Numerical control machine tool state determination system using reconstruction current and determination method thereof

Abstract

The invention relates to a numerical control machine tool state judgment system utilizing reconstruction current and a judgment method thereof, and the numerical control machine tool state judgment system utilizing the reconstruction current comprises an active current system and a reconstruction current system. The active current system comprises a strong current output unit and a weak current output unit, and the reconstruction current system comprises a bus sampling unit, a strong current reconstruction unit, a weak current reconstruction unit and a current comparison unit. On the basis of a numerical control machine tool state judgment system utilizing reconstruction current, according to active output of an active current system, the reconstruction current system carries out electric signal sampling so as to calibrate and judge the working states of a strong current electric control module and a weak current electric control module of a numerical control machine tool, and all electric control modules of all numerical control machine tools are automatically detected in time and comprehensively. And stable operation of the numerically-controlled machine tool is ensured.

Description

Technical Field

[0001] The present application relates to the technical field of intelligent machine tools, and particularly to a numerical control machine tool state determination system and a determination method using reconstructed current. Background Art

[0002] A numerical control machine tool is short for a computer numerical control machine tool, which is an automated machine tool equipped with a program control system. This control system can logically process a program with control codes or other symbolic instructions, decode it, represent it in coded numbers, and input it into the numerical control device through an information carrier. After arithmetic processing, the numerical control device issues various control signals to control the actions of the machine tool, and automatically processes the parts according to the shape and size required by the drawing. It can be seen that a numerical control machine tool is a mechatronic product integrating multiple technologies such as machinery, electricity, hydraulics, pneumatics, microelectronics, and information.

[0003] It can be seen that a numerical control machine tool involves electrical control modules such as electricity, microelectronics, and information, and its working state is closely related to the electrical control modules. In practical applications, the working state of the data machine tool is determined by collecting electrical signals from the electrical control modules. However, since the electrical control modules of a numerical control machine tool involve both strong electricity and weak electricity at the same time, and the number of modules is complex, the testing method is relatively complex. Generally, engineers only test the key electrical control modules, resulting in the anomalies of other electrical control modules being difficult to detect, affecting the accuracy of the determination of the working state of the numerical control machine tool. Summary of the Invention

[0004] Based on the above analysis, in order to solve the problems that the electrical control modules of a numerical control machine tool involve both strong electricity and weak electricity at the same time, and the number of modules is complex, resulting in a relatively complex testing method, engineers generally only test the key electrical control modules, resulting in the anomalies of other electrical control modules being difficult to detect, affecting the accuracy of the determination of the working state of the numerical control machine tool, etc., the embodiments of the present invention provide a numerical control machine tool state determination system and a determination method using reconstructed current.

[0005] The embodiments of the present invention provide a numerical control machine tool state determination system using reconstructed current.

[0006] A numerical control machine tool state determination system using reconstructed current includes:

[0007] An active current system and a reconstructed current system;

[0008] Wherein, the active current system includes a strong electricity output unit and a weak electricity output unit;

[0009] The strong electricity output unit is used to output a first current to the strong electricity electrical control module in the numerical control machine tool;

[0010] The weak current output unit is configured to output a second current to the weak current electronic control module in the CNC machine tool;

[0011] The reconstructed current system includes a bus sampling unit, a strong current reconstruction unit, a weak current reconstruction unit, and a current comparison unit;

[0012] The bus sampling unit is configured to sample the electrical signal of the strong current electronic control module to obtain a third current, and is also configured to sample the electrical signal of the weak current electronic control module to obtain a fourth current;

[0013] The strong current reconstruction unit is configured to reconstruct a first calibrated current according to the third current;

[0014] The weak current reconstruction unit is configured to reconstruct a second calibrated current according to the fourth current;

[0015] The current comparison unit is configured to compare the first calibrated current and output a first state determination result of the strong current electronic control module according to the comparison result; and is also configured to compare the second calibrated current and output a second state determination result of the weak current electronic control module according to the comparison result.

[0016] The above CNC machine tool state determination system using reconstructed current includes an active current system and a reconstructed current system. The active current system includes a strong current output unit and a weak current output unit, and the reconstructed current system includes a bus sampling unit, a strong current reconstruction unit, a weak current reconstruction unit, and a current comparison unit. According to the active output of the active current system, the reconstructed current system performs electrical signal sampling to achieve calibration, determines the working states of the strong current electronic control module and the weak current electronic control module of the CNC machine tool, and automatically detects each electronic control module of each CNC machine tool in a timely and comprehensive manner to ensure the stable operation of the CNC machine tool.

[0017] In one embodiment, the active current system is built based on a PWM controller.

[0018] In one embodiment, the bus sampling unit includes:

[0019] A sampling bus;

[0020] A two-way selection switch circuit, one output terminal of which is connected to the sampling bus, and the two input terminals are respectively connected to the strong current electronic control module and the weak current electronic control module.

[0021] In one embodiment, the strong current reconstruction unit, the weak current reconstruction unit, and the current comparison unit are built based on the same processor.

[0022] A determination method for a CNC machine tool state determination system using reconstructed current includes the steps of:

[0023] Insert a first sampling sequence at the start of each segment of the first reference current to form the first current;

[0024] Insert a plurality of second sampling sequences in the setting window of the second reference current to form a second current; wherein, the sampling sequence is related to the fourth current;

[0025] Successively perform current sampling within the first sampling sequence to form a third current;

[0026] Perform current sampling within the first sampling sequence to form a third current; meanwhile, perform current sampling on the second sampling sequence to form a fourth current;

[0027] Reconstruct the third current according to the insertion timing of the first sampling sequence in the first reference current to obtain a first calibrated current;

[0028] Reconstruct the fourth current according to the insertion timing of the second sampling sequence in the second reference current to obtain a second calibrated current;

[0029] When the difference between the first calibrated current and the first set current is less than the first difference, determine that the working state of the high-voltage electric control module is normal, otherwise it is abnormal;

[0030] When the difference between the second calibrated current and the second set current is less than the second difference, determine that the working state of the low-voltage electric control module is normal, otherwise it is abnormal.

[0031] The determination method of the above-mentioned numerical control machine tool state determination system using reconstructed current is based on the numerical control machine tool state determination system using reconstructed current. According to the active output of the active current system, the reconstructed current system performs electrical signal sampling for calibration to determine the working states of the high-voltage electric control module and the low-voltage electric control module of the numerical control machine tool, so as to automatically detect each electric control module of each numerical control machine tool in a timely and comprehensive manner and ensure the stable operation of the numerical control machine tool.

[0032] In one embodiment, the process of inserting a first sampling sequence at the start of each segment of the first reference current to form the first current includes the steps of:

[0033] Insert two effective vectors at the start of each segment of the first reference current to form the first current.

[0034] In one embodiment, the process of inserting a plurality of second sampling sequences in the setting window of the second reference current to form a second current includes the steps of:

[0035] Insert two second sampling sequences in adjacent bands of the second reference current to form the second current.

[0036] In one embodiment, the process of reconstructing the third current according to the insertion timing of the first reference current in the first sampling sequence to obtain the first calibrated current includes the steps of:

[0037] Reconstruct the first two phases of the first calibrated current according to two consecutive first sampling sequences;

[0038] Calculate the third phase of the first calibrated current according to the first two phases of the first calibrated current.

[0039] In one embodiment, the process of reconstructing the fourth current according to the insertion timing of the second reference current in the second sampling sequence to obtain the second calibrated current includes the steps of:

[0040] Reconstruct the first two phases of the second calibrated current according to two consecutive second sampling sequences;

[0041] Calculate the third phase of the second calibrated current according to the first two phases of the second calibrated current.

[0042] In one embodiment, it further includes the steps of:

[0043] Perform a Clark transformation on the second calibrated current to obtain a first intermediate current value;

[0044] Perform a PARK transformation on the first intermediate current value to obtain a second intermediate current value

[0045] According to the angle step of the PARK transformation and the second intermediate current value, perform an inverse PARK transformation and an inverse Clark transformation in sequence to obtain the predicted value of the next carrier period of the second calibrated current. Description of the Drawings

[0046] Figure 1 It is a module structure diagram of a numerical control machine tool status determination system using reconstructed current in an embodiment;

[0047] Figure 2 It is a flowchart of the determination method of a numerical control machine tool status determination system using reconstructed current in an embodiment;

[0048] Figure 3 It is a flowchart of the determination method of a numerical control machine tool status determination system using reconstructed current in a preferred embodiment;

[0049] Figure 4 It is a timing diagram of the second calibrated current. Detailed Description of the Invention

[0050] To better understand the purpose, technical solution, and technical effects of the present invention, the following further explains the present invention in conjunction with the accompanying drawings and embodiments. At the same time, it is declared that the embodiments described below are only used to explain the present invention and are not used to limit the present invention.

[0051] An embodiment of the present invention provides a numerical control machine tool status determination system using reconstructed current.

[0052] Figure 1 The module structure diagram of the numerical control machine tool status determination system using reconstructed current in an embodiment is as Figure 1 shown. The numerical control machine tool status determination system using reconstructed current in an embodiment includes:

[0053] The active current system 10 and the reconstructed current system 11;

[0054] Among them, the active current system 10 includes a strong electricity output unit 100 and a weak electricity output unit 101;

[0055] The strong electricity output unit 100 is used to output a first current I1 to the strong electricity electronic control module 200 in the numerical control machine tool;

[0056] The weak electricity output unit 101 is used to output a second current I2 to the weak electricity electronic control module 201 in the numerical control machine tool;

[0057] The reconstructed current system 11 includes a bus sampling unit 110, a strong electricity reconstruction unit 111, a weak electricity reconstruction unit 112, and a current comparison unit 113;

[0058] The bus sampling unit 110 is used to sample the electrical signals of the strong electricity electronic control module 200 to obtain a third current I3, and is also used to sample the electrical signals of the weak electricity electronic control module 201 to obtain a fourth current I4;

[0059] The strong electricity reconstruction unit 111 is used to reconstruct a first calibration current IREF1 according to the third current I3;

[0060] The weak electricity reconstruction unit 112 is used to reconstruct a second calibration current IREF2 according to the fourth current I4;

[0061] The current comparison unit 113 is used to compare the first calibration current IREF1 and output a first status determination result of the strong electricity electronic control module 200 according to the comparison result; it is also used to compare the second calibration current IREF2 and output a second status determination result of the weak electricity electronic control module 201 according to the comparison result.

[0062] In this embodiment, the objects for determining the state of the CNC machine tool are the strong - electricity control module and the weak - electricity control module of the CNC machine tool. According to the uses of the modules, the strong - electricity control module and the weak - electricity control module can be pre - distinguished, and the strong - electricity output unit and the weak - electricity output unit are correspondingly allocated. Among them, the prerequisite for determining the states of the strong - electricity control module and the weak - electricity control module is that they are in the power - off state, and the strong - electricity output unit and the weak - electricity output unit power them on to provide a basis for the subsequent bus sampling unit.

[0063] Considering cost, through the single - bus sampling design of the bus sampling unit, electrical signal sampling is performed on the strong - electricity output unit and the weak - electricity output unit. At the same time, in terms of wire routing and module deployment, the impact on the original structure of the CNC machine tool and electrical signal interference are reduced to avoid affecting the machining accuracy of the original CNC machine tool.

[0064] In one embodiment, the active current system is built based on a PWM controller. The outputs of the strong - electricity output unit and the weak - electricity output unit are distinguished based on the modulation ratio of the PWM controller. The output higher than the set modulation ratio is the output of the weak - electricity output unit, and the output lower than the set modulation ratio is the output of the strong - electricity output unit. Among them, the set modulation ratio can be set by relevant personnel according to the equipment type of the CNC machine tool, and is not limited here.

[0065] In one embodiment, the bus sampling unit includes:

[0066] A sampling bus;

[0067] A two - way selection switch circuit, one output terminal of which is connected to the sampling bus, and the two input terminals are respectively connected to the strong - electricity control module and the weak - electricity control module.

[0068] Through the two - way selection switch circuit, the single - bus sampling design is realized. The two - way selection switch circuit can select controllable switch devices such as relays or switch chips.

[0069] Based on the CNC machine tool state determination system using reconstructed current in one embodiment, this embodiment also provides a determination method for the CNC machine tool state determination system using reconstructed current. Figure 2 For the flowchart of the determination method of the CNC machine tool state determination system using reconstructed current in one embodiment, as Figure 2 shown, it includes steps S10 to step S17:

[0070] S10, insert a first sampling sequence at the start section of each segment of the first reference current to form the first current;

[0071] S11, insert a plurality of second sampling sequences in the set window of the second reference current to form the second current; among them, the sampling sequence is related to the fourth current;

[0072] S12. Sequentially perform current sampling on the first sampling sequence to form a third current;

[0073] S13. Perform current sampling on the first sampling sequence to form a third current; meanwhile, perform current sampling on the second sampling sequence to form a fourth current;

[0074] S14. According to the insertion timing of the first reference current in the first sampling sequence, reconstruct the third current to obtain a first calibrated current;

[0075] S15. According to the insertion timing of the second reference current in the second sampling sequence, reconstruct the fourth current to obtain a second calibrated current;

[0076] S16. When the difference between the first calibrated current and the first set current is less than the first difference, determine that the working state of the high-power electronic control module is normal; otherwise, it is abnormal;

[0077] S17. When the difference between the second calibrated current and the second set current is less than the second difference, determine that the working state of the low-power electronic control module is normal; otherwise, it is abnormal.

[0078] The PWM controller uses multi-segment wave generation and outputs in the form of multiple sectors. Each sector corresponds to a segment of the first reference current. Insert the first sampling sequence at the start segment of each segment of the first reference current, and update the first reference current to form the first current.

[0079] Similarly, based on the multi-segment wave generation of the PWM controller, which outputs in the form of multiple sectors, the second reference current includes multiple sectors. According to the selection of the sector, determine the set window, and insert multiple second sampling sequences to form the second current.

[0080] In one preferred embodiment, Figure 3 It is a flowchart of the determination method of the numerical control machine tool state determination system using the reconstructed current in the preferred embodiment, as Figure 3 shown. The process of inserting the first sampling sequence at the start segment of each segment of the first reference current in step S10 to form the first current includes step S20:

[0081] S20. Insert two effective vectors at the start segment of each segment of the first reference current to form the first current.

[0082] After inserting the effective vector, the starting section of the first reference current includes null vectors and effective vectors. At this time, to ensure that the null vector is greater than zero, the basis is that the modulation ratio of the PWM controller is lower than the set modulation ratio. Otherwise, the null vector is less than zero, and the insertion of the effective vector will not work. The insertion of the effective vector can change the central symmetry of the first reference current, making the characteristics of the bus output after the first reference current passes through the strong electrical control module obvious. If the working state of the strong electrical control module is normal, this characteristic can be captured in the third current to reconstruct the first calibrated current.

[0083] However, when the modulation ratio of the PWM controller is greater than the set modulation ratio, it is applicable to the weak electrical control module but the corresponding null vector is less than 0. Therefore, the sampling sequence cannot be inserted at the starting section. Preferably, as Figure 3 shown, the process of inserting multiple second sampling sequences into the set window of the second reference current in step S11 to form the second current includes step S21:

[0084] S21, insert two second sampling sequences into adjacent bands of the second reference current respectively to form the second current.

[0085] Based on this, as Figure 3 shown, the process of reconstructing the third current according to the insertion timing of the first sampling sequence in the first reference current in step S14 to obtain the first calibrated current includes step S22 and step S23:

[0086] S22, reconstruct the first two phases of the first calibrated current according to two consecutive first sampling sequences;

[0087] S23, calculate the third phase of the first calibrated current according to the first two phases of the first calibrated current.

[0088] The process of step S15 reconstructing the fourth current according to the insertion timing of the second sampling sequence in the second reference current to obtain the second calibrated current includes step S24 and step S25:

[0089] S24, reconstruct the first two phases of the second calibrated current according to two consecutive second sampling sequences;

[0090] S25, calculate the third phase of the second calibrated current according to the first two phases of the second calibrated current.

[0091] In step S22 and step S23, the sampling of the U-phase current Iu is completed in the first first sampling sequence, and the sampling of the W-phase current Iw is completed in the second first sampling sequence; the V-phase current Iv = -Iu - Iw is calculated, and so on for the others. The first calibrated current includes the three-phase currents of the U-phase, W-phase, and V-phase.

[0092] In steps S24 and S25, as shown in the second calibration current timing diagram of Figure 4 , when the high modulation interval is large enough, in most cases, the second sampling sequences T1 and T2 are large enough. During the T1 segment, the U-phase current Iu is sampled by ADC1 as shown in Figure 4 ; during the T2 segment, the W-phase current Iw is sampled by ADC2 as shown in Figure 4 ; Iv = 0 - Iu - Iw is calculated. The second calibration current includes the three-phase currents of the U-phase, W-phase, and V-phase.

[0093] However, there is an exception in steps S24 and S25, that is, when the sector switching point θ is close to 0 or one of the second sampling sequences T1 and T2 is still very small. At this time, the sampling window will be very narrow and the three-phase current cannot be reconstructed. In this preferred embodiment, as shown in Figure 3 , it further includes steps S26, S27, and S28:

[0094] S26, perform Clark transformation on the second calibration current to obtain a first intermediate current value;

[0095] S27, perform PARK transformation on the first intermediate current value to obtain a second intermediate current value

[0096] S28, perform inverse PARK transformation and inverse Clark transformation in sequence according to the angle step of the PARK transformation and the second intermediate current value to obtain the predicted value of the next carrier period of the second calibration current.

[0097] Based on the clear second calibration currents Iu, Iw, and Iv, perform Clark transformation on the current to obtain the first intermediate current value i α , i β , then perform PARK transformation to obtain the second intermediate current value i d , i q . Among them, the angle θ 1 during PARK transformation is the integral of the output frequency during VF operation, and then the angle step Δθ is calculated according to the current output frequency and the period of the PWM controller, and the frequency integral θ 2 of the next PWM carrier is deduced as θ 1 +Δθ. According to the current i d , i q and θ 2 , perform inverse PARK transformation to obtain i α1 , i β1 ; then perform inverse Clark transformation to obtain the current predicted value I u1 , I v1 , I w1. In the next PWM cycle, if the calculated T 1 , T 2 If one of them is less than the minimum sampling window T min , one phase current cannot be reconstructed. In this case, the predicted current value calculated in the previous PWM can be assigned to the current sampling value. Based on this, the predicted value of the next carrier cycle of the second calibrated current is determined.

[0098] At this time, both the first calibrated current and the second calibrated current reconstructed have obvious characteristics, matching the working states of the corresponding high-power electric control module and low-power electric control module. The current comparison unit compares the first calibrated current and outputs the first state determination result of the high-power electric control module according to the comparison result, compares the second calibrated current, and outputs the second state determination result of the low-power electric control module according to the comparison result. By comparing the magnitudes of the first calibrated current and the second calibrated current, the working states of the high-power electric control module and the low-power electric control module can be determined. Among them, the current comparison unit can determine the comparison standard according to the experimental experience by comparing the standard values of the first calibrated current and the second calibrated current.

[0099] The state determination system and method of a numerically controlled machine tool using reconstructed current in this embodiment, the state determination system of a numerically controlled machine tool using reconstructed current, includes an active current system and a reconstructed current system. The active current system includes a high-power output unit and a low-power output unit, and the reconstructed current system includes a bus sampling unit, a high-power reconstruction unit, a low-power reconstruction unit, and a current comparison unit. Based on the state determination system of a numerically controlled machine tool using reconstructed current, according to the active output of the active current system, the reconstructed current system samples the electrical signal to achieve calibration, determines the working states of the high-power electric control module and the low-power electric control module of the numerically controlled machine tool, and automatically detects each electric control module of each numerically controlled machine tool in a timely and comprehensive manner to ensure the stable operation of the numerically controlled machine tool.

[0100] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

Claims

1. A CNC machine tool state determination system using reconstructed current, characterized in that: include: Active current systems and reconstructive current systems; Wherein, the active current system includes a strong current output unit and a weak current output unit; The high-voltage output unit is used to output a first current to a high-voltage electric control module in a CNC machine tool; The weak current output unit is used to output a second current to the weak current control module in the CNC machine tool; The reconstructed current system includes a bus sampling unit, a strong current reconstruction unit, a weak current reconstruction unit and a current comparison unit; The bus sampling unit is used to sample the electrical signal of the strong current electric control module to obtain the third current, and is also used to sample the electrical signal of the weak current electric control module to obtain the fourth current; The strong current reconstruction unit is used to reconstruct the first calibration current according to the third current; The weak current reconstruction unit is used to reconstruct a second calibration current according to the fourth current; The current comparison unit is used to compare the first calibration current and output the first state determination result of the high-current electric control module according to the comparison result; and is also used to compare the second calibration current and output the second state determination result of the low-current electric control module according to the comparison result.

2. The CNC machine tool state determination system using the reconstructed current according to claim 1, characterized in that: The active current system is built based on a PWM controller.

3. The CNC machine tool state determination system using reconstruction current according to claim 1, characterized in that: The bus sampling unit comprises: Sampling bus; A two-choice switch circuit has an output end connected to the sampling bus, and two input ends connected to the strong current control module and the weak current control module respectively. The sampling circuit samples the electrical signal of the sampling bus to obtain the third current or the fourth current.

4. The CNC machine tool state determination system using reconstruction current according to claim 1, characterized in that: The strong current reconstruction unit, the weak current reconstruction unit and the current comparison unit are constructed based on the same processor.

5. A determination method for a CNC machine tool state determination system using a reconstructed current, characterized in that: Includes steps: Inserting a first sampling sequence at the beginning of each first reference current to form a first current; Inserting a plurality of second sampling sequences in a setting window of a second reference current to form a second current; wherein the sampling sequence is related to the fourth current; sequentially sampling the current in the first sampling sequence to form a third current; Sampling the current in the first sampling sequence to form a third current; and sampling the current in the second sampling sequence to form a fourth current; Reconstructing the third current according to the insertion timing of the first sampling sequence in the first reference current to obtain a first calibration current; Reconstructing the fourth current according to the insertion timing of the second sampling sequence in the second reference current to obtain a second calibration current; When the difference between the first calibration current and the first set current is less than the first difference, it is determined that the working state of the high-voltage electric control module is normal, otherwise it is abnormal; When the difference between the second calibration current and the second set current is smaller than the second difference, it is determined that the working state of the weak current electric control module is normal, otherwise it is abnormal.

6. The determination method of the CNC machine tool state determination system using the reconstructed current according to claim 5, characterized in that: The process of inserting the first sampling sequence at the beginning of each first reference current to form the first current comprises the steps of: Two effective vectors are inserted into the beginning section of each first reference current to form the first current.

7. The determination method of the CNC machine tool state determination system using the reconstructed current according to claim 5, characterized in that: The process of inserting a plurality of second sampling sequences in the setting window of the second reference current to form the second current comprises the steps of: Two second sampling sequences are respectively inserted into adjacent bands of the second reference current to form a second current.

8. The determination method of the CNC machine tool state determination system using the reconstruction current according to claim 5, characterized in that: The process of reconstructing the third current according to the insertion timing of the first sampling sequence in the first reference current to obtain the first calibration current comprises the steps of: Reconstructing the first two phases of the first calibration current according to two consecutive first sampling sequences; A third phase of the first calibration current is calculated based on the first two phases of the first calibration current.

9. The determination method of the CNC machine tool state determination system using the reconstruction current according to claim 5, characterized in that: The process of reconstructing the fourth current according to the insertion timing of the second sampling sequence in the second reference current to obtain the second calibration current comprises the steps of: Reconstructing the first two phases of the second calibration current according to two consecutive second sampling sequences; A third phase of the second calibration current is calculated based on the first two phases of the second calibration current.

10. The determination method of the CNC machine tool state determination system using the reconstructed current according to claim 9, characterized in that: Also includes the steps: Performing Clark transformation on the second calibration current to obtain a first intermediate current value; Perform PARK transformation on the first intermediate current value to obtain a second intermediate current value An inverse PARK transformation and an inverse Clark transformation are performed in sequence according to the angular step amount of the PARK transformation and the second intermediate current value to obtain a predicted value of the next carrier cycle of the second calibration current.

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