New energy automobile power assembly system comprising variable-frequency and variable-speed motor controller

Abstract

The invention relates to the technical field of new energy automobiles, in particular to a new energy automobile power assembly system with a variable-frequency and variable-speed motor controller, which comprises an automobile data detection module, a mapping relation establishing module and an output power adjusting module, the time in the current automobile running process is divided into a plurality of same time periods, then the road condition in the last same time period in the normal automobile running process is analyzed according to the change of the automobile running speed recorded by the automobile data detection module, and then the battery output power meeting the corresponding speed of the automobile in the current time period during running is called out. The problem that the automobile speed change amplitude is large is avoided, the driving comfort is improved through stable speed control, and by avoiding the too large automobile speed change amplitude, the jolting and pause feeling of the automobile in the driving process and the body discomfort brought to a driver and passengers due to sudden acceleration or deceleration are reduced.

Description

Technical Field

[0001] This invention relates to the field of new energy vehicle technology, and more specifically, to a new energy vehicle powertrain system containing a variable frequency speed control motor controller. Background Technology

[0002] With increasing global attention to environmental protection and sustainable development, new energy vehicles, as an important alternative to traditional fuel vehicles, are experiencing rapid development. New energy vehicles include various types such as pure electric vehicles and hybrid vehicles. Their core goal is to reduce dependence on fossil fuels, reduce exhaust emissions, and alleviate environmental pollution problems. Among the many components of new energy vehicles, the powertrain system undoubtedly plays the most critical role, as it directly determines the vehicle's power performance, energy efficiency, and driving experience.

[0003] In the complex system of new energy vehicles, the powertrain system undoubtedly occupies a key position at the core, just like the "heart" and "brain" of the car, directly affecting the car's power performance, energy efficiency, and driving experience.

[0004] Traditional powertrain systems typically operate by adjusting the battery output power based on the vehicle's real-time speed to drive the electric motor and provide the necessary power for continuous driving. However, in real-world driving scenarios, road conditions are complex and varied. To ensure driving safety and maintain speed, drivers often need to flexibly adjust the vehicle speed to cope with diverse road challenges. If the appropriate battery output power cannot be adjusted to control the vehicle speed according to different road conditions, the electric motor torque will fluctuate, resulting in an unstable ride and affecting the driving experience. Therefore, we propose a new energy vehicle powertrain system with a variable frequency speed control electric motor controller. Summary of the Invention

[0005] The purpose of this invention is to solve the problem of adjusting the driving speed to a suitable level when the speed adjustment range of a car is too large.

[0006] To achieve the above objectives, the present invention provides a new energy vehicle powertrain system containing a variable frequency speed control motor controller, including a vehicle data detection module, a mapping relationship establishment module, and an output power adjustment module;

[0007] The vehicle data detection module uses wheel speed sensors to detect vehicle speed and battery output power, then records the speed and battery output power at regular intervals, and uses a potentiometer to detect the accelerator pedal opening.

[0008] The mapping relationship establishment module is used to establish the mapping relationship between driving speed and battery output power;

[0009] The output power adjustment module is used to determine the desired speed of the car when starting, based on the accelerator pedal opening, and to retrieve the battery output power that matches the corresponding speed when the car starts, based on the mapping relationship in the mapping relationship establishment module.

[0010] Before the car starts driving normally, the driving time is divided into multiple equal time periods. During normal driving, the number of decelerations and accelerations in the previous time period is analyzed. Based on the number of decelerations and accelerations and multiple different speeds in the previous time period, the appropriate driving speed for normal driving is determined. The battery output power that matches the corresponding speed during normal driving is retrieved through the mapping relationship establishment module, and the driving speed during the car is adjusted.

[0011] As a further improvement to this technical solution, the vehicle data detection module uses wheel speed sensors to detect driving speed as follows:

[0012] The wheel speed sensor mainly consists of a permanent magnet and a coil;

[0013] According to the law of electromagnetic induction, when the magnetic flux passing through a closed coil changes, an induced electromotive force is generated in the coil. The magnitude of the induced electromotive force is proportional to the rate of change of the magnetic flux. In the wheel speed sensor, the permanent magnet generates a stable magnetic field, and the magnetic field lines pass through the coil.

[0014] After the car starts, the wheels drive the gear ring to rotate. The teeth and gaps of the gear ring alternately pass through the sensor. When the teeth are close to the sensor, because the teeth are made of metal, they change the distribution of the magnetic field, which increases the magnetic flux passing through the coil. When the gaps are close to the sensor, the magnetic flux decreases. The alternation of the teeth and gaps causes the magnetic flux to change periodically.

[0015] Due to the periodic change in magnetic flux, an induced electromotive force will be generated in the coil according to the law of electromagnetic induction. Moreover, since the teeth and gaps of the gear ring alternately pass through the sensor in a periodic process, the change in magnetic flux is also periodic, and the generated induced electromotive force is also periodic. The frequency of the induced electromotive force depends on the number of teeth on the gear ring and the rotational speed of the wheel.

[0016] As a further improvement to this technical solution, the steps for the vehicle data detection module to detect battery output power data are as follows:

[0017] Voltage is detected by a voltmeter, which mainly consists of a meter head and a measuring circuit. The meter head is a magnetoelectric ammeter, which contains a permanent magnet and a rotatable coil.

[0018] When a voltmeter is connected in parallel across the battery terminals, the battery voltage will generate a current in the voltmeter coil. According to Ampere's law, the current-carrying coil will be subjected to a force in the magnetic field and will rotate. The angle of rotation of the coil is proportional to the magnitude of the current passing through the coil, and the magnitude of this current is related to the voltage being measured, thus detecting the battery voltage.

[0019] Voltage and current are detected by a magnetoelectric ammeter, which consists of a permanent magnet, an iron core, a coil, a helical spring, a pointer, and a scale. The permanent magnet and the iron core constitute a magnetic field environment, and the coil is located in the magnetic field with its two ends connected to the terminals through the helical spring.

[0020] When the battery current flows into the coil through the terminal, the current is subjected to the Ampere force in the magnetic field. According to the left-hand rule, the coil will deflect, and the deflection angle is proportional to the magnitude of the current. The deflection of the coil causes the pointer to rotate on the scale, thus detecting the magnitude of the battery current.

[0021] Finally, the battery output power is calculated based on the battery voltage and current: Battery output power = voltage × current.

[0022] As a further improvement to this technical solution, the vehicle data detection module uses a potentiometer to detect the accelerator pedal opening as follows:

[0023] The minimum and maximum values ​​of the potentiometer output voltage correspond to 0% and 100% of the accelerator pedal opening, respectively.

[0024] When the car power is on but the accelerator pedal is not pressed, record the initial voltage value output by the potentiometer, which corresponds to an accelerator pedal opening of 0%.

[0025] When the accelerator pedal is pressed, the sliding contact moves on the potentiometer's resistive element, and then the change in voltage signal is measured to determine the degree of accelerator pedal opening.

[0026] The potentiometer output voltage range is V min -V max The corresponding accelerator pedal opening range is 0%-100%. The voltage signal V is measured, and the accelerator pedal opening L at this time is:

[0027]

[0028] As a further improvement to this technical solution, the steps of the mapping relationship establishment module in establishing the mapping relationship between driving speed and output power are as follows:

[0029] Receive n sets of data (v1, P1), (v2, P2), ..., (v...) recorded by the vehicle data detection module. n ,P n), where v is the driving speed, P is the vehicle battery output power, and n is the number of data sets for driving speed and battery output power;

[0030] The linear equation for the driving speed and the car battery output power is set as P = a × v + b;

[0031] Where a represents the average change in battery output power when the driving speed changes by one unit, and b represents the estimated value of battery output power when the driving speed v = 0;

[0032] Then, the coefficients a and b are determined using methods such as the least squares method. The calculation formula is as follows:

[0033]

[0034] in, For driving speed, This represents the average output power of the car battery.

[0035] As a further improvement to this technical solution, the steps for the output power adjustment module to adjust the battery output power to match the corresponding speed when the car starts are as follows:

[0036] Receives the driving speed v recorded periodically by the vehicle data detection module. a1 v a2 ... v an The accelerator pedal opening L corresponding to the driving speed;

[0037] And calculate the highest speed detected in the driving speed test: v a1 <v a 2 <...<v an This indicates that v an This is the maximum speed at which the vehicle can travel.

[0038] Calculate the speed v at Q% below the maximum speed. an-i =v an ×Q%;

[0039] Then, retrieve the data from the vehicle data detection module that matches v. an -v an-i The driving speeds between these values ​​represent the normal speed data set during normal vehicle operation: k1, k2, k3, ..., k n ;

[0040] Where k is the fastest speed and n is the number of speeds in the normal speed dataset;

[0041] Calculate the mean of the normal speed data set.

[0042] At this point, the speed the car wants to reach when starting is v. 速 =E×W%, where W% is the percentage of the mean of the fastest speed;

[0043] Based on the mapping relationship established in the module, the output power that meets the desired speed when the car starts is calculated:

[0044] P 符 =a×v 速 +b;

[0045] Among them, P 符 To match the battery output power required to reach the desired speed when the car starts, 'a' represents the average change in battery output power per unit change in driving speed, and 'b' represents the estimated battery output power when driving speed v = 0.

[0046] As a further improvement to this technical solution, the output power adjustment module divides the vehicle's driving time into multiple equal time periods as follows:

[0047] Receive the vehicle starting speed v recorded in the vehicle data detection module 起 and corresponding time;

[0048] Receive normal speed data set v an -v an- i,

[0049] Starting speed v 起 The speed v in the data set an The time difference between the corresponding time and the car's start time is used as the standard for dividing time periods.

[0050] As a further improvement to this technical solution, the steps of the output power adjustment module in analyzing the number of decelerations and accelerations in the previous time period are as follows:

[0051] Receive the driving speed at the adjacent time point in the previous time period corresponding to the current time period:

[0052] (v1, t1), (v2, t2), (v3, t3), ..., (v n , t n );

[0053] Among them, v1-v n This indicates the time interval corresponding to t1-t in the previous time period. n The driving speed, t1 and t n This refers to the start and end times of the previous time period;

[0054] When v1 > v2, it means that the speed at time t1 is greater than the speed at time t2, and the driving speed is in a deceleration state at this time.

[0055] If v2 < v3, it means that the speed at time t2 is greater than the speed at time t3, and the driving speed is in an acceleration state at this time.

[0056] t1-t n By comparing each instance, the number of times deceleration and acceleration occurred can be determined.

[0057] As a further improvement to this technical solution, the steps for adjusting the output power adjustment module to match the battery output power at the corresponding speed when the car is driving normally are as follows:

[0058] Receives the number of decelerations, the number of accelerations, and multiple driving speeds at adjacent time points within the previous time period;

[0059] Multiple travel speeds: t1, t2, t3, ..., t n If t n If > ... > t3 > t2 > t1, then it means t n This represents the maximum speed within the previous time period.

[0060] If the number of decelerations is less than or equal to the number of accelerations, then the appropriate speed is A% of the maximum speed in the previous time period;

[0061] If the number of decelerations is greater than the number of accelerations, then the appropriate speed is B% of the maximum speed in the previous time period.

[0062] And A% > B%;

[0063] If the number of decelerations is less than or equal to the number of accelerations, and the number of accelerations minus the number of decelerations is less than C, then the output power should be adjusted.

[0064] When the number of decelerations is less than or equal to the number of accelerations, the suitable speed is: A a =t n ×A%;

[0065] The power adjusted at this time is: P D =a×A a +b;

[0066] When the number of decelerations is greater than the number of accelerations, the appropriate speed is: A b =t n ×B%;

[0067] Based on the mapping relationship established, the mapping relationship between driving speed and output power in the module is calculated, and the battery output power corresponding to the appropriate speed is: P f =a×A b +b;

[0068] Among them, PD P is the battery output power when the number of decelerations is less than or equal to the number of accelerations. f Battery output power A when deceleration count > acceleration count a and A b These represent the suitable speeds for the current time period when the number of decelerations is less than or equal to the number of accelerations and when the number of decelerations is greater than or equal to the number of accelerations, respectively. 'a' represents the average change in battery output power for each unit change in driving speed, and 'b' represents the estimated battery output power when driving speed v = 0.

[0069] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0070] In this new energy vehicle powertrain system containing a variable frequency speed control motor controller, the output power adjustment module analyzes the vehicle's historical driving speed during normal driving. Based on the normal driving speed and the mapping relationship established by the module, the battery output power is adjusted to match the vehicle's starting speed. This provides sufficient power for the vehicle's starting speed, effectively improving the starting response speed and smoothness. When the driver presses the accelerator pedal to start, the output power adjustment module quickly adjusts the appropriate power, enabling the motor to output sufficient torque in time to overcome the vehicle's stationary inertia and allow the vehicle to start smoothly and quickly.

[0071] Then, the output power adjustment module divides the current driving time into multiple equal time periods based on the speed during normal driving. Then, by analyzing the changes in the car's driving speed recorded by the car data detection module, it analyzes the road conditions in the previous equal time period during normal driving. Finally, it retrieves the battery output power corresponding to the current driving time period and speed, avoiding the problem of large speed fluctuations. Stable speed control improves driving comfort. By avoiding excessive speed fluctuations, it reduces the bumps, jerks, and physical discomfort caused to the driver and passengers during driving. Attached Figure Description

[0072] Figure 1 This is a schematic diagram of the overall module of the present invention.

[0073] The meanings of the labels in the diagram are as follows:

[0074] 100. Vehicle data detection module; 200. Mapping relationship establishment module; 300. Output power adjustment module. Detailed Implementation

[0075] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0076] A new energy vehicle powertrain system with a variable frequency speed control motor controller includes a vehicle data detection module 100, a mapping relationship establishment module 200, and an output power adjustment module 300.

[0077] The vehicle data detection module 100 uses wheel speed sensors to detect the vehicle speed and the battery output power, then records the speed and battery output power at regular intervals, and uses a potentiometer to detect the opening of the accelerator pedal.

[0078] Specifically, the steps by which the vehicle data detection module 100 uses wheel speed sensors to detect driving speed are as follows:

[0079] The wheel speed sensor mainly consists of a permanent magnet and a coil;

[0080] According to the law of electromagnetic induction, when the magnetic flux passing through a closed coil changes, an induced electromotive force is generated in the coil. The magnitude of the induced electromotive force is proportional to the rate of change of the magnetic flux. In the wheel speed sensor, the permanent magnet generates a stable magnetic field, and the magnetic field lines pass through the coil.

[0081] After the car starts, the wheels drive the gear ring to rotate. The teeth and gaps of the gear ring alternately pass through the sensor. When the teeth are close to the sensor, because the teeth are made of metal, they change the distribution of the magnetic field, which increases the magnetic flux passing through the coil. When the gaps are close to the sensor, the magnetic flux decreases. The alternation of the teeth and gaps causes the magnetic flux to change periodically.

[0082] Due to the periodic change in magnetic flux, an induced electromotive force will be generated in the coil according to the law of electromagnetic induction. Moreover, since the teeth and gaps of the gear ring alternately pass through the sensor in a periodic process, the change in magnetic flux is also periodic, and the generated induced electromotive force is also periodic. The frequency of the induced electromotive force depends on the number of teeth on the gear ring and the rotational speed of the wheel.

[0083] The number of teeth on the receiving gear ring is J, the wheel speed is L, and the number of teeth the wheel rotates per second is...

[0084] Because the magnetic flux changes by one cycle with each tooth it passes, the frequency of the induced electromotive force is...

[0085] At this time, the wheel speed

[0086] Then, the driving speed is calculated based on the wheel rotation speed and wheel radius: Where r is the radius of the wheel.

[0087] Secondly, the steps taken by the vehicle data detection module 100 to detect battery output power data are as follows:

[0088] Voltage is detected by a voltmeter, which mainly consists of a meter head and a measuring circuit. The meter head is a magnetoelectric ammeter, which contains a permanent magnet and a rotatable coil.

[0089] When a voltmeter is connected in parallel across the battery terminals, the battery voltage will generate a current in the voltmeter coil. According to Ampere's law, the current-carrying coil will be subjected to a force in the magnetic field and will rotate. The angle of rotation of the coil is proportional to the magnitude of the current passing through the coil, and the magnitude of this current is related to the voltage being measured, thus detecting the battery voltage.

[0090] Voltage and current are detected by a magnetoelectric ammeter, which consists of a permanent magnet, an iron core, a coil, a helical spring, a pointer, and a scale. The permanent magnet and the iron core constitute a magnetic field environment, and the coil is located in the magnetic field with its two ends connected to the terminals through the helical spring.

[0091] When the battery current flows into the coil through the terminal, the current is subjected to the Ampere force in the magnetic field. According to the left-hand rule, the coil will deflect, and the deflection angle is proportional to the magnitude of the current. The deflection of the coil causes the pointer to rotate on the scale, thus detecting the magnitude of the battery current.

[0092] Finally, the battery output power is calculated based on the battery voltage and current: Battery output power = voltage × current.

[0093] Furthermore, the vehicle data detection module 100 uses a potentiometer to detect the accelerator pedal opening in the following steps:

[0094] The minimum and maximum values ​​of the potentiometer output voltage correspond to 0% and 100% of the accelerator pedal opening, respectively.

[0095] When the car power is on but the accelerator pedal is not pressed, record the initial voltage value output by the potentiometer, which corresponds to an accelerator pedal opening of 0%.

[0096] When the accelerator pedal is pressed, the sliding contact moves on the potentiometer's resistive element, and then the change in voltage signal is measured to determine the degree of accelerator pedal opening.

[0097] The potentiometer output voltage range is V min -V maxThe corresponding accelerator pedal opening range is 0%-100%. The voltage signal V is measured, and the accelerator pedal opening L at this time is:

[0098]

[0099] The accelerator pedal opening essentially controls the power entering the electric motor, thereby affecting the motor's torque output and ultimately changing the car's speed. The accelerator pedal opening is positively correlated with the car's speed. When the accelerator pedal opening is 0, the car is idling or not providing additional power, and the speed remains at a low level, such as the coasting speed of a pure electric vehicle or the idling speed of a traditional fuel vehicle. As the accelerator pedal opening gradually increases, the battery output power increases, the electric motor torque increases, and the car speed increases accordingly.

[0100] The mapping relationship establishment module 200 is used to establish the mapping relationship between driving speed and battery output power;

[0101] By establishing a mapping relationship between driving speed and battery output power, the most suitable battery output power for the vehicle's real-time driving speed can be accurately determined. Therefore, the steps of the mapping relationship establishment module 200 in establishing the mapping relationship between driving speed and output power are as follows:

[0102] Receive n sets of data (v1, P1), (v2, P2), ..., (v...) recorded by the vehicle data detection module 100 n ,P n ), where v is the driving speed, P is the vehicle battery output power, and n is the number of data sets for driving speed and battery output power;

[0103] The linear equation for the driving speed and the car battery output power is set as P = a × v + b;

[0104] Where a represents the average change in battery output power when the driving speed changes by one unit, and b represents the estimated value of battery output power when the driving speed v = 0;

[0105] Then, the coefficients a and b are determined using methods such as the least squares method. The calculation formula is as follows:

[0106]

[0107] in, For driving speed, This represents the average output power of the car battery.

[0108] This invention addresses the issue that, during the start-up process of new energy vehicles, drivers often want to quickly increase vehicle speed, so they press the accelerator pedal to increase the opening. However, such operation will cause the battery to output excessively high power at once, putting the battery under high load and affecting its lifespan. On the other hand, excessively high power output may cause instability in the vehicle's power system, such as excessive instantaneous current in the motor and increased heat generation. Moreover, if the battery output power is not adjusted in advance to match the desired speed before pressing the accelerator pedal, it is difficult to achieve a smooth and efficient start-up. This invention solves the problems caused by the above situations through the output power adjustment module 300.

[0109] The output power adjustment module 300 is used to determine the desired speed of the car when starting, based on the accelerator pedal opening, and to retrieve the battery output power that matches the car's starting speed according to the mapping relationship established in module 200. Therefore, the steps of the output power adjustment module 300 in retrieving the battery output power that matches the car's starting speed are as follows:

[0110] The vehicle data detection module 100 receives the driving speed v recorded periodically. a1 v a2 ... v an The accelerator pedal opening L corresponding to the driving speed;

[0111] And calculate the highest speed detected in the driving speed test: v a1 <v a2 <...<v an This indicates that v an This is the maximum speed at which the vehicle can travel.

[0112] Calculate the speed v at Q% below the maximum speed. an-i =v an ×Q%;

[0113] Then, retrieve the vehicle data detection module 100 that matches v. an -v an-i The driving speeds between these values ​​represent the normal speed data set during normal vehicle operation: k1, k2, k3, ..., k n ;

[0114] Where k is the fastest speed and n is the number of speeds in the normal speed dataset;

[0115] Calculate the mean of the normal speed data set.

[0116] At this point, the speed the car wants to reach when starting is v. 速 =E×W%, where W% is the percentage of the mean of the fastest speed;

[0117] Based on the mapping relationship established in module 200, the output power that meets the desired speed when the car starts is calculated:

[0118] P 符 =a×v 速 +b;

[0119] Among them, P 符 To match the battery output power required to reach the desired speed when the car starts, 'a' represents the average change in battery output power per unit change in driving speed, and 'b' represents the estimated battery output power when driving speed v = 0.

[0120] By adjusting the appropriate battery output power in advance, the car can achieve smoother and faster acceleration during the start-up phase, avoiding problems such as start-up jerking or power delay caused by unreasonable power output. At the same time, reasonable control of battery power output can prevent the battery from bearing too high a load during start-up, which helps to extend battery life, reduce car maintenance costs, and provide the car with the output power required to reach the starting speed.

[0121] Furthermore, the output power adjustment module 300 divides the vehicle's driving time into multiple equal time periods using the following steps:

[0122] The vehicle's starting speed v is recorded in the vehicle data detection module 100. 起 and corresponding time;

[0123] Receive normal speed data set v an -v an- i,

[0124] Starting speed v 起 The speed v in the data set an The time difference between the corresponding time and the car's start time is used as the standard for dividing time periods;

[0125] During driving, this method of dividing time periods can be used to judge road conditions based on speed changes within each time period. For example, in urban congestion, speed changes frequently within each time period, and the car may reach different "maximum speeds" multiple times in a short period of time. By analyzing the speed characteristics of these time periods, it can be determined that the car is in complex urban road conditions. Then, based on the mapping relationship, the battery output power can be frequently adjusted to control the car speed, enabling the car speed to better adapt to frequent starts, stops, accelerations, and decelerations.

[0126] In order to analyze the deceleration and acceleration times in the previous time period based on the driver's operating intentions, the output power adjustment module 300 analyzes the following steps:

[0127] Receive the driving speed at the adjacent time point in the previous time period corresponding to the current time period:

[0128] (v1, t1), (v2, t2), (v3, t3), ..., (v n , t n );

[0129] Among them, v1-v n This indicates the time interval corresponding to t1-t in the previous time period. n The driving speed, t1 and t n This refers to the start and end times of the previous time period;

[0130] When v1 > v2, it means that the speed at time t1 is greater than the speed at time t2, and the driving speed is in a deceleration state at this time.

[0131] If v2 < v3, it means that the speed at time t2 is greater than the speed at time t3, and the driving speed is in an acceleration state at this time.

[0132] t1-t n By comparing each instance, the number of times deceleration and acceleration occurred can be determined.

[0133] The present invention also takes into account that new energy vehicles will face various road conditions during actual driving, such as congested urban roads, highways, and rugged rural roads. For example, on congested urban roads, the car needs to start and stop, accelerate and decelerate significantly. At this time, the powertrain system is required to respond quickly to the driver's operating intentions and maintain high efficiency under low speed and low load conditions.

[0134] Before the car starts driving normally, the driving time is divided into multiple equal time periods. During normal driving, the number of decelerations and accelerations in the previous time period is analyzed. Based on the number of decelerations and accelerations and the multiple different speeds in the previous time period, the appropriate driving speed for normal driving is determined. Then, the battery output power corresponding to the normal driving speed is retrieved through the mapping relationship in the mapping relationship module 200. The driving speed is adjusted during the driving process. Therefore, the steps of the output power adjustment module 300 to retrieve the battery output power corresponding to the normal driving speed are as follows:

[0135] Receives the number of decelerations, the number of accelerations, and multiple driving speeds at adjacent time points within the previous time period;

[0136] Multiple travel speeds: t1, t2, t3, ..., t n If t n If > ... > t3 > t2 > t1, then it means t n This represents the maximum speed within the previous time period.

[0137] If the number of decelerations is less than or equal to the number of accelerations, then the appropriate speed is A% of the maximum speed in the previous time period;

[0138] When driving on a highway with moderate traffic flow, flat road surface, and few unexpected situations, vehicles may only occasionally accelerate slightly to overtake or slow down slightly to give way, but the overall speed does not change much. This indicates that the road conditions are relatively good, the vehicle is in a relatively smooth driving state, and there are more opportunities to increase speed rather than frequent braking and deceleration.

[0139] If the number of decelerations is greater than the number of accelerations, then the appropriate speed is B% of the maximum speed in the previous time period.

[0140] On main roads during rush hour, traffic volume is extremely high, and the distance between vehicles is very small. Drivers need to constantly brake to slow down and avoid colliding with the vehicle in front. They can only accelerate briefly when the traffic flow eases slightly, and even then, the acceleration is very limited because they will soon encounter another congestion point and have to slow down again. This frequent deceleration and occasional small acceleration means that the number of decelerations is significantly more than the number of accelerations, indicating that the road conditions are congested and vehicles are unable to move smoothly.

[0141] And A% > B%;

[0142] If the number of decelerations is less than or equal to the number of accelerations, and the number of accelerations minus the number of decelerations is less than C, then the output power will not be adjusted.

[0143] Driving at a constant speed on a highway with moderate traffic and good road conditions, occasionally accelerating or decelerating slightly to overtake or make minor adjustments to speed, indicates that the road conditions are normal.

[0144] When the number of decelerations is less than or equal to the number of accelerations, the suitable speed is: A a =t n ×A%;

[0145] The power adjusted at this time is: P D =a×A a +b;

[0146] When the number of decelerations is greater than the number of accelerations, the appropriate speed is: A b =t n ×B%;

[0147] Based on the mapping relationship established in module 200, the mapping relationship between driving speed and output power is calculated, and the battery output power corresponding to the appropriate speed is: P f =a×A b +b;

[0148] Among them, P D P is the battery output power when the number of decelerations is less than or equal to the number of accelerations. fBattery output power A when deceleration count > acceleration count a and A b These represent the appropriate speeds for the current time period when the number of decelerations is less than or equal to the number of accelerations and when the number of decelerations is greater than or equal to the number of accelerations. 'a' represents the average change in battery output power when the driving speed changes by one unit, and 'b' represents the estimated value of battery output power when the driving speed v = 0. The driving speed of the car is adjusted by adjusting the battery output power.

[0149] By rationally determining the appropriate driving speed and adjusting the corresponding battery output power, the car's electric motor can adjust to the appropriate speed for different road conditions, making the motor's speed and torque output more reasonable. Under different speed and torque requirements, the electric motor receives the appropriate electrical energy input, avoiding the problem of low efficiency caused by excessive or insufficient power.

[0150] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A new energy vehicle powertrain system including a variable frequency speed regulating motor controller, characterized in that: It comprises an automobile data detection module (100), a mapping relationship establishment module (200) and an output power adjustment module (300); The vehicle data detection module (100) uses a wheel speed sensor to detect the vehicle's driving speed and battery output power, then records the driving speed and battery output power at regular intervals, and detects the opening of the accelerator pedal through a potentiometer; The mapping relationship establishing module (200) is used to establish a mapping relationship between driving speed and battery output power; The output power adjustment module (300) is used to determine the desired speed of the vehicle when the vehicle starts according to the accelerator pedal opening when the vehicle starts, and to adjust the battery output power that meets the corresponding speed when the vehicle starts according to the mapping relationship in the mapping relationship establishment module (200); Before the car starts to run normally, the car's running time is divided into a plurality of equal time periods. When the car is running normally, the number of deceleration and acceleration in the previous time period is analyzed. According to the number of deceleration and acceleration and a plurality of different speeds in the previous time period, the appropriate driving speed of the car during normal running is determined. The mapping relationship in the mapping relationship establishment module (200) is used to call out the battery output power that meets the corresponding speed of the car during normal running, and adjust the driving speed of the car during driving.

2. The new energy vehicle powertrain system including a variable frequency speed regulating motor controller according to claim 1 is characterized in that: The steps of the vehicle data detection module (100) detecting the driving speed using the wheel speed sensor are as follows: The wheel speed sensor is mainly composed of a permanent magnet and a coil; According to the law of electromagnetic induction, when the magnetic flux passing through a closed coil changes, an induced electromotive force will be generated in the coil. The magnitude of the induced electromotive force is proportional to the rate of change of the magnetic flux. In the wheel speed sensor, the permanent magnet generates a stable magnetic field, and the magnetic lines of force of the magnetic field will pass through the coil. After the car starts, the wheels drive the gear ring to rotate, and the teeth and gaps of the gear ring alternately pass through the sensor. When the teeth are close to the sensor, since the teeth are made of metal, they will change the distribution of the magnetic field, increasing the magnetic flux passing through the coil. When the gap is close to the sensor, the magnetic flux will decrease. The alternating changes of teeth and gaps cause the magnetic flux to change periodically. Due to the periodic change of magnetic flux, according to the law of electromagnetic induction, an induced electromotive force will be generated in the coil. Moreover, because the teeth and gaps of the ring gear alternately pass through the sensor in a periodic process, the change of magnetic flux is also periodic, and the induced electromotive force generated is also periodic. The frequency of the induced electromotive force depends on the number of teeth of the ring gear and the rotation speed of the wheel.

3. The new energy vehicle powertrain system including a variable frequency speed regulating motor controller according to claim 1 is characterized in that: The steps of the automobile data detection module (100) detecting battery output power data are as follows: The detection voltage is detected by a voltmeter, which is mainly composed of a meter head and a measuring circuit. The meter head is a magnetoelectric ammeter, which has a permanent magnet and a rotatable coil inside. When the voltmeter is connected in parallel to the two ends of the battery, the voltage of the battery will generate current in the meter coil. According to Ampere's law, the energized coil will rotate due to the force in the magnetic field. The angle of rotation of the coil is proportional to the current passing through the coil, and the current is related to the voltage being measured, thereby detecting the voltage of the battery. The voltage and current are detected by a magnetoelectric ammeter, which is composed of a permanent magnet, an iron core, a coil, a spiral spring, a pointer, a dial, etc., wherein the permanent magnet and the iron core constitute a magnetic field environment, the coil is located in the magnetic field and both ends are connected to the terminal through a spiral spring; When the battery current flows into the coil through the terminal, the current is acted upon by the Ampere force in the magnetic field. According to the left-hand rule, the coil will deflect, and the deflection angle is proportional to the current. The deflection of the coil drives the pointer to rotate on the dial, detecting the battery current. Finally, the battery output power is calculated based on the battery voltage and current: battery output power = voltage × current.

4. The new energy vehicle powertrain system including a variable frequency speed regulating motor controller according to claim 1 is characterized in that: The steps of the automobile data detection module (100) using a potentiometer to detect the accelerator pedal opening are as follows: The minimum and maximum values ​​of the potentiometer output voltage correspond to 0% and 100% of the accelerator pedal opening respectively; When the car power is turned on but the accelerator pedal is not pressed, record the initial voltage value output by the potentiometer, corresponding to the accelerator pedal opening of 0%; When the accelerator pedal is depressed, the sliding contact moves on the potentiometer resistance element, and then the change in the voltage signal is measured to determine the opening of the accelerator pedal; The output voltage range of the potentiometer is V min -V max , the corresponding accelerator pedal opening range is 0%-100%, and the voltage signal V is measured. At this time, the accelerator pedal opening L is:

5. The new energy vehicle powertrain system including a variable frequency speed regulating motor controller according to claim 4 is characterized in that: The steps of the mapping relationship establishing module (200) establishing the mapping relationship between the driving speed and the output power are as follows: Receive n groups of data (v1, P1), (v2, P2), ..., (v n ,P n ), where v is the driving speed, P is the output power of the vehicle battery, and n is the number of driving speed and battery output power data sets; Set the linear equation of driving speed and car battery output power to P = a × v + b; Where a represents the average change in battery output power when the driving speed changes by one unit, and b represents the estimated value of battery output power when the driving speed v = 0; Then the coefficients a and b are determined by the least squares method and the calculation formula is as follows: in, is the driving speed, is the average value of the car battery output power.

6. The new energy vehicle powertrain system including a variable frequency speed regulating motor controller according to claim 5 is characterized in that: The steps of the output power adjustment module (300) adjusting the battery output power corresponding to the speed when the vehicle starts are as follows: Receive the driving speed v recorded regularly in the automobile data detection module (100) a1 、v a2 ,...,v an The accelerator pedal opening L corresponding to the driving speed; And calculate the highest speed among the detected driving speeds: v a1 <v a2 <...<v an , then it means v an is the maximum speed of travel; Calculate the speed v at Q% below the maximum speed an-i =v an ×Q%; Then, the vehicle data detection module (100) is retrieved to find the vehicle data that meets the requirements of v an -v an-i The driving speed between is the normal speed data set of the car during normal driving: k1, k2, k3, ..., k n ; Where k is the fastest speed, and n is the number of speeds in the normal speed data set; Calculate the mean of the normal speed data set At this time, the speed that the car wants to achieve when it starts is v 速 =E×W%, where W% is the percentage of the mean of the fastest speed; The output power that meets the speed that the vehicle wants to achieve when starting is calculated according to the mapping relationship in the mapping relationship establishment module (200): P 符 =a×v 速 +b; Among them, P 符 In order to meet the battery output power required to achieve the speed when the car starts, a represents the average change in battery output power for each unit change in driving speed, and b represents the estimated value of battery output power when driving speed v=0.

7. The new energy vehicle powertrain system including a variable frequency speed regulating motor controller according to claim 6 is characterized in that: The steps of the output power adjustment module (300) dividing the vehicle driving time into a plurality of equal time periods are as follows: Receive the vehicle starting speed v recorded in the vehicle data detection module (100) 起 and corresponding time; Receive normal speed data set v an -v an -i, Starting speed 起 Arrival speed v in the data set an The time difference between the corresponding time and the car's starting time is the standard for dividing time periods.

8. The new energy vehicle powertrain system including a variable frequency speed regulating motor controller according to claim 7 is characterized in that: The steps of the output power adjustment module (300) analyzing the number of deceleration and acceleration times in the previous time period are as follows: Receive the driving speed at adjacent time points in the previous time period corresponding to the current time period: (v1, t1)、(v2, t2)、(v3, t3)、...、(v n ,t n ); Among them, v1-v n Indicates the last time period corresponding to t1-t n The driving speed, t1 and t n The start time and end time of the previous time period; When v1>v2, it means that the speed at time t1 is greater than the speed at time t2, and the driving speed is in a deceleration state; v2<v3, which means that the speed at time t2 is greater than the speed at time t3, and the driving speed is in an accelerated state at this time; t1-t n Compare them one by one to find out the number of deceleration and acceleration.

9. The new energy vehicle powertrain system including a variable frequency speed regulating motor controller according to claim 8 is characterized in that: The steps of the output power adjustment module (300) adjusting the battery output power corresponding to the speed when the vehicle is running normally are as follows: Receive the number of decelerations, the number of accelerations, and multiple driving speeds at adjacent time points in the previous time period; Multiple driving speeds: t1, t2, t3, ..., t n , if t n >...>t3>t2>t1, which means t n is the maximum speed in the previous time period; If the number of decelerations is less than or equal to the number of accelerations, the appropriate speed is A% of the maximum speed in the previous time period; If the number of decelerations is greater than the number of accelerations, the appropriate speed is B% of the maximum speed in the previous time period; and A%>B%; If the number of decelerations is less than or equal to the number of accelerations, and the number of accelerations - the number of decelerations is less than C, the output power is adjusted; When the number of decelerations is less than or equal to the number of accelerations, the appropriate speed is: A a =t n ×A%; The adjusted power at this time is: P D =a×A a +b; When the number of decelerations is greater than the number of accelerations, the appropriate speed is: A b =t n ×B%; According to the mapping relationship between the driving speed and the output power in the mapping relationship establishment module (200), the battery output power corresponding to the appropriate speed is calculated as: P f =a×A b +b; Among them, P D P is the battery output power when the number of deceleration times ≤ the number of acceleration times, f Battery output power when deceleration times > acceleration times, A a and A b They are the appropriate speeds for the current time period when the number of decelerations ≤ the number of accelerations and the number of decelerations > the number of accelerations, respectively. a represents the average change in battery output power when the driving speed changes by one unit. b represents the estimated value of the battery output power when the driving speed v = 0.

Images