Control method and system for a pulsed power supply

Abstract

This invention discloses a pulse power supply control method applied to electrical discharge machining (EDM), which includes multiple machining parameters. The pulse power supply control method includes the following steps: classifying the multiple machining parameters into a first category of parameters and a second category of parameters, wherein the first category of parameters includes at least one of discharge polarity selection, absorption circuit selection, inductor circuit selection, and voltage level; and the second category of parameters includes at least one of pulse duration, pulse interval duration, and discharge current value; restricting the first category of parameters to be updated only before the start of EDM; and detecting whether the discharge current value and / or discharge voltage value are within a preset range; if the discharge current value and / or discharge voltage value are within the preset range, then the second category of parameters to be updated is cached, and the second category of parameters is updated only during the pulse interval; if the discharge current value and / or discharge voltage value exceed the preset range, then the second category of parameters is updated during the pulse duration.

Description

Technical Field

[0001] This invention relates to the field of electrical discharge machining technology, and in particular to a control method and system for a pulse power supply. Background Technology

[0002] Electrical Discharge Machining (EDM) technology utilizes the instantaneous high temperature generated during pulsed discharge to erode materials. The control of the pulse power supply directly affects the efficiency, accuracy, and stability of the machining process. Current technologies control the pulses via software, for example, by generating pulses through timers, then processing the detection signals and adjusting parameters using software. This results in large pulse width jitter (typically on the microsecond level), leading to unstable machining quality. Parameter updates may occur during the duration of the discharge pulse, causing pulse distortion or even power transistor shoot-through. Emergency events such as arc detection require waiting for software interruption, resulting in long response times and ineffective arc suppression. Furthermore, critical settings such as polarity and absorption circuits may be mistakenly altered during machining, posing safety hazards. Alternatively, pulse control can be achieved through a Digital Signal Processor (DSP) and a Field Programmable Gate Array (FPGA). The FPGA is used only for pulse generation, while the DSP is responsible for processing the software algorithms and communication. This approach is costly and complex to develop, and parameter updates and emergency responses still need to be handled by the software, with the response rate limited by the software's operating cycle.

[0003] Therefore, to address the aforementioned technical problems, it is necessary to provide a control method and system for pulse power supplies that can respond promptly to emergencies, ensure the safety of parameter updates, and balance processing efficiency, quality, and equipment safety. Summary of the Invention

[0004] The purpose of this invention is to provide a control method and system for pulse power supplies that can respond promptly to emergencies, ensure the safety of parameter updates, and achieve a balance between processing efficiency, quality, and equipment safety.

[0005] To achieve the above objectives, a specific embodiment of the present invention provides the following technical solution:

[0006] An embodiment of the present invention provides a pulse power supply control method applied to electrical discharge machining (EDM). The EDM includes multiple machining parameters. The control system of the pulse power supply generates discharge pulse signals according to the multiple machining parameters and drives the power device to output current control signals.

[0007] The control method for the pulse power supply includes the following steps:

[0008] Multiple processing parameters are classified into a first category of parameters and a second category of parameters. The first category of parameters includes at least one of discharge polarity selection, absorption circuit selection, inductor circuit selection, and voltage level. The second category of parameters includes at least one of pulse duration, pulse interval duration, and discharge current value.

[0009] The first type of parameters are restricted to being updated only before the electrical discharge machining begins; and,

[0010] The system detects whether the discharge current value and / or discharge voltage value are within a preset range. If the discharge current value and / or discharge voltage value are within the preset range, the second type of parameter to be updated is cached, and the second type of parameter is updated only during the pulse interval. If the discharge current value and / or discharge voltage value exceed the preset range, the second type of parameter is updated during the pulse duration.

[0011] Preferably, the step of detecting whether the discharge current value and / or discharge voltage value are within a preset range further includes:

[0012] When the discharge current value and / or discharge voltage value are detected to exceed the preset range, the severity of the discharge current value and / or discharge voltage value exceeding the preset range is detected, and the updated target value of the second type of parameter is determined according to the severity of the exceeding the preset range.

[0013] The severity of exceeding the preset range includes at least one of the following: duration of exceeding the preset range, magnitude of exceeding the preset range, and frequency of exceeding the preset range.

[0014] More preferably, the step of determining the update target value of the second type of parameter based on the severity of exceeding the preset range further includes:

[0015] The severity of cases exceeding the preset range is classified into three levels: Level 1, Level 2, and Level 3.

[0016] The first level includes at least one of the following conditions: the duration of the discharge exceeding the preset range is greater than the first duration, the discharge current value exceeds the preset range and is greater than the first current value, the discharge voltage value exceeds the preset range and is greater than the first voltage value, and the frequency of occurrence of the preset range is greater than the first number.

[0017] The second level includes at least one of the following conditions: the duration of the discharge exceeding the preset range is greater than the second duration, the discharge current value exceeds the preset range and is greater than the second current value, the discharge voltage value exceeds the preset range and is greater than the second voltage value, and the occurrence frequency of the preset range is greater than the second number.

[0018] The third level includes at least one of the following conditions: the duration of the discharge exceeding the preset range is greater than the third duration, the discharge current value exceeds the preset range and is greater than the third current value, the discharge voltage value exceeds the preset range and is greater than the third voltage value, and the frequency of occurrence within the preset range is greater than the third number.

[0019] The first duration, the second duration, and the third duration increase sequentially; the first current value, the second current value, and the third current value increase sequentially; the first voltage value, the second voltage value, and the third voltage value increase sequentially; and the first number of times, the second number of times, and the third number of times increase sequentially.

[0020] More preferably, the step of determining the update target value of the second type of parameter based on the severity of exceeding the preset range includes:

[0021] When the severity exceeds the preset range and is at level one, adjust the pulse duration and / or pulse interval duration;

[0022] When the severity exceeds the preset range and reaches level two, the discharge current value is adjusted to an abnormal adjustment current value, wherein the abnormal adjustment current value is less than or equal to 50% of the current discharge current value.

[0023] When the severity level exceeds the preset range and reaches Level 3, adjust the discharge current value to the preset safe current value.

[0024] More preferably, the preset safe current value is 0A.

[0025] More preferably, the step of detecting whether the discharge current value and / or discharge voltage value are within a preset range further includes:

[0026] Multiple discharge current values ​​are generated based on multiple data sources, including user-set base current values, dynamic current curves, abnormal adjustment current values, and preset safe current values. The discharge current value is then selected based on the following priority rules from highest to lowest:

[0027] When the severity level exceeds the preset range to level three, the preset safe current value is output.

[0028] When the severity of the abnormality exceeds the preset range and is at level two, the abnormal adjustment current value is output.

[0029] When a dynamic current curve exists, output the dynamic current curve value;

[0030] Output the base current value.

[0031] Preferably, in the step of detecting whether the discharge current value and / or discharge voltage value are within a preset range, when updating the second type of parameter during the pulse interval, the start of the time period for updating the second type of parameter is closer to the end of the previous pulse duration period than the start of the next pulse duration period.

[0032] Preferably, in the step of detecting whether the discharge current value and / or discharge voltage value are within a preset range, the discharge current value and the discharge voltage value are detected multiple times within a pulse duration.

[0033] More preferably, the step of detecting whether the discharge current value and / or discharge voltage value are within a preset range includes:

[0034] The discharge current value and / or discharge voltage value are detected to exceed the preset range by a certain amount. The discharge current value exceeds the preset range by a comparison between the average of multiple detected discharge current values ​​and the preset range of discharge current. The discharge voltage value exceeds the preset range by a comparison between the average of multiple detected discharge voltage values ​​and the preset range of discharge voltage.

[0035] An embodiment of the present invention further provides a pulse power supply control system applied to electrical discharge machining (EDM), wherein the EDM includes multiple machining parameters, and the pulse power supply control system drives power devices according to the pulse power supply control method described above.

[0036] The control system of the pulse power supply includes:

[0037] A pulse generation module is connected to the power device. The pulse generation module is used to generate a discharge pulse signal according to multiple processing parameters and drive the power device to output a current control signal.

[0038] A status detection module is used to detect the discharge current value and / or discharge voltage value of the discharge gap of the power device;

[0039] The signal path is adjusted and connected between the state detection module and the pulse generation module to receive a second type of parameter from multiple processing parameters and control the updating of the second type of parameter; and,

[0040] The parameter management module has a cache unit, which is used to cache the second type of parameters among multiple processing parameters. The parameter management module is connected to the status detection module and the pulse generation module respectively, and controls the timing of loading or updating the processing parameters in the cache unit according to the type of processing parameters and the current processing stage.

[0041] The pulse generation module includes an arbitration unit. If the discharge current value and / or discharge voltage value are within a preset range, the arbitration unit switches to connect with the parameter management module so that the second type of parameter to be updated is stored in the cache unit and updated only during the pulse interval. If the discharge current value and / or discharge voltage value exceed the preset range, the arbitration unit switches to connect with the adjustment signal path and updates the second type of parameter during the pulse duration.

[0042] Preferably, the pulse generation module, the status detection module, the adjustment signal path, and the parameter management module are integrated on the same substrate.

[0043] Compared with the prior art, the pulse power supply control method provided by the embodiments of the present invention is applied to electrical discharge machining (EDM). The EDM includes multiple processing parameters. The pulse power supply control system generates discharge pulse signals corresponding to these multiple processing parameters and drives power devices to output current control signals. The pulse power supply control method includes the following steps: classifying the multiple processing parameters into a first category of parameters and a second category of parameters, wherein the first category of parameters includes at least one of discharge polarity selection, absorption circuit selection, inductor circuit selection, and voltage level; and the second category of parameters includes at least one of pulse duration, pulse interval duration, and discharge current value; restricting the first category of parameters to be updated only before the start of EDM; and detecting whether the discharge current value and / or discharge voltage value are within a preset range; if the discharge current value and / or discharge voltage value are within the preset range, then the second category of parameters to be updated is cached, and the second category of parameters is updated only during the pulse interval; if the discharge current value and / or discharge voltage value exceed the preset range, then the second category of parameters is updated during the pulse duration. Thus, the pulse power supply control system can respond promptly to emergencies and ensure the safety of parameter updates, achieving a balance between processing efficiency, quality, and equipment safety. Attached Figure Description

[0044] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0045] Figure 1 This is a schematic block diagram of the module structure of the control system of the pulse power supply in one embodiment of the present invention;

[0046] Figure 2 This is a schematic flowchart of a pulse power supply control method according to an embodiment of the present invention. Detailed Implementation

[0047] To enable those skilled in the art to better understand the technical solutions in this disclosure, the technical solutions in the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments in this disclosure, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this disclosure.

[0048] Please see Figure 1 , Figure 1 This is a schematic block diagram of the module structure of the pulse power supply control system according to an embodiment of the present invention. The pulse power supply control system provided in this embodiment is applied to electrical discharge machining (EDM) of a workpiece. The EDM includes multiple machining parameters. The pulse power supply control system is connected to a power device. The pulse power supply control system generates discharge pulse signals according to the multiple machining parameters and drives the power device to output current control signals. In other words, the pulse power supply control system is the decision-making end of the EDM, and the power device is the execution end of the EDM. In this embodiment, the power device includes a discharge power board 10 and a tool electrode (not shown in the figure). The discharge power board 10 includes a power switch (e.g., IGBT, MOSFET, etc.) to output a current control signal according to the discharge pulse signal. The tool electrode then discharges current according to the current control signal to machine the workpiece. Furthermore, the power switch of the discharge power board 10 is also used to perform circuit cutoff operations, etc. However, practical applications are not limited to this.

[0049] like Figure 1As shown, the control system of the pulse power supply includes a parameter management module 21, a pulse generation module 22, a status detection module 23, and an adjustment signal path 24. In a preferred embodiment, the parameter management module 21, the pulse generation module 22, the status detection module 23, and the adjustment signal path 24 are integrated on the same substrate, enabling a single chip to integrate core functions such as parameter management, pulse generation, status detection, and adjustment signal path. Each module is independent and has standardized interfaces, facilitating system expansion, maintenance, and upgrades. The pulse generation module 22 is connected to the discharge power board 10 of the power device. The pulse generation module 22 is used to generate discharge pulse signals according to multiple processing parameters and drive the discharge power board 10 to output current control signals. The status detection module 23 detects the discharge current value and / or discharge voltage value of the discharge gap between the tool electrode and the workpiece (real-time detection in this embodiment, but not limited to this), and outputs a detection signal reflecting the discharge status (i.e., the discharge current value and / or discharge voltage value). In some embodiments, the control system of the pulse power supply also includes an alarm module (not shown in the figure), used to receive abnormal signals from the discharge power board 10 and provide an alarm. The adjustment signal path 24 is connected between the status detection module 23 and the pulse generation module 22. It receives processing parameters and directly transmits them to the pulse generation module 22 for updating, thereby generating a discharge pulse signal with updated processing parameters. The parameter management module 21 is connected between the pulse generation module 22 and the status detection module 23. The parameter management module 21 has a buffer unit (not shown in the figure). The parameter management module 21 receives processing parameters and stores them in the buffer unit. Based on the type of processing parameters and the current processing stage (e.g., before processing begins, during pulse duration, or during pulse interval), it controls the timing of loading or updating each processing parameter. In other words, the adjustment signal path 24 can update the processing parameters immediately after receiving them, while the parameter management module 21 buffers the processing parameters and updates them at an appropriate time.

[0050] In this embodiment, the parameter management module 21 is connected to the host computer 30 via the communication interface module 25 (e.g., EtherCAT or other similar bus). In other embodiments, the host computer 30 can be replaced by a microcontroller, and is not limited thereto. The host computer 30 is equipped with a software system to realize processing path planning, motion control, and provide a human-machine interface. Some of the processing parameters mentioned above (e.g., the user-set basic current value) can be input by the operator through the human-machine interface; other processing parameters (processing parameters related to equipment safety configuration, such as discharge polarity selection, absorption circuit selection, inductor circuit selection, voltage level, etc.) are stored in a storage module (not shown in the figure) included in the pulse power supply control system. These other processing parameters can also be adaptively adjusted through the human-machine interface or other interaction methods according to different processing requirements and changes in the processing environment; still other processing parameters (e.g., dynamic current curve, pulse interval duration) are calculated and obtained by the processing unit (not shown in the figure) of the parameter management module 21. These other processing parameters will change accordingly based on the actual situation during the processing without manual intervention; however, the actual application is not limited to this.

[0051] In some embodiments, the parameter management module 21 can also be connected to an external device control module (not shown in the figure) via the communication interface module 25 to manage auxiliary equipment such as discharge polarity switching, cooling fan, and absorption circuit.

[0052] Based on the above, please participate again. Figure 2 , Figure 2 This is a schematic flowchart of a pulse power supply control method according to an embodiment of the present invention. The pulse power supply control system provided by the embodiment of the present invention includes the following steps:

[0053] Multiple processing parameters are categorized into a first category and a second category. The first category of parameters is restricted to being updated only before the start of the electrical discharge machining (EDM). The discharge current and / or discharge voltage values ​​are detected to ensure they are within a preset range. If the discharge current and / or discharge voltage values ​​are within the preset range, the second category of parameters to be updated is cached and updated only during pulse intervals. If the discharge current and / or discharge voltage values ​​exceed the preset range (i.e., the discharge current (discharge voltage) is greater than the maximum value of the preset range or less than the minimum value), the second category of parameters is updated during the pulse duration. The first category of parameters is related to equipment safety configuration and includes at least one of discharge polarity selection, absorption circuit selection, inductor circuit selection, and voltage level. The second category of parameters is related to discharge energy and pulse timing and includes at least one of pulse duration, pulse interval duration, and discharge current value.

[0054] It should be noted that situations where the discharge current and / or discharge voltage values ​​exceed the preset range include: open circuit (abnormally high discharge voltage, no discharge current), short circuit (abnormally low discharge voltage, excessively high discharge current), and arcing (abnormally low discharge voltage, excessively high discharge current). These situations all constitute abnormal discharges in electrical discharge machining, which typically occur within the pulse duration. During an abnormal discharge, the second type of parameters needs to be updated immediately to ensure equipment safety. This can be done immediately during the current pulse duration upon detecting an abnormal discharge, and the adjustment signal path 24 can receive the second type of parameters to be updated. During normal discharge, the update of the second type of parameters can occur during the pulse interval immediately following the end of the current pulse duration, and the parameter management module 21 can receive the second type of parameters to be updated.

[0055] Thus, update commands for processing parameters requiring urgent updates are directly applied to the pulse generation module 22 via an independent adjustment signal path 24. This achieves a response efficiency far exceeding that of software processing for abnormal discharges, with a response time reaching the nanosecond level. Processing parameters related to equipment safety configuration are locked during processing to prevent equipment damage or safety accidents caused by misoperation. Processing parameters not requiring urgent updates can be updated during pulse intervals to avoid interfering with ongoing discharges, thus ensuring equipment safety. Furthermore, pulse timing is implemented through logic circuits in the pulse generation module 22 (e.g., pulse timing control unit, gate drive unit, etc.) and the discharge power board 10 (e.g., IGBT, MOSFET, etc.), resulting in minimal pulse width jitter and improved workpiece surface processing quality.

[0056] In this embodiment, the pulse generation module 22 has an arbitration unit 221. When the discharge current value and / or discharge voltage value are within a preset range, the arbitration unit 221 switches to connect with the parameter management module 21, so that the second type of parameter to be updated is stored in the cache unit, and the second type of parameter is updated only during the pulse interval. When the discharge current value and / or discharge voltage value exceed the preset range, the arbitration unit 221 switches to connect with the adjustment signal path 24, and updates the second type of parameter during the pulse duration. The working principle of the arbitration unit 221 and its specific connection method with the parameter management module 21 and the adjustment signal path 24 are well known to those skilled in the art and will not be described in detail here.

[0057] In a preferred embodiment, in the step of detecting whether the discharge current value and / or discharge voltage value are within a preset range, when updating the second type of parameters during the pulse interval, the start of the time period for updating the second type of parameters is closer to the end of the previous pulse duration period than the start of the next pulse duration period, so as to avoid affecting the preparation work for the discharge of the next pulse duration period.

[0058] In a preferred embodiment, in the step of detecting whether the discharge current value and / or discharge voltage value are within a preset range, the discharge current value and the discharge voltage value are detected multiple times within a pulse duration. In other words, the sampling frequency of the discharge current value and discharge voltage value is higher than the frequency of the discharge pulse, so that the discharge current value and discharge voltage value are sampled more accurately. In this embodiment, the sampling results of the discharge current value and discharge voltage value can also be reported to the host computer 30 through the communication interface module 25 to realize servo control and monitoring of the processing status.

[0059] In a preferred embodiment, the step of detecting whether the discharge current value and / or discharge voltage value are within a preset range further includes: when the discharge current value and / or discharge voltage value are detected to exceed the preset range, detecting the severity of the discharge current value and / or discharge voltage value exceeding the preset range, and determining the updated target value of the second type of parameter based on the severity of exceeding the preset range.

[0060] The severity of exceeding the preset range includes at least one of the following: duration of exceeding the preset range, magnitude of exceeding the preset range, and frequency of exceeding the preset range.

[0061] Taking the detection of discharge current and / or discharge voltage values ​​exceeding preset ranges as an example, the extent to which the discharge current exceeds the preset range is obtained by comparing the average of multiple detected discharge current values ​​with the preset range of discharge current. Similarly, the extent to which the discharge voltage exceeds the preset range is obtained by comparing the average of multiple detected discharge voltage values ​​with the preset range of discharge voltage. It should be noted that, within the duration of a discharge pulse, before the discharge pulse ends, the average of multiple detected discharge current values ​​specifically refers to the average of the currently detected discharge current values, and its calculation result is updated in real time as the duration of the discharge pulse progresses. The average of multiple detected discharge voltage values ​​specifically refers to the average of the currently detected discharge voltage values, and its calculation result is updated in real time as the duration of the discharge pulse progresses. The criteria and methods for judging the severity of other exceedances (duration of exceedance, frequency of exceedance, etc.) are similar and will not be elaborated further.

[0062] Preferably, the step of determining the update target value of the second type of parameter based on the severity of exceeding the preset range further includes: classifying the severity of exceeding the preset range into a first level, a second level, and a third level.

[0063] The first level includes at least one of the following conditions: the duration of the discharge exceeding the preset range is greater than the first duration, the discharge current value exceeds the preset range and is greater than the first current value, the discharge voltage value exceeds the preset range and is greater than the first voltage value, and the frequency of occurrence of the preset range is greater than the first number.

[0064] The second level includes at least one of the following conditions: the duration of the discharge exceeding the preset range is greater than the second duration, the discharge current value exceeds the preset range and is greater than the second current value, the discharge voltage value exceeds the preset range and is greater than the second voltage value, and the occurrence frequency of the preset range is greater than the second number.

[0065] The third level includes at least one of the following conditions: the duration of the discharge exceeding the preset range is greater than the third duration; the discharge current value exceeds the preset range and is greater than the third current value; the discharge voltage value exceeds the preset range and is greater than the third voltage value; and the frequency of occurrence within the preset range is greater than the third number.

[0066] In this system, the first duration, the second duration, and the third duration increase sequentially; the first current value, the second current value, and the third current value increase sequentially; the first voltage value, the second voltage value, and the third voltage value increase sequentially; and the first number of times, the second number of times, and the third number of times increase sequentially. That is to say, the severity of the first level is relatively low, and the severity of the third level is relatively high. It should be noted that the grading standards for the first, second, and third levels can be specifically designed by those skilled in the art based on actual processing requirements, processing environment, and other requirements, and are not limited thereto.

[0067] Furthermore, the step of determining the update target value of the second type of parameter based on the severity of exceeding the preset range includes:

[0068] When the severity of the exceedance of the preset range is level one, adjust the pulse duration and / or pulse interval duration. For example, if the severity of the exceedance of the preset range is relatively small, the duration of the current pulse duration can be shortened, or the duration of the pulse interval immediately adjacent to the current pulse duration can be extended.

[0069] When the severity exceeds the preset range and reaches level two, the discharge current value is adjusted to an abnormal adjustment current value (output by the status detection module 23), wherein the abnormal adjustment current value is less than or equal to 50% of the current discharge current value.

[0070] When the severity level exceeds the preset range and reaches level three, the discharge current value is adjusted to the preset safe current value (output by the status detection module 23). In this embodiment, the preset safe current value is 0A, which means that the circuit is forcibly current limited or forcibly shut down to protect the circuit's safety.

[0071] In a preferred embodiment, the step of detecting whether the discharge current value and / or discharge voltage value are within a preset range further includes: generating multiple discharge current values ​​(belonging to the second type of parameters) according to multiple sources; the pulse generation module 22 analyzes the multiple discharge current values ​​according to a priority rule and generates a corresponding discharge pulse signal. The sources include a user-set base current value, a dynamic current curve, an abnormal adjustment current value, and a preset safe current value. Specifically, the discharge current value is determined according to the following priority rule from high to low:

[0072] When the highest priority and the severity exceeding the preset range is level three, the preset safe current value is output;

[0073] When the second highest priority and the severity of the abnormality exceeding the preset range is level two, the abnormal adjustment current value is output.

[0074] The third priority is to output the dynamic current curve value when a dynamic current curve exists (i.e., the slope of the rising or falling edge of the pulse signal is set).

[0075] Lowest priority, output the base current value.

[0076] In other words, the basis for the discharge current value controlled by the pulse generation module 22 can be the user-set basic current value, the dynamic current curve that changes over time (executed by the dynamic current curve generation module in this embodiment), the abnormal adjustment current value of the status detection unit, and the forced current limiting value of the safety protection circuit. At the same time point, the pulse generation module 22 selects one source to determine the discharge current value and generates a discharge pulse signal according to the above priority rules, so as to generate or update the next discharge current.

[0077] In this embodiment, the arbitration unit 221 is also connected to the dynamic current curve generation module, meaning that the aforementioned priority rules are specifically executed by the arbitration unit 221. During normal processing, without safety protection triggering or abnormal discharge detection, the dynamic current curve generation module is not activated, and the arbitration unit 221 selects the user-set base current value for output. After the dynamic current curve generation module is activated, the base current value remains valid during the rising edge period of the pulse signal, but the dynamic current curve generation module outputs the slope change value of the rising edge, and the arbitration unit 221 selects this dynamic current curve value for output to adjust the slope of the rising edge. If arcing is detected during processing, the status detection module 23 outputs an abnormal adjustment current value (e.g., 50% of the base current), and this request has a higher priority than the dynamic current curve value, so the arbitration unit 221 selects this abnormal adjustment current value for output. If a short circuit is detected during processing, the safety protection circuit (in the status detection module 23) outputs a forced current limit (e.g., 0A), and the forced current limit has the highest priority, so the arbitration unit 221 immediately selects the forced current limit value and stops all outputs.

[0078] In summary, the pulse power supply control method provided by the embodiments of the present invention is applied to electrical discharge machining (EDM). The EDM includes multiple processing parameters. The pulse power supply control system generates discharge pulse signals corresponding to these multiple processing parameters and drives power devices to output current control signals. The pulse power supply control method includes the following steps: classifying the multiple processing parameters into a first category of parameters and a second category of parameters, wherein the first category of parameters includes at least one of discharge polarity selection, absorption circuit selection, inductor circuit selection, and voltage level; and the second category of parameters includes at least one of pulse duration, pulse interval duration, and discharge current value; restricting the first category of parameters to be updated only before the start of EDM; and detecting whether the discharge current value and / or discharge voltage value are within a preset range; if the discharge current value and / or discharge voltage value are within the preset range, then the second category of parameters to be updated is cached, and the second category of parameters is updated only during the pulse interval; if the discharge current value and / or discharge voltage value exceed the preset range, then the second category of parameters is updated during the pulse duration. Thus, the pulse power supply control system can respond promptly to emergencies and ensure the safety of parameter updates, achieving a balance between processing efficiency, quality, and equipment safety.

[0079] It will be apparent to those skilled in the art that this disclosure is not limited to the details of the exemplary embodiments described above, and that this disclosure can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of this disclosure is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this disclosure. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0080] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A pulse power supply control method, applied to electrical discharge machining, characterized in that, The electrical discharge machining includes multiple machining parameters. The control system of the pulse power supply generates discharge pulse signals according to the multiple machining parameters and drives the power device to output current control signals. The control method for the pulse power supply includes the following steps: Multiple processing parameters are classified into a first category of parameters and a second category of parameters. The first category of parameters includes at least one of discharge polarity selection, absorption circuit selection, inductor circuit selection, and voltage level. The second category of parameters includes at least one of pulse duration, pulse interval duration, and discharge current value. The first type of parameters are restricted to being updated only before the electrical discharge machining begins; and, The system detects whether the discharge current value and / or discharge voltage value are within a preset range. If the discharge current value and / or discharge voltage value are within the preset range, the second type of parameter to be updated is cached, and the second type of parameter is updated only during the pulse interval. If the discharge current value and / or discharge voltage value exceed the preset range, the second type of parameter is updated during the pulse duration.

2. The pulse power supply control method as described in claim 1, characterized in that, The step of detecting whether the discharge current value and / or discharge voltage value are within a preset range also includes: When the discharge current value and / or discharge voltage value are detected to exceed the preset range, the severity of the discharge current value and / or discharge voltage value exceeding the preset range is detected, and the updated target value of the second type of parameter is determined according to the severity of the exceeding the preset range. The severity of exceeding the preset range includes at least one of the following: duration of exceeding the preset range, magnitude of exceeding the preset range, and frequency of exceeding the preset range.

3. The pulse power supply control method as described in claim 2, characterized in that, The step of determining the update target value of the second type of parameter based on the severity of exceeding the preset range also includes: The severity of cases exceeding the preset range is classified into three levels: Level 1, Level 2, and Level 3. The first level includes at least one of the following conditions: the duration of the discharge exceeding the preset range is greater than the first duration, the discharge current value exceeds the preset range and is greater than the first current value, the discharge voltage value exceeds the preset range and is greater than the first voltage value, and the frequency of occurrence of the preset range is greater than the first number. The second level includes at least one of the following conditions: the duration of the discharge exceeding the preset range is greater than the second duration, the discharge current value exceeds the preset range and is greater than the second current value, the discharge voltage value exceeds the preset range and is greater than the second voltage value, and the occurrence frequency of the preset range is greater than the second number. The third level includes at least one of the following conditions: the duration of the discharge exceeding the preset range is greater than the third duration, the discharge current value exceeds the preset range and is greater than the third current value, the discharge voltage value exceeds the preset range and is greater than the third voltage value, and the frequency of occurrence within the preset range is greater than the third number. The first duration, the second duration, and the third duration increase sequentially; the first current value, the second current value, and the third current value increase sequentially; the first voltage value, the second voltage value, and the third voltage value increase sequentially; and the first number of times, the second number of times, and the third number of times increase sequentially.

4. The pulse power supply control method as described in claim 3, characterized in that, The steps for determining the updated target value of the second type of parameter based on the severity of exceeding the preset range include: When the severity exceeds the preset range and is at level one, adjust the pulse duration and / or pulse interval duration; When the severity exceeds the preset range and reaches level two, the discharge current value is adjusted to an abnormal adjustment current value, wherein the abnormal adjustment current value is less than or equal to 50% of the current discharge current value. When the severity level exceeds the preset range and reaches Level 3, adjust the discharge current value to the preset safe current value.

5. The pulse power supply control method as described in claim 4, characterized in that, The preset safe current value is 0A.

6. The pulse power supply control method as described in claim 3, characterized in that, The step of detecting whether the discharge current value and / or discharge voltage value are within a preset range also includes: Multiple discharge current values ​​are generated based on multiple data sources, including user-set base current values, dynamic current curves, abnormal adjustment current values, and preset safe current values. The discharge current value is then selected based on the following priority rules from highest to lowest: When the severity level exceeds the preset range to level three, the preset safe current value is output. When the severity of the abnormality exceeds the preset range and is at level two, the abnormal adjustment current value is output. When a dynamic current curve exists, output the dynamic current curve value; Output the base current value.

7. The pulse power supply control method as described in claim 1, characterized in that, In the step of detecting whether the discharge current value and / or discharge voltage value are within a preset range, when updating the second type of parameter during the pulse interval, the start of the time period for updating the second type of parameter is closer to the end of the previous pulse duration period than the start of the next pulse duration period.

8. The pulse power supply control method as described in claim 1, characterized in that, In the step of detecting whether the discharge current value and / or discharge voltage value are within a preset range, the discharge current value and the discharge voltage value are detected multiple times within a pulse duration.

9. The pulse power supply control method as described in claim 8, characterized in that, The step of detecting whether the discharge current value and / or discharge voltage value are within a preset range includes: The discharge current value and / or discharge voltage value are detected to exceed the preset range by a certain amount. The discharge current value exceeds the preset range by a comparison between the average of multiple detected discharge current values ​​and the preset range of discharge current. The discharge voltage value exceeds the preset range by a comparison between the average of multiple detected discharge voltage values ​​and the preset range of discharge voltage.

10. A pulse power supply control system, applied to electrical discharge machining, characterized in that, The electrical discharge machining includes multiple machining parameters, and the control system of the pulse power supply drives the power device according to any one of the pulse power supply control methods in claims 1 to 9. The control system of the pulse power supply includes: A pulse generation module is connected to the power device. The pulse generation module is used to generate a discharge pulse signal according to multiple processing parameters and drive the power device to output a current control signal. A status detection module is used to detect the discharge current value and / or discharge voltage value of the discharge gap of the power device; The signal path is adjusted and connected between the state detection module and the pulse generation module to receive a second type of parameter from multiple processing parameters and control the updating of the second type of parameter; and, The parameter management module has a cache unit, which is used to cache the second type of parameters among multiple processing parameters. The parameter management module is connected to the status detection module and the pulse generation module respectively, and controls the timing of loading or updating the processing parameters in the cache unit according to the type of processing parameters and the current processing stage. The pulse generation module includes an arbitration unit. If the discharge current value and / or discharge voltage value are within a preset range, the arbitration unit switches to connect with the parameter management module so that the second type of parameter to be updated is stored in the cache unit and updated only during the pulse interval. If the discharge current value and / or discharge voltage value exceed the preset range, the arbitration unit switches to connect with the adjustment signal path and updates the second type of parameter during the pulse duration.

11. The control system for the pulse power supply as described in claim 10, characterized in that, The pulse generation module, the status detection module, the adjustment signal path, and the parameter management module are integrated on the same substrate.

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