Driving control system and method for smoothly switching motor into medium-high speed interval from zero low speed

Abstract

The invention belongs to the technical field of motor control, and discloses a driving control system for smoothly switching a motor into a medium-high speed interval from zero low speed, and the working process is as follows: S1, setting an expected rotating speed of the motor, obtaining a feedback rotating speed, and calculating a rotating speed control quantity through a rotating speed control module; s2, based on the rotating speed control quantity of the rotating speed control module, calculating the three-phase PWM duty ratio of the driving power tube through the magnetic field orientation control module; s3, setting an expected current in a zero-low-speed open-loop stage, obtaining a switching target rotating speed, and generating electrical angle data information through a current frequency ratio control module; s4, calculating the difference value between the electrical angle output by the current frequency ratio control module and the electrical angle output by the sensorless observer, and smoothly transitioning an open loop to a closed loop through a smooth switching closed loop control module; and S5, back electromotive force is collected through an ADC, and the position of the rotor is predicted through a sensorless control module. According to the invention, smooth transition of the permanent magnet synchronous motor or the direct-current brushless motor from a zero low-speed starting stage to a medium-high-speed operation stage is successfully realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of motor control, and in particular relates to a drive control system and method for a motor to smoothly switch from a zero low speed to a medium and high speed range. Background Art

[0002] At present, with the energy crisis and energy-saving needs, new energy and electrification process, industrial automation and intelligence, power electronics technology and embedded control, the development of high-performance and high-efficiency permanent magnet synchronous motors or brushless DC motors has been effectively promoted. Permanent magnet synchronous motors or brushless DC motors are widely used in new energy vehicles (such as pure electric vehicles and plug-in hybrid vehicles, etc.), and are mainly used in automotive wheel hub electric drives, air conditioning compressor electric drives, electric power steering electric drives, etc. In order to reduce product costs, control systems using permanent magnet synchronous motors or brushless DC motors usually use sensorless observer control in situations where accuracy requirements are not high. The introduction of sensorless observers divides permanent magnet synchronous motors or brushless DC motors into two operating stages, mainly divided into: zero low-speed start-up stage and medium-high speed operation stage. Because the amplitude of the back electromotive force sampled by the ADC is small when the control of the permanent magnet synchronous motor or brushless DC motor is in the zero low-speed stage, the rotor position predicted by the sensorless observer is inaccurate, and there is a high probability that the permanent magnet synchronous motor or brushless DC motor will fail to start or operate abnormally.

[0003] Therefore, it is necessary to provide a smooth transition strategy or method to ensure that the permanent magnet synchronous motor or the brushless DC motor starts smoothly when it is in the zero low speed stage and smoothly transitions to the medium and high speed operation stage. Summary of the invention

[0004] In view of this, the purpose of the present invention is to provide a drive control system and method for smoothly switching a motor from zero low speed to a medium and high speed range. The present invention aims to solve the problem that the rotor position is not accurately predicted by the sensorless observer in the zero low speed range, which has a high probability of causing the permanent magnet synchronous motor or DC brushless motor to fail to start or run abnormally.

[0005] The present invention provides a drive control system for a motor to smoothly switch from zero low speed to a medium and high speed range, comprising a speed calculation control module, a magnetic field orientation control module, a current frequency ratio control module, a smooth switching closed-loop control module, and a sensorless observer control module;

[0006] Speed ​​calculation control module: calculates the speed control amount based on the expected speed set by the motor and the obtained feedback speed;

[0007] Field-oriented control module: Calculates the speed control quantity of the speed calculation control module and calculates the three-phase PWM duty cycle of the driving power tube;

[0008] Current frequency ratio control module: generates electrical angle data information based on the expected current in the set zero low-speed open-loop stage and the obtained switching target speed;

[0009] Smooth switching closed loop control module: used to smoothly transition from open loop to closed loop;

[0010] Sensorless observer control module: predicts the rotor position based on the back EMF collected by ADC.

[0011] The present invention also provides a method for smoothly switching a motor from a zero low speed to a medium and high speed range, comprising the following steps:

[0012] S1. Set the desired speed of the motor and obtain the feedback speed, and calculate the speed control amount through the speed control module;

[0013] S2. Based on the speed control amount of the speed control module, the three-phase PWM duty cycle of the driving power tube is calculated by the field oriented control module;

[0014] S3. Set the expected current in the zero low-speed open-loop stage, obtain the switching target speed, and generate electrical angle data information via the current-frequency ratio control module;

[0015] S4. Calculate the electrical angle difference between the output electrical angle of the current frequency ratio control module and the output electrical angle of the sensorless observer, and smoothly transition the open loop to the closed loop through the smooth cut closed loop control module;

[0016] When the motor is running at zero low speed stage, if the motor reference speed is less than the lower limit threshold of the switching interval speed, the current frequency ratio control is adopted to enable the motor to start at zero low speed with load;

[0017] When the motor is running at the zero low speed stage, if the motor reference speed is within the switching range, it will gradually prepare to transition to the medium and high speed operation stage;

[0018] When the motor is running at the zero low speed stage, if the motor reference speed is higher than the upper speed threshold of the switching interval, the closed loop is connected to enter the medium and high speed operation stage;

[0019] S5. Collect the back electromotive force through ADC and predict the rotor position through the sensorless control module.

[0020] Furthermore, the motor is a permanent magnet synchronous motor or a brushless DC motor.

[0021] Furthermore, in step S1, before setting the desired speed of the motor, it is necessary to first measure the desired parameters of the motor;

[0022] The desired parameters include stator internal resistance, dq axis Ld and Lq inductance, rotor pole pair number Pn, rotor flux and back electromotive force.

[0023] Furthermore, in step S1, the data input into the speed control module are all filtered.

[0024] Furthermore, in step S2, before calculating the three-phase PWM duty cycle of the driving power tube, it is necessary to analyze the PWM waveform generated by the Timer configured by the underlying MCU to ensure that the Timer is configured correctly and the PWM output pin works properly.

[0025] Furthermore, in step S3, when the electrical angle data information is generated via the current-frequency ratio control module, it is necessary to check the amplitude and phase of the back electromotive force collected by the ADC to ensure that the motor can be driven correctly and a virtual electrical angle can be generated for subsequent methods to ensure that the operation of subsequent algorithm strategies is not affected and to ensure that current closed-loop and speed open-loop control can be achieved based on the sampled current.

[0026] Furthermore, in the step S3 and the step S4, it is necessary to configure the mechanical parameters and software control parameters related to the current frequency ratio control module and the smoothing closed-loop control module.

[0027] Beneficial effects:

[0028] The present invention discloses a drive control system for a motor to smoothly switch from zero low speed to a medium and high speed interval, including a speed calculation control module, a magnetic field oriented control module, a current frequency ratio control module, a smooth closed-loop control module, and a sensorless observer control module. The main working process of the control system is as follows: S1. Set the expected speed of the motor and obtain the feedback speed, and calculate the speed control amount through the speed control module; S2. Based on the speed control amount of the speed control module, calculate the three-phase PWM duty cycle of the driving power tube through the magnetic field oriented control module; S3. Set the expected current in the zero low speed open loop stage, obtain the switching target speed, and generate electrical angle data information through the current frequency ratio control module; S4. Calculate the difference between the electrical angle output by the current frequency ratio control module and the electrical angle output by the sensorless observer, and smoothly transition the open loop to the closed loop through the smooth closed-loop control module; S5. Collect the reverse electromotive force through the ADC, and predict the rotor position through the sensorless control module. The present invention successfully solves the problem of the permanent magnet synchronous motor or the DC brushless motor smoothly transitioning from the zero low speed starting stage to the medium and high speed operation stage.

[0029] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and to some extent, will be obvious to those skilled in the art based on the following examination and study, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1A flow chart of a method for smoothly switching a motor from zero low speed to a medium-high speed range according to the present invention;

[0031] Figure 2 It is a current frequency ratio control system;

[0032] Figure 3 are the actual rotating coordinate system and the virtual rotating coordinate system;

[0033] Figure 4 It is an exponential smooth transition curve;

[0034] Figure 5 Exponential transition process Changing trends;

[0035] Figure 6 It is a control process that smoothly transitions from zero low speed to medium and high speed. DETAILED DESCRIPTION

[0036] In order to make the technical solutions, advantages and purposes of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the described embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work belong to the protection scope of this application.

[0037] Permanent magnet synchronous motor or DC brushless motor can be divided into two stages according to the speed in the field of sensorless control. The first stage is the zero low-speed start-up stage. The characteristics of this stage are that it works in the low-speed range, the speed is low, the amplitude of the reverse electromotive force collected by the ADC is small, and the rotor position predicted by the sensorless algorithm is inaccurate, which can easily lead to startup failure or abnormal operation. The second stage is the medium-high speed operation stage. The characteristics of this stage are that it works in the high-speed range, the speed is high, the amplitude of the reverse electromotive force collected by the ADC is large, and the rotor position predicted by the sensorless algorithm is close to the actual rotor position, which can drive and control the permanent magnet synchronous motor or DC brushless motor normally. In summary, since it is difficult to predict the actual rotor position of the permanent magnet synchronous motor or DC brushless motor in the zero low-speed start-up stage of sensorless control, and the rotor position is more accurately predicted in the medium-high speed stage, a transition stage is inserted between the zero low-speed start-up stage and the medium-high speed operation stage.

[0038] In view of this, the present invention provides a drive control system for a motor to smoothly switch from zero low speed to a medium and high speed range, including a speed calculation control module, a magnetic field orientation control module, a current frequency ratio control module, a smooth switching closed-loop control module, and a sensorless observer control module;

[0039] Speed ​​calculation control module: calculates the speed control amount based on the expected speed set by the motor and the obtained feedback speed;

[0040] Field-oriented control module: Calculates the speed control quantity of the speed calculation control module and calculates the three-phase PWM duty cycle of the driving power tube;

[0041] Current frequency ratio control module: generates electrical angle data information based on the expected current in the set zero low-speed open-loop stage and the obtained switching target speed;

[0042] Smooth switching closed loop control module: used to smoothly transition from open loop to closed loop;

[0043] Sensorless observer control module: predicts the rotor position based on the back EMF collected by ADC.

[0044] like Figure 1 As shown, the present invention also provides a method for smoothly switching a motor from a zero low speed to a medium and high speed range, comprising the following steps:

[0045] S1. Set the desired speed of the motor and obtain the feedback speed, and calculate the speed control amount through the speed control module;

[0046] The motor in this embodiment is a permanent magnet synchronous motor or a brushless DC motor;

[0047] S2. Based on the speed control amount of the speed control module, the three-phase PWM duty cycle of the driving power tube is calculated by the field oriented control module;

[0048] S3. Set the expected current in the zero low-speed open-loop stage, obtain the switching target speed, and generate electrical angle data information via the current-frequency ratio control module;

[0049] S4. Calculate the electrical angle difference between the output electrical angle of the current frequency ratio control module and the output electrical angle of the sensorless observer, and smoothly transition the open loop to the closed loop through the smooth cut closed loop control module;

[0050] When the motor is running at zero low speed stage, if the motor reference speed is less than the lower limit threshold of the switching interval speed, the current frequency ratio control is adopted to enable the motor to start at zero low speed with load;

[0051] When the motor is running at the zero low speed stage, if the motor reference speed is within the switching range, it will gradually prepare to transition to the medium and high speed operation stage;

[0052] When the motor is running at the zero low speed stage, if the motor reference speed is higher than the upper speed threshold of the switching interval, the closed loop is connected to enter the medium and high speed operation stage;

[0053] S5. Collecting the back electromotive force through ADC and predicting the rotor position through the sensorless control module;

[0054] The sensorless control module predicts the rotor position based on the back-EMF signal after obtaining the reliable back-EMF of each phase.

[0055] The present invention successfully realizes the function of a permanent magnet synchronous motor or a brushless DC motor smoothly transitioning from a zero low speed starting stage to a medium and high speed running stage, and solves or improves the problem of inaccurate rotor position prediction by a sensorless observer in a zero low speed range.

[0056] As a preferred embodiment of this embodiment, before performing drive control of the permanent magnet synchronous motor or the brushless DC motor, it is necessary to perform mechanical parameter measurement and software configuration on the permanent magnet synchronous motor or the brushless DC motor, including: configuring the underlying drive and setting the drive waveform period; measuring the mechanical parameters and setting the measured parameters into the control algorithm software.

[0057] As a preferred embodiment of the present embodiment, before performing the drive control of the permanent magnet synchronous motor or the brushless DC motor, firstly, the stator internal resistance, dq axis Ld and Lq inductance, rotor pole pair number Pn, rotor flux or back electromotive force and other parameters of the permanent magnet synchronous motor or the brushless DC motor are measured or estimated through a digital bridge, a multimeter, and an oscilloscope. Secondly, the measured mechanical parameters of the permanent magnet synchronous motor or the brushless DC motor are input into the control algorithm to configure the software parameters. The open-loop control drive control board (without connecting the permanent magnet synchronous motor or the brushless DC motor) is used again to check whether the relevant waveforms output by the configured software meet the normal standards through an oscilloscope, a multimeter, and a current clamp. If the feedback data waveform has met the standards, it can be determined that the control board, the power tube, the related MCU underlying driver, the wiring of the permanent magnet synchronous motor or the brushless DC motor and the control board are all working normally.

[0058] After the above operations, it can be determined that the software and hardware control systems of the permanent magnet synchronous motor or the brushless DC motor are in normal working condition, and then the relevant control parameters of the speed control module are set to ensure that the control system operates according to the desired goal. The data information input to the speed control module will have jitter or oscillation, which affects the calculation output of the speed control module. Therefore, it is necessary to filter the input data information to reduce jitter or oscillation to prevent it from affecting the operation of subsequent algorithm strategies.

[0059] The filtering process is as follows: first set the low-pass filter parameters, input the speed signal into the filter, perform iterative processing to eliminate jitter and oscillation, and finally input the filtered speed signal into the speed control module.

[0060] As a preferred embodiment of this embodiment, before performing magnetic field oriented control, it is necessary to check the amplitude and phase of the ADC sampled back electromotive force to ensure that the motor can be driven correctly and a virtual electrical angle can be generated for subsequent strategies and methods to ensure that the operation of subsequent algorithm strategies is not affected and to ensure that current closed-loop and speed open-loop control can be achieved based on the sampled current.

[0061] As a preferred embodiment of this embodiment, after obtaining the reliable target data output by the speed control module, the magnetic field oriented control module needs to configure relevant parameters to ensure that the pulse width modulation waveform of the drive motor can be correctly output.

[0062] As a preferred embodiment of this embodiment, it is necessary to analyze the underlying driving waveform to ensure that the controller can output the correct driving waveform or collect the correct current waveform according to the control algorithm, including:

[0063] First, determine the I / O port that drives the permanent magnet synchronous motor or brushless DC motor. Use an oscilloscope to detect whether the PWM output waveform is correct according to the specific I / O port. Finally, determine the I / O port that collects the back EMF. Use a current clamp to detect whether the back EMF waveform is valid according to the specific I / O port.

[0064] Before calculating the three-phase PWM duty cycle of the driving power tube, it is necessary to analyze the PWM waveform generated by the Timer configured by the underlying MCU to ensure that the Timer is configured correctly and the PWM output pin works properly.

[0065] As a preferred embodiment of this embodiment, under the premise of ensuring that the controller hardware and software can work normally, the permanent magnet synchronous motor or DC brushless motor drive control is performed, and the mechanical parameters and software control parameters related to the current frequency ratio control module and the smooth cut closed loop control module need to be configured in the zero low speed starting stage, including:

[0066] like Figure 2 As shown, for current frequency ratio control, it is necessary to establish a mathematical model of surface mounted permanent magnet synchronous motor or DC brushless motor:

[0067]

[0068] Where: u d 、u q are the stator d and q axis voltages, R s is the stator phase resistance, w r is the motor electrical angular velocity.

[0069] like Figure 3 As shown, Figure 3 The left is the actual rotating coordinate system (before the current frequency ratio is started). Figure 3The right is the virtual rotating coordinate system (after the current frequency ratio is started). Since the current frequency ratio control is in the form of current closed loop and speed open loop control, it is necessary to pre-set the q-axis current of the virtual coordinate system and generate a virtual rotor angle to drive the permanent magnet synchronous motor or DC brushless motor. It is necessary to calculate the q-axis current in the virtual rotating coordinate system set by the current frequency ratio control module and project it into the actual rotating coordinate system to obtain the q-axis current that drives the permanent magnet synchronous motor or DC brushless motor:

[0070]

[0071] Where: i q , are the q-axis currents of the actual rotating coordinate system and the virtual rotating coordinate system respectively.

[0072] From the above q-axis current, the electromagnetic torque can be obtained:

[0073]

[0074] Where: T e 、p n 、i q , Δθ are the electromagnetic torque, pole pair number, q-axis current in the actual rotating coordinate system, q-axis current in the virtual rotating coordinate system, rotor flux, sensorless observer angle and current frequency ratio control angle difference.

[0075] Since the current frequency is higher than the open-loop control period T e It fluctuates. When the switching moment is reached, if T e If it is too small, the speed will drop after switching, while if it is too large, the speed will overshoot. Therefore, the optimal switching torque during the switching process must be determined:

[0076]

[0077] Where: is the optimal average current; m is the total number of sampling times before switching; j is the sampling time before switching.

[0078] From the optimal average current, the optimal average torque during the switching process can be determined:

[0079]

[0080] Where: T eavg 、p n , They are the optimal average torque, pole pair number, optimal average current, and rotor flux respectively.

[0081] After obtaining the actual q-axis current and the optimal average current, the permanent magnet synchronous motor or brushless DC motor can be controlled to start in an open loop by the current-frequency ratio, the upper and lower speed limits of the transition interval can be set, and the electrical angular velocity weight piecewise function can be set according to the reference speed:

[0082]

[0083] Where: k wc 、w ref , w1, and w2 are the electrical angular velocity weight coefficient, the reference electrical angular velocity, the lower limit of the electrical angular velocity in the switching interval, and the upper limit of the electrical angular velocity in the switching interval, respectively.

[0084] like Figure 4 As shown in the figure, after the weight coefficients of the three intervals are obtained by calculating the electrical angular velocity based on the current frequency ratio control, the weighted piecewise function of the angle-weighted exponential smooth transition curve of the permanent magnet synchronous motor or the DC brushless motor from the zero low-speed starting stage to the medium-high speed operation stage can be designed according to the coefficients:

[0085]

[0086] Where: Angle wc 、w ref 、w1、w2、 They are respectively the electrical angle weight coefficient, the reference electrical angular velocity, the lower limit of the electrical angular velocity in the switching interval, the upper limit of the electrical angular velocity in the switching interval, the transition exponential curve, and the transition composite exponential curve.

[0087] like Figure 5 As shown, when the permanent magnet synchronous motor or the brushless DC motor reaches the transition interval speed under the control based on the current frequency ratio, in order to ensure that the current does not suddenly change during the transition process, the above-mentioned exponential transition curve and the mechanical torque attack angle self-balancing characteristics are used to ensure that the current does not suddenly change during the switching process. The control current smoothly decreases in an exponential function curve, and the transition process is smooth and reliable, which can effectively avoid the current and speed oscillation of the permanent magnet synchronous motor or the brushless DC motor during the transition from the zero low speed stage to the medium and high speed stage.

[0088]

[0089] Where: Angle wc They are the control current, optimal average current and electrical angle weight coefficient in the transition process respectively.

[0090] like Figure 6As shown, in summary, the transition process of the permanent magnet synchronous motor or the brushless DC motor from the zero low speed stage to the medium and high speed stage can be divided into: first, the expected control current of the current frequency ratio control module is set according to the size of the load; secondly, the current frequency ratio control module calculates the electrical angle required to drive the motor based on the transition target speed; then the upper and lower speed thresholds of the transition interval of the smooth cut closed-loop control module are set, and the reference speed is detected in the computer control system to see whether it has reached the speed range of the transition interval, and the electrical angular velocity weight coefficient and the exponential transition curve weight coefficient are calculated, and the q-axis control current in the transition process is calculated based on the exponential transition curve; finally, when the reference speed is greater than the upper threshold of the transition interval, the current frequency ratio control is stopped, and the sensorless algorithm is connected. At this time, the permanent magnet synchronous motor or the brushless DC motor successfully switches from the zero low speed stage to the medium and high speed stage.

[0091] It is hereby declared that the above embodiments are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention is described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solutions, which should be included in the scope of the claims of the present invention.

Claims

1. A drive control system for a motor to smoothly switch from zero low speed to a medium and high speed range, characterized in that: It includes a speed calculation control module, a magnetic field oriented control module, a current frequency ratio control module, a smooth cut closed loop control module, and a sensorless observer control module; Speed ​​calculation control module: calculates the speed control amount based on the expected speed set by the motor and the obtained feedback speed; Field-oriented control module: Calculates the speed control quantity of the speed calculation control module and calculates the three-phase PWM duty cycle of the driving power tube; Current frequency ratio control module: generates electrical angle data information based on the expected current in the set zero low-speed open-loop stage and the obtained switching target speed; Smooth switching closed loop control module: used to smoothly transition from open loop to closed loop; Sensorless observer control module: predicts the rotor position based on the back EMF collected by ADC.

2. A method for smoothly switching a motor from zero low speed to a medium-high speed range, characterized in that: The following steps are involved: S1. Set the desired speed of the motor and obtain the feedback speed, and calculate the speed control amount through the speed control module; S2. Based on the speed control amount of the speed control module, the three-phase PWM duty cycle of the driving power tube is calculated by the field oriented control module; S3. Set the expected current in the zero low-speed open-loop stage, obtain the switching target speed, and generate electrical angle data information via the current-frequency ratio control module; S4. Calculate the electrical angle difference between the output electrical angle of the current frequency ratio control module and the output electrical angle of the sensorless observer, and smoothly transition the open loop to the closed loop through the smooth cut closed loop control module; When the motor is running at zero low speed stage, if the motor reference speed is less than the lower limit threshold of the switching interval speed, the current frequency ratio control is adopted to enable the motor to start at zero low speed with load; When the motor is running at the zero low speed stage, if the motor reference speed is within the switching range, it will gradually prepare to transition to the medium and high speed operation stage; When the motor is running at the zero low speed stage, if the motor reference speed is higher than the upper speed threshold of the switching interval, the closed loop is connected to enter the medium and high speed operation stage; S5. Collect the back electromotive force through ADC and predict the rotor position through the sensorless control module.

3. The method for smoothly switching a motor from zero low speed to a medium-high speed range according to claim 2, characterized in that: The motor is a permanent magnet synchronous motor or a brushless DC motor.

4. The method for smoothly switching a motor from zero low speed to a medium-high speed range according to claim 2, characterized in that: In the step S1, before setting the expected speed of the motor, it is necessary to first measure the expected parameters of the motor; The desired parameters include stator internal resistance, dq axis Ld and Lq inductance, rotor pole pair number Pn, rotor flux and back electromotive force.

5. The method for smoothly switching a motor from zero low speed to a medium-high speed range according to claim 2, characterized in that: In step S1, the data input to the speed control module are all filtered.

6. The method for smoothly switching a motor from zero low speed to a medium-high speed range according to claim 2, characterized in that: In step S2, before calculating the three-phase PWM duty cycle of the driving power tube, it is necessary to analyze the PWM waveform generated by the Timer configured by the underlying MCU to ensure that the Timer is configured correctly and the PWM output pin works normally.

7. The method for smoothly switching a motor from zero low speed to a medium-high speed range according to claim 2, characterized in that: In step S3, when the electrical angle data information is generated by the current-frequency ratio control module, it is necessary to check the amplitude and phase of the back electromotive force collected by the ADC to ensure that the motor can be driven correctly and a virtual electrical angle can be generated for subsequent methods to ensure that the operation of subsequent algorithm strategies is not affected and to ensure that current closed-loop and speed open-loop control can be achieved based on the sampled current.

8. The method for smoothly switching a motor from zero low speed to a medium-high speed range according to claim 2, characterized in that: In the step S3 and the step S4, it is necessary to configure the mechanical parameters and software control parameters related to the current frequency ratio control module and the smoothing closed-loop control module.

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