阅读说明：本技术 可调速驱动设备的电压暂降耐受能力检测方法、装置 (voltage sag tolerance capability detection method and device of speed-adjustable driving equipment ) 是由 周凯 莫文雄 许中 马智远 郭倩雯 饶毅 栾乐 叶石丰 张群峰 崔晓飞 覃煜 于 2019-08-20 设计创作，主要内容包括：本申请涉及一种可调速驱动设备的电压暂降耐受能力检测方法、装置、计算机设备和存储介质。其中,可调速驱动设备的电压暂降耐受能力检测方法包括：通过建模分析计算各工况下可调速驱动设备的测试参数,根据所述测试参数确定所述可调速驱动设备的VTC曲线的膝点；根据所述可调速驱动设备在各个工况下对应的膝点分别在相应工况下对所述可调速驱动设备进行多次测试,直至测试获得的VTC曲线达到预设条件；根据达到预设条件的VTC曲线确定所述可调速驱动设备的电压暂降耐受能力。采用本方法能够高效地检测可调速驱动设备的电压暂降耐受能力。(The application relates to a voltage sag tolerance capability detection method and device of speed-adjustable driving equipment, computer equipment and a storage medium. The voltage sag tolerance detection method of the speed-adjustable driving equipment comprises the following steps: calculating test parameters of the speed-adjustable driving equipment under various working conditions through modeling analysis, and determining knee points of a VTC curve of the speed-adjustable driving equipment according to the test parameters; testing the speed-adjustable driving equipment for multiple times under corresponding working conditions according to the corresponding knee points of the speed-adjustable driving equipment under each working condition until a VTC curve obtained by the test reaches a preset condition; and determining the voltage sag tolerance capacity of the speed-adjustable driving equipment according to the VTC curve reaching the preset condition. By adopting the method, the voltage sag tolerance capability of the speed-adjustable driving equipment can be efficiently detected.)

1. A method for detecting voltage sag tolerance capability of a speed-adjustable driving device, the method comprising:

Calculating test parameters of the speed-adjustable driving equipment under various working conditions through modeling analysis, and determining knee points of a VTC curve of the speed-adjustable driving equipment according to the test parameters;

Testing the speed-adjustable driving equipment for multiple times under corresponding working conditions according to the corresponding knee points of the speed-adjustable driving equipment under each working condition until a VTC curve obtained by the test reaches a preset condition;

and determining the voltage sag tolerance capacity of the speed-adjustable driving equipment according to the VTC curve reaching the preset condition.

2. The method for detecting the voltage sag tolerance capability of the speed-adjustable driving device according to claim 1, wherein the working conditions comprise three-phase voltage supply working conditions; the test parameters under the three-phase voltage power supply working condition comprise a low-voltage tolerance threshold value and a disturbance duration threshold value.

3. The method for detecting the voltage sag tolerance capability of the speed-adjustable driving device according to claim 2, wherein the obtaining of the low voltage tolerance threshold comprises:

acquiring a direct-current link under-voltage protection setting value of the speed-adjustable driving equipment, substituting the direct-current link under-voltage protection setting value into a first amplitude calculation formula corresponding to a three-phase voltage power supply working condition, and calculating the critical amplitude of the speed-adjustable driving equipment under-voltage protection under symmetrical sag; the first magnitude calculation formula includes:

Wherein, V_3th-Vrepresents the critical amplitude value V of the undervoltage protection of the speed-adjustable driving equipment under the condition of symmetrical sag_DCthRepresenting an undervoltage protection setting value of a direct current link;

Acquiring a rated value of direct current voltage of the speed-adjustable driving device and a maximum instantaneous value of charging current during sag recovery, and substituting the rated value of direct current voltage and the maximum instantaneous value of charging current during sag recovery into a second amplitude calculation formula corresponding to a three-phase voltage power supply working condition to calculate a critical sag amplitude of the speed-adjustable driving device for triggering overcurrent protection during symmetrical sag recovery; the second magnitude calculation formula includes:

wherein, V_3th-IA critical sag amplitude, V, representing the trigger of overcurrent protection during symmetrical sag recovery_DCnRepresenting a nominal value of DC voltage, Δ i_maxThe maximum instantaneous value of the charging current during the recovery of the temporary drop is represented, L represents the inductance in the direct-current link of the motor frequency converter, and C represents the capacitance in the direct-current link of the motor frequency converter;

And determining the critical sag amplitude value for triggering the overcurrent protection when the symmetrical sag is recovered and the critical sag amplitude value for triggering the overcurrent protection when the symmetrical sag is recovered as the low-voltage tolerance threshold value.

4. the method for detecting voltage sag tolerance capability of a speed-adjustable driving device according to claim 1, wherein the operating condition comprises a single-phase voltage supply operating condition; the test parameters under the single-phase voltage power supply working condition comprise a disturbance duration time threshold of single-phase protection; the determination formula of the disturbance duration threshold of the single-phase protection comprises the following steps:

wherein, T_xDisturbance duration threshold, T, representing single phase protection_pulRepresenting a half-wave period, V_DCthindicating the DC link undervoltage protection setting value, V_LPrepresenting the peak of the line voltage pulse.

5. The method for detecting voltage sag tolerance capability of a speed-adjustable driving device according to claim 1, wherein the operating condition comprises a two-phase voltage supply operating condition; the test parameters under the two-phase voltage power supply working condition comprise a low-voltage tolerance threshold value and a disturbance duration threshold value.

6. The method for detecting the voltage sag tolerance capability of the speed-adjustable driving device according to claim 5, wherein the obtaining of the low voltage tolerance threshold comprises:

Acquiring a peak value and a phase voltage rated value of the voltage of the non-sag phase line of the speed-adjustable driving equipment;

Respectively calculating the undervoltage protection critical amplitude and the overcurrent protection critical amplitude of the speed-adjustable driving equipment under the condition of two-phase temporary drop according to the peak value of the voltage containing the non-temporary drop phase line and the phase voltage rated value;

and determining the larger value of the undervoltage protection critical amplitude and the overcurrent protection critical amplitude under the two-phase temporary drop as the low-voltage tolerance threshold.

7. The method for detecting the voltage sag tolerance capability of the speed-adjustable driving device according to any one of claims 1 to 6, wherein the step of testing the speed-adjustable driving device for a plurality of times under corresponding working conditions according to the knee point corresponding to the speed-adjustable driving device under each working condition until the VTC curve obtained by the test reaches a preset condition comprises:

under each working condition, setting an initial knee point amplitude according to a corresponding knee point, performing vertical cross stepping setting according to a preset amplitude step length, and determining a real-time knee point amplitude of each test;

And carrying out sag test on the speed-adjustable driving equipment according to each real-time knee point amplitude cycle until the equipment fails, and obtaining a VTC curve reaching a preset condition.

8. an apparatus for detecting voltage sag tolerance of a speed-adjustable driving device, the apparatus comprising:

The calculation module is used for calculating the test parameters of the speed-adjustable driving equipment under each working condition through modeling analysis and determining the knee point of the VTC curve of the speed-adjustable driving equipment according to the test parameters;

The testing module is used for testing the speed-adjustable driving equipment for multiple times under corresponding working conditions according to the corresponding knee points of the speed-adjustable driving equipment under each working condition until a VTC curve obtained by testing reaches a preset condition;

And the determining module is used for determining the voltage sag tolerance capacity of the speed-adjustable driving equipment according to the VTC curve reaching the preset condition.

9. A computer device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor when executing the computer program implements the steps of the voltage sag tolerance capability detection method of the adjustable speed drive device according to any one of claims 1 to 7.

10. a computer-readable storage medium, on which a computer program is stored, which, when being executed by a processor, carries out the steps of the voltage sag tolerance capability detection method of the adjustable speed drive apparatus according to any one of claims 1 to 7.

Technical Field

the present application relates to the field of electronic technologies, and in particular, to a method and an apparatus for detecting voltage sag tolerance of a speed-adjustable driving device, a computer device, and a storage medium.

Background

At present, research aiming at the sag tolerance capability of an adjustable speed driving device (ASD) is mainly developed around a voltage sag tolerance curve (VTC) test, and a traditional standard test method includes methods of top-down, left-right, closed and the like. The testing method can basically meet the testing requirements of various sensitive devices, but lacks pertinence, and can not solve the contradiction between testing precision and testing efficiency. The binary test method improves the efficiency of the test under the conditions of small step length and high precision to a certain extent, but a plurality of tests are still required. For ASD equipment, the influence of factors such as sag types and load levels needs to be considered, the test conditions are more, the motor reset needs to be ensured after one-time test, and the test period is long. It can be seen that the conventional ASD sag tolerance testing technology has the problem of low efficiency.

Disclosure of Invention

in view of the above, it is necessary to provide a voltage sag tolerance detection method and apparatus for a speed-adjustable driving device, a computer device, and a storage medium, which can improve sag tolerance detection efficiency.

A method of voltage sag tolerance detection of a speed-adjustable drive device, the method comprising:

Calculating test parameters of the speed-adjustable driving equipment under various working conditions through modeling analysis, and determining knee points of a VTC curve of the speed-adjustable driving equipment according to the test parameters;

Testing the speed-adjustable driving equipment for multiple times under corresponding working conditions according to the corresponding knee points of the speed-adjustable driving equipment under each working condition until a VTC curve obtained by the test reaches a preset condition;

And determining the voltage sag tolerance capacity of the speed-adjustable driving equipment according to the VTC curve reaching the preset condition.

In one embodiment, the operating conditions include three-phase voltage supply operating conditions; the test parameters under the three-phase voltage power supply working condition comprise a low-voltage tolerance threshold value and a disturbance duration threshold value.

as an embodiment, the obtaining of the low pressure tolerance threshold includes:

acquiring a direct-current link under-voltage protection setting value of the speed-adjustable driving equipment, substituting the direct-current link under-voltage protection setting value into a first amplitude calculation formula corresponding to a three-phase voltage power supply working condition, and calculating the critical amplitude of the speed-adjustable driving equipment under-voltage protection under symmetrical sag; the first magnitude calculation formula includes:

Wherein, V_3th-Vrepresents the critical amplitude value V of the undervoltage protection of the speed-adjustable driving equipment under the condition of symmetrical sag_DCthrepresenting an undervoltage protection setting value of a direct current link;

Acquiring a rated value of direct current voltage of the speed-adjustable driving device and a maximum instantaneous value of charging current during sag recovery, and substituting the rated value of direct current voltage and the maximum instantaneous value of charging current during sag recovery into a second amplitude calculation formula corresponding to a three-phase voltage power supply working condition to calculate a critical sag amplitude of the speed-adjustable driving device for triggering overcurrent protection during symmetrical sag recovery; the second magnitude calculation formula includes:

Wherein, V_3th-IA critical sag amplitude, V, representing the trigger of overcurrent protection during symmetrical sag recovery_DCnrepresenting a nominal value of DC voltage, Δ i_maxThe maximum instantaneous value of the charging current during the recovery of the temporary drop is represented, L represents the inductance in the direct-current link of the motor frequency converter, and C represents the capacitance in the direct-current link of the motor frequency converter;

and determining the critical sag amplitude value for triggering the overcurrent protection when the symmetrical sag is recovered and the critical sag amplitude value for triggering the overcurrent protection when the symmetrical sag is recovered as the low-voltage tolerance threshold value.

in one embodiment, the operating condition comprises a single-phase voltage supply operating condition; the test parameters under the single-phase voltage power supply working condition comprise a disturbance duration time threshold of single-phase protection; the determination formula of the disturbance duration threshold of the single-phase protection comprises the following steps:

wherein, T_xdisturbance duration threshold, T, representing single phase protection_pulRepresenting a half-wave period, V_DCthIndicating the DC link undervoltage protection setting value, V_LPrepresenting the peak of the line voltage pulse.

in one embodiment, the operating condition comprises a two-phase voltage supply operating condition; the test parameters under the two-phase voltage power supply working condition comprise a low-voltage tolerance threshold value and a disturbance duration threshold value.

as an embodiment, the obtaining of the low pressure tolerance threshold includes:

acquiring a peak value and a phase voltage rated value of the voltage of the non-sag phase line of the speed-adjustable driving equipment;

respectively calculating the undervoltage protection critical amplitude and the overcurrent protection critical amplitude of the speed-adjustable driving equipment under the condition of two-phase temporary drop according to the peak value of the voltage containing the non-temporary drop phase line and the phase voltage rated value;

And determining the larger value of the undervoltage protection critical amplitude and the overcurrent protection critical amplitude under the two-phase temporary drop as the low-voltage tolerance threshold.

in an embodiment, the performing, for the adjustable speed driving device, multiple tests on the adjustable speed driving device under corresponding working conditions according to knee points corresponding to the adjustable speed driving device under each working condition until a VTC curve obtained by the tests reaches a preset condition includes:

Under each working condition, setting an initial knee point amplitude according to a corresponding knee point, performing vertical cross stepping setting according to a preset amplitude step length, and determining a real-time knee point amplitude of each test;

And carrying out sag test on the speed-adjustable driving equipment according to each real-time knee point amplitude cycle until the equipment fails, and obtaining a VTC curve reaching a preset condition.

an apparatus for detecting voltage sag tolerance capability of a speed-adjustable drive device, the apparatus comprising:

the calculation module is used for calculating the test parameters of the speed-adjustable driving equipment under each working condition through modeling analysis and determining the knee point of the VTC curve of the speed-adjustable driving equipment according to the test parameters;

The testing module is used for testing the speed-adjustable driving equipment for multiple times under corresponding working conditions according to the corresponding knee points of the speed-adjustable driving equipment under each working condition until a VTC curve obtained by testing reaches a preset condition;

and the determining module is used for determining the voltage sag tolerance capacity of the speed-adjustable driving equipment according to the VTC curve reaching the preset condition.

a computer device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor implements the steps of the voltage sag tolerance capability detection method of the speed-adjustable driving device of any one of the above embodiments when executing the computer program.

a computer-readable storage medium, on which a computer program is stored, which, when being executed by a processor, implements the steps of the voltage sag tolerance capability detection method of the adjustable speed drive device of any one of the above embodiments.

According to the voltage sag tolerance detection method and device of the speed-adjustable driving equipment, the computer equipment and the storage medium, the test parameters of the speed-adjustable driving equipment under each working condition are calculated through modeling analysis, the knee point of the VTC curve of the speed-adjustable driving equipment is determined according to the test parameters, the speed-adjustable driving equipment is tested for multiple times under each working condition according to the corresponding knee point until the VTC curve obtained through testing reaches the preset condition, the voltage sag tolerance of the speed-adjustable driving equipment is determined according to the VTC curve reaching the preset condition, and the purpose of efficiently detecting the voltage sag tolerance of the speed-adjustable driving equipment is achieved.

Drawings

FIG. 1 is a schematic diagram of a test platform according to one embodiment;

FIG. 2 is a schematic flow chart illustrating a method for detecting voltage sag tolerance of an adjustable speed drive according to an embodiment;

FIG. 3 is a schematic illustration of a VTC curve of an embodiment;

FIG. 4 is a block diagram of a voltage sag tolerance detection apparatus of an embodiment of a variable speed drive;

FIG. 5 is a diagram illustrating an internal structure of a computer device according to an embodiment.

Detailed Description

in order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.

The voltage sag tolerance detection method for the speed-adjustable driving equipment can be applied to detection equipment for detecting the voltage sag tolerance of the speed-adjustable driving equipment, the detection equipment can be connected with the test platform shown in fig. 1 and can also be arranged on the test platform, the test platform is controlled to carry out voltage sag tolerance test work on the speed-adjustable driving equipment, and a test result is obtained so as to detect the voltage sag tolerance of the speed-adjustable driving equipment. In the voltage sag tolerance detection process of the speed-adjustable driving equipment, the knee point position estimation is the key for drawing the VTC of the equipment. The corresponding ASD tolerance assessment scheme mainly comprises a test, a three-phase symmetrical sag tolerance assessment, a single-phase sag tolerance assessment and a two-phase sag tolerance assessment, wherein the assessment results of each stage are knee point characteristic values (critical duration and amplitude) or judgment results of whether follow-up tests are required. The adopted test platform is built according to relevant standards, as shown in fig. 1, after the wiring is ensured to be correct, the ASD can be started to enable the motor to enter a preset working condition; and a programmable power supply can be adopted to generate a symmetrical sag with the amplitude value of 0, the sag duration time is gradually increased until the equipment fails, and the power supply interruption tolerance time of the ASD under different motor load amounts is obtained.

The detection equipment can calculate the test parameters of the speed-adjustable driving equipment under each working condition through modeling analysis, determine the knee point of the VTC curve of the speed-adjustable driving equipment according to the test parameters, and test the speed-adjustable driving equipment for multiple times under the corresponding working conditions according to the corresponding knee point of the speed-adjustable driving equipment under each working condition until the VTC curve obtained by the test reaches the preset condition; determining the voltage sag tolerance capacity of the speed-adjustable driving equipment according to the VTC curve reaching the preset condition; so as to quickly and efficiently detect the voltage sag tolerance capability of the speed-adjustable driving device.

In one embodiment, as shown in fig. 2, there is provided a voltage sag tolerance detection method for a speed-adjustable driving device, including the following steps:

s210, calculating test parameters of the speed-adjustable driving equipment under each working condition through modeling analysis, and determining knee points of a VTC curve of the speed-adjustable driving equipment according to the test parameters;

The test parameters comprise parameters such as a low pressure tolerance threshold value and/or a disturbance duration threshold value. The test conditions of the speed-adjustable driving device can comprise a three-phase voltage power supply condition, a two-phase voltage power supply electrician and a single-phase voltage power supply electrician. Under each working condition, test parameters such as a low-pressure tolerance threshold value and/or a disturbance duration threshold value can be calculated according to configuration parameters of the speed-adjustable driving device.

Specifically, after the working conditions to be tested are determined, a possible low-pressure tolerance threshold value and a disturbance duration threshold value of the ASD under each working condition are calculated preferentially through modeling analysis, and a knee point of a VTC curve of the ASD is determined (the content of determining the knee point is the key and core content of the whole method). After the knee point is determined, the approximate position of the 'rectangular' VTC curve is determined, and on the basis, the real VTC of the tested device can be tested more quickly.

S230, testing the speed-adjustable driving equipment for multiple times under corresponding working conditions according to the corresponding knee points of the speed-adjustable driving equipment under each working condition until a VTC curve obtained by testing reaches a preset condition;

The steps can be respectively carried out for multiple times of cyclic tests on the speed-adjustable driving equipment by adopting the knee points corresponding to the corresponding working conditions under each working condition until the VTC curve obtained by the tests reaches the preset condition. The preset conditions may include conditions that the amplitude corresponding to the upper boundary of the VTC curve meets the corresponding requirements, and the like, so that the obtained VTC curve may accurately represent the voltage sag tolerance of the speed-adjustable driving device.

And S250, determining the voltage sag tolerance capacity of the speed-adjustable driving equipment according to the VTC curve reaching the preset condition.

The above steps can determine the approximate position of the actual VTC of the speed-adjustable driving device according to the obtained VTC curve, so as to detect the voltage sag tolerance capability of the speed-adjustable driving device accordingly.

According to the voltage sag tolerance detection method of the speed-adjustable driving equipment, the test parameters of the speed-adjustable driving equipment under each working condition are calculated through modeling analysis, the knee points of the VTC curve of the speed-adjustable driving equipment are determined according to the test parameters, the speed-adjustable driving equipment is tested for multiple times under each working condition according to the corresponding knee points until the VTC curve obtained through testing reaches the preset condition, the voltage sag tolerance of the speed-adjustable driving equipment is determined according to the VTC curve reaching the preset condition, and the purpose of efficiently detecting the voltage sag tolerance of the speed-adjustable driving equipment is achieved.

in one embodiment, the operating conditions include three-phase voltage supply operating conditions; the test parameters under the three-phase voltage power supply working condition comprise a low-voltage tolerance threshold (also called as a three-phase symmetrical sag critical amplitude V) and a disturbance duration threshold (also called as a critical duration of symmetrical sag undervoltage protection).

In the three-phase symmetrical sag tolerance capability evaluation process of the speed-adjustable driving equipment, the critical duration time T of the undervoltage protection under symmetrical sag can be obtained_3th(i.e., the perturbation duration threshold) and associated parameters.

As an embodiment, under the three-phase voltage power supply condition, the obtaining process of the low voltage tolerance threshold value includes:

Acquiring a direct-current link under-voltage protection setting value of the speed-adjustable driving equipment, substituting the direct-current link under-voltage protection setting value into a first amplitude calculation formula corresponding to a three-phase voltage power supply working condition, and calculating the critical amplitude of the speed-adjustable driving equipment under-voltage protection under symmetrical sag; the first magnitude calculation formula includes:

Wherein, V_3th-VRepresents the critical amplitude value V of the undervoltage protection of the speed-adjustable driving equipment under the condition of symmetrical sag_DCthrepresenting an undervoltage protection setting value of a direct current link; p_Lrepresenting the load power, and C representing the capacitance of the direct current link;

Acquiring a rated value of direct current voltage of the speed-adjustable driving device and a maximum instantaneous value of charging current during sag recovery, and substituting the rated value of direct current voltage and the maximum instantaneous value of charging current during sag recovery into a second amplitude calculation formula corresponding to a three-phase voltage power supply working condition to calculate a critical sag amplitude of the speed-adjustable driving device for triggering overcurrent protection during symmetrical sag recovery; the second magnitude calculation formula includes:

wherein, V_3th-IA critical sag amplitude, V, representing the trigger of overcurrent protection during symmetrical sag recovery_DCnRepresenting a nominal value of DC voltage, Δ i_maxThe maximum instantaneous value of the charging current during the recovery of the temporary drop is represented, L represents the inductance in the direct-current link of the motor frequency converter, and C represents the capacitance in the direct-current link of the motor frequency converter;

determining the critical sag amplitude value for triggering the overcurrent protection when the symmetrical sag is recovered and the critical sag amplitude value for triggering the overcurrent protection when the symmetrical sag is recovered as the low-voltage tolerance threshold value, namely a low-voltage tolerance threshold value V_3thcomprises the following steps: v_3th＝max(V_3th-V,V_3th-I)。

the embodiment can accurately acquire the test parameter of the low-voltage tolerance threshold under the three-phase voltage power supply working condition.

In one embodiment, the operating condition comprises a single-phase voltage supply operating condition; the test parameters under the single-phase voltage power supply working condition comprise a disturbance duration threshold of single-phase protection (which can also be called as the characteristic duration of the single-phase protection); the determination formula of the disturbance duration threshold of the single-phase protection comprises the following steps:

wherein, T_xDisturbance duration threshold, T, representing single phase protection_pulRepresenting a half-wave period, V_DCthindicating the DC link undervoltage protection setting value, V_LPRepresenting the peak of the line voltage pulse.

In particular, T_pulRepresents the half-wave period, and the normal half-wave period is 10ms under the power frequency of 50 Hz. For the speed-adjustable driving device, if the critical duration T of the under-voltage protection is symmetrically and temporarily reduced_3thgreater than T_xThe device temporarily de-immunized to monophasic. If the critical duration T of the under-voltage protection is symmetrically temporarily decreased_3thLess than T_xFurther testing may be performed to obtain VTC curves. ASD are typically immunised to monophasic suspensions without taking into account phase-loss protection.

in one embodiment, the operating condition comprises a two-phase voltage supply operating condition; the test parameters under the two-phase voltage supply condition comprise a low voltage tolerance threshold (also called a two-phase symmetric sag critical amplitude) and a disturbance duration threshold (also called a two-phase voltage sag critical duration).

the critical duration of the two-phase voltage sag (i.e., the disturbance duration threshold) can be determined by the critical duration T of the symmetric sag under-voltage protection_3thAnd (6) estimating.

In one embodiment, the obtaining process of the low voltage tolerance threshold value under the two-phase voltage power supply condition comprises the following steps:

Acquiring a peak value and a phase voltage rated value of the voltage of the non-sag phase line of the speed-adjustable driving equipment;

Respectively calculating the undervoltage protection critical amplitude and the overcurrent protection critical amplitude of the speed-adjustable driving equipment under the condition of two-phase temporary drop according to the peak value of the voltage containing the non-temporary drop phase line and the phase voltage rated value;

And determining the larger value of the undervoltage protection critical amplitude and the overcurrent protection critical amplitude under the two-phase temporary drop as the low-voltage tolerance threshold.

Specifically, the under-voltage protection critical amplitude of the speed-adjustable driving device under the two-phase sag can be determined by the following formula:

Wherein, V_2th-Vrepresenting the critical amplitude, V, of the undervoltage protection for a two-phase sag_sLPShowing the peak value of the voltage of the phase line containing the non-sag (in the two-phase sag, the amplitude of a certain phase voltage is a rated value, so that two line voltages in three line voltage components contain the non-sag phase), V_nPRepresenting the phase voltage rating and alpha representing the calculated angle.

V_sLPCan be obtained as follows:

In the formula, V_DCthrepresenting an undervoltage protection setting value of a direct current link; p_LRepresenting the load power.

a can pass through the pair V_sLPThe degree of degradation is obtained by linear estimation, such as determined by:

In the formula, V_LPRepresenting the peak of the line voltage pulse.

Δ T may be determined by:

in the formula, V_DCnIndicating a rated value of the DC voltage, V_DCthindicating the DC link undervoltage protection setting value, T_pulAnd K represents a time error correction coefficient and is used for representing the error of the active correction model, and the value range can be 0.8-0.9.

in particular, the low pressure resistance threshold V_2thcomprises the following steps: v_2th＝max(V_2th-V,V_2th-I)。

Optionally, after obtaining the test parameters under each operating condition, a rectangular VTC curve may be drawn with reference to each load level and knee point under each sag type, so as to approximately reflect the ASD sag tolerance capability, guide further test work, and the like.

In an embodiment, the performing, for the adjustable speed driving device, multiple tests on the adjustable speed driving device under corresponding working conditions according to knee points corresponding to the adjustable speed driving device under each working condition until a VTC curve obtained by the tests reaches a preset condition includes:

Under each working condition, setting an initial knee point amplitude according to a corresponding knee point, performing vertical cross stepping setting according to a preset amplitude step length, and determining a real-time knee point amplitude of each test;

And carrying out sag test on the speed-adjustable driving equipment according to each real-time knee point amplitude cycle until the equipment fails, and obtaining a VTC curve reaching a preset condition.

In this embodiment, the real-time knee point amplitude of each test may be increased and decreased according to a preset amplitude step size on the basis of the initial knee point amplitude, so as to determine a plurality of real-time knee point amplitudes using the initial knee point amplitude as a middle value, and more accurately test the speed-adjustable driving device.

In one example, the obtained evaluation result (knee point corresponding to the speed-adjustable driving device under each working condition) can be used as a reference VTC for guiding development of test work, optimizing a step size control strategy, reducing test steps, improving test efficiency and reducing the influence suffered by the device. The specific scheme can comprise:

step 1: adjusting a sag source of the test platform, setting sag duration as a test maximum value (such as 1s), carrying out vertical cross stepping setting according to a preset amplitude step length by taking the knee point amplitude obtained by evaluation under the corresponding load level and sag type as a basis, and generating test sag until equipment fails to work so as to determine the amplitude corresponding to the upper boundary of the VTC.

Step 2: and setting the sag duration according to the knee point coordinates, gradually increasing the sag amplitude to the minimum value until equipment fails, and recording the duration when the equipment fails. And increasing the amplitude according to a preset step length, and repeating the operation until the amplitude corresponding to the upper boundary of the VTC.

The specific test procedure can be seen with reference to fig. 3, in which fig. 3, the abscissa represents the duration and the ordinate represents the amplitude. Because the VTC obtained by evaluation reflects the approximate position of the actual VTC of the equipment, the test based on the evaluation result is more targeted, the required test steps are smaller, the test efficiency is improved, and the influence of the tested equipment is reduced. For the evaluation result with high coincidence, the position of the VTC curve point can be determined through a further test, so that a tester is prompted to further reduce the control step length to obtain a more accurate result.

on the basis of researching the ASD sag response mechanism, the embodiment provides a method for determining a VTC profile (or a knee point of a voltage sag tolerance curve) based on frequency converter key parameters and test results, and tests are performed with the VTC profile as a guidance basis, so that the following technical effects can be achieved: the method can provide a preliminary reference for user equipment selection; the method can provide an ASD (anaerobic baffling) tolerance capacity assessment means for users without VTC (VTC test) conditions; for a relevant testing mechanism, the obtained evaluation result can be used as a reference VTC for guiding the development of testing work, optimizing the step length control strategy, reducing the testing steps, improving the testing efficiency and reducing the influence suffered by equipment. The voltage sag tolerance detection method of the speed-adjustable driving equipment is suitable for different load quantities, ASD undervoltage protection and overcurrent protection are considered, and the method for evaluating the VTC knee point of the equipment in different types of sag is obtained based on a small amount of test data.

It should be understood that, although the steps in the flowchart of fig. 2 are shown in order as indicated by the arrows, the steps are not necessarily performed in order as indicated by the arrows. The steps are not performed in the exact order shown and described, and may be performed in other orders, unless explicitly stated otherwise. Moreover, at least a portion of the steps in fig. 2 may include multiple sub-steps or multiple stages that are not necessarily performed at the same time, but may be performed at different times, and the order of performance of the sub-steps or stages is not necessarily sequential, but may be performed in turn or alternately with other steps or at least a portion of the sub-steps or stages of other steps.

in one embodiment, as shown in fig. 4, there is provided a voltage sag tolerance detection apparatus of a speed-adjustable driving device, including:

The calculating module 210 is configured to calculate a test parameter of the speed-adjustable driving device under each working condition through modeling analysis, and determine a knee point of a VTC curve of the speed-adjustable driving device according to the test parameter;

The testing module 230 is configured to perform multiple tests on the speed-adjustable driving device under corresponding working conditions according to corresponding knee points of the speed-adjustable driving device under each working condition until a VTC curve obtained through the tests reaches a preset condition;

A determining module 250, configured to determine a voltage sag tolerance capability of the speed-adjustable driving device according to the VTC curve that reaches a preset condition.

In one embodiment, the operating conditions include three-phase voltage supply operating conditions; the test parameters under the three-phase voltage power supply working condition comprise a low-voltage tolerance threshold value and a disturbance duration threshold value.

As an embodiment, the computing module is further to:

Acquiring a direct-current link under-voltage protection setting value of the speed-adjustable driving equipment, substituting the direct-current link under-voltage protection setting value into a first amplitude calculation formula corresponding to a three-phase voltage power supply working condition, and calculating the critical amplitude of the speed-adjustable driving equipment under-voltage protection under symmetrical sag; the first magnitude calculation formula includes:

wherein, V_3th-VRepresents the critical amplitude value V of the undervoltage protection of the speed-adjustable driving equipment under the condition of symmetrical sag_DCthRepresenting an undervoltage protection setting value of a direct current link;

Acquiring a rated value of direct current voltage of the speed-adjustable driving device and a maximum instantaneous value of charging current during sag recovery, and substituting the rated value of direct current voltage and the maximum instantaneous value of charging current during sag recovery into a second amplitude calculation formula corresponding to a three-phase voltage power supply working condition to calculate a critical sag amplitude of the speed-adjustable driving device for triggering overcurrent protection during symmetrical sag recovery; the second magnitude calculation formula includes:

Wherein, V_3th-IA critical sag amplitude, V, representing the trigger of overcurrent protection during symmetrical sag recovery_DCnrepresenting a nominal value of DC voltage, Δ i_maxThe maximum instantaneous value of the charging current during the recovery of the temporary drop is represented, L represents the inductance in the direct-current link of the motor frequency converter, and C represents the capacitance in the direct-current link of the motor frequency converter;

And determining the critical sag amplitude value for triggering the overcurrent protection when the symmetrical sag is recovered and the critical sag amplitude value for triggering the overcurrent protection when the symmetrical sag is recovered as the low-voltage tolerance threshold value.

In one embodiment, the operating condition comprises a single-phase voltage supply operating condition; the test parameters under the single-phase voltage power supply working condition comprise a disturbance duration time threshold of single-phase protection; the determination formula of the disturbance duration threshold of the single-phase protection comprises the following steps:

Wherein, T_xdisturbance duration threshold, T, representing single phase protection_pulRepresenting a half-wave period, V_DCthindicating the DC link undervoltage protection setting value, V_LPRepresenting the peak of the line voltage pulse.

In one embodiment, the operating condition comprises a two-phase voltage supply operating condition; the test parameters under the two-phase voltage power supply working condition comprise a low-voltage tolerance threshold value and a disturbance duration threshold value.

As an embodiment, the above calculation module is further configured to:

Acquiring a peak value and a phase voltage rated value of the voltage of the non-sag phase line of the speed-adjustable driving equipment;

Respectively calculating the undervoltage protection critical amplitude and the overcurrent protection critical amplitude of the speed-adjustable driving equipment under the condition of two-phase temporary drop according to the peak value of the voltage containing the non-temporary drop phase line and the phase voltage rated value;

And determining the larger value of the undervoltage protection critical amplitude and the overcurrent protection critical amplitude under the two-phase temporary drop as the low-voltage tolerance threshold.

In one embodiment, the test module is further configured to:

Under each working condition, setting an initial knee point amplitude according to a corresponding knee point, performing vertical cross stepping setting according to a preset amplitude step length, and determining a real-time knee point amplitude of each test;

and carrying out sag test on the speed-adjustable driving equipment according to each real-time knee point amplitude cycle until the equipment fails, and obtaining a VTC curve reaching a preset condition.

for specific limitations of the voltage sag tolerance detection apparatus of the speed-adjustable driving device, reference may be made to the above limitations of the voltage sag tolerance detection method of the speed-adjustable driving device, and details thereof are not repeated herein. The modules in the voltage sag tolerance detection device of the speed-adjustable driving equipment can be wholly or partially realized by software, hardware and a combination thereof. The modules can be embedded in a hardware form or independent from a processor in the computer device, and can also be stored in a memory in the computer device in a software form, so that the processor can call and execute operations corresponding to the modules.

In one embodiment, a computer device is provided, which may be a terminal, and its internal structure diagram may be as shown in fig. 5. The computer device includes a processor, a memory, a network interface, a display screen, and an input device connected by a system bus. Wherein the processor of the computer device is configured to provide computing and control capabilities. The memory of the computer device comprises a nonvolatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of an operating system and computer programs in the non-volatile storage medium. The network interface of the computer device is used for communicating with an external terminal through a network connection. The computer program is executed by a processor to implement a method of voltage sag tolerance detection for a speed-adjustable drive device. The display screen of the computer equipment can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer equipment can be a touch layer covered on the display screen, a key, a track ball or a touch pad arranged on the shell of the computer equipment, an external keyboard, a touch pad or a mouse and the like.

Those skilled in the art will appreciate that the architecture shown in fig. 5 is merely a block diagram of some of the structures associated with the disclosed aspects and is not intended to limit the computing devices to which the disclosed aspects apply, as particular computing devices may include more or less components than those shown, or may combine certain components, or have a different arrangement of components.

Based on the examples described above, in one embodiment, a computer device is further provided, where the computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor executes the computer program to implement the voltage sag tolerance capability detection method of the adjustable speed drive device in any one of the embodiments described above.

According to the computer equipment, the purpose of efficiently detecting the voltage sag tolerance capability of the speed-adjustable driving equipment can be achieved through the computer program running on the processor.

it will be understood by those skilled in the art that all or part of the processes in the methods of the above embodiments may be implemented by a computer program, which may be stored in a non-volatile computer-readable storage medium, and in the embodiments of the present invention, the program may be stored in the storage medium of a computer system and executed by at least one processor in the computer system, so as to implement the processes of the embodiments including the voltage sag tolerance capability detection method of the above speed-adjustable drive device. The storage medium may be a magnetic disk, an optical disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), or the like.

Accordingly, in an embodiment, a computer readable storage medium is also provided, on which a computer program is stored, wherein the program, when executed by a processor, implements the voltage sag tolerance capability detection method of any one of the adjustable speed drive devices as described in the embodiments above.

the computer-readable storage medium described above, with its stored computer program, can improve the efficiency of detecting the voltage sag tolerance capability of the speed-adjustable drive device.

It will be understood by those skilled in the art that all or part of the processes of the methods of the embodiments described above can be implemented by hardware instructions of a computer program, which can be stored in a non-volatile computer-readable storage medium, and when executed, can include the processes of the embodiments of the methods described above. Any reference to memory, storage, database, or other medium used in the embodiments provided herein may include non-volatile and/or volatile memory, among others. Non-volatile memory can include read-only memory (ROM), Programmable ROM (PROM), Electrically Programmable ROM (EPROM), Electrically Erasable Programmable ROM (EEPROM), or flash memory. Volatile memory can include Random Access Memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in a variety of forms such as Static RAM (SRAM), Dynamic RAM (DRAM), Synchronous DRAM (SDRAM), Double Data Rate SDRAM (DDRSDRAM), Enhanced SDRAM (ESDRAM), Synchronous Link DRAM (SLDRAM), Rambus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

The technical features of the above embodiments can be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the above embodiments are not described, but should be considered as the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

It should be noted that the terms "first \ second \ third" referred to in the embodiments of the present application merely distinguish similar objects, and do not represent a specific ordering for the objects, and it should be understood that "first \ second \ third" may exchange a specific order or sequence when allowed. It should be understood that "first \ second \ third" distinct objects may be interchanged under appropriate circumstances such that the embodiments of the application described herein may be implemented in an order other than those illustrated or described herein.

the terms "comprising" and "having" and any variations thereof in the embodiments of the present application are intended to cover non-exclusive inclusions. For example, a process, method, apparatus, product, or device that comprises a list of steps or modules is not limited to the listed steps or modules but may alternatively include other steps or modules not listed or inherent to such process, method, product, or device.

Reference herein to "a plurality" means two or more. "and/or" describes the association relationship of the associated objects, meaning that there may be three relationships, e.g., a and/or B, which may mean: a exists alone, A and B exist simultaneously, and B exists alone. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship.

The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.