A constant speed cruise control method and control system

Abstract

The present invention discloses a constant-speed cruise control method and control system that can be controlled by arbitrary speed signals. The present invention obtains a first reference voltage by collecting real-time speed signals during the operation of a driving device; a user sets a target speed voltage for uniform driving and inputs a feedback signal voltage for vehicle throttle control at the same time, and a second reference voltage is obtained after combining the target speed voltage and the feedback signal voltage; the first reference voltage and the second reference voltage are input into a signal comparison unit for comparison, and a signal is generated after comparison and sent to a signal modulation unit; in the fourth step: the signal modulation unit generates a feedback signal to the control unit, causing the control unit to perform operations of increasing speed, decreasing speed, or maintaining a constant speed. By adopting real-time dynamic frequency conversion tracking and signal acquisition, the running speed of the driving device can be increased or decreased freely, the signal is instantaneously calibrated, and the running speed of the device is accurately ensured to remain constant, enabling the vehicle to stably maintain a state of uniform driving.

Description

Technical Field

[0001] The present invention relates to the technical field of cruise control, and particularly to a cruise control method and control system that can be controlled by any speed signal. Background Art

[0002] With the development of automotive intelligence, the automatic cruise function of automobiles has been widely applied in automotive assisted driving functions. The current automatic cruise function of automobiles mainly analyzes the vehicle speed signal collected by the in-vehicle computer of the automobile, adjusts the current vehicle speed to be consistent with the target vehicle speed (set cruise vehicle speed), and adjusts the vehicle speed in real time to achieve uniform driving.

[0003] The existing cruise control method needs to collect multiple relevant data and compare the collected data with the set data signal. In circuit implementation, multiple controllers need to be used, resulting in a relatively complex circuit setup. For example, see the Chinese invention patent specification with the patent number: 201410671694.1. The disclosed cruise control system includes a first microprocessing module Ⅰ connected to the engine ECU unit. The first microprocessing module Ⅰ is connected to the cruise switch. The engine ECU unit is connected to a second microprocessing module Ⅱ through the CAN bus. A speed sensor is connected to the second microprocessing module Ⅱ. The cruise control method is that the second microprocessing module Ⅱ receives the vehicle speed signal and transmits it to the engine ECU unit through the CAN bus. At the same time, the engine ECU unit receives the control signal, clutch signal, brake signal, and exhaust brake signal, and analyzes these signals. When the cruise control condition is met, the engine ECU unit controls the vehicle speed state according to the control requirements, and at the same time transmits this cruise control state signal to the second microprocessing module Ⅱ to control the working state of the indicator light.

[0004] The above cruise control system and method are too complex. After long-term experiments, the inventor of the present invention has proposed the following technical solutions to simplify the system. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a cruise control method and control system with simple operation and simplified circuit.

[0006] To solve the above technical problems, the constant speed cruise control method of the present invention adopts the following technical solutions: The method includes the following steps: First step: Collect the real-time speed signal of the driving device during operation. After converting the collected real-time speed signal into a voltage signal and selecting and separating it through the signal selection and separation unit, a first reference voltage is obtained through the signal amplification unit and the secondary filtering unit; Second step: The user sets the target speed voltage required for uniform driving, and at the same time inputs the feedback signal voltage of vehicle throttle control. After combining the target speed voltage and the feedback signal voltage, a second reference voltage is obtained; Third step: Input the first reference voltage and the second reference voltage into the signal comparison unit for comparison, and generate a signal to the signal modulation unit through the comparison; Fourth step: The signal modulation unit generates a feedback signal to the control unit, causing the control unit to perform operations of increasing speed, decreasing speed, or maintaining a constant speed.

[0007] Furthermore, in the above constant speed cruise control method, the signal comparison unit includes two operational comparators. When the first reference voltage and the second reference voltage are compared, these two reference voltages will be input into the two operational comparators in positive and negative directions simultaneously, that is, these two reference voltages simultaneously perform speed increase comparison and speed decrease comparison through the two operational comparators.

[0008] Furthermore, in the above constant speed cruise control method, the merging method of the target speed voltage and the feedback signal voltage in the second step is as follows: The target speed voltage and the feedback signal voltage are connected in parallel. When the feedback signal voltage is lower than the target speed voltage, the target speed voltage will backflow into the lower feedback signal voltage, and the two voltages are combined and input into the signal comparison unit as the second reference voltage; when the feedback signal voltage is higher than the target speed voltage, the feedback signal voltage will be input into the target speed voltage, and the two voltages are combined and input into the signal comparison unit as the second reference voltage.

[0009] Furthermore, in the above constant speed cruise control method, in the first step, the real-time speed signal of the driving device during operation includes one or a combined signal such as a Hall signal, a rotational speed signal, a frequency signal, a PWM pulse signal, etc.; after the speed signal of the driving device during operation passes through the signal conversion unit, the signal is filtered by the conversion unit, and through opto-isolation, the signal is converted into a voltage signal and input into the signal selection and separation unit for selection and separation.

[0010] The constant speed cruise control system of the present invention adopts the following technical solutions: A constant speed cruise control system, which includes: a signal acquisition unit for acquiring real-time speed signals during the operation of the driving device, a signal conversion unit, a signal selection and separation unit, a signal amplification unit, a signal comparison unit, a signal modulation unit, a motor control unit, a secondary filtering unit, a target speed voltage input unit, and a power supply unit for supplying power to each circuit; the signal acquisition unit inputs the signals acquired during the operation of the driving device to the signal conversion unit through a first interface, converts the signals into voltage signals and inputs them to the signal selection and separation unit; the signal amplification unit includes an operational amplifier, and the real-time signal output by the signal selection and separation unit is amplified by the operational amplifier and then filtered by the secondary filtering unit and input to the signal comparison unit as a first reference voltage; the target speed voltage input unit and the feedback signal voltage controlled by the vehicle throttle input through the first interface are connected in parallel and input to the signal comparison unit as a second reference voltage; the signal comparison unit includes two operational comparators, the first reference voltage and the second reference voltage are simultaneously input to the two operational comparators, and the input positions of the first reference voltage and the second reference voltage to the two operational comparators are opposite; the signal modulation unit includes two parallel optocouplers, and the two optocouplers are respectively connected to the two operational comparators in the signal comparison unit, and

[0011] the amplified output ends of the two operational comparators are respectively connected to the optocouplers in the signal modulation unit.

[0012] Furthermore, in the above constant speed cruise control system, the speed signals of the signal acquisition unit during operation include Hall signals, rotational speed signals, frequency signals, PWM pulse signals, etc., one or a combination of signals.

[0013] Furthermore, in the above constant speed cruise control system, the signal conversion unit includes: a first filtering circuit connected to the first interface, and an optocoupler connected to the filtering circuit. After the speed signal acquired by the signal acquisition unit is filtered by the first filtering circuit, it is optically isolated by the optocoupler, and the speed signal is converted into a voltage signal and input to the signal selection and separation unit for selection and separation.

[0014] Furthermore, in the above constant speed cruise control system, the signal selection and separation unit includes a frequency-voltage conversion chip and a voltage stabilizing chip for supplying power to it.

[0015] Furthermore, in the above constant speed cruise control system, in the secondary filtering unit, the signal is filtered and stabilized through a buck-boost power supply control chip and a voltage stabilizing circuit.

[0016] Furthermore, in the above cruise control system, the signal modulation unit includes a capacitor for storing the signal voltage.

[0017] After adopting the above technical solution, the present invention has the following beneficial effects compared with the prior art: The present invention simplifies the data acquisition solution. After arbitrarily acquiring a vehicle speed signal and processing the signal, it is used as the first reference voltage to be compared with the second reference voltage, and the second reference voltage is obtained by combining the target speed voltage and the feedback signal voltage of the throttle control. The signal comparison unit for comparing the first reference voltage and the second reference voltage includes two operational comparators. These two reference voltages will be simultaneously input into the two operational comparators in positive and negative directions, that is, these two reference voltages will simultaneously perform speed increase comparison and speed decrease comparison through the two operational comparators. By adopting real-time dynamic frequency conversion tracking and signal acquisition, the running speed of the driving device can be increased or decreased freely, the signal can be instantaneously calibrated, and the running speed of the device can be accurately ensured to remain constant, enabling the vehicle to stably maintain a constant speed driving state. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is the system schematic diagram of the present invention.

[0019] Figure 2 is the circuit diagram of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] The present invention will be further described below in conjunction with specific embodiments and the accompanying drawings.

[0021] The present invention is a cruise control method and control system, which can be used in any means of transportation such as automobiles.

[0022] Combined with Figure 1 , Figure 2 As shown, the cruise control method of the present invention includes the following steps:

[0023] The first step: Collect the real-time speed signal of the driving device 1 during operation. After converting the collected real-time speed signal into a voltage signal and selecting and separating it through the signal selection and separation unit 4, the first reference voltage is obtained through the signal amplification unit 5 and the secondary filtering unit 9. The speed signal of the driving device 1 during operation includes: Hall signal (magnetic field induction signal), rotational speed signal (output rotational speed signal of the driving device such as an engine), frequency signal, PWM pulse signal, etc. Any one of the signals. The speed signal is filtered and converted into a voltage signal for subsequent processing.

[0024] Here, the driving device 1 refers to the power unit for driving means of transportation such as automobiles, including electric motors, gasoline engines, diesel engines, etc.

[0025] Step 2: The user sets the target speed voltage for constant-speed driving and inputs the feedback signal voltage for vehicle throttle control at the same time. After combining the target speed voltage and the feedback signal voltage, the second reference voltage is obtained.

[0026] Step 3: Input the first reference voltage and the second reference voltage into the signal comparison unit 6 for comparison. After comparison, a set of signals is generated and sent to the signal modulation unit 7.

[0027] Step 4: The comparison signal unit 6 outputs a control instruction signal to the modulation unit 7. The signal modulation unit 7 generates a feedback signal to the control unit 8 to make the control unit 8 perform operations of accelerating, decelerating, or driving at a constant speed.

[0028] In the above method, the signal comparison unit 6 includes a first operational comparator U20 and a second operational comparator U21. When the first reference voltage and the second reference voltage are compared, these two reference voltages will be input into the first operational comparator U20 and the second operational comparator U21 in positive and negative directions simultaneously, that is, these two reference voltages perform acceleration comparison and deceleration comparison through the first operational comparator U20 and the second operational comparator U21 at the same time.

[0029] In the above method, the merging method of the target speed voltage and the feedback signal voltage in the second step is as follows: The target speed voltage and the feedback signal voltage are connected in parallel. When the feedback signal voltage is lower than the target speed voltage, the target speed voltage will flow back into the lower feedback signal voltage, and the two voltages are combined and input into the signal comparison unit 6 as the second reference voltage; when the feedback signal voltage is higher than the target speed voltage, the feedback signal voltage will be input into the target speed voltage, and the two voltages are combined and input into the signal comparison unit 6 as the second reference voltage.

[0030] In the above method, in the first step, after the speed signal of the driving device 1 during operation passes through the signal conversion unit 3, the signal is filtered by the conversion unit 3, isolated by an optocoupler, and converted into a voltage signal and input into the signal selection and separation unit 4 for selection and separation.

[0031] Combined with the above control method, the cruise control system of the present invention is described in detail as follows.

[0032] Taking a new energy vehicle as an example of the present invention, the driving device 1 therein adopts a motor drive device, and the corresponding control unit 8 is used to control the operation of the motor. The present invention is connected to the in-vehicle computer of the vehicle through the first interface 21, and power, the required signals are input into the present invention through the first interface 21, and signals are output to the throttle controller for controlling the vehicle speed.

[0033] Specifically, the system includes: a signal acquisition unit 2 for acquiring real-time speed signals during the operation of the acquisition driving device 1, a signal conversion unit 3, a signal selection and separation unit 4, a signal amplification unit 5, a signal comparison unit 6, a signal modulation unit 7, a motor control unit 8, a secondary filtering unit 9, a target speed voltage input unit 10, and a power supply unit 11 for powering the circuit.

[0034] The signal acquisition unit 2 can be an external device or directly acquire relevant data in the vehicle on-board computer. After the signals during the operation of the driving device 1 are acquired by the signal acquisition unit 2, they are input into the signal conversion unit 3 through the first interface 21, and the signals are converted into voltage signals and input into the signal selection and separation unit 4; the signal amplification unit 5 includes an operational amplifier, and the real-time signals output by the signal selection and separation unit 4 are amplified by the operational amplifier and then filtered by the secondary filtering unit 9 and used as the first reference voltage and input into the signal comparison unit 6.

[0035] The signal acquisition unit 2 acquires real-time speed signals during the operation of the vehicle driven by the driving device 1, and these speed signals include: Hall signals, rotational speed signals, frequency signals, etc., one or a combination of signals. Through these signals, the actual real-time speed during the current vehicle driving process can be understood.

[0036] The signal conversion unit 3 includes: a first filtering circuit 31 composed of a capacitor C30 and a fuse B1, and an optocoupler U1.

[0037] The signal acquisition unit 2 inputs the acquired signals through the 11th pin of the first interface 21 of the system. After being filtered by the first filtering circuit 31 and through the isolation of the optocoupler U1, the signals are converted into voltage signals. These voltage signals enter the signal selection and separation unit 4, and the voltage signals are converted into voltage signals at a specific frequency.

[0038] The signal selection and separation unit 4 includes a frequency-voltage conversion chip 40 and a voltage regulator chip 41 for powering it. The frequency-voltage conversion chip 40 uses a frequency-voltage converter chip U2 of model LM2907N. The model of the voltage regulator chip is: 78M15G. The voltage signals converted by the signal selection and separation unit 4 enter the signal amplification unit 5, and the voltage signals are amplified by the signal amplification unit 5. In this embodiment, the signal amplification unit 5 uses a dual operational amplifier U7 with a signal of LM358. Of course, other amplifiers can also be used.

[0039] The voltage signal amplified by the signal amplification unit 5 enters the secondary filtering unit 9. After secondary filtering, a first reference voltage is obtained, and this first reference voltage signal enters the signal comparison unit 6. In the secondary filtering unit 9, filtering and signal stabilization are performed through a buck-boost power supply control chip U91 and a voltage stabilization circuit. The buck-boost power supply control chip U91 uses a model: XL6019 buck-boost power supply control chip, and a fixed-frequency oscillator and a frequency compensation circuit are provided inside it.

[0040] The reason for using the first filtering circuit 31 and the secondary filtering unit 9 is as follows: Conventional filtering cannot smoothly deliver the signals required by real-time varying quantities (such as real-time frequency conversion signals) to the comparator in the signal comparison unit 6 for synchronous comparison with the second reference voltage within the instant when the signal remains unchanged. The signal filtered by the first filtering circuit 31 for the first time of the first reference voltage is before the opto-isolation of the optocoupler U1. Through opto-isolation, the signal is prevented from overflowing, and the continuity during transmission is good and relatively stable. Thus, the on-off of the optocoupler is also output synchronously, which is beneficial for converting a signal with the same signal modulation unit 7 modulated and feedback signal voltage, and controlling the signal more accurately, more smoothly, and more conveniently. The second filtering is completed by the secondary filtering unit 9 after the above-mentioned opto-isolation, which better ensures that there is not much change in the signal before and after transmission, so that when the signal exchange time is very short, there is no excessive indirectness for too long, obtaining a more stable signal, enabling the signal to be sent for comparison in an orderly and cyclic manner while connecting the front and the back, and playing a role in suppressing signals that are too high or too low. That is, according to the signal before opto-isolation, a corresponding, real-time, and relatively stable signal is automatically modulated simultaneously, synchronously, and with the same frequency after opto-isolation as the controllable first reference voltage signal and input to the comparator of the signal comparison unit 6. After passing through the secondary filtering unit 9, the first reference voltage passes through the diode D300 and then enters the IN+ pin of the second operational comparator U21 through the resistor R43, and enters the IN- pin of the first operational comparator U20 through the resistor R35.

[0041] The target speed voltage input unit 10 is adjusted through the adjustable resistor R9 to set the user's cruise speed voltage signal, that is, the target speed voltage. At the same time, the feedback signal voltage of the vehicle throttle control input from the 3rd pin of the first interface 21, that is, the control voltage signal of the vehicle throttle at the current vehicle speed. The target speed voltage and the feedback signal voltage are combined and input to the signal comparison unit 6 as the second reference voltage for comparison with the first reference voltage.

[0042] When the two voltages in the second reference voltage (i.e., the target speed voltage and the feedback signal voltage) are in parallel, the change in the voltage difference is very small. When the feedback signal voltage is lower than the set target speed voltage, the set target speed voltage will backflow into the lower feedback signal voltage (the voltage feedback by the throttle controller is slightly lower). After the two voltages are combined, they are input to the comparison unit 6. That is, the second reference voltage is input to the IN- pin of the second operational comparator U21 through the resistor R41, and input to the IN+ pin of the first operational comparator U20 through the resistor R34.

[0043] The signal comparison unit 6 includes a first operational comparator U20 and a second operational comparator U21. The first reference voltage and the second reference voltage are simultaneously input to the first operational comparator U20 and the second operational comparator U21, and the input positions of the first reference voltage and the second reference voltage to the first operational comparator U20 and the second operational comparator U21 are opposite. That is, the first reference voltage and the second reference voltage are synchronously cross-compared through the first operational comparator U20 and the second operational comparator U21. In this embodiment, both the first operational comparator U20 and the second operational comparator U21 use a dual-channel operational amplifier of model LM358. Of course, a single operational amplifier with four channels or more channels can also be selected according to needs, so that multiple signals can participate in comparison and output control voltage simultaneously.

[0044] The motor control unit 8 includes two relays K0 and K1, and these two relays K0 and K1 are respectively connected to the signal modulation unit 7 through the speed increase feedback signal line A1 and the speed decrease feedback signal line A2.

[0045] When the user controls for constant speed cruise during real-time operation, the target rotation speed signal voltage (i.e., the voltage at the user's set cruise speed) can be reset at any time. The wider the set target rotation speed signal voltage, the higher the motor operating speed, and the more accurate the motor's constant speed operation will be. For example, if the set target rotation speed signal voltages are 1.0 V, 1.01 V, 1.001 V, 1.0001 V, 1.1 V, then the lowest value of the output constant speed accuracy is 1.1 V, and the highest value of the accuracy is 1.0001 V... and so on. The closer the value after the decimal point is to the set value, the more accurate it will be, which also depends on the accuracy of the comparator. The higher the comparator accuracy, the more accurate the constant speed. If the comparator accuracy is low, the constant speed error will be large, resulting in a large fluctuation amplitude of the collected actual speed signal voltage, a large change range of the linear voltage cut-off value and instability, and thus it is impossible to achieve a high constant speed accuracy. Expressed by the above example, the first signal voltage will jump between 1.0 V, 1.01 V, 1.001 V, 1.0001 V, 1.1 V

[0046] During the change, the voltage change from 1.0001 V to 1.0 V is very small, only a change of 1 / 10000 (micrometer level), while the voltage change from 1.1 V to 1.0 V is quite large, reaching a change of 1 / 10 (decimeter level). Therefore, a high-precision comparator should be selected for this invention, and the set target rotational speed signal voltage should be increased and broadened. The voltage of the motor control unit 8 should also be isolated, amplified, and adjusted to be close to the set target rotational speed signal voltage.

[0047] The working principle of the signal comparison unit 6 is as follows:

[0048] Combined with Figure 1 As shown, when the first reference voltage and the second reference voltage are compared through the signal comparison unit 6, the second reference voltage adopts a "circulating current" working process, while the first reference voltage is a "downstream" circulating working process. Signal instructions are generated by the first operational comparator U20 and the second operational comparator U21 in the signal comparison unit.

[0049] Simply put, if the output of U20 (value 1) is higher than the non-output of U21 (value 0), the output is 10, and the speed increase starts; if the non-output of U20 (value 0) is lower than the output of U21 (value 1), the output is 01, and the speed decrease starts; if the non-output of U20 (value 0) is equal to the non-output of U21 (value 0), the output is 00, and the constant speed cruise system stops working; if the output of U20 (value 1) is equal to the output of U21 (value 1), the increment table outputs 11, and the discharge starts. This comparison control is similar to a CPU processing and controlling the input and output of two groups of opposite "entangled signals".

[0050] The reason for this invention to adopt this comparison method is as follows: The first reference voltage is the vehicle's real-time speed signal collected, which determines the control range of the vehicle speed increase and decrease change. The set target speed voltage and the feedback signal voltage are combined as the second reference voltage. Without the set target speed voltage, the feedback signal voltage will be high and low, and the speed of the entire vehicle will also be fast and slow, which is not conducive to comparison. If only the set target speed voltage is used as the second reference voltage for comparison input, although it can also be compared with the first reference voltage to finally achieve a uniform speed, it cannot truly achieve a high-precision uniform speed effect. This invention combines the set target speed voltage and the feedback signal voltage as the second reference voltage. As long as the device power is sufficient and the motor does not slip during operation, even in a very harsh working environment, this uniform speed system will overcome and break through any resistance encountered during the device's working process, enabling the motor to still reach a uniform working state.

[0051] The target speed voltage is set by converting the maximum speed of the motor at a certain ratio. Thus, the highest working efficiency of the motor running at a constant speed can be modulated, the maximum torque can be output by the motor at a constant speed in a short time, the motor can output the limit power at any set constant speed, and the motor power can be maximally amplified in a short time, etc.

[0052] The first reference voltage and the second reference voltage are input into the first operational comparator U20 and the second operational comparator U21 in the signal comparison unit 6. Since the first reference voltage and the second reference voltage are synchronously cross-compared by the first operational comparator U20 and the second operational comparator U21, where the first operational comparator U20 serves as an acceleration comparison circuit and the second operational comparator U21 serves as a deceleration comparison circuit. When the first reference voltage and the second reference voltage are compared, the two comparison voltages enter "deceleration comparison" and "acceleration comparison" simultaneously, and there is no time difference during the comparison, so that the highest comparison speed and signal exchange speed can be achieved.

[0053] The signal modulation unit 7 includes two parallel optocouplers U5 and U6, and these two optocouplers U5 and U6 respectively form an acceleration module and a deceleration module. The two optocouplers U5 and U6 are respectively connected to the first operational comparator U20 and the second operational comparator U21 in the signal comparison unit 6. The signal voltage is amplified through the output pins of the first operational comparator U20 and the second operational comparator U21 and then connected to the optocouplers U5 and U6 in the signal modulation unit 7 through the output terminals respectively. In the signal modulation unit 7, the signal voltage is stored in the capacitors C20 and C21, and is charged and discharged according to the comparison control.

[0054] In the signal comparison unit 6 and the signal modulation unit 7, the set dual-signal synchronous grouping comparison mode (i.e., acceleration comparison and deceleration comparison) and the command control mode of the acceleration module and the deceleration module optocouplers U5 and U6 corresponding to the amplified output voltages of each are in a parallel execution command control mode, with opposite control functions.

[0055] During operation, the present invention simultaneously turns on optocoupler U5 and turns off optocoupler U6, and conveys the voltages stored in capacitors C20 and C21 to pins 1-3 of relay K0 of control unit 8, then to pins 3-1 of relay K1, and then to the throttle control of drive device 1. During charging, the throttle voltage is connected to optocoupler U5 through relay K1 of control unit 8. When the 7th pin of U20 outputs a high voltage to U5, U5 operates, and the throttle output voltage will be conveyed to pins 4-3 of optocoupler U5 through pins 4-6 of relay K1. After pins 4-3 are turned on, the throttle voltage is conveyed to capacitors U20 and U21 for storage. Through cyclic control, the throttle voltage is made to be consistent with the set target speed signal voltage. When the throttle voltage is lower than the set target speed signal voltage, pins 1-3 of relay K0 of control unit 8 are conveyed to pins 3-1 of relay K1, and then to the throttle voltage, increasing the throttle voltage to achieve the purpose of speed increase; when the

[0056] throttle voltage is higher than the set target speed signal voltage, the comparator U21 of comparison signal unit 6 outputs a control voltage at its 7th pin to drive optocoupler U6 to operate. The throttle voltage stored in capacitors U20 and U21 is conveyed to the ground wire through the conduction of pins 4-3 of U6, and discharges until the first input voltage is lower than the set target speed signal voltage (the second reference voltage). The 7th pin of comparator U21 is turned off, stopping the output voltage, and U21 enters the standby state. Through comparison signal unit 6, a control instruction signal is output to modulation unit 7 and control unit 8 to perform operations of speed increase, speed decrease, and constant speed.

[0057] The specific working process of comparison is as follows:

[0058] When the first reference voltage is lower than the second reference voltage, that is, when the voltage at resistor R43 is lower than the voltage at resistor R41, the second operational comparator U21 in the deceleration comparison circuit does not work. At this time, the optocoupler U6 in the deceleration module does not work, and capacitors C20 and C21 will not discharge through U6. While the first reference voltage is lower than the second reference voltage, in the acceleration comparison circuit composed of the first operational comparator U20, the input positions of the first reference voltage and the second reference voltage are exchanged relative to the input positions of the deceleration comparison circuit. At this time, the second reference voltage is higher than the first reference voltage, that is, the voltage at resistor R34 is higher than the voltage at resistor R35. At this time, the first operational comparator U20 in the acceleration comparison circuit works, and the optocoupler U5 of the connected acceleration module starts to work. The throttle voltage of the vehicle is input to the motor control unit 8 through the 9th pin of the first interface 21, controlling the conduction of the 1-2 pins of the relay K1. Then, it is divided by resistors R621 and R62 to drive the triode Q6 to work. At this time, the voltage of the 4th pin of the optocoupler U51 is obtained from the regulated power supply R55 in the power supply unit 11. After the optocoupler U51 conducts, the voltage is delivered to the relay KO, and the relay K0 starts to work. The 1-3 pins of the relay K0 conduct, and the voltages of capacitors C20 and C21 are delivered to the 3rd pin of K1 through the acceleration feedback signal line A1 via the 1-3 pins of K0, and the relay K1 works. That is, the 1-3 pins and 4-6 pins of the relay K1 conduct, and the throttle input voltage sequentially passes through the 9th pin of the first interface 21, the 1-3 pins of the relay K1, and the 3-1 pins of the relay K0 and is connected to the acceleration feedback signal line A1. Because the motor speed is low and the throttle needs to be increased (at this time the throttle voltage is also low), when increasing the throttle, the throttle voltage of the 10th pin of the first interface 21 increases and is delivered to the resistor R62 (for controlling the valve voltage of the triode Q6 drive). As long as the voltage reaches 0.65 volts, the optocoupler U51 conducts, and the relay K0 works. Thus, the electric quantity accumulated by capacitors C20 and C21 is sent to the 1-3 pins of the relay K0 through the acceleration feedback signal line A1, input to the 9th pin of the first interface 21 through the 1-3 pins of the relay K1, and then delivered to the throttle control to realize the motor acceleration process. At the same time, because the relay K1 works, the throttle voltage will pass through the 10th pin of the first interface 21, the 4-6 pins of the relay K1, and then be delivered to the optocoupler U5 through the deceleration feedback signal line A2. When U20 works, U5 conducts, and the throttle voltage is continuously delivered to C20 and C21 for storage in a modulated acceleration manner to complete the acceleration process.

[0059] A second interface P5 is set in the motor control unit 8. This second interface P5 is a switch connecting constant speed and stepless variable constant speed. When the motor is to work at a constant speed, the necessary input of the second interface P5 conducts.

[0060] The 6th pin of the first interface 21 is the power supply voltage of the system. One path passes through the diode D1 to supply power to the signal conversion unit 3, the signal selection and separation unit 4, and the signal amplification unit 5. The second path passes through the diode D30 to supply power to the power supply unit 11. The third path is directly connected to the second interface P5 to supply power to the relay K1. The fourth path is directly connected to the third interface P2 to provide driving power for the speed display LED or the LCD.

[0061] When the first reference voltage is higher than the second reference voltage, the first operational comparator U20 in the speed increase comparison circuit does not work, and the optocoupler U5 in the speed increase module does not work. That is, at this time, the voltage at resistor R35 is higher than the voltage at R34, while the second operational comparator U21 in the deceleration comparison circuit works, and the optocoupler U6 in the deceleration module works. That is, the voltage at resistor R43 is higher than the voltage at resistor R41, and capacitors C20 and C21 are discharged to the ground wire through the optocoupler U6. While the first reference voltage is higher than the second reference voltage, the throttle input voltage is transmitted to the ground wire through pins 1-2 of relay K0. This is to attenuate and modulate the voltages of capacitors C20 and C21 to decelerate. Because the throttle voltage decreases due to discharging at this time, the throttle voltage output from pin 10 of the first interface 21 is transmitted to pin 2 of relay K1. Since relay K1 works, its pin 2 is floating. The other path is reduced again through resistor R62 and then transmitted to transistor Q6. At this time, the threshold voltage of transistor Q6 is too low to drive, so transistor Q6 does not work, and optocoupler U51 does not work either. Relay KO does not work, and pins 1-2 of relay KO are conducting. The voltages of capacitors C20 and C21 pass through the speed increase feedback signal line A1, and then through pins 1-2 of relay K0 to be transmitted to the ground wire (if the throttle does not continue to increase the voltage, it is default that the system stops working, and capacitors C20 and C21 discharge automatically). At the same time, relay K1 works, and its pins 1-3 and 4-6 are conducting. The throttle input voltage passes through pin 9 of the first interface 21 and pins 1-3 of relay K1. Relay K0 does not work, and pin 3 of relay K0 is floating. The voltages of C20 and C21 are connected to the speed increase feedback signal line A1 of relay K0 until pins 1-3 are disconnected. Also, because pins 4-6 of relay K1 are conducting, and the motor speed decreases while discharging, the throttle voltage passes through pin 10 of the first interface 21, through fuse B3, and is transmitted to pins 4-6 of relay K1, and is transmitted to optocoupler U5 through the deceleration feedback signal A2, waiting for the throttle voltage input. At the same time, the first reference voltage in the speed increase comparison circuit U20 is low, and the second reference voltage is high. Thus, optocoupler U5 works, and the throttle voltage will pass through pins 4-6 of relay K1, and then through the deceleration feedback signal line A2 to be transmitted to optocoupler U5. At this time, optocoupler U5 is working, and the throttle voltage will be input to capacitors C20 and C21 for acceleration. The electric charges accumulated in capacitors C20 and C21 will be transmitted to pin 1 of relay K0 through the speed increase feedback signal line A1, waiting for the throttle to increase. However, at this time, pin 10 of the first interface 21 is at a low voltage, and transistor Q6, optocoupler U51, and relay K0 do not work. Therefore, pins 1-2 of relay K0 are conducting, and the voltage is transmitted to the ground wire.Since the relay K0 is not working, the pins 1-3 of K0 have not been conducting before the voltage charge and discharge cycle, and cannot provide high voltage to the pins 3-1 of the relay K1. The input voltage to the throttle (i.e., pin 9 of the first interface 21) also has no voltage, forcing the throttle voltage to increase the voltage through pin 10 of the first interface 21. Since pins 3 and 10 of the first interface 21 are in parallel, that is, pin 3 of the first interface 21 is the "signal voltage for real-time comparison and feedback with the target speed voltage" to which the throttle voltage is connected. After its "set target speed signal input" voltage is combined, when the set target speed signal input voltage is higher than the feedback signal voltage, it will cause backflow, increasing the throttle voltage. Consequently, the voltage at pin 10 of the first interface 21 of the connector increases and is transmitted to the resistor R62. When the voltage at the resistor R62 reaches the threshold drive voltage of the triode Q6, which is 0.65V - 0.8V, the triode Q6, optocoupler U51, and relay K0 start to work. The voltages in the capacitors C20 and C21 are transmitted to the pins 1-3 of the relay K0 through the speed increase feedback signal line A1 (at this time, K0 is working), and then from pin 3 of the relay K0, through the pins 3-1 of the relay K1, to pin 9 of the first interface 21 of the connector and input to the throttle, realizing the acceleration process of the motor, and continuously controlling in a cycle until the system stops working.

[0062] Certainly, the above are only specific embodiments of the present invention and do not limit the scope of implementation of the present invention. Any equivalent changes or modifications made according to the structure, characteristics, and principles described in the scope of the patent application of the present invention should be included within the scope of the patent application of the present invention.

Claims

1. A constant speed cruise control method, characterized in that: The method comprises the following steps: The first step is to collect the real-time speed signal of the driving device (1) during operation, convert the collected real-time speed signal into a voltage signal, select and separate the signal after passing through a signal selection and separation unit (4), and then obtain a first reference voltage through a signal amplification unit (5) and a secondary filtering unit (9); Step 2: The user sets the target speed voltage required for uniform speed driving, and inputs the feedback signal voltage of the vehicle throttle control at the same time, and combines the target speed voltage and the feedback signal voltage to obtain the second reference voltage; Step 3: Input the first reference voltage and the second reference voltage to the signal comparison unit (6) for comparison, and generate a signal to the signal modulation unit (7) after comparison; Step 4: the signal modulation unit (7) generates a feedback signal to the control unit (8), and the control unit (8) increases, decreases, or makes the driving device (1) of the vehicle speed up or speed down; The signal comparison unit (6) comprises a first operational comparator (U20) and a second operational comparator (U21). When the first reference voltage and the second reference voltage are compared, the two reference voltages are simultaneously input into the first operational comparator (U20) and the second operational comparator (U21) in a positive and negative alternating manner, that is, the two reference voltages are simultaneously compared for speed-up and speed-down through the first operational comparator (U20) and the second operational comparator (U21). In the second step, the target speed voltage and the feedback signal voltage are combined in the following manner: the target speed voltage and the feedback signal voltage are connected in parallel; when the feedback signal voltage is lower than the target speed voltage, the target speed voltage is reversely fed into the lower feedback signal voltage, and the two voltages are combined and input into the signal comparison unit (6) as the second reference voltage; when the feedback signal voltage is higher than the target speed voltage, the feedback signal voltage is input into the target speed voltage, and the two voltages are combined and input into the signal comparison unit (6) as the second reference voltage; During the operation of the driving device (1), the speed signal passes through a signal conversion unit (3), the signal is filtered by the signal conversion unit (3), and then converted into a voltage signal through optical coupling isolation and input into a signal selection and separation unit (4) having a frequency-voltage conversion circuit for selection and separation; When the first reference voltage is compared with the second reference voltage by the signal comparison unit (6), a signal instruction is generated by the first operational comparator (U20) and the second operational comparator (U21) in the signal comparison unit. If the first operational comparator (U20) has an output and the second operational comparator (U21) has no output, the speed increase starts; If the first operational comparator (U20) has no output and the second operational comparator (U21) has an output, deceleration begins; If the first operational comparator (U20) has no output and the second operational comparator (U21) has no output, the cruise control system stops working; If the first operational comparator (U20) has an output and the second operational comparator (U21) has an output, the cruise control system starts to work.

2. The constant speed cruise control method according to claim 1, characterized in that: In the first step, the real-time speed signal of the driving device (1) during operation includes: any one of a Hall signal, a rotation speed signal, a frequency signal, and a PWM pulse signal, or a combination of these signals.

3. A constant speed cruise control system, characterized in that: The system comprises: a signal acquisition unit (2) for acquiring a real-time speed signal of a driving device (1) during operation, a signal conversion unit (3), a signal selection and separation unit (4), a signal amplification unit (5), a signal comparison unit (6), a signal modulation unit (7), a motor control unit (8), a secondary filtering unit (9), a target speed voltage input unit (10), and a power supply unit (11); The signal acquisition unit (2) acquires the signal during the operation of the driving device (1) and inputs the acquired signal into the signal conversion unit (3) through the first interface (21), converts the signal into a voltage signal and inputs the voltage signal into the signal selection and separation unit (4); The signal amplification unit (5) comprises an operational amplifier, and the real-time signal output by the signal selection and separation unit (4) is amplified by the operational amplifier and filtered by the secondary filtering unit (9) before being input as a first reference voltage to the signal comparison unit (6); The target speed voltage input unit (10) is connected in parallel with the feedback signal voltage of the vehicle throttle control inputted by the first interface (21) and then inputted into the signal comparison unit (6) as a second reference voltage; The signal comparison unit (6) comprises a first operational comparator (U20) and a second operational comparator (U21), the first reference voltage and the second reference voltage are simultaneously and alternately input into the first operational comparator (U20) and the second operational comparator (U21), and the positions of the input signals of the first reference voltage and the second reference voltage input into the first operational comparator (U20) and the second operational comparator (U21) are opposite to those of the reference signals; The signal modulation unit (7) comprises two parallel optical couplers (U5, U6), the two optical couplers (U5, U6) are respectively connected to the two operational comparators (U20, U21) in the signal comparison unit (6), and the signal voltage is amplified through the output pins of the two operational comparators (U20, U21) and connected to the optical couplers (U5, U6) in the signal modulation unit (7) through the output ends; The motor control unit (8) comprises two relays (K0, K1), and the two relays (K0, K1) are connected to the signal modulation unit (7) via a speed-increasing feedback signal line and a speed-decreasing feedback signal line respectively; The signal conversion unit (3) comprises: a first filtering circuit (31) connected to the first interface (21), and an optical coupler connected to the first filtering circuit (31); after the speed signal collected by the signal collection unit (2) is filtered by the first filtering circuit (31), the optical coupler is used to perform optical coupling isolation, and the speed signal is converted into a voltage signal and input into the signal selection and separation unit (4) for selection and separation; The signal selection and separation unit (4) comprises a frequency-voltage conversion chip (40) and a voltage stabilization chip (41) for supplying power to the frequency-voltage conversion chip (40); In the secondary filtering unit (9), filtering and signal stabilization are performed through a buck-boost power supply control chip (U91) and a voltage stabilizing circuit; The signal modulation unit (7) includes capacitors (C20, C21) for storing signal voltage.

4. The cruise control system according to claim 3, characterized in that: The speed signals during the operation of the signal acquisition unit (2) include: Hall signal, rotational speed signal, frequency signal, PWM pulse signal, or a combined signal.

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