TWI703808B - Electric motor controlling system and vibration restraining method for using the same - Google Patents

Abstract

An electric motor controlling system used for restraining vibration of an electrical vehicle is disclosed. The controlling system includes a PID-controller and a vibration restraining compensator. The PID-controller generates a basic torque command through performing a calculation on input speed-error signal of the electrical vehicle, the vibration restraining compensator generates a compensated torque command through performing a compensation-gain procedure on the input speed-error signal. The vibration restraining compensator further receives a motor speed of the electrical vehicle, sets its output as the compensated torque command when the motor speed is smaller than a pre-set active speed level, otherwise sets the output as 0. The controlling system generates an output torque command via adding up the basic torque command and the output of the vibration restraining compensator, and controls the operation of electrical-components of the electrical vehicle through the output torque command.

Description

Motor control system and its vibration suppression method

The invention relates to a control system, in particular to a motor control system, and a vibration suppression method adopted by the motor control system.

In recent years, the electronic appliances that have been electrified on a large scale and are most accepted by the market should be industrial vehicles, such as stackers and unmanned vehicles. Since most of the application environments of industrial vehicles are indoor spaces such as workshops and warehouses, such environments should not contain exhaust gases that are harmful to the human body. Therefore, compared with vehicles for civilian use, electric industrial vehicles are more marketable. Place accepted.

Although the existing industrial vehicles still have basic requirements for maneuverability and ride feeling, the transmission mechanism and suspension system of industrial vehicles are usually simpler than civilian vehicles due to cost considerations. Therefore, how to make up for the inherent deficiencies of the industrial vehicle structure through control technology has become a major issue for manufacturers when developing industrial vehicles.

The control modes of electric vehicles can generally be divided into two architectures: torque control mode and speed control mode. Torque control mode is common in electric vehicles, electric vehicles and other civilian vehicles. The electric vehicle in torque control mode directly converts the throttle signal into a torque command, so the driver can directly adjust the motor output torque by adjusting the throttle state, and then control the electric vehicle to the target speed and target position.

In contrast, industrial vehicles require a relatively stable speed, and even some electric vehicles (such as stackers) need to have their own deceleration and braking force when the accelerator is released. Therefore, most industrial vehicles will be at speed. Control mode to run.

Refer to FIG. 1A, which is a block diagram of the electric vehicle in speed control mode. As shown in Fig. 1A, an electric vehicle generally operating in a speed control mode will have at least one PID controller 11. The PID controller 11 receives the input speed error signal 12 of the electric vehicle, and generates a corresponding signal after calculation. The torque command 13. In this way, the electric vehicle can control the rear motor components (such as a traction motor, not shown in the figure) through the torque command 13. The PID controller 11 is mainly used to follow the speed command issued by the driver. It obtains the deviation between the throttle signal given by the driver and the actual output value (for example, the actual motor speed), and performs processing based on the deviation Linear operation is used to generate the corresponding control quantity, and then the operation of the motor components is controlled according to this control quantity.

However, generally using the speed control mode of the PID controller 11 cannot overcome the vibration problem caused by the mechanical characteristics of the transmission mechanism (such as gearbox, steering differential, etc.) when the electric vehicle is running, which will cause the driver to control The effect and ride feel are not good.

As shown in Fig. 1B, it is a schematic diagram of the non-linear dead zone of the gear. As shown in Figure 1B, the joint of the gear 2 will have a backlash distance W, so when the driver changes the input direction, the initial input change will not affect the output immediately, but need to wait for the gear 2 on the input side to move The backlash distance W enables the subsequent input change to actually affect the output when the gear 2 is re-engaged. Therefore, when the input direction changes or the gear 2 is initially in a non-engaged state, a non-linear dead zone (dead zone) will be generated in the system model, and the driver’s input cannot affect the electric load in this dead zone. The output of the tool.

As mentioned above, the current linear controller (such as the PID controller 11 in FIG. 1A) cannot effectively deal with the above-mentioned nonlinear characteristics of the transmission mechanism (such as the gear 2 in FIG. 1B). Therefore, the electric vehicle encounters the above-mentioned nonlinear characteristics. In the dead zone, there will be poor response or abnormal torsion, vibration, etc. (for example, the traction motor will vibrate in certain operating areas to reduce the comfort of the car), which will cause poor working conditions.

The main purpose of the present invention is to provide a motor control system and a vibration suppression method for electric vehicles, which can suppress abnormal torsion and vibration caused by the transmission mechanism of the electric vehicles.

In order to achieve the above object, the motor control system of the present invention is mainly applied to an electric vehicle, and includes: a PID controller, receiving an input speed error signal of the electric vehicle, and calculating the input speed error signal Generate a basic torque command; and a vibration suppression compensator, set in parallel with the PID controller, receive the input speed error signal and a motor speed of the electric vehicle, and perform a compensation gain on the input speed error signal to generate a Compensation torque command.

Wherein, the vibration suppression compensator sets an output value to 0 when judging that the motor speed is not less than the preset consistent energy level, and sets the output value as the compensation torque when judging that the motor speed is less than the enable level command. The motor control system adds the basic torque command and the output of the vibration suppression compensator to generate an output torque command, and controls the operation of a motor component of the electric vehicle according to the output torque command.

In order to achieve the above object, the vibration suppression method of the motor control system of the present invention is applied to a motor control system in an electric vehicle, and includes the following steps:

Step a): A PID controller in the motor control system receives an input speed error signal of the electric vehicle;

Step b): The PID controller calculates the input speed error signal to generate a basic torque command;

Step c): Receive the input speed error signal and a motor speed of the electric vehicle by a vibration suppression compensator in the motor control system;

Step d): The input speed error signal is compensated by the vibration suppression compensator to generate a compensation torque command;

Step e): The vibration suppression compensator sets an output value to 0 when judging that the motor rotation speed is not less than the preset consistent energy level, and sets the output value to the value when judging that the motor rotation speed is less than the enable level Compensation torque command;

Step f): The motor control system adds the basic torque command and the output of the vibration suppression compensator to generate an output torque command;

Step g): The motor control system transmits the output torque command to a motor component of the electric vehicle to control the operation of the motor component; and

Step h): The motor control system continuously judges whether the electric vehicle is closed, and continues to execute the steps a) to g) before the electric vehicle is closed.

Compared with the related technology, the technical effect of the present invention is that the vibration suppression compensator can suppress abnormal torsion and vibration caused by the nonlinear characteristics of the transmission mechanism during the operation of the electric vehicle, thereby improving the overall electric load. With great ride comfort.

Moreover, as long as the parameters used by the vibration suppression compensator are appropriately adjusted, such as individually setting the enable level, gain value, or bandwidth used by the low-pass/high-pass filter, the present invention can be applied to various types of electric motors. The vehicle can achieve the expected vibration suppression effect, so it is more flexible and convenient to use.

For a preferred embodiment of the present invention, with the drawings, the detailed description is as follows.

First, please refer to FIG. 2, which is a block diagram of the motor control system of the present invention. Fig. 2 specifically discloses the motor control system 3 of the present invention, which is mainly applied to electric vehicles. Specifically, the motor control system 3 of the present invention is mainly applied to industrial electric vehicles operating in a speed control mode, such as stackers, conveyors, etc., but is not limited.

As shown in FIG. 2, the motor control system 3 of the present invention mainly has a Proportional-Integral-Derivative (PID) controller 31 and a vibration suppression compensator 32. In the present invention, the PID controller 31 is used to follow a speed command issued by the driver of the electric vehicle (that is, a signal corresponding to the rotation amplitude of the throttle operation), and the vibration suppression compensator 32 is used to meet the conditions When the time, a torque command output by the PID controller 31 is compensated to suppress the non-linear characteristics of the internal transmission components (such as gearbox, steering differential, etc. or a combination) of the electric vehicle during operation. Normal torsion and vibration.

In one embodiment, the PID controller 31 and the vibration suppression compensator 32 are implemented by different hardware components, and are electrically connected in parallel with each other. In another embodiment, the PID controller 31 and the vibration suppression compensator 32 can be firmware, and can be executed by the same or different processors to achieve corresponding functions, but is not limited.

The PID controller 31 is mainly composed of a proportional unit (Proportional Unit), an integral unit (Integral Unit) and a derivative unit (Derivative Unit). The designer of the PID controller 31 can set the proportional unit gain Kp and integral unit respectively. The unit gain Ki and the differential unit gain Kd are used to adjust the characteristics of the PID controller 31, thereby making the PID controller 31 suitable for a system that is basically linear and whose dynamic characteristics do not change with time. Specifically, the PID controller 31 is usually used as a feedback loop element, which compares the output data with a reference value, and then calculates a new input value based on the difference obtained after the comparison. By using the new input value, the output data of the system can be reached or maintained at the reference value, thereby making the entire system more stable.

Generally speaking, the proportional unit, integral unit and differential unit of the PID controller 31 correspond to the current error, past cumulative error and future error respectively. Therefore, if any of the units does not need to be used, just change the parameters of the unused units Just set it to zero. In an embodiment of the present invention, the motor control system 3 can be implemented without using a differential unit in the PID controller 31 (that is, the parameter of the differential unit in the PID controller 31 is set to zero), and The PID controller 31 can be converted into a PI controller, but not limited to this.

As shown in FIG. 2, the PID controller 31 mainly receives an input speed error signal 43 of the electric vehicle, and then calculates the input speed error signal 43 to generate a corresponding basic torque command 44. In the present invention, when there is no abnormal torsion or vibration of the electric vehicle, the motor control system 3 directly uses the basic torque command 44 generated by the PID controller 31 as the final output torque command 46, that is, The basic torque command 44 is not compensated, or it is deemed that the basic torque command 44 is compensated but the compensation value is 0.

It is worth mentioning that in one embodiment, the electric vehicle has a throttle unit (not shown) for the driver to operate to generate a corresponding speed signal 41, and a throttle unit (not shown) for detecting the rotation of the corresponding speed signal 41 A sensor (not shown in the figure) of a motor component 5 (such as a motor) and a motor speed 42. In this embodiment, the motor control system 3 mainly receives the speed signal 41 generated based on the driver's operation from the throttle unit, and receives the actual motor speed 42 from the sensor, and combines the speed signal 41 with the motor speed 42 Subtract to obtain the input speed error signal 43. In the present invention, the motor control system 3 uses the input speed error signal 43 as an input signal of the PID controller 31, that is, the motor control system 3 mainly operates in a speed control mode.

The vibration suppression compensator 32 is mainly arranged in parallel with the PID controller 31 and electrically connected, that is, it shares an input port and an output port with the PID controller 31. In the present invention, the vibration suppression compensator 32 can receive the speed error signal 43 and execute a compensation gain program on the input speed error signal 43 to generate a compensation torque command 45. In the present invention, when the electric vehicle has abnormal torsion or vibration, the motor control system 3 will combine the basic torque command 44 generated by the PID controller 31 with the compensation torque generated by the vibration suppression compensator 32 The command 45 is added together to be the final output torque command 46, that is, the basic torque command 44 is compensated by the compensation torque command 45. In this way, the compensation torque command 45 in the output torque command 46 is used to eliminate the abnormal torsion and vibration caused by the nonlinear characteristics of the transmission member during the operation of the electric vehicle.

Specifically, after the motor control system 3 of the present invention is installed on any electric vehicle, the driver can conduct a ride test on the electric vehicle, thereby obtaining the abnormal torsion and vibration phenomena when the electric vehicle is running. A specific speed or a range of speeds, as detailed later.

In one embodiment, the driver can set an enabling level (for example, the enabling level 6 shown in FIGS. 3 and 4) to the motor control system 3 after the test is completed, that is, setting the enabling level 6 It is a specific speed or a speed range at which abnormal torsion and vibration occurs when the electric vehicle tested above is running. When the electric vehicle is running, the vibration suppression compensator 32 continuously receives the motor speed 42 from the sensor, and determines whether the motor speed 42 is less than the preset enable level 6. When the motor speed 42 is less than the preset enable level 6, it means that the electric vehicle is about to appear or has abnormal torsion and vibration, that is, the gear of the transmission mechanism in the electric vehicle (not shown) is about to enter or Has entered a dead zone that will produce nonlinear characteristics.

In order to solve the above-mentioned problem, the vibration suppression compensator 32 of the present invention will set an output produced by it as the generated compensation torque command 45 when judging that the motor speed 42 is less than the enable level 6. At this time, the value of the output torque command 46 of the motor control system 3 is equal to the calculated sum of the basic torque command 44 and the compensation torque command 45. In other words, the motor control system 3 of the present invention compensates for the value of the torque command 45 to suppress abnormal torsion and vibration caused by the gears of the transmission mechanism in the electric vehicle entering the dead zone.

In addition, when the vibration suppression compensator 32 determines that the motor speed 42 is not less than the enable level 6, that is, when it is greater than or equal to the enable level 6, it will directly set its output to zero. At this time, even if the motor control system 3 generates the output torque command 46 based on the calculated sum of the basic torque command 44 and the output of the vibration suppression compensator 32, the value of the output torque command 46 will still be the same at this time. Equal to the value of base torque command 44. In other words, when the motor speed 42 is not less than the enabling level 6, the gears representing the transmission mechanism in the electric vehicle have not yet entered the dead zone, and the electric vehicle has not yet experienced the abnormal torsion and vibration phenomenon, so there is no It is necessary to compensate the basic torque command 44, that is, no compensation is performed at this time.

In one embodiment, the vibration suppression compensator 32 can execute the compensation gain program on the input speed error signal 43 and generate the compensation torque command 45 only when it determines that the motor speed 42 is less than the enable level 6, and then determines the motor When the speed 42 is not less than the enable level 6, the compensation gain program is not executed and the output is directly set to 0. In this way, system performance can be effectively saved.

In another embodiment, the vibration suppression compensator 32 can continue to execute the compensation gain program on the input speed error signal 43 and continue to generate the compensation torque command 45, but only output when the motor speed 42 is less than the enable level 6 The generated compensation torque command 45. In this way, the compensation efficiency of the system can be effectively improved.

In the present invention, the motor control system 3 adds the basic torque command 44 of the PID controller 31 and the output of the vibration suppression compensator 32 (ie, 0 or compensation torque command 45) to generate the final output torque The command 46 is used to control the operation of the motor member 5 behind the electric vehicle according to the output torque command 46. In this embodiment, the motor component 5 is electrically connected to the motor control system 3, but it is not limited.

Please continue to refer to FIG. 3, which is a first specific embodiment of the block diagram of the vibration suppression compensator of the present invention. In the embodiment of FIG. 3, the vibration suppression compensator 32 can be mainly implemented in hardware or software or a mixed configuration, and is divided into multiple parts according to the functions performed, including a low-pass filter 321 and a processor 322, a gainer 323 and a comparator 324.

The low-pass filter 321 receives the input speed error signal 43 and performs filtering processing on the input speed error signal 43 to extract a low frequency part of the input speed error signal 43. The processor 322 receives the input speed error signal 43, and the low-pass filter 321 receives the low-frequency part of the input speed error signal 43, and then subtracts the input speed error signal 43 from the low-frequency part of the signal, thereby extracting the input speed The high frequency part 431 of the error signal 43 is a signal. In the present invention, the driver can set the bandwidth used by the low-pass filter 321 by himself, thereby ensuring that the signal calculated by the processor 322 retains the high frequency part 431 of the input speed error signal 43.

The gainer 323 receives the high frequency part 431 of the signal generated by the processor 322 and compensates the high frequency part 431 of the signal to generate the compensation torque command 45.

Specifically, the present invention first filters out the low-frequency part of the input speed error signal 43, and only performs compensation gain on the high-frequency part 431 of the input speed error signal 43, thereby making the generated compensation torque command 45 more direct. The ground reflects the received input speed error signal 43. It is worth mentioning that for different electric vehicles, the corresponding relationship between the input speed error signal 43 and the final output torque command 46 will also be different. Therefore, the present invention allows the driver to set a gain value used by the gain 323 in the vibration suppression compensator 32 by himself, so that the motor control system 3 of the present invention can be easily applied to various types of electric vehicles.

Moreover, the vibration suppression compensator 32 in this embodiment may further receive the motor speed 42 of the electric vehicle and the enable level 6 through the comparator 324, and compare the motor speed 42 with the enable level 6 to It is determined whether the output of the vibration suppression compensator 32 is to be set to 0 or to the generated compensation torque command 45.

As mentioned above, different electric loads have different transmission system configurations, which will cause the gears to enter the dead zone and cause abnormal torsion or vibration in the speed or speed range. Therefore, the present invention allows the driver to set the enable level 6 used by the comparator 324 in the vibration suppression compensator 32 (that is, the specific speed or speed range set by himself), thereby enabling the motor control system of the present invention 3 It can be easily applied to various types of electric vehicles.

In one embodiment, the vibration suppression compensator 32 mainly sets the output when the motor speed 42 is not less than the enable level 6 (that is, the speed of the electric vehicle is not lower than the speed at which abnormal torsion or vibration occurs) When the motor speed 42 is less than the enable level 6 (ie, the speed of the electric vehicle is lower than the speed at which abnormal torsion or vibration may occur), the output is set as the compensation torque command 45. In other words, when the motor speed 42 is not less than the enable level 6, that is, greater than or equal to the enable level 6, the content of the output torque command 46 of the motor control system 3 is the calculation of the basic torque command 44 and 0 The sum, that is, it is simply the basic torque command 44, and no compensation is made at this time; and when the motor speed 42 is less than the enable level 6, the value of the output torque command 46 of the motor control system 3 is the basic torque command 44 and Compensation torque command 45 is the calculated sum.

As mentioned above, the vibration suppression compensator 32 of the present invention mainly compensates and gains the high frequency part of the input speed error signal 43. In other embodiments, the vibration suppression compensator 32 can also directly filter the input speed error signal 43 through a high-pass filter.

Refer to FIG. 4, which is a second specific embodiment of the block diagram of the vibration suppression compensator of the present invention. The vibration suppression compensator 32' in the embodiment of FIG. 4 can be implemented by hardware or software or a hybrid configuration, and is divided into multiple parts according to the functions performed, including a high-pass filter 325, a gainer 323 and A comparator 324.

In this embodiment, the vibration suppression compensator 32' receives the input speed error signal 43 through the high-pass filter 325, and filters the input speed error signal 43 to directly extract a signal high frequency part 431 of the input speed error signal 43. Compared with the embodiment of FIG. 3, the vibration suppression compensator 32' of the embodiment shown in FIG. 4 does not need to be additionally provided with a processor 322, and the foregoing embodiment can be omitted to subtract the input speed error signal 43 from the low frequency part of the signal. Therefore, the processing efficiency can be effectively improved.

In the present invention, the driver can set the bandwidth used by the high-pass filter 325 by himself, so as to ensure that the signal processed by the high-pass filter 325 retains the high frequency part 431 of the input speed error signal 43.

It is worth mentioning that the vibration suppression compensator 32 in Figure 3 first extracts the low-frequency part of the input speed error signal 43, and then deletes the low-frequency part of the signal from the original input speed error signal 43 to obtain the high-frequency part of the signal. 431, therefore, the noise of the high-frequency part 431 of the obtained signal is relatively less than the noise of the high-frequency part 431 of the signal obtained by the vibration suppression compensator 32' of FIG. 4 directly through the high-pass filter 325.

Similar to the embodiment shown in FIG. 3, the gainer 323 in FIG. 4 and the described embodiment receives the high-frequency part 431 of the signal generated after filtering by the high-pass filter 325, and compensates the high-frequency part 431 of the signal. To generate the compensation torque command 45. In addition, the vibration suppression compensator 32' receives the motor speed 42 of the electric vehicle and the enable level 6 through the comparator 324, and compares the motor speed 42 with the enable level 6 to determine whether to compensate for the vibration suppression The output of the device 32' is set to 0, or set to the generated compensation torque command 45.

Similarly, in the embodiment of FIG. 4, the vibration suppression compensator 32' sets the output to 0 when the motor speed 42 is not less than the enable level 6, and when the motor speed 42 is less than the enable level 6 The output quantity is set to compensation torque command 45.

Refer to Figure 5, which is a signal comparison diagram before and after the vibration suppression compensator is set.

Fig. 5(a) shows the experimental data of the electric vehicle without applying the vibration suppression compensator 32 of the present invention. It can be seen from Fig. 5(a) that when the torque command 72 drops, the motor speed 71 will decrease, and when the motor speed 71 drops to a certain value, severe speed ripples (right side of the figure) will appear. These ripples can cause the aforementioned abnormal torsion or vibration of the electric vehicle, which in turn causes the driver's uncomfortable ride and the instability of the electric vehicle.

Fig. 5(b) shows the experimental data of the electric vehicle to which the vibration suppression compensator 32 or 32' of the present invention is applied. It can be clearly seen from Figure 5(b) that when the torque command 82 decreases, the motor speed 81 will also decrease. Only when the motor speed 81 drops to a certain value, there will be a little speed ripple (right side of the diagram). After that, the motor speed 81 can smoothly drop to zero. It can be seen that, with the vibration suppression compensator 32, 32' of the present invention, the abnormal torsion or vibration of the electric vehicle can be effectively suppressed, thereby improving the rider feeling of the driver.

Please continue to refer to FIG. 6, which is a flowchart of the vibration suppression method of the present invention. Figure 6 specifically discloses the vibration suppression method of the motor control system of the present invention, which is applied to an electric vehicle (based on the concise layout, and will be referred to as the vibration suppression method in the manual below). The vibration suppression method is mainly applied to The motor control system 3 shown in FIG. 2 is provided in any electric vehicle, electrically connected to the motor component 5 in the electric vehicle, and controls the operation of the motor component 5.

As shown in FIG. 6, in the present invention, the electric vehicle receives the input speed error signal 43 of the electric vehicle through the PID controller 31 in the motor control system 3 of the present invention (step S10), and the PID controller 31 The received input speed error signal 43 is calculated to generate the basic torque command 44 (step S12). Specifically, in step S10, the motor control system 3 mainly receives the speed signal 41 and the motor speed 42 of the electric vehicle itself, and subtracts the speed signal 41 and the motor speed 42 to obtain the input speed error signal 43.

In addition, the motor control system 3 also receives the input speed error signal 43 and the motor speed 42 of the electric vehicle itself through the internal vibration suppression compensator 32 (step S14), and performs a compensation gain on the input speed error signal 43 to generate Compensate the torque command 45 (step S16).

In one embodiment, the motor control system 3 uses a vibration suppression compensator 32 as shown in FIG. 3. Specifically, in step S16, the vibration suppression compensator 32 filters the input speed error signal 43 through the low-pass filter 321 to extract the low frequency part of the input speed error signal 43, and then passes the processor 322 to input The speed error signal 43 is subtracted from the low frequency part of the signal to extract the high frequency part 431 of the input speed error signal 43. Then, the vibration suppression compensator 32 performs a compensation gain on the signal high frequency part 431 through the gainer 323 to generate a compensation torque command 45.

In another embodiment, the motor control system 3 uses a vibration suppression compensator 32' as shown in FIG. Specifically, in step S16, the vibration suppression compensator 32' filters the input speed error signal 43 through the high-pass filter 325 to directly extract the high frequency part 431 of the input speed error signal 43. In addition, the vibration suppression compensator 32' then uses the gainer 323 to compensate the high frequency part 431 of the signal to generate a compensation torque command 45.

After step S16, the vibration suppression compensator 32, 32' further determines whether the current motor speed 42 of the electric vehicle is less than the preset enable level 6 (step S18). For example, the vibration suppression compensator 32, 32' can pass as The comparator 324 shown in FIG. 3 and FIG. 4 compares the motor speed 42 with the enable level 6. In addition, the vibration suppression compensator 32, 32' will set its output to the compensation torque command 45 when judging that the motor speed 42 is less than the enabling level 6 (step S20), and when judging that the motor speed 42 is not less than the enabling level 6, When the level is 6, the output is set to 0 (step S22).

Next, the motor control system 3 adds the basic torque command 44 and the output of the vibration suppression compensator 32 (ie, 0 in step S22 or the compensation torque command 45 in step S20) to generate the final output torque Command 46 (step S24), and transmit the output torque command 46 to the motor component 5 of the electric vehicle to control the operation of the motor component 5 (step S26).

In the present invention, the motor control system 3 will continue to determine whether the electric vehicle is closed (step S28), and continue and repeat steps S10 to S26 before the electric vehicle is closed to continuously output torque commands to the electric vehicle 46 Compensation is carried out to avoid abnormal torsion or vibration of the electric vehicle and affect the rider's feeling.

With the technical solution of the present invention, the electric vehicle can suppress abnormal torsion and vibration caused by the nonlinear characteristics of the transmission mechanism by the vibration suppression compensator 32, 32', thereby improving the riding comfort of the electric vehicle. In addition, the driver can determine the bandwidth used by the low-pass filter 321 and the high-pass filter 325 in the vibration suppression compensator 32, 32', the gain value used by the gainer 323, and the enable according to the type of electric vehicle. The level 6 etc. are adjusted individually, so that the vibration suppression compensator 32, 32' and the vibration suppression method of the present invention can be easily applied to various types of electric loads, which is quite convenient and flexible.

The above are only preferred specific examples of the present invention, and are not limited to the scope of the patent of the present invention. Therefore, all equivalent changes made by using the content of the present invention are included in the scope of the present invention in the same way. Bright.

11: PID controller

12: Input speed error signal

13: Torque command

2: gear

3: Motor control system

31: PID controller

32, 32’: Vibration suppression compensator

321: low pass filter

322: processor

323: Gainer

324: Comparator

325: high pass filter

41: Speed signal

42: Motor speed

43: Input speed error signal

431: signal high frequency part

44: Basic torque command

45: Compensation torque command

46: Output torque command

5: Motor components

6: Enable level

71, 81: Motor speed

72, 82: Torque command

W: Backlash distance

S10~S28: Control steps

Figure 1A is a block diagram of an electric vehicle in a speed control mode.

Figure 1B is a schematic diagram of the non-linear dead zone of the gear.

Figure 2 is a block diagram of the motor control system of the present invention.

Fig. 3 is a first embodiment of the block diagram of the vibration suppression compensator of the present invention.

FIG. 4 is a second embodiment of the block diagram of the vibration suppression compensator of the present invention.

Figure 5 shows the signal comparison diagram before and after the vibration suppression compensator is set.

Fig. 6 is a flowchart of the vibration suppression method of the present invention.

3: Motor control system

31: PID controller

32: Vibration suppression compensator

41: Speed signal

42: Motor speed

43: Input speed error signal

44: Basic torque command

45: Compensation torque command

46: Output torque command

5: Motor components

Claims (9)

A motor control system applied to an electric vehicle, including: A Proportional-Integral-Derivative (PID) controller receives an input speed error signal of the electric vehicle, and calculates the input speed error signal to generate a basic torque command; and A vibration suppression compensator, arranged in parallel with the PID controller, receives the input speed error signal and a motor speed of the electric vehicle, and compensates the input speed error signal to generate a compensation torque command; Wherein, the vibration suppression compensator sets an output value to 0 when judging that the motor speed is not less than the preset consistent energy level, and sets the output value as the compensation torque when judging that the motor speed is less than the enable level command; Wherein, the motor control system adds the basic torque command and the output of the vibration suppression compensator to generate an output torque command, and controls the operation of a motor component of the electric vehicle according to the output torque command. The motor control system according to claim 1, wherein the vibration suppression compensator includes: A low-pass filter for filtering the input speed error signal to extract a low frequency part of the input speed error signal; A processor, subtracting the input speed error signal from the low frequency part of the signal to extract a high frequency part of the input speed error signal; A gainer to compensate the high frequency part of the signal to generate the compensation torque command; and A comparator compares the rotation speed of the motor with the enable level. The motor control system according to claim 1, wherein the vibration suppression compensator includes: A high-pass filter for filtering the input speed error signal to extract a high frequency part of the input speed error signal; A gainer to compensate the high frequency part of the signal to generate the compensation torque command; and A comparator compares the rotation speed of the motor with the enable level. The motor control system according to claim 1, wherein the PID controller is a PI controller that sets a parameter of a differential unit to zero. A vibration suppression method for a motor control system is applied to a motor control system in an electric vehicle, and includes the following steps: a) A Proportional-Integral-Derivative (PID) controller in the motor control system receives an input speed error signal of the electric vehicle; b) The PID controller calculates the input speed error signal to generate a basic torque command; c) A vibration suppression compensator in the motor control system receives the input speed error signal and a motor speed of the electric vehicle; d) The input speed error signal is compensated by the vibration suppression compensator to generate a compensation torque command; e) The vibration suppression compensator sets an output value to 0 when judging that the motor speed is not less than the preset consistent energy level, and sets the output value as the compensation torque when judging that the motor speed is less than the enable level command; f) The motor control system adds the basic torque command and the output of the vibration suppression compensator to generate an output torque command; g) The motor control system transmits the output torque command to a motor component of the electric vehicle to control the operation of the motor component; and h) The motor control system continuously determines whether the electric vehicle is closed, and continues to execute the steps a) to g) before the electric vehicle is closed. The vibration suppression method of a motor control system according to claim 5, wherein the step a) is that the motor control system receives a speed signal of the electric vehicle and the motor speed, and compares the speed signal with the motor speed Subtract to obtain the input speed error signal. The vibration suppression method of the motor control system according to claim 5, wherein the step d) includes the following steps: d11) filtering the input speed error signal through a low-pass filter of the vibration suppression compensator to extract a low-frequency part of the input speed error signal; d12) Subtracting the input speed error signal from the low-frequency part of the signal by a processor of the vibration suppression compensator to extract a high-frequency part of the input speed error signal; and d13) Compensating the high frequency part of the signal through a gainer of the vibration suppression compensator to generate the compensation torque command; Wherein, the step e) is to compare the rotation speed of the motor with the enable level by a comparator of the vibration suppression compensator. The vibration suppression method of the motor control system according to claim 5, wherein the step d) includes the following steps: d21) filtering the input speed error signal through a high-pass filter of the vibration suppression compensator to extract a high frequency part of the input speed error signal; and d23) Compensating the high-frequency part of the signal through a gainer of the vibration suppression compensator to generate the compensation torque command; Wherein, the step e) is to compare the rotation speed of the motor with the enable level by a comparator of the vibration suppression compensator. The vibration suppression method of the motor control system according to claim 5, wherein the enable level is a specific speed or a speed range of the electric vehicle.

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