Electric spark discharge pulse state identification, control system and method

Abstract

The present invention relates to the field of pulse state identification technology, and specifically to an electric spark discharge pulse state identification, control system and method. The electric spark discharge pulse state identification and control method comprises the following steps: obtaining a gap voltage and determining whether it is a rising edge voltage; comparing the gap voltage determined to be a rising edge voltage with a preset threshold voltage; when the gap voltage is the same as any one of the preset threshold voltages, the trigger state identifier is set to 1, and counting starts from the preset value A1; when any one of the stop counting conditions is met, counting is stopped, and the state identifier is cleared and the count value is returned to the preset value A1; the delay time between the two time points of starting counting and stopping counting is calculated; the delay time is determined and the determination result is output; and control is performed according to the determination result. The present invention quickly and accurately identifies short-circuit arc pulses and arc discharge pulses based on the pulse voltage threshold and time characteristics.

Description

Technical Field

[0001] The invention relates to the technical field of pulse state recognition, and in particular to an electric spark discharge pulse state recognition, control system and method. Background Art

[0002] In the field of EDM, adaptive control algorithm is one of the key technologies to ensure machining efficiency and precision. Traditional EDM adaptive control algorithm mainly relies on the gap voltage threshold judgment method to judge the quality of pulse discharge. This method sets a series of voltage thresholds and compares the gap voltage with these thresholds to distinguish the quality of pulse discharge. When the gap voltage is higher than a certain set upper threshold, the pulse is considered a good pulse, which means that the discharge process is stable and effective; when the gap voltage is lower than a certain set lower threshold, the pulse is considered a bad pulse, and servo adjustment or post-processing of the discharge pulse may be required.

[0003] However, this traditional method based on voltage threshold judgment has obvious limitations. It is mainly suitable for processing scenarios where the quality of power supply discharge is not high. In these scenarios, the discharge process is relatively stable, and short-circuit arcs and arc discharge phenomena are relatively rare, so the voltage threshold judgment method can meet the basic adaptive control needs. With the continuous improvement of modern manufacturing industry's requirements for processing accuracy and efficiency, the requirements for power supply discharge quality are also becoming increasingly stringent. Especially in some occasions that require high-precision and high-efficiency processing, such as precision mold manufacturing, aerospace parts processing and other fields, traditional methods can no longer meet the needs. These scenarios require the control system to be able to judge the quality of each discharge pulse in real time and accurately, and immediately process the bad pulses to ensure the continuity and stability of processing.

[0004] In addition, the traditional method has obvious shortcomings in dealing with short-circuit arc and arc discharge problems. Short-circuit arc and arc discharge are common phenomena in EDM, which can lead to problems such as insufficient discharge energy, low machining efficiency and reduced workpiece surface quality. However, since the gap voltage of short-circuit arc pulses and arc discharge pulses may still be within the voltage threshold range of traditional methods, these bad pulses are often not accurately identified and processed. The main reason is that the traditional method only relies on voltage thresholds for comparison and lacks comprehensive consideration of other discharge characteristic parameters. This method cannot clearly and quickly distinguish short-circuit arc pulses, arc discharge pulses and good discharge pulses, so it cannot effectively control the single pulse state. In the actual machining process, this may lead to the frequent occurrence of bad pulses, seriously affecting the machining quality and efficiency.

[0005] Therefore, how to solve the deficiency of the above-mentioned prior art that the short-circuit arc pulse, the arc discharge pulse and the good discharge pulse cannot be clearly and quickly distinguished has become the subject to be studied and solved by the present invention. Summary of the invention

[0006] The purpose of the present invention is to provide an electric spark discharge pulse state identification, control system and method.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is:

[0008] The electric spark discharge pulse state identification and control method comprises the following steps:

[0009] Obtain the gap voltage and determine whether it is a rising edge voltage;

[0010] Compare the gap voltage determined as a rising edge voltage with a preset threshold voltage; the preset threshold voltage includes a first preset threshold voltage corresponding to a short-circuit arc pulse threshold and a second preset threshold voltage corresponding to an arc discharge pulse threshold;

[0011] When the gap voltage determined to be a rising edge voltage is the same as any one of the preset threshold voltages, the trigger state identifier is set to 1, and counting starts from the preset value A1;

[0012] When any one of the counting stop conditions is met, counting is stopped, and the state identifier is cleared and the count value is returned to the preset value A1; the counting stop condition includes the gap voltage dropping to the preset threshold voltage reached during counting or the preset counting value; the preset value includes a first counting value B1 corresponding to the first preset threshold voltage and a second counting value B2 corresponding to the second preset threshold voltage;

[0013] Calculate the delay time between the start and stop time points of counting;

[0014] The delay time is judged and a judgment result is output; the judgment result includes a judgment as a short-circuit arc pulse, a judgment as an arc discharge pulse and a judgment as a normal pulse;

[0015] Control is performed according to the judgment result; the control content includes at least one of maintaining the pulse interval time and the movement equivalent, adjusting the pulse interval time, and adjusting the movement equivalent;

[0016] A1, B1 and B2 are all non-negative finite decimals or integers.

[0017] The premise of spark discharge pulse state identification is to obtain the gap voltage, and the key of this application is to identify the spark discharge pulse state by using the rising and falling edge time characteristics of different types of discharge pulses. Therefore, after obtaining the gap voltage, it is necessary to determine whether it is a rising edge voltage.

[0018] The main purpose of the present application is to identify short-circuit arc pulses and arc discharge pulses. Therefore, the preset threshold voltage needs to include a first preset threshold voltage corresponding to the short-circuit arc pulse threshold and a second preset threshold voltage corresponding to the arc discharge pulse threshold. The specific values ​​of the first preset threshold voltage and the second preset threshold voltage are pre-set based on processing experience, etc.

[0019] Determining the delay time is the key to utilizing the time characteristics of the rising and falling edges of different types of discharge pulses, and the determination of the delay time requires the use of the two time points of starting counting and stopping counting. For the time point of stopping counting, the preset threshold voltage reached when the gap voltage drops to the time of counting is usually used as the condition for stopping counting, but whether the gap voltage drops and the time required to drop to the preset threshold voltage reached when counting are difficult to determine. Therefore, a second stop counting condition is provided, that is, the count preset value is used as an auxiliary condition for determining whether to stop counting. By setting two stop counting conditions, counting stops when any stop counting condition is met, thereby adapting to complex actual processing conditions, avoiding the inability to determine the delay time or the long time required to determine the delay time, and ensuring the efficiency of electric spark discharge pulse state recognition.

[0020] Since different types of discharge pulses correspond to different delay times, after determining the delay time, it is possible to judge whether the discharge pulse is a short-circuit arc pulse or an arc discharge pulse, so that the pulse interval time and the movement equivalent can be controlled in time. This is suitable for application scenarios where the power supply discharge quality per unit time is high and it is necessary to timely judge and control the bad pulses such as short-circuit arc pulses and arc discharge pulses, such as in the scenario of electrospark machining to ensure the quality of electrospark machining.

[0021] A further technical solution is that when the gap voltage judged as a rising edge voltage is the same as at least two of the preset threshold voltages during the rising edge process, only the judgment result corresponding to the maximum preset threshold voltage is output, and the maximum preset threshold voltage is the preset threshold voltage with the largest value among the preset threshold voltages that are the same as the gap voltage at different time points.

[0022] Here, the first preset threshold voltage and the second preset threshold voltage are taken as examples to facilitate understanding. During the rising edge process, the gap voltage is first the same as the first preset threshold voltage and then the same as the second preset threshold voltage. When the method in this embodiment is not adopted, two judgment processes need to be completed and two judgment results are output, and the number of operations increases. After the method in this embodiment is adopted, the judgment is started when the gap voltage is the same as the first preset threshold voltage. Before outputting the judgment result, if the gap voltage is the same as the second preset threshold voltage, the output of the judgment result is stopped. At this time, the judgment process is completed only once, reducing the number of operations and thus reducing the system burden. The subsequent third preset threshold voltage and fourth preset threshold voltage refer to this process.

[0023] Optionally, after the trigger state identifier is set to 1, if no new state identifier is triggered to be set to 1 within a predetermined time period, counting starts from the preset value A1. When the first state identifier is set to 1, counting does not start from the preset value A1 immediately, and counting starts when the second state identifier is not triggered to be set to 1 within a predetermined time period; when the second state identifier is triggered to be set to 1, if the third state identifier is not triggered to be set to 1 within a predetermined time period, counting starts from the preset value A1. By setting a predetermined time period as the waiting time, the system computing burden can be further reduced. It should be noted that this setting is more suitable for situations where it is not necessary to identify short-circuit arc pulses and arc discharge pulses in a very short time or where the number of short-circuit arc pulses and arc discharge pulses occurs very rarely.

[0024] According to a further technical solution, when the gap voltage count reaches the first preset threshold voltage, the delay time is recorded as Δ1;

[0025] When the gap voltage count reaches the second preset threshold voltage, the delay time is recorded as Δ2;

[0026] The step of judging the delay time includes a step of judging Δ1 and a step of judging Δ2;

[0027] The step of judging Δ1 comprises:

[0028] Compare Δ1 with a preset value A2;

[0029] When Δ1<preset value A2, it is judged as a short-circuit arc pulse;

[0030] When Δ1>preset value A2, it is judged as a normal pulse;

[0031] The step of judging Δ2 comprises:

[0032] Compare Δ2 with a preset value A3;

[0033] When Δ2<preset value A3, it is judged as an arc discharge pulse;

[0034] When Δ2>preset value A3, it is judged as a normal pulse;

[0035] A2 and A3 are both non-negative finite decimals or integers.

[0036] Taking the example of judging whether it is a short-circuit arc pulse, the key step is to determine the delay time Δ1, and then compare Δ1 with the preset value A2. Since there are fewer numerical values ​​or data involved and fewer calculation steps, the pulse state can be quickly identified, and then the pulse can be quickly processed. It is suitable for application scenarios with high requirements on the power supply discharge quality per unit time, and it is necessary to timely judge the bad pulses such as short-circuit arc pulses and arc discharge pulses and control and process them in time.

[0037] In a further technical solution, the first count value B1= ; The preset value A2= ; The second count value B2= ; The preset value A3= ;

[0038] Both n1 and n2 are positive integers;

[0039] The ON is the discharge time set by the single pulse T;

[0040] The z is the time required for one count.

[0041] A further technical solution is to maintain the pulse interval time and movement equivalent when judging it as a normal pulse;

[0042] When it is judged as a short-circuit arc pulse, adjust the pulse interval time;

[0043] When it is determined to be an arc discharge pulse, the pulse interval time and movement equivalent are adjusted.

[0044] Taking the control of arc discharge pulse as an example, at this time, the pulse interval time and the movement equivalent need to be adjusted at the same time. The specific effects are as follows: the triggering frequency of arc discharge is reduced by adjusting (generally increasing) the pulse interval time, and the movement equivalent is adjusted to ensure control accuracy and stability.

[0045] Different control processing measures are taken according to different types of pulse signals to ensure the stability and accuracy of the pulse control system, thereby meeting practical application needs.

[0046] According to a further technical solution, the step of controlling according to the judgment result includes the step of controlling according to the judgment result as a normal pulse, the step of controlling according to the judgment result as a short-circuit arc pulse and the step of controlling according to the judgment result as an arc discharge pulse;

[0047] The step of determining a normal pulse and performing control comprises:

[0048] Maintain pulse interval time and movement equivalent;

[0049] The step of determining that the short-circuit arc pulse is controlled comprises:

[0050] Set the next pulse interval to be equal to the previous pulse interval multiplied by AN1;

[0051] The AN1 is initially set to 1;

[0052] When it is determined to be a short-circuit arc pulse, the AN1 increases by a preset value A4;

[0053] When the pulse is judged as normal for d consecutive times, the preset value A5 is subtracted from AN1;

[0054] When AN1=e and it is judged as a short-circuit arc pulse for f consecutive times, the conduction time of the current pulse is immediately ended and the timing cycle of the next pulse is started, and AN1 is reset to 1 at the same time;

[0055] The step of determining that an arc discharge pulse is to be controlled comprises:

[0056] Set the next pulse interval to be equal to the previous pulse interval multiplied by AN2;

[0057] The AN2 is initially set to 1;

[0058] When it is judged to be an arc discharge pulse, the AN2 increases by a preset value A6;

[0059] When the pulse is judged as normal for g times in a row, the preset value A7 is subtracted from AN2;

[0060] When AN2=h and it is judged as an arc discharge pulse for i consecutive times, the conduction time of the current pulse is immediately ended and the timing cycle of the next pulse is started. At the same time, AN2 is reset to 1 and j moving equivalents are retreated;

[0061] A4, A5, A6, A7, e and h are all non-negative finite decimals or integers;

[0062] The d, the f, the g, the i, and the j are all non-negative integers.

[0063] After it is judged as an arc discharge pulse, the control steps are the most complicated. It is taken as an example to illustrate as follows: First, within a certain range, after it is judged as an arc discharge pulse, the interval time of the next pulse (hereinafter referred to as the interval time) is extended. The more times it is judged as an arc discharge pulse, the longer the interval time; secondly, here g is set to 1 for illustration. When it is judged as a normal pulse, the interval time is shortened to speed up the response speed of the system; after exceeding the above certain range, that is, when it is judged as an arc discharge pulse more times, the conduction time of the current pulse is immediately ended and the timing cycle of the next pulse is started, and the mobile equivalent is backed off. This setting provides an emergency processing mechanism for protecting the system or equipment.

[0064] There are several points that need to be emphasized and supplemented for the control steps of the above-mentioned arc discharge pulses, as follows: First, the interval time of the next pulse is continuously increasing within a certain range, rather than remaining unchanged, so that it can be continuously adjusted according to the number of recognition times of the arc discharge pulse to continuously reduce the frequency of occurrence of the arc discharge pulse; second, g is set to be greater than or equal to 2, at this time, the probability of an increase in the frequency of occurrence of the arc discharge pulse due to misjudgment can be reduced; third, i is set to be greater than or equal to 3 to improve the accuracy of the judgment result.

[0065] Here, the above-set g and i are further explained using the EDM process. If both g and i are greater than 1, the accuracy of judgment can be improved, the equipment and workpiece can be protected, the machining efficiency can be optimized, and the machining accuracy can be improved. This helps to achieve the stability and controllability of the machining process, and is suitable for machining areas that require high precision and stability. Specifically, to explain the protection of equipment and workpieces, if the interval time is immediately shortened after a single judgment, heat accumulation may occur due to excessive discharge, thereby damaging the electrode and workpiece. If the conduction time of the current pulse is terminated after a single judgment, excessive arc discharge may occur, causing damage to the equipment and workpiece.

[0066] Optionally, e is equal to h, and f is greater than i. At this time, the specific control mechanisms of the short-circuit arc pulse and the arc discharge pulse are relatively similar, and the difference mainly lies in f and i. f is greater than i, which conforms to the actual situation that the short-circuit arc pulse usually causes greater damage to equipment and workpieces, and requires more stringent judgment conditions to ensure that the pulse conduction time is terminated in time to avoid damage.

[0067] In a further technical solution, the preset threshold voltage further includes a third preset threshold voltage corresponding to a good discharge pulse threshold;

[0068] The judgment result also includes judging as a good discharge pulse;

[0069] When the gap voltage count reaches the third preset threshold voltage, the delay time is recorded as Δ3.

[0070] The present application focuses on identifying short-circuit arc pulses and arc discharge pulses, but is also used to identify good discharge pulses.

[0071] In a further technical solution, the step of determining the delay time further comprises the step of determining Δ3;

[0072] The step of judging Δ3 comprises:

[0073] Compare Δ3 with the preset value A8;

[0074] When Δ3<preset value A8, it is determined to be a good discharge pulse in the first state;

[0075] When the preset value A8<Δ3<preset value A9, it is determined to be a good discharge pulse in the second state;

[0076] Both A8 and A9 are non-negative finite decimals or integers.

[0077] Taking judging whether it is a good discharge pulse in the second state as an example, the key step is to determine the delay time Δ3, and then compare Δ3 with the preset value A8 and the preset value A9. Since fewer numerical values ​​or data are involved and fewer calculation steps are involved, the pulse state can be quickly identified, and then the pulse can be quickly processed. It is suitable for application scenarios with high requirements on the discharge quality of the power supply per unit time, and it is necessary to timely judge the good discharge pulses in different states and control the processing in time.

[0078] It should be emphasized that the good discharge pulse is divided into a good discharge pulse in a first state and a good discharge pulse in a second state according to the state. The present application can not only identify the good discharge pulse but also distinguish the good discharge pulse and then perform targeted control processing.

[0079] A further technical solution is to maintain the pulse interval time and the movement equivalent when it is determined to be a good discharge pulse in the first state;

[0080] When it is determined to be a good discharge pulse in the second state, k movement equivalents are fed.

[0081] The k is a non-negative integer.

[0082] In a further technical solution, the preset threshold voltage further includes a fourth preset threshold voltage corresponding to a no-load pulse threshold;

[0083] When the gap voltage count reaches the fourth preset threshold voltage, it is determined to be a no-load pulse, and the pulse interval time and the movement equivalent are maintained.

[0084] Although the good discharge pulse in the second state is a good discharge pulse, the active discharge time is short, and the servo system automatically feeds k movement equivalents.

[0085] Also provided herein is an electric spark discharge pulse state identification and control system, which is used in the electric spark discharge pulse state identification and control method in any of the above embodiments, wherein the electric spark discharge pulse state identification and control system comprises a system microcontroller, a power amplifier, an electric discharge machining circuit, a gap detection circuit, a sampling voltage conditioning circuit, and a servo feed control circuit;

[0086] The first output terminal of the system microcontroller is connected to the input terminal of the servo feed control loop; the output terminal of the servo feed control loop is connected to the first input terminal of the gap detection loop;

[0087] The second output terminal of the system microcontroller is connected to the input terminal of the power amplifier; the output terminal of the power amplifier is connected to the input terminal of the electrical discharge machining circuit; the output terminal of the electrical discharge machining circuit is connected to the second input terminal of the gap detection circuit;

[0088] The output end of the gap detection loop is connected to the input end of the sampling voltage conditioning circuit; the output end of the sampling voltage conditioning circuit is connected to the input end of the system microcontroller;

[0089] The system microcontroller is used to generate a predetermined pulse and input the predetermined pulse into the power amplifier; the power amplifier is used to amplify the predetermined pulse to form an amplified pulse, and input the amplified pulse into the discharge machining circuit; the discharge machining circuit is driven by the amplified pulse to perform pulse-type discharge; the gap detection circuit is used to detect the gap voltage between the workpiece and the electrode in the discharge machining circuit and input the gap voltage into the sampling voltage conditioning circuit; the sampling voltage conditioning circuit is used to condition the gap voltage into a low-voltage signal allowed to be input by the external IO input port of the system microcontroller; the system microcontroller makes a judgment based on the low-voltage signal, and can adjust the pulse interval time and the movement equivalent through the power amplifier and the servo feed control circuit according to the judgment result.

[0090] The terms “first”, “second”, etc. used in this document do not specifically refer to an order or sequence, nor are they used to limit the present case. They are only used to distinguish components or operations described with the same technical terms.

[0091] As used herein, “connected” or “positioned” may refer to two or more components or devices being in direct physical contact with each other, or being in indirect physical contact with each other, or may refer to two or more components or devices operating or moving with each other.

[0092] The terms “include,” “including,” “have,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0093] The terms used in this document generally have the ordinary meaning of each term used in this field, in the context of the case and in the specific context, unless otherwise noted. Certain terms used to describe the present invention will be discussed below or elsewhere in this specification to provide additional guidance to those skilled in the art in describing the present invention.

[0094] The working principle and advantages of the present invention are as follows: The present invention is based on the pulse voltage threshold and time characteristics. During the identification process, the gap voltage is first obtained and it is determined whether it is a rising edge voltage; the gap voltage determined to be a rising edge voltage is compared with the preset threshold voltage; when the gap voltage is the same as any one of the preset threshold voltages, the trigger state identifier is set to 1, and counting starts from the preset value A1; when any one of the stop counting conditions is met, the counting is stopped, and the state identifier is cleared and the count value is returned to the preset value A1; the delay time between the two time points of starting counting and stopping counting is calculated; the delay time is judged and the judgment result is output; and control is performed according to the judgment result. In addition to utilizing the voltage thresholds of different types of discharge pulses, this application also utilizes the time characteristics of the upper and lower edges of different types of discharge pulses to achieve rapid and accurate identification of short-circuit arc pulses and arc discharge pulses, and timely control of the pulse interval time and movement equivalent. It is suitable for application scenarios with high requirements for power supply discharge quality per unit time, and it is necessary to timely judge and control the processing of bad pulses such as short-circuit arc pulses and arc discharge pulses, such as ensuring the quality of electric spark machining in the scenario of electric spark machining, and avoiding the frequent occurrence of bad pulses in the actual machining process. At the same time, by setting two stop counting conditions, the counting is stopped when any stop counting condition is met, thereby adapting to complex actual machining conditions, avoiding the inability to determine the delay time or the long time required to determine the delay time, and ensuring the efficiency of electric spark discharge pulse state recognition. BRIEF DESCRIPTION OF THE DRAWINGS

[0095] Attached Figure 1 Schematic diagram of threshold voltages of different types of discharge pulses according to an embodiment of the present invention;

[0096] Attached Figure 2 The figure is a flow chart of the spark discharge pulse state identification and control system according to an embodiment of the present invention.

[0097] In the above figures: BV1=20V, indicating the short-circuit arc discharge pulse threshold; BV2=40V, indicating the arc discharge pulse threshold; BV3=60V, indicating the good discharge pulse threshold; BV4=80V, indicating the no-load discharge pulse. DETAILED DESCRIPTION

[0098] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0099] Embodiment: The present invention will be clearly described below with diagrams and detailed descriptions. After understanding the embodiments of the present invention, any person skilled in the art can make changes and modifications based on the techniques taught by the present invention without departing from the spirit and scope of the present invention.

[0100] The terms used herein are only for describing specific embodiments and are not intended to be limiting of the present invention. Singular forms such as "a", "this", "here", "this" and "the" as used herein also include plural forms.

[0101] See attached Figure 1 -Attached Figure 2 , the spark discharge pulse state identification and control method comprises the following steps:

[0102] Obtain the gap voltage and determine whether it is a rising edge voltage;

[0103] Compare the gap voltage determined as a rising edge voltage with a preset threshold voltage; the preset threshold voltage at least includes a first preset threshold voltage corresponding to a short-circuit arc pulse threshold and a second preset threshold voltage corresponding to an arc discharge pulse threshold;

[0104] When the gap voltage determined to be a rising edge voltage is the same as any one of the preset threshold voltages, the trigger state identifier is set to 1, and counting starts from the preset value A1;

[0105] When any one of the counting stop conditions is met, counting is stopped, the state identifier is cleared and the count value is returned to the preset value A1; the counting stop condition includes the gap voltage dropping to the preset threshold voltage reached during counting or the preset counting value; the preset value includes at least a first counting value B1 corresponding to the first preset threshold voltage and a second counting value B2 corresponding to the second preset threshold voltage;

[0106] Calculate the delay time between the start and stop time points of counting;

[0107] The delay time is judged and a judgment result is output; the judgment result includes a judgment as a short-circuit arc pulse, a judgment as an arc discharge pulse and a judgment as a normal pulse;

[0108] Control is performed according to the judgment result; the control content includes at least one of maintaining the pulse interval time and the movement equivalent, adjusting the pulse interval time, and adjusting the movement equivalent;

[0109] A1, B1 and B2 are all non-negative finite decimals or integers.

[0110] The premise of spark discharge pulse state identification is to obtain the gap voltage, and the key of this application is to identify the spark discharge pulse state by using the rising and falling edge time characteristics of different types of discharge pulses. Therefore, after obtaining the gap voltage, it is necessary to determine whether it is a rising edge voltage.

[0111] The main purpose of the present application is to identify short-circuit arc pulses and arc discharge pulses. Therefore, the preset threshold voltage needs to include a first preset threshold voltage corresponding to the short-circuit arc pulse threshold and a second preset threshold voltage corresponding to the arc discharge pulse threshold. The specific values ​​of the first preset threshold voltage and the second preset threshold voltage are pre-set based on processing experience, etc.

[0112] Determining the delay time is the key to utilizing the time characteristics of the rising and falling edges of different types of discharge pulses, and the determination of the delay time requires the use of the two time points of starting counting and stopping counting. For the time point of stopping counting, the preset threshold voltage reached when the gap voltage drops to the time of counting is usually used as the condition for stopping counting, but whether the gap voltage drops and the time required to drop to the preset threshold voltage reached when counting are difficult to determine. Therefore, a second stop counting condition is provided, that is, the count preset value is used as an auxiliary condition for determining whether to stop counting. By setting two stop counting conditions, counting stops when any stop counting condition is met, thereby adapting to complex actual processing conditions, avoiding the inability to determine the delay time or the long time required to determine the delay time, and ensuring the efficiency of electric spark discharge pulse state recognition.

[0113] Since different types of discharge pulses correspond to different delay times, after determining the delay time, it is possible to judge whether the discharge pulse is a short-circuit arc pulse or an arc discharge pulse, so that the pulse interval time and the movement equivalent can be controlled in time. This is suitable for application scenarios where the power supply discharge quality per unit time is high and it is necessary to timely judge and control the bad pulses such as short-circuit arc pulses and arc discharge pulses, such as to ensure the quality of electrospark machining in the scenario of electrospark machining.

[0114] It should be noted that when any one of the counting stop conditions is met, counting is stopped, the state identifier is cleared and the count value is returned to the preset value A1. Both the clearing setting and the return setting are for realizing the continuous recognition of the discharge pulse state.

[0115] It should also be noted that after the discharge pulse state is identified, control must be carried out in a timely manner. The control content includes maintaining the pulse interval time and the moving equivalent, adjusting the pulse interval time, and adjusting at least one of the moving equivalent. The control method corresponding to different pulse states is a pre-set content, but in the specific implementation, it may have a dynamic adjustment process. For example, the adjustment amount of the moving equivalent can be dynamically adjusted.

[0116] Optionally, the preset value A1 is initially set to zero.

[0117] In this embodiment, when the gap voltage judged as the rising edge voltage is the same as at least two of the preset threshold voltages at different time points in the rising edge process, only the judgment result corresponding to the maximum preset threshold voltage is output, and the maximum preset threshold voltage is the preset threshold voltage with the largest value among the preset threshold voltages that are the same as the gap voltage.

[0118] See also Figure 1 Here, the first preset threshold voltage (BV1=20V) and the second preset threshold voltage (BV2=40V) are used as examples to help understanding. During the rising edge process, the gap voltage is first the same as the first preset threshold voltage and then the same as the second preset threshold voltage. When the method in this embodiment is not adopted, two judgment processes need to be completed and two judgment results are output, and the number of operations increases. After the method in this embodiment is adopted, when the gap voltage is the same as the first preset threshold voltage, the judgment begins. Before outputting the judgment result, if the gap voltage is the same as the second preset threshold voltage, the judgment result is stopped from being output, and the judgment result corresponding to the second preset threshold voltage is output. At this time, only one judgment is completed, which reduces the number of operations and thus reduces the system burden. The subsequent third preset threshold voltage and fourth preset threshold voltage refer to this process.

[0119] For further understanding, additional explanation is continued here. In this embodiment, the trigger priority of the state identifier is actually set to be higher than the priority of the counting process and the judgment process. Different preset threshold voltages correspond to different state identifiers. When the latter state identifier is triggered, the counting process and the judgment process previously being executed need to be stopped.

[0120] It should be added that, since the target is a preset threshold voltage, the situation where the values ​​are the same can be avoided.

[0121] It should be emphasized that, also taking the first preset threshold voltage and the second preset threshold voltage as an example, the judgment is started when the gap voltage is the same as the first preset threshold voltage. No waiting time is set here to avoid the increase in the time for identifying the short-circuit arc pulse due to failure to make a timely judgment. The short-circuit arc pulse and the arc discharge pulse are identified in time to avoid affecting the processing process.

[0122] Optionally, after the trigger state identifier is set to 1, if no new state identifier is triggered to be set to 1 within a predetermined time period, counting starts from the preset value A1. When the first state identifier is set to 1, counting does not start from the preset value A1 immediately, and counting starts when the second state identifier is not triggered to be set to 1 within a predetermined time period; when the second state identifier is triggered to be set to 1, if the third state identifier is not triggered to be set to 1 within a predetermined time period, counting starts from the preset value A1. By setting a predetermined time period as the waiting time, the system computing burden can be further reduced. It should be noted that this setting is more suitable for situations where it is not necessary to identify short-circuit arc pulses and arc discharge pulses in a very short time or where the number of short-circuit arc pulses and arc discharge pulses occurs very rarely.

[0123] In this embodiment, when the gap voltage count reaches the first preset threshold voltage, the delay time is recorded as Δ1;

[0124] When the gap voltage count reaches the second preset threshold voltage, the delay time is recorded as Δ2;

[0125] The step of judging the delay time includes a step of judging Δ1 and a step of judging Δ2;

[0126] The step of judging Δ1 comprises:

[0127] Compare Δ1 with a preset value A2;

[0128] When Δ1<preset value A2, it is judged as a short-circuit arc pulse;

[0129] When Δ1>preset value A2, it is judged as a normal pulse;

[0130] The step of judging Δ2 comprises:

[0131] Compare Δ2 with a preset value A3;

[0132] When Δ2<preset value A3, it is judged as an arc discharge pulse;

[0133] When Δ2>preset value A3, it is judged as a normal pulse;

[0134] A2 and A3 are both non-negative finite decimals or integers.

[0135] When the gap voltage count reaches the first preset threshold voltage, the delay time is recorded as Δ1, and then the step of judging Δ1 is directly adopted, that is, different judgment steps are adopted corresponding to different preset threshold voltages, or in other words, the judgment steps are the same or similar as a whole, but there are some differences in the specific contents.

[0136] The preset value A2 and the preset value A3 are both determined based on experience in processing and testing, so as to ensure the accuracy of the measurement results.

[0137] Taking the example of judging whether it is a short-circuit arc pulse, the key step is to determine the delay time Δ1, and then compare Δ1 with the preset value A2. Since there are fewer numerical values ​​or data involved and fewer calculation steps, the pulse state can be quickly identified, and then the pulse can be quickly processed. It is suitable for application scenarios with high requirements on the power supply discharge quality per unit time, and it is necessary to timely judge the bad pulses such as short-circuit arc pulses and arc discharge pulses and control and process them in time.

[0138] In this embodiment, the first count value B1= ; The preset value A2= ; The second count value B2= ; The preset value A3= ;

[0139] Both n1 and n2 are positive integers;

[0140] The ON is the discharge time set by the single pulse T;

[0141] The z is the time required for one count.

[0142] Here is a specific method for determining Δ1 for reference, as follows: the first preset threshold voltage is set to 20V. When the gap voltage (set to BV) rises to 20V, the trigger state identifier (set to CNTFLAG1) is set to 1, and the internal register (set to CNT1) starts rising edge counting. When the gap voltage drops to 20V or when CNT1 counts to (In the formula, multiply by One quarter of the counting time is taken as the trigger signal for the software reset of CNTFLAG1. ON -1 is the discharge time set by the single pulse T inside the controller minus the margin time estimated by the line delay time, 1µS; multiplied by 1000, it means changing the original µS to nanoseconds; because the crystal oscillator is 50MHZ, each CNT count is 20 nanoseconds, so it needs to be divided by 20), CNT1 stops counting and CNTFLAG1 is reset to 0. The delay time from the gap voltage rising from 20V to the CNT1 stopping counting is recorded as Δ1.

[0143] Here, a specific method for determining Δ2 is also given as a reference, as follows: the second preset threshold voltage is set to 40V. When the gap voltage (set to BV) rises to 40V, the trigger state identifier (set to CNTFLAG2) is set to 1, and the internal register (set to CNT2) starts rising edge counting. When the gap voltage drops to 40V or when CNT2 counts to (In the formula, multiply by One fifth of the counting time is taken as the trigger signal for the software reset of CNTFLAG2. ON -1 is the discharge time set by the single pulse T inside the controller minus the margin time estimated by the line delay time, 1µS; multiplied by 1000, it means changing the original µS to nanoseconds; because the crystal oscillator is 50MHZ, each CNT count is 20 nanoseconds, so it needs to be divided by 20), CNT2 stops counting and CNTFLAG2 is reset to 0. The delay time from the gap voltage rising from 40V to the CNT2 stopping counting is recorded as Δ2.

[0144] In this embodiment, when it is determined to be a normal pulse, the pulse interval time and the movement equivalent are maintained;

[0145] When it is judged as a short-circuit arc pulse, adjust the pulse interval time;

[0146] When it is determined to be an arc discharge pulse, the pulse interval time and movement equivalent are adjusted.

[0147] After identifying the pulse state, targeted control is required. The control content includes at least one of maintaining the pulse interval time and the movement equivalent, adjusting the pulse interval time, and adjusting the movement equivalent. Specifically, when it is judged as a normal pulse, the pulse interval time and the movement equivalent are maintained; when it is judged as a short-circuit arc pulse, the pulse interval time is adjusted; when it is judged as an arc discharge pulse, the pulse interval time and the movement equivalent are adjusted.

[0148] Taking the control of arc discharge pulse as an example, at this time, the pulse interval time and the movement equivalent need to be adjusted at the same time. The specific effects are as follows: the triggering frequency of arc discharge is reduced by adjusting (generally increasing) the pulse interval time, and the movement equivalent is adjusted to ensure control accuracy and stability.

[0149] Different control processing measures are taken according to different types of pulse signals to ensure the stability and accuracy of the pulse control system, thereby meeting practical application needs.

[0150] In this embodiment, the step of controlling according to the judgment result includes the step of controlling according to the judgment result as a normal pulse, the step of controlling according to the judgment result as a short-circuit arc pulse, and the step of controlling according to the judgment result as an arc discharge pulse;

[0151] The step of determining a normal pulse and performing control comprises:

[0152] Maintain pulse interval time and movement equivalent;

[0153] The step of determining that the short-circuit arc pulse is controlled comprises:

[0154] Set the next pulse interval to be equal to the previous pulse interval multiplied by AN1;

[0155] The AN1 is initially set to 1;

[0156] When it is determined to be a short-circuit arc pulse, the AN1 increases by a preset value A4;

[0157] When the pulse is judged as normal for d consecutive times, the preset value A5 is subtracted from AN1;

[0158] When AN1=e and it is judged as a short-circuit arc pulse for f consecutive times, the conduction time of the current pulse is immediately ended and the timing cycle of the next pulse is started, and AN1 is reset to 1 at the same time;

[0159] The step of determining that an arc discharge pulse is to be controlled comprises:

[0160] Set the next pulse interval to be equal to the previous pulse interval multiplied by AN2;

[0161] The AN2 is initially set to 1;

[0162] When it is judged to be an arc discharge pulse, the AN2 increases by a preset value A6;

[0163] When the pulse is judged as normal for g times in a row, the preset value A7 is subtracted from AN2;

[0164] When AN2=h and it is judged as an arc discharge pulse for i consecutive times, the conduction time of the current pulse is immediately ended and the timing cycle of the next pulse is started. At the same time, AN2 is reset to 1 and j moving equivalents are retreated;

[0165] A4, A5, A6 and A7 are all non-negative finite decimals or integers.

[0166] The steps for controlling after judging a normal pulse are relatively simple and will not be described in detail here.

[0167] After it is judged as a short-circuit arc pulse, the pulse interval time needs to be adjusted to avoid frequent triggering of short-circuit arc pulses. Here is a specific adjustment method for the pulse interval time, as follows: set the interval time of the next pulse equal to the interval time of the previous pulse multiplied by AN1, and AN1 is initially set to 1; when it is judged as a short-circuit arc pulse, AN1 increases by 0.1; when it is judged as a normal pulse for 5 consecutive times, AN1 subtracts 0.1; when AN1=1.7 and it is judged as a short-circuit arc pulse for 5 consecutive times, the conduction time of the current pulse is immediately ended and the timing cycle of the next pulse is started. At the same time, AN1 is reset to 1, and the system alarm prompts short-circuit discharge, and external processing conditions need to be changed before discharge.

[0168] After it is judged as an arc discharge pulse, it is necessary to adjust the pulse interval time and selectively adjust the moving equivalent according to the actual situation to avoid frequent triggering of arc discharge pulses and ensure control accuracy. Here is a specific adjustment method for the pulse interval time and the moving equivalent, as follows: set the interval time of the next pulse equal to the interval time of the previous pulse multiplied by AN2, and AN2 is initially set to 1; when it is judged as an arc discharge pulse, AN2 increases by 0.1; when it is judged as a normal pulse for 5 consecutive times, AN2 subtracts 0.1; when AN2=1.7 and it is judged as an arc discharge pulse for 3 consecutive times, the conduction time of the current pulse is immediately ended and the timing cycle of the next pulse is started. At the same time, AN2 is reset to 1, and the servo feed system is controlled to retreat 1 moving equivalent.

[0169] After it is judged as an arc discharge pulse, the control steps are the most complicated. It is taken as an example to illustrate as follows: First, within a certain range, after it is judged as an arc discharge pulse, the interval time of the next pulse (hereinafter referred to as the interval time) is extended. The more times it is judged as an arc discharge pulse, the longer the interval time; secondly, here g is set to 1 for illustration. When it is judged as a normal pulse, the interval time is shortened to speed up the response speed of the system; after exceeding the above certain range, that is, when it is judged as an arc discharge pulse more times, the conduction time of the current pulse is immediately ended and the timing cycle of the next pulse is started, and the mobile equivalent is backed off. This setting provides an emergency processing mechanism for protecting the system or equipment.

[0170] There are several points that need to be emphasized and supplemented for the control steps of the above-mentioned arc discharge pulses, as follows: First, the interval time of the next pulse is continuously increasing within a certain range, rather than remaining unchanged, so that it can be continuously adjusted according to the number of recognition times of the arc discharge pulse to continuously reduce the frequency of occurrence of the arc discharge pulse; second, g is set to be greater than or equal to 2, at this time, the probability of an increase in the frequency of occurrence of the arc discharge pulse due to misjudgment can be reduced; third, i is set to be greater than or equal to 3 to improve the accuracy of the judgment result.

[0171] Here, the above-set g and i are further explained using the EDM process. If both g and i are greater than 1, the accuracy of judgment can be improved, the equipment and workpiece can be protected, the machining efficiency can be optimized, and the machining accuracy can be improved. This helps to achieve the stability and controllability of the machining process, and is suitable for machining areas that require high precision and stability. Specifically, to explain the protection of equipment and workpieces, if the interval time is immediately shortened after a single judgment, heat accumulation may occur due to excessive discharge, thereby damaging the electrode and workpiece. If the conduction time of the current pulse is terminated after a single judgment, excessive arc discharge may occur, causing damage to the equipment and workpiece.

[0172] Optionally, e is equal to h, and f is greater than i. At this time, the specific control mechanisms of the short-circuit arc pulse and the arc discharge pulse are relatively similar, and the difference mainly lies in f and i. f is greater than i, which conforms to the actual situation that the short-circuit arc pulse usually causes greater damage to equipment and workpieces, and requires more stringent judgment conditions to ensure that the pulse conduction time is terminated in time to avoid damage.

[0173] In this embodiment, the preset threshold voltage further includes a third preset threshold voltage corresponding to a good discharge pulse threshold;

[0174] The judgment result also includes judging as a good discharge pulse;

[0175] When the gap voltage count reaches the third preset threshold voltage, the delay time is recorded as Δ3.

[0176] The present application focuses on identifying short-circuit arc pulses and arc discharge pulses, but is also used to identify good discharge pulses.

[0177] The above gives the general and specific methods for determining Δ1 and Δ2. The general method for determining Δ3 is the same as the general method for Δ1 and Δ2. Here, the specific method for determining Δ3 is also given as a reference, as follows: the third preset threshold voltage is set to 60V. When the gap voltage rises to 60V, the trigger state identifier (set to CNTFLAG3) is set to 1, and the internal register (set to CNT3) starts rising edge counting (initial zero). When the gap voltage drops to 60V or when CNT3 counts to (In the formula, multiply by One half of the counting time is taken as the trigger signal for resetting CNTFLAG3; ON-1 is the discharge time set by the single pulse T inside the controller minus the margin time estimated by the line delay time (in µS); multiplying by 1000 means changing the original µS unit to nanosecond unit; because the crystal oscillator is 50MHZ, each count of CNT3 is 20 nanoseconds, so it needs to be divided by 20), CNT3 stops counting, CNTFLAG3 is reset to 0, and the delay time from the gap voltage rising from 60V to the CNT3 stopping counting is recorded as Δ3.

[0178] In this embodiment, the step of determining the delay time further includes the step of determining Δ3;

[0179] The step of judging Δ3 comprises:

[0180] Compare Δ3 with the preset value A8;

[0181] When Δ3<preset value A8, it is determined to be a good discharge pulse in the first state;

[0182] When the preset value A8<Δ3<preset value A9, it is determined to be a good discharge pulse in the second state;

[0183] Both A8 and A9 are non-negative finite decimals or integers.

[0184] When the gap voltage count reaches the third preset threshold voltage, the delay time is recorded as Δ3, and then the step of judging Δ3 is directly adopted, that is, different judgment steps are adopted corresponding to different preset threshold voltages, or in other words, the judgment steps are the same or similar as a whole, but there are some differences in the specific contents.

[0185] The preset value A8 and the preset value A9 are both determined based on experience in processing and testing, so as to ensure the accuracy of the measurement results.

[0186] Taking judging whether it is a good discharge pulse in the second state as an example, the key step is to determine the delay time Δ3, and then compare Δ3 with the preset value A8 and the preset value A9. Since fewer numerical values ​​or data are involved and fewer calculation steps are involved, the pulse state can be quickly identified, and then the pulse can be quickly processed. It is suitable for application scenarios with high requirements on the discharge quality of the power supply per unit time, and it is necessary to timely judge the good discharge pulses in different states and control the processing in time.

[0187] It should be emphasized that the good discharge pulse is divided into a good discharge pulse in a first state and a good discharge pulse in a second state according to the state. The present application can not only identify the good discharge pulse but also distinguish the good discharge pulse and then perform targeted control processing.

[0188] In this embodiment, when it is determined to be a good discharge pulse in the first state, the pulse interval time and the movement equivalent are maintained;

[0189] When it is determined to be a good discharge pulse in the second state, k movement equivalents are fed.

[0190] Although the good discharge pulse in the second state is a good discharge pulse, the active discharge time is short, and the servo system automatically feeds k movement equivalents.

[0191] Optionally, k is set to 1.

[0192] In this embodiment, the preset threshold voltage further includes a fourth preset threshold voltage corresponding to a no-load pulse threshold;

[0193] When the gap voltage count reaches the fourth preset threshold voltage, it is determined to be a no-load pulse, and the pulse interval time and the movement equivalent are maintained.

[0194] The setting of the fourth preset threshold voltage is also based on factors such as experience and practice.

[0195] When the gap voltage count reaches the fourth preset threshold voltage, the pulse is directly judged as a no-load pulse. The no-load pulse is an invalid discharge pulse caused by an excessively large gap or unsatisfied discharge conditions. Therefore, there is no need to adjust the pulse interval time and the moving equivalent.

[0196] Compared with judging short-circuit arc pulses and arc discharge pulses, judging no-load pulses is simpler and takes less time, with the following effects: on the one hand, since the judgment of no-load pulses is relatively simple and fast, the no-load state can be quickly identified, thereby speeding up the overall progress of pulse state identification; on the other hand, the rapid judgment of no-load pulses can reduce the processing and calculation times of invalid pulses, thereby reducing the computing load and energy consumption of the system; on the other hand, by quickly judging no-load pulses, the reliance on complex signal processing algorithms can be reduced, thereby reducing the complexity and cost of the pulse state identification process.

[0197] Also provided herein is an electric spark discharge pulse state identification and control system, which is used for the electric spark discharge pulse state identification and control method in any of the above embodiments, wherein the electric spark discharge pulse state identification and control system comprises a system microcontroller, a power amplifier, an electric discharge machining circuit, a gap detection circuit, a sampling voltage conditioning circuit, and a servo feed control circuit;

[0198] The first output terminal of the system microcontroller is connected to the input terminal of the servo feed control loop; the output terminal of the servo feed control loop is connected to the first input terminal of the gap detection loop;

[0199] The second output terminal of the system microcontroller is connected to the input terminal of the power amplifier; the output terminal of the power amplifier is connected to the input terminal of the electrical discharge machining circuit; the output terminal of the electrical discharge machining circuit is connected to the second input terminal of the gap detection circuit;

[0200] The output end of the gap detection loop is connected to the input end of the sampling voltage conditioning circuit; the output end of the sampling voltage conditioning circuit is connected to the input end of the system microcontroller;

[0201] The system microcontroller is used to generate a predetermined pulse and input the predetermined pulse into the power amplifier; the power amplifier is used to amplify the predetermined pulse to form an amplified pulse, and input the amplified pulse into the discharge machining circuit; the discharge machining circuit is driven by the amplified pulse to perform pulse-type discharge; the gap detection circuit is used to detect the gap voltage between the workpiece and the electrode in the discharge machining circuit and input the gap voltage into the sampling voltage conditioning circuit; the sampling voltage conditioning circuit is used to condition the gap voltage into a low-voltage signal allowed to be input by the external IO input port of the system microcontroller; the system microcontroller makes a judgment based on the low-voltage signal, and can adjust the pulse interval time and the movement equivalent through the power amplifier and the servo feed control circuit according to the judgment result.

[0202] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for identifying and controlling the state of an electric spark discharge pulse, characterized in that: The following steps are involved: Obtain the gap voltage and determine whether it is a rising edge voltage; Comparing the gap voltage determined to be a rising edge voltage with a preset threshold voltage; The preset threshold voltage at least includes a first preset threshold voltage corresponding to a short-circuit arc pulse threshold and a second preset threshold voltage corresponding to an arc discharge pulse threshold; When the gap voltage determined to be a rising edge voltage is the same as any one of the preset threshold voltages, the trigger state identifier is set to 1, and counting starts from the preset value A1; When any one of the counting stop conditions is met, counting is stopped, the state identifier is cleared and the count value is returned to the preset value A1; the counting stop condition includes the gap voltage dropping to the preset threshold voltage reached during counting or the preset counting value; the preset value includes at least a first counting value B1 corresponding to the first preset threshold voltage and a second counting value B2 corresponding to the second preset threshold voltage; Calculate the delay time between the start and stop time points of counting; The delay time is judged and a judgment result is output; the judgment result includes a judgment as a short-circuit arc pulse, a judgment as an arc discharge pulse and a judgment as a normal pulse; Control is performed according to the judgment result; the control content includes at least one of maintaining the pulse interval time and the movement equivalent, adjusting the pulse interval time, and adjusting the movement equivalent; A1, B1 and B2 are all non-negative finite decimals or integers.

2. The method for identifying and controlling the spark discharge pulse state according to claim 1, characterized in that: When the gap voltage is identical to at least two of the preset threshold voltages at different time points during the rising edge process, only the judgment result corresponding to the maximum preset threshold voltage is output, and the maximum preset threshold voltage is the preset threshold voltage with the largest value among the preset threshold voltages that are identical to the gap voltage at different time points.

3. The method for identifying and controlling the spark discharge pulse state according to claim 2, characterized in that: When the gap voltage count reaches the first preset threshold voltage, the delay time is recorded as Δ1; When the gap voltage count reaches the second preset threshold voltage, the delay time is recorded as Δ2; The step of judging the delay time includes a step of judging Δ1 and a step of judging Δ2; The step of judging Δ1 comprises: Compare Δ1 with a preset value A2; When Δ1<preset value A2, it is judged as a short-circuit arc pulse; When Δ1>preset value A2, it is judged as a normal pulse; The step of judging Δ2 comprises: Compare Δ2 with a preset value A3; When Δ2<preset value A3, it is judged as an arc discharge pulse; When Δ2>preset value A3, it is judged as a normal pulse; A2 and A3 are both non-negative finite decimals or integers.

4. The method for identifying and controlling the spark discharge pulse state according to claim 3, characterized in that: The first count value The preset value The second count value The preset value Both n1 and n2 are positive integers; The ON is the discharge time set by the single pulse T; The z is the time required for one count.

5. The method for identifying and controlling the spark discharge pulse state according to any one of claims 1 to 4, characterized in that: When it is judged as a normal pulse, the pulse interval time and movement equivalent are maintained; When it is judged as a short-circuit arc pulse, adjust the pulse interval time; When it is determined to be an arc discharge pulse, the pulse interval time and movement equivalent are adjusted.

6. The method for identifying and controlling the spark discharge pulse state according to any one of claims 1 to 4, characterized in that: The step of controlling according to the judgment result includes the step of controlling when judging as a normal pulse, the step of controlling when judging as a short-circuit arc pulse, and the step of controlling when judging as an arc discharge pulse; The step of determining a normal pulse and performing control comprises: Maintain pulse interval time and movement equivalent; The step of determining that the short-circuit arc pulse is controlled comprises: Set the next pulse interval to be equal to the previous pulse interval multiplied by AN1; The AN1 is initially set to 1; When it is determined to be a short-circuit arc pulse, the AN1 increases by a preset value A4; When the pulse is judged as normal for d consecutive times, the preset value A5 is subtracted from AN1; When AN1=e and it is judged as a short-circuit arc pulse for f consecutive times, the conduction time of the current pulse is immediately ended and the timing cycle of the next pulse is started, and AN1 is reset to 1 at the same time; The step of determining that an arc discharge pulse is to be controlled comprises: Set the next pulse interval to be equal to the previous pulse interval multiplied by AN2; The AN2 is initially set to 1; When it is judged to be an arc discharge pulse, the AN2 increases by a preset value A6; When the pulse is judged as normal for g times in a row, the preset value A7 is subtracted from AN2; When AN2 = h and it is judged as an arc discharge pulse for i consecutive times, the conduction time of the current pulse is immediately ended and the timing cycle of the next pulse is started. At the same time, AN2 is reset to 1 and j moving equivalents are retreated; A4, A5, A6, A7, e and h are all non-negative finite decimals or integers; The d, f, g, i and j are all non-negative integers; Both AN1 and AN2 are non-negative finite decimals or integers.

7. The method for identifying and controlling the spark discharge pulse state according to claim 4, characterized in that: The preset threshold voltage also includes a third preset threshold voltage corresponding to a good discharge pulse threshold; The judgment result also includes judging as a good discharge pulse; When the gap voltage count reaches the third preset threshold voltage, the delay time is recorded as Δ3.

8. The method for identifying and controlling the spark discharge pulse state according to claim 7, characterized in that: The step of determining the delay time further includes the step of determining Δ3; The step of judging Δ3 comprises: Compare Δ3 with the preset value A8; When Δ3<preset value A8, it is determined to be a good discharge pulse in the first state; When the preset value A8<Δ3<preset value A9, it is determined to be a good discharge pulse in the second state; Both A8 and A9 are non-negative finite decimals or integers.

9. The method for identifying and controlling the spark discharge pulse state according to claim 8, characterized in that: When it is determined to be a good discharge pulse in the first state, the pulse interval time and the movement equivalent are maintained; When it is judged to be a good discharge pulse in the second state, k movement equivalents are fed; The k is a non-negative integer.

10. The method for identifying and controlling the spark discharge pulse state according to claim 4, characterized in that: The preset threshold voltage also includes a fourth preset threshold voltage corresponding to a no-load pulse threshold; When the gap voltage count reaches the fourth preset threshold voltage, it is determined to be a no-load pulse, and the pulse interval time and the movement equivalent are maintained.

11. An electric spark discharge pulse state identification and control system, used in the electric spark discharge pulse state identification and control method according to any one of claims 1 to 10, characterized in that: The electric spark discharge pulse state identification and control system includes a system microcontroller, a power amplifier, an electric discharge machining circuit, a gap detection circuit, a sampling voltage conditioning circuit, and a servo feed control circuit; The first output terminal of the system microcontroller is connected to the input terminal of the servo feed control loop; the output terminal of the servo feed control loop is connected to the first input terminal of the gap detection loop; The second output terminal of the system microcontroller is connected to the input terminal of the power amplifier; the output terminal of the power amplifier is connected to the input terminal of the electrical discharge machining circuit; the output terminal of the electrical discharge machining circuit is connected to the second input terminal of the gap detection circuit; The output end of the gap detection loop is connected to the input end of the sampling voltage conditioning circuit; the output end of the sampling voltage conditioning circuit is connected to the input end of the system microcontroller; The system microcontroller is used to generate a predetermined pulse and input the predetermined pulse into the power amplifier; the power amplifier is used to amplify the predetermined pulse to form an amplified pulse, and input the amplified pulse into the discharge machining circuit; the discharge machining circuit is driven by the amplified pulse to perform pulse-type discharge; the gap detection circuit is used to detect the gap voltage between the workpiece and the electrode in the discharge machining circuit and input the gap voltage into the sampling voltage conditioning circuit; the sampling voltage conditioning circuit is used to condition the gap voltage into a low-voltage signal allowed to be input by the external IO input port of the system microcontroller; the system microcontroller makes a judgment based on the low-voltage signal, and can adjust the pulse interval time and the movement equivalent through the power amplifier and the servo feed control circuit according to the judgment result.

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