A simulation teaching platform for DC servo motor control

Abstract

The invention discloses a simulation teaching platform for control of a pair of direct current servo motors, comprising: a PC, which is installed with algorithm simulation software and upper computer monitoring software; a real-time simulation controller, which is used for parsing the algorithm simulated by the algorithm simulation software into control signals and parameters corresponding to various physical devices; a direct current drive control box, which is used for driving the servo motor to run; a pair of motors, which is installed with a servo motor and a pair of motors, and the servo motor is driven by the direct current drive control box; an encoder for detecting the rotation angle of the pair of output shafts is installed in the pair of motors, the encoder is communicatively connected with a digital signal adapter board module in the direct current drive control box, and a signal end of the digital signal adapter board module is communicatively connected with a signal end of the real-time simulation controller; a digital input and output and an analog acquisition output of a PLC built in the direct current drive control box are connected to a digital port and an analog port of the real-time simulation controller, and the PC is connected to the real-time simulation controller via Ethernet communication.

Description

Technical Field

[0001] The invention relates to a control technology for a pair of direct current servo motors, and in particular to a control simulation teaching platform for a pair of direct current servo motors. Background Art

[0002] In recent years, with the rapid development and application of motor control technology and automatic control research, traditional teaching aids experimental platforms are difficult to meet the requirements of students' modern education. New teaching aids platforms with exploratory, intuitive, scientific, rich and open characteristics have become an urgent need for colleges and universities to establish new laboratories. At the same time, traditional education has a certain degree of disconnection in teaching-scientific research-application, so platforms with teaching and scientific research applications have gradually attracted people's attention. As the most common and basic control equipment, the speed control and position control of DC servo motors involve the basic concept understanding of automatic control principles, motor control theory, motion control and other aspects, which have certain practical significance. Therefore, the teaching platform of DC servo motor control platform has received more and more attention. In addition, in order to reduce the time cost of teaching expansion and research and improve testing efficiency, it is particularly necessary to develop a DC servo motor control simulation teaching and research platform with good compatibility and scalability, providing a fast and convenient development environment, integrating multiple research environments and safe and reliable. Summary of the invention

[0003] In view of the above-mentioned defects of the prior art, the technical problem to be solved by the present invention is to provide a DC servo motor control simulation teaching platform, which has good compatibility and scalability, can provide a fast and convenient development environment, and has the characteristics of high integration, safety and reliability.

[0004] To achieve the above object, the present invention provides a DC servo motor control simulation teaching platform, comprising:

[0005] A PC is installed with algorithm simulation software and host computer monitoring software, wherein the algorithm simulation software is used for performing algorithm simulation on the PC side, and the host computer monitoring software is used for realizing monitoring information or inputting control information through a screen;

[0006] A real-time simulation controller is used to analyze the control signals and parameters corresponding to each physical device according to the algorithm simulated by the algorithm simulation software;

[0007] DC drive control box, used to drive the servo motor to operate;

[0008] The towing motor group is equipped with a servo motor and a towing motor, and the servo motor is driven by a DC drive control box; an encoder for detecting the rotation angle of the towing output shaft is installed in the towing motor, and the encoder is communicatively connected with a digital signal adapter board module in the DC drive control box, and the signal end of the digital signal adapter board module is communicatively connected with the signal end of the real-time simulation controller;

[0009] The digital input and output and analog acquisition output of the built-in PLC in the DC drive control box are connected to the digital port and analog port of the real-time simulation controller, and the PC is connected to the real-time simulation controller via Ethernet communication.

[0010] Preferably, the DC drive control box includes a 48V DC drive power supply, a 24V DC control power supply, a motor drive board, a terminal block and a digital signal adapter board module, and the signal end of the PLC built into the DC drive control box is communicatively connected with the signal end of the real-time simulation controller.

[0011] Preferably, the PC is used for software for teaching and researching the towing DC servo motor, and also displays the basic electrical parameters and working conditions of the two motors on the platform through the display interface; the real-time simulation controller is used to run the simulation model established by the PC, and is connected to the PC through Ethernet to exchange collected information and control instructions; the real-time simulation controller is connected to the DC drive control box via a signal line to exchange control signals, motor position information, and motor enable signals; the servo motor on the towing motor group is connected to the DC drive control box via a power cable, and is powered by the DC drive control box; the encoder of the towing motor is connected to the PLC signal terminal via a signal cable to provide an encoder signal to the DC drive control box.

[0012] Preferably, a protection module is further included, the protection module includes a base, the base is fixed on the frame of the towing motor group, and a protection cover is fixed on the base, the inside of the protection cover is an inner cover, and the inner cover covers the outside of the servo motor and the towing motor;

[0013] A support tube is fixed at the corresponding position of the base and the inner cover, a sealing gas ring is sleeved on the support tube, and the inner bottom of the support tube is connected to one end of the exhaust pipe, and the other end of the exhaust pipe is connected to the inner cover;

[0014] The interior of the sealing air ring is connected to one end of the sealing intake pipe and the sealing exhaust pipe respectively, and the other ends of the sealing intake pipe and the sealing exhaust pipe are connected to the parts of the switching inner cavity located on both sides of the piston respectively. The switching inner cavity is arranged in the switching shell of the switching valve.

[0015] Preferably, the protective cover is made of transparent, fireproof and heat-insulating material.

[0016] Preferably, the piston is provided with an upper trumpet groove and a lower trumpet hole, the upper trumpet groove and the lower trumpet hole are interconnected and penetrate the piston, and a limit rod is fixed on one end of the piston, a limit protrusion is fixed at a position corresponding to the switching inner cavity and the limit rod, and a first interval is provided between the limit rod and the limit protrusion;

[0017] The switching inner cavity is connected to one end of the sealed intake pipe and is also connected to one end of the first intake pipe and the second intake pipe respectively. The other ends of the first intake pipe and the second intake pipe are connected to one end of the main intake pipe respectively. The main intake pipe is connected to the exhaust port of the air pump, and the air pump is used to pump external air into the main intake pipe. A compression spring is also installed between the limit rod and the limit protrusion, and the piston is sealed with the switching inner cavity and can be axially slidably assembled.

[0018] Preferably, a limiting cylinder is fixed on one end of the switching inner cavity communicating with the sealed exhaust pipe, a through-gas groove is provided on the limiting cylinder, and one end of the switching inner cavity provided with the limiting cylinder is also communicated with the gas nozzle;

[0019] In the initial state, the upper horn groove is connected with one end of the air inlet pipe, and the other end of the air inlet pipe enters the inner cover and is opposite to the top of the inner cover; the piston is fitted or tightly attached to the end face of the limit cylinder under the elastic force of the compression spring, and the air nozzle is in a closed state; the piston is not fitted and assembled with the first air inlet pipe, the second air inlet pipe and the connection point of the switching inner cavity; the lower horn groove is in a sealed state due to the sealing effect of the piston.

[0020] Preferably, the minimum distance L1 from the upper trumpet groove to the connection point between the sealed air intake pipe and the switching inner cavity is greater than the minimum distance L2 from the lower trumpet groove to the connection point between the first air intake pipe and the switching inner cavity.

[0021] Preferably, it also includes a water cooling system, the water cooling system includes a water cooling box, the water cooling box includes a box body, the inside of the box body is an inner box, a spirally arranged water cooling pipe is installed inside the inner box, both ends of the water cooling pipe respectively pass through the box body and are respectively connected to one end of the air intake joint and the exhaust joint, the main air intake pipe is cut into two sections and respectively connected in series to the air intake joint and the exhaust joint;

[0022] The top of the inner box is connected to the water inlet pipe and the bottom is connected to the drain pipe. The water inlet pipe is connected to the inlet of the cooler, the inlet of the cooler is connected to the outlet of the water pump, the inlet of the water pump is connected to the water in the water tank, and the inside of the water tank is also connected to the drain pipe.

[0023] Preferably, a heat conducting pipe is installed in the inner box, one end of the heat conducting pipe is open and the open end is assembled and fixed with the orifice plate, a plurality of through-holes are arranged on the orifice plate, and the communicating holes connect the inner box with the inside of the heat conducting pipe, a driving plug is also installed in the heat conducting pipe, a memory spring is installed between the driving plug and the orifice plate, and both ends of the memory spring are respectively assembled and fixed with the driving plug and the orifice plate;

[0024] The driving plug is sealed inside the heat conducting tube and can be assembled axially upward, and the driving plug is assembled and fixed with one end of the trigger rod, and the other end of the trigger rod passes through the heat conducting tube and faces the trigger end of the micro switch, the access end of the micro switch is conductively connected to the output end of the constant current source, the access end of the constant current source is conductively connected to the power supply, and the constant current source is used to convert the power supply into direct current with a stable voltage;

[0025] The output end of the micro switch is conductively connected to the control end of the contactor, the input end of the contactor is conductively connected to the power supply, and the output end is conductively connected to the power connection end of the cooler.

[0026] Preferably, the memory spring shortens at temperatures below 30°C and lengthens at temperatures between 50°C and 60°C.

[0027] Preferably, the air inlet of the air pump is connected to the outlet of the electromagnetic reversing valve, the first inlet of the electromagnetic reversing valve is connected to the external atmosphere, and the second inlet is connected to the exhaust pipe. The control end of the electromagnetic reversing valve is communicatively connected to the signal end of the real-time simulation controller. A temperature sensor is installed in the inner cover, and the signal end of the temperature sensor is communicatively connected to the signal end of the PLC, and the temperature sensor is used to detect the air temperature inside the inner cover; the electromagnetic reversing valve is used to select one of the first inlet, the second inlet and the outlet to be connected. In the initial state, the first inlet of the electromagnetic reversing valve is connected to the outlet of the electromagnetic reversing valve.

[0028] The beneficial effects of the present invention are:

[0029] 1) The present invention is guided by modern scientific research, has good open source, compatibility and extensibility, and not only provides a transparent control underlying model, but also provides a large number of interfaces and matching adapter boards to facilitate users to carry out subsequent expansion development and research.

[0030] 2) The present invention has a fast and convenient development environment, adopts a real-time simulation controller, and can achieve seamless connection with MATLAB / Simulink. Through rapid modeling and updating, it can help users quickly and truly feel the principles, and real-time parameter adjustment helps users to explore. It is also very convenient to store data, and a large amount of complex computing capabilities provide a basis for users to innovate.

[0031] 3) The bottom layer of the present invention is open and scientifically oriented, and can integrate multiple operating states. Therefore, it can quickly develop and switch experiments required for various teaching and scientific research occasions without changing the hardware, and can adapt to various teaching and scientific research requirements.

[0032] 4) The present invention has a simple and complete safety protection system (automatically matching and controlling various parameters to prevent accidents) and a reliable operating environment. While improving the richness, practicality and efficiency of teaching and scientific research, it can also ensure the safety of students and scientific researchers. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a structural block diagram of the present invention.

[0034] Figure 2 It is a schematic diagram of the structure of the towed motor set of the present invention.

[0035] Figure 3 It is a schematic diagram of the structure of the tow motor unit of the present invention (viewed from above).

[0036] Figure 4 It is a schematic diagram of the switching valve structure of the present invention.

[0037] Figure 5 It is a schematic diagram of the water cooling box structure of the present invention.

[0038] Figure 6 yes Figure 5 Enlarged view of F1 in the middle.

[0039] Figure 7 It is a block diagram of the water cooling system of the present invention. DETAILED DESCRIPTION

[0040] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0041] In the description of the present invention, it is necessary to understand that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0042] Embodiment 1

[0043] See also Figure 1 , a DC servo motor control simulation teaching platform, comprising:

[0044] The PC is installed with algorithm simulation software and host computer monitoring software. The algorithm simulation software is used for algorithm simulation on the PC side. In this embodiment, the algorithm simulation software adopts MATLAB and / or Simulink. The host computer monitoring software is used to realize monitoring information or input control information through the screen (a host computer software interface for displaying various measurement signals, intermediate signals, issuing instructions, and storing data), including graphics and numerical plug-ins for displaying variables and parameters of real-time application programs when running, input controls for real-time setting and changing running algorithm parameters, storage of experimental data and functions that can be converted to mat format, and also provides a wealth of software modules (such as software interfaces for docking with various software) to cope with various situations.

[0045] The real-time simulation controller is used to resolve the control signals and parameters corresponding to each physical device according to the algorithm simulated by the algorithm simulation software. In this embodiment, the real-time simulation controller uses a control module based on the dSPACE real-time simulation system or directly uses the dSPACE real-time simulation system. In this embodiment, the real-time simulation controller has more than 100 input / output interfaces, including analog input / output, digital input / output, CAN, RS485, Ethernet and incremental / Hall position encoder interfaces.

[0046] The DC drive control box is used to drive the servo motor to operate. It includes a 48V DC drive power supply, a 24V DC control power supply, a motor drive board (motor driver), a terminal block (wiring panel) and a digital signal adapter board module (data acquisition card). The DC drive control box can collect platform encoder, switch status, PWM drive and other signals; the DC drive control box can isolate signal interference, and its signal end is connected to the signal end of the real-time simulation controller to protect the real-time simulation controller and drive the servo motor.

[0047] The towing motor group is equipped with a servo motor and a towing motor. The servo motor is driven by a DC drive control box. An encoder for detecting the rotation angle of the towing output shaft is installed in the towing motor. The encoder is communicated with the digital signal adapter board module in the DC drive control box. The signal end of the digital signal adapter board module is communicated with the signal end of the real-time simulation controller, thereby inputting the signal output by the encoder into the real-time simulation controller.

[0048] The digital input and output and analog acquisition output of the DC drive control box are connected to the digital port and analog port of the real-time simulation controller. The PC and the real-time simulation controller are connected via Ethernet communication to exchange data in real time. The wiring and installation of the traction generator set can directly adopt the existing technology.

[0049] The PC in this embodiment is used for software for teaching and researching the towing DC servo motor, and also displays the basic electrical parameters and working conditions of the two motors on the platform through the display interface; the real-time simulation controller is used to run the simulation model established by the PC, and is connected to the PC through Ethernet to exchange collected information and control instructions; the real-time simulation controller is connected to the DC drive control box via a signal line to exchange control signals, motor position information, and motor enable signals; the servo motor on the towing motor group is connected to the DC drive control box via a power cable, and is powered by the DC drive control box; the incremental encoder of the towing motor is connected to the DC drive control box via a signal cable to provide an encoder signal to the DC drive control box; the output shafts of the towing motor and the servo motor are connected via a connecting shaft.

[0050] When implementing simulation teaching or research on the control of a pair of DC servo motors, first complete the offline simulation based on MATLAB on the PC, complete the theoretical study based on MATLAB, and obtain the ideal simulation structure. Then, on this basis, delete the models of the motor components, drive components, power modules, etc. used in the simulation, and change the model breakpoints to connect the actual input / output ports according to the real-time interface module and its pin definition provided by the real-time simulation controller, complete the compilation and automatic loading of the program on the real-time simulation controller, call or design the upper computer monitoring software interface, observe or drag the appropriate instrument / display control of the variable, and finally run the real-time simulation controller, connect the DC drive control box, the pair of motor units, the real-time simulation controller, and the PC, and you can quickly complete the connection of the simulation teaching or research platform for the control of a pair of DC servo motors.

[0051] Specific operation process: First, through the PC-side program setting, the set program is run in the real-time simulation controller, the real-time simulation controller issues instructions to the servo motor, changes the instruction size, observes the changes in the encoder curve, and completes the open-loop test. Similarly, through the PC-side program setting, the set program is run in the real-time simulation controller, and the real-time simulation controller gives instructions to the DC drive control box to output the specified current, speed or position, change the current instruction or speed, position target, and display the changes through the host computer monitoring software, so as to realize the measurement and calibration of the parameters such as the position control and speed control performance indicators of the towing motor by the algorithm used. The algorithm can be developed by the system users themselves or adopt existing technologies.

[0052] By setting the simulation algorithm on the PC side and changing the parameters of the real-time simulation controller, the output current of the DC drive control box can be controlled. By using the PC's visual interface to detect power in real time, record the two drive current signals and the feedback motor encoder signals, the safe and stable operation of the entire platform can be achieved, thereby improving the efficiency of teaching and research and development.

[0053] Embodiment 2

[0054] See also Figure 2-Figure 4 In actual use, since the servo motor 420 and the pair motor 430 generate relatively large amounts of heat when they are running, and the exposed servo output shaft 421 and the pair output shaft 431 rotate, there are great safety hazards if they are not protected. Therefore, the applicant has added a protection module.

[0055] The protection module 200 includes a base 110 of the entire platform, the base 110 is fixed on the frame of the towing motor group, and a protection cover 210 is fixed on the base 110, the protection cover 210 is made of transparent, fireproof and heat-insulating materials, and the inside of the protection cover 210 is an inner cover 211, and the inner cover 211 covers the outside of the servo motor 420 and the towing motor 430;

[0056] A support tube 120 is fixed at the corresponding position of the base 110 and the inner cover 211. A sealing air ring is mounted on the support tube 120, and the inner bottom of the support tube 120 is connected to one end of the exhaust pipe 342. The other end of the exhaust pipe 342 is connected to the inner cover 211, so as to discharge the airflow inside the inner cover.

[0057] The interior of the sealing gas ring 410 is respectively connected to one end of the sealing air inlet pipe 331 and the sealing air exhaust pipe 332, and the other ends of the sealing air inlet pipe 331 and the sealing air exhaust pipe 332 are respectively connected to the parts of the switching inner cavity 511 located on both sides of the piston 520, and the switching inner cavity 511 is arranged in the switching housing 510 of the switching valve;

[0058] The piston 520 is provided with an upper trumpet groove 522 and a lower trumpet hole 521, the upper trumpet groove 522 and the lower trumpet hole 521 are connected to each other and penetrate the piston 520, and a limiting rod 561 is fixed on one end of the piston 520, and a limiting protrusion 562 is fixed at a position corresponding to the switching inner cavity 511 and the limiting rod 561, and a first interval is formed between the limiting rod 561 and the limiting protrusion 562;

[0059] The switching inner cavity 511 is connected to the sealed air inlet pipe 331 at one end and is also connected to one end of the first air inlet pipe 351 and the second air inlet pipe 352 respectively. The other ends of the first air inlet pipe 351 and the second air inlet pipe 352 are respectively connected to one end of the main air inlet pipe 350. The main air inlet pipe 350 is connected to the exhaust port of the air pump. The air pump is used to pump the external air flow into the main air inlet pipe 350.

[0060] A compression spring 550 is also installed between the limiting rod 561 and the limiting protrusion 562. The compression spring 550 is used to generate elastic force on the piston 520 to prevent it from moving toward the limiting protrusion 562. The piston 520 is sealed and axially slidably assembled with the switching inner cavity 511;

[0061] A limiting cylinder 530 is fixed on one end of the switching inner cavity 511 connected to the sealed exhaust pipe 332. The limiting cylinder 530 is provided with a through-gas groove 531, and the limiting cylinder 530 is used to limit the maximum displacement of the piston moving toward the limiting cylinder. One end of the limiting cylinder provided on the switching inner cavity 511 is also connected to the air nozzle 540. When the air nozzle 540 is opened, the switching inner cavity 511 can be connected to the external atmosphere;

[0062] Initial state ( Figure 4 state), the upper trumpet groove 522 is connected with one end of the air inlet pipe 341, and the other end of the air inlet pipe 341 enters the inner cover and is opposite to the top of the inner cover; the piston 520 is fitted or tightly against the end face of the limit cylinder under the elastic force of the compression spring 550, and the air nozzle 540 is in a closed state; the piston 520 is not fitted and assembled with the first air inlet pipe, the second air inlet pipe and the connection point of the switching inner cavity; the lower trumpet groove 521 is in a sealed state (not connected with the switching inner cavity) due to the sealing effect of the piston 520.

[0063] When in use, first open the protective cover 210, install the corresponding equipment on the orifice plate 140, and then install the protective cover. Start the air pump, the air pump pumps the air into the switching inner cavity, and then enters the inside of the sealing air ring 410 through the sealing air inlet pipe 331. The sealing air ring 410 expands when the air is taken in, so that the outer wall of the sealing air ring 410 is closely attached to the inner wall of the inner cover, thereby forming a fixing and sealing effect on the inner cover 211;

[0064] The gas entering the sealing gas ring 410 enters the switching inner cavity 511 on one side of the fixed limiting cylinder 530 through the sealing exhaust pipe 332, so that the gas pressure of this part rises, and then pushes the piston 520 to overcome the elastic force of the compression spring and move right, until the first intake pipe is not connected with the switching inner cavity (closed with the lower trumpet groove 521 or by the outer wall of the piston), at this time, the piston does not seal the connection between the sealed intake pipe and the switching inner cavity, the airflow continues to enter the sealing gas ring, and continues to push the piston to move right, until the limit rod and the limit protrusion are pressed tightly, at this time the piston moves to the right to the maximum displacement, and the lower trumpet groove is connected with the first intake pipe, the piston cuts off the seal at the connection between the sealed intake pipe and the switching inner cavity, the airflow can only enter the inner cover, and then spray to the top surface of the inner cover and disperse, and then flow downward, so that it is discharged from the exhaust pipe, so that good heat dissipation of the towing motor and servo motor in the inner cover can be achieved. The sealing gas ring is in a sealed state, which can keep the protective cover sealed and fixed.

[0065] After use, when the protective cover needs to be opened, just open the air nozzle to discharge the gas inside the switching inner cavity and the sealing air ring. At this time, the compression spring drives the piston to move to the left through elastic force until it fits with the limit cylinder here, and the sealing air ring will shrink due to the lack of internal air pressure, thereby releasing the seal and fixation of the protective cover.

[0066] Preferably, the minimum distance L1 from the upper trumpet groove 522 to the connection point between the sealed air inlet pipe 331 and the switching inner cavity 511 is greater than the minimum distance L2 from the lower trumpet groove 521 to the connection point between the first air inlet pipe 351 and the switching inner cavity. This design allows the first air inlet pipe 351 to be connected to the lower trumpet groove 521 before the piston closes the connection point between the sealed air inlet pipe 331 and the switching inner cavity 511, thereby avoiding the situation that when the connection point between the sealed air inlet pipe 331 and the switching inner cavity 511 is closed, the first air inlet pipe 351 is not yet connected to the lower trumpet groove 521, causing a malfunction. The purpose of designing the first air inlet pipe and the second air inlet pipe is to prevent the piston from moving rightward quickly and causing an impact. When the first air inlet pipe is cut off from being connected to the switching inner cavity and before the piston closes the connection point between the sealed air inlet pipe 331 and the switching inner cavity 511, the first air inlet pipe will gradually be connected to the lower trumpet groove, that is, the airflow entering the sealing air ring will gradually decrease, thereby forming a buffering effect.

[0067] See also Figure 5-Figure 7 , because in actual use, if the operating power of the servo motor is large, the resulting heat generation is also very large. At this time, if the inner cover is only blown by external airflow, this obviously cannot meet the heat dissipation requirements. The prior art mainly uses a servo motor that can be water-cooled, and then uses a water cooling system to dissipate the heat of the servo motor, such as the technical content disclosed in Chinese patents with publication numbers CN108803567A, CN103048621A, etc. However, this solution will bring about the design of the sealing structure and motor waterproof structure required for water cooling, and its cost is obviously high, and some towing motors do not have a water cooling structure, which results in insufficient heat dissipation of the towing motor. In response to this, the applicant proposed to directly use a water cooling system to cool the air and then blow it into the inner cover, thereby cooling the towing motor and servo motor as a whole.

[0068] The water cooling system comprises a water cooling box, the water cooling box comprises a box body 440, the interior of the box body 440 is an inner box 441, a spirally arranged water cooling pipe 310 is installed inside the inner box 441, both ends of the water cooling pipe 310 respectively pass through the box body 440 and are respectively connected to one end of the air intake joint 311 and the exhaust joint 312, the main air intake pipe 350 is cut into two sections and respectively connected in series to the air intake joint 311 and the exhaust joint 312, so that the water cooling pipe 310 and the main air intake pipe 350 are connected to form a complete air pipe;

[0069] The top of the inner box 441 is connected to the water inlet pipe 321, and the bottom is connected to the drain pipe 322. The water inlet pipe 321 is connected to the outlet of the cooler, the inlet of the cooler is connected to the outlet of the water pump, the inlet of the water pump is connected to the water in the water tank, and the inside of the water tank is also connected to the drain pipe 322. When in use, the water pump pumps water to the inner box and fills the inner box, so that the water cooling pipe 310 is flooded with water. At this time, the airflow passing through the inside of the water cooling pipe 310 can be water-cooled, thereby reducing the temperature of the airflow, and also can increase the cooling effect on the inside of the inner cover. This design can dissipate heat for the servo motor and the towing motor at the same time, and does not require waterproof structure design, so the cost is relatively low. When the water temperature in the inner box is high, the cooler can be turned on to reduce the water temperature, so that the water in the inner box can better exchange heat with the airflow in the water cooling pipe 310, that is, increase the heat dissipation effect.

[0070] Preferably, if a temperature sensor is installed in the inner box alone, the detection effect will be inaccurate due to the local temperature difference, and it will be impossible to accurately judge whether the cooler should be turned on. In this regard, the applicant installed a heat pipe 450 in the inner box, one end of the heat pipe 450 is open and the open end is assembled and fixed with the orifice plate 460, and the orifice plate 460 is provided with a number of through-holes 461, and the connecting holes 461 connect the inner box with the inside of the heat pipe 450, and the heat pipe 450 is also installed with a driving plug 230, and a memory spring 220 is installed between the driving plug 230 and the orifice plate 460, and the two ends of the memory spring 220 are respectively assembled and fixed with the driving plug 230 and the orifice plate 460;

[0071] The driving plug 230 is internally sealed and axially movable with the heat pipe 440, and the driving plug 230 is fixedly assembled with one end of the trigger rod 231, and the other end of the trigger rod 231 passes through the heat pipe 450 and faces the trigger end of the micro switch 610. The input end of the micro switch 610 is conductively connected to the output end of the constant current source, and the input end of the constant current source is conductively connected to the power supply, and the constant current source is used to convert the power supply into direct current with a stable voltage. In this embodiment, an AC-DC converter can be selected.

[0072] The output end of the micro switch 610 is conductively connected to the control end (coil) of the contactor, the input end of the contactor is conductively connected to the power supply, and the output end is conductively connected to the power connection end of the cooler. When the micro switch is triggered, the micro switch is closed, so that the contactor coil is energized and closed, and the cooler is powered on to operate, thereby cooling the water.

[0073] The memory spring 220 shortens below 30°C and lengthens at 50-60°C. When the water temperature in the inner box reaches 50-60°C, the memory spring 220 lengthens due to heat, thereby pushing the trigger rod to trigger the micro switch, and the micro switch closes, so that the contactor is closed, that is, the cooler works to cool the water. At this time, it is judged that the temperature inside the inner cover is too high. When the water temperature reaches below 30°C, the memory spring 220 shortens, so that the micro switch is disconnected, and the contactor is disconnected, and the cooler stops running, which also indicates that the temperature inside the inner cover is not high.

[0074] Preferably, the air inlet of the air pump is connected to the outlet of the electromagnetic reversing valve, the first inlet of the electromagnetic reversing valve is connected to the external atmosphere, the second inlet is connected to the exhaust pipe, the control end of the electromagnetic reversing valve is connected to the signal end of the real-time simulation controller, a temperature sensor 620 is installed in the inner cover, the signal end of the temperature sensor 620 is connected to the signal end of the PLC, and the temperature sensor is used to detect the temperature inside the inner cover. The electromagnetic reversing valve is used to selectively connect the first inlet, the second inlet and the outlet. In the initial state, the first inlet of the electromagnetic reversing valve is connected to the outlet of the electromagnetic reversing valve.

[0075] When the temperature detected by the temperature sensor reaches the threshold value (50°C), the PLC controls the electromagnetic reversing valve to connect the second inlet and outlet, so that the airflow inside the inner cover is circulated in a single cycle until the water temperature in the inner box reaches 50-60°C, and then the cooler is started to ensure the cooling effect inside the inner cover. When the temperature detected by the temperature sensor is lower than the threshold value, the electromagnetic reversing valve returns to its initial state.

[0076] The matters not described in detail in the present invention are all known technologies to those skilled in the art.

[0077] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A simulation teaching platform for DC servo motor control, characterized in that: include: A PC is installed with algorithm simulation software and host computer monitoring software, wherein the algorithm simulation software is used for performing algorithm simulation on the PC side, and the host computer monitoring software is used for realizing monitoring information or inputting control information through a screen; A real-time simulation controller is used to analyze the control signals and parameters corresponding to each physical device according to the algorithm simulated by the algorithm simulation software; DC drive control box, used to drive the servo motor to operate; The towing motor group is equipped with a servo motor and a towing motor, and the servo motor is driven by a DC drive control box; an encoder for detecting the rotation angle of the towing output shaft is installed in the towing motor, and the encoder is communicatively connected with a digital signal adapter board module in the DC drive control box, and the signal end of the digital signal adapter board module is communicatively connected with the signal end of the real-time simulation controller; The digital input and output and analog acquisition output of the built-in PLC in the DC drive control box are connected to the digital port and analog port of the real-time simulation controller, and the PC and the real-time simulation controller are connected via Ethernet communication; It also includes a protection module, which includes a base, which is fixed on the frame of the towing motor group, and a protection cover is fixed on the base, the inside of the protection cover is an inner cover, and the inner cover covers the outside of the servo motor and the towing motor; A support tube is fixed at the corresponding position of the base and the inner cover, a sealing gas ring is sleeved on the support tube, and the inner bottom of the support tube is connected to one end of the exhaust pipe, and the other end of the exhaust pipe is connected to the inner cover; The interior of the sealing air ring is connected to one end of the sealing intake pipe and the sealing exhaust pipe respectively, and the other ends of the sealing intake pipe and the sealing exhaust pipe are connected to the parts of the switching inner cavity located on both sides of the piston respectively. The switching inner cavity is arranged in the switching shell of the switching valve.

2. The DC servo motor control simulation teaching platform according to claim 1, characterized in that: The DC drive control box includes a 48V DC drive power supply, a 24V DC control power supply, a motor drive board, a terminal block and a digital signal adapter board module. The signal end of the PLC built into the DC drive control box is communicatively connected with the signal end of the real-time simulation controller.

3. The DC servo motor control simulation teaching platform according to claim 1, characterized in that: PC, software for teaching and researching DC servo motors, and also displays the basic electrical parameters and working conditions of the two motors on the platform through the display interface; real-time simulation controller, used to run the simulation model established by the PC, connected to the PC through Ethernet to exchange collected information and control instructions; The real-time simulation controller is connected to the DC drive control box via a signal line to exchange control signals, motor position information, and motor enable signals; the servo motor on the traction motor unit is connected to the DC drive control box via a power cable and is powered by the DC drive control box; the encoder of the traction motor is connected to the PLC signal terminal via a signal cable to provide encoder signals to the DC drive control box.

4. The DC servo motor control simulation teaching platform according to claim 1, characterized in that: The protective cover is made of transparent, fireproof and heat-insulating material.

5. The DC servo motor control simulation teaching platform according to claim 1, characterized in that: The piston is provided with an upper trumpet groove and a lower trumpet hole, the upper trumpet groove and the lower trumpet hole are connected to each other and penetrate the piston, and a limit rod is fixed on one end of the piston, a limit protrusion is fixed at the corresponding position of the switching inner cavity and the limit rod, and a first interval is provided between the limit rod and the limit protrusion; The switching inner cavity is connected to one end of the sealed intake pipe and is also connected to one end of the first intake pipe and the second intake pipe respectively. The other ends of the first intake pipe and the second intake pipe are connected to one end of the main intake pipe respectively. The main intake pipe is connected to the exhaust port of the air pump, and the air pump is used to pump external air into the main intake pipe. A compression spring is also installed between the limit rod and the limit protrusion, and the piston is sealed with the switching inner cavity and can be axially slidably assembled.

6. The DC servo motor control simulation teaching platform as claimed in claim 5, characterized in that: A limiting cylinder is fixed on one end of the switching inner cavity connected to the sealed exhaust pipe, and a through-gas groove is provided on the limiting cylinder. One end of the switching inner cavity provided with the limiting cylinder is also connected to the gas nozzle; In the initial state, the upper trumpet groove is connected with one end of the air inlet pipe, and the other end of the air inlet pipe enters the inner cover and faces the top of the inner cover; the piston is fitted or tightly attached to the end face of the limit cylinder under the elastic force of the compression spring, and the air nozzle is in a closed state; the piston is not fitted and assembled with the first air inlet pipe, the second air inlet pipe and the connection point of the switching inner cavity; the lower trumpet groove is in a sealed state due to the sealing effect of the piston.

7. The DC servo motor control simulation teaching platform according to claim 6, characterized in that: The minimum distance L1 from the upper trumpet groove to the connection point between the sealed air intake pipe and the switching inner cavity is greater than the minimum distance L2 from the lower trumpet groove to the connection point between the first air intake pipe and the switching inner cavity.

8. The DC servo motor control simulation teaching platform according to any one of claims 5 to 7, characterized in that: It also includes a water cooling system, the water cooling system includes a water cooling box, the water cooling box includes a box body, the inside of the box body is an inner box, a spirally arranged water cooling pipe is installed inside the inner box, both ends of the water cooling pipe respectively pass through the box body and are respectively connected to one end of the air intake joint and the exhaust joint, the main air intake pipe is cut into two sections and respectively connected in series to the air intake joint and the exhaust joint; The top of the inner box is connected to the water inlet pipe and the bottom is connected to the drain pipe. The water inlet pipe is connected to the inlet of the cooler, the inlet of the cooler is connected to the outlet of the water pump, the inlet of the water pump is connected to the water in the water tank, and the inside of the water tank is also connected to the drain pipe.

9. The DC servo motor control simulation teaching platform as claimed in claim 8, characterized in that: A heat conducting pipe is installed in the inner box, one end of the heat conducting pipe is open and the open end is assembled and fixed with the orifice plate, a plurality of through-holes are arranged on the orifice plate, and the communicating holes connect the inner box with the inside of the heat conducting pipe, a driving plug is also installed in the heat conducting pipe, a memory spring is installed between the driving plug and the orifice plate, and both ends of the memory spring are respectively assembled and fixed with the driving plug and the orifice plate; The driving plug is sealed inside the heat conducting tube and can be assembled axially upward, and the driving plug is assembled and fixed with one end of the trigger rod, and the other end of the trigger rod passes through the heat conducting tube and faces the trigger end of the micro switch, the access end of the micro switch is conductively connected to the output end of the constant current source, the access end of the constant current source is conductively connected to the power supply, and the constant current source is used to convert the power supply into direct current with a stable voltage; The output end of the micro switch is conductively connected to the control end of the contactor, the input end of the contactor is conductively connected to the power supply, and the output end is conductively connected to the power connection end of the cooler.

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