only maintains the low-speed electrical balance and low-speed smoothness of the entire vehicle and improves the performance of the entire vehicle, but also can keep the input voltage of the DC-DC converter stable in the event of failure of the power battery or failure of both the power battery and the auxiliary motor controller, thereby ensuring the normal operation of the DC-DC converter and the normal driving of the entire vehicle.

Furthermore, the present invention also provides a hybrid vehicle.

Fig. 6 is a structural block diagram of a hybrid vehicle according to an embodiment of the present invention. As shown in Fig. 6 , a hybrid vehicle 200 includes the power system 100 of the hybrid vehicle described above.

The hybrid vehicle proposed in accordance with an embodiment of the present invention, through the power system of the hybrid vehicle, can not only maintain the low-speed electrical balance and low-speed smoothness of the entire vehicle, thereby improving the performance of the entire vehicle, but can also keep the input voltage of the DC-DC converter stable in the event of failure of the power battery or failure of both the power battery and the auxiliary motor controller, thereby ensuring the normal operation of the DC-DC converter and the normal driving of the entire vehicle.

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims (10)

1. A power system for a hybrid electric vehicle, characterized in that it comprises: An engine that delivers power to the wheels of the hybrid vehicle via a clutch; A power motor for outputting driving force to the wheels of the hybrid vehicle, the power motor including a power motor controller, the power motor controller including a first regulator; A power battery, which is used to supply power to the power motor; DC-DC converter; An auxiliary motor is connected to the engine, and the auxiliary motor is connected to the power motor, the DC-DC converter and the power battery respectively. The auxiliary motor includes an auxiliary motor controller, and the auxiliary motor controller includes an inverter and a second regulator. A voltage regulator circuit is connected between the auxiliary motor and the DC-DC converter. The voltage regulator circuit regulates the DC power output to the DC-DC converter when the auxiliary motor generates electricity. The second regulator is used to control the voltage regulator circuit to perform voltage regulation when the power battery is disconnected from the DC-DC converter and the auxiliary motor controller is active. The first regulator is used to control the voltage regulator circuit to perform voltage regulation when the power battery is disconnected from the DC-DC converter and the auxiliary motor controller fails. 2. The power system of the hybrid electric vehicle as claimed in claim 1, characterized in that the first regulator and the second regulator are both used to output a first regulation signal and a second regulation signal according to the output signal of the voltage regulator circuit, so as to keep the DC bus voltage output by the inverter stable, wherein the first regulation signal is used to regulate the d-axis current of the auxiliary motor, and the second regulation signal is used to regulate the q-axis current of the auxiliary motor. 3. The power system of the hybrid electric vehicle as described in claim 2, wherein the voltage regulator circuit includes a first voltage sampler and a target voltage acquisition unit, the first voltage sampler samples the DC bus voltage output by the inverter to obtain a first voltage sample value, and outputs the first voltage sample value to the first regulator or the second regulator, and the target voltage acquisition unit acquires a target reference voltage and sends the target reference voltage to the first regulator or the second regulator; Both the first regulator and the second regulator are used to output a first regulation signal and a second regulation signal based on the voltage difference between the target reference voltage and the first voltage sample value; The output signal of the voltage regulator circuit includes a first voltage sample value and a target reference voltage. 4. The power system of the hybrid electric vehicle as described in claim 3, wherein the voltage regulator circuit further comprises: A voltage regulator is connected to the DC output terminal of the inverter. The voltage regulator regulates the DC bus voltage output by the inverter. The output terminal of the voltage regulator is connected to the input terminal of the DC-DC converter. The second voltage sampler samples the output voltage of the regulator to obtain a second voltage sample value; A voltage regulator controller is connected to the voltage regulator and the second voltage sampler respectively. The voltage regulator controller is used to control the output voltage of the voltage regulator according to a preset reference voltage and the second voltage sample value so that the output voltage of the voltage regulator is within a preset voltage range. 5. The power system of a hybrid electric vehicle as described in claim 3, characterized in that both the first regulator and the second regulator comprise: An error calculation unit is connected to the first voltage sampler and the target voltage collector, respectively, and the error calculation unit is used to obtain the voltage difference between the target reference voltage and the first voltage sample value; A first PID control unit is connected to the error calculation unit. The first PID control unit adjusts the voltage difference between the target reference voltage and the first voltage sample value to output a first control signal. The second PID control unit is connected to the error calculation unit. The second PID control unit adjusts the voltage difference between the target reference voltage and the first voltage sample value to output a second control signal. 6. The power system of the hybrid electric vehicle as described in claim 1, wherein the auxiliary motor is a BSG motor. 7. The power system of the hybrid electric vehicle as claimed in claim 1, wherein when the auxiliary motor generates electricity under the drive of the engine, it achieves at least one of charging the power battery, supplying power to the power motor, and supplying power to the DC-DC converter. 8. The power system of a hybrid electric vehicle as claimed in claim 1, wherein the voltage regulator circuit is disposed on the output line of the auxiliary motor, wherein the auxiliary motor is connected to the power motor, the power battery and the DC-DC converter respectively through the voltage regulator circuit. 9. The power system of a hybrid electric vehicle as claimed in claim 1, wherein the voltage regulator circuit is disposed on the input line of the DC-DC converter, and the auxiliary motor is connected to the DC-DC converter and the power battery respectively. 10. A hybrid electric vehicle, characterized in that it includes the power system of a hybrid electric vehicle as described in any one of claims 1-9.