CN103817404A - Manual electric arc welder three-phase electricity phase loss detection method and device - Google Patents

Abstract

The invention provides a manual electric arc welder three-phase electricity phase loss detection method and device. The method is applied to a manual electric arc welder three-phase electricity phase loss detection device comprising a power transformer. The power transformer is coupled with any two phases in three-phase supply in order to supply power to the manual electric arc welder three-phase electricity phase loss detection device. The method includes the steps of detecting a feedback current, and judging whether three-phase electricity loses phase according to the detected feedback current. According to the manual electric arc welder three-phase electricity phase loss detection method and device, multiple step-down transformers and phase loss detection circuits are not needed, the circuit structure is simplified, and the cost is saved.

Description

A kind of hand arc welding machine three-phase electric power open phase detection method and device

Technical field

The present invention relates to technical field of electricity, be specifically related to a kind of hand arc welding machine three-phase electric power open phase detection method and device.

Background technology

Along with popularizing of inversion welding machine and frequency converter, it is particularly important that its safety and reliability seems.Conventionally,, in the time that three phase mains equipment (hand arc welding machine) is worked, if phase shortage, two of operating current is met and is caused rectifier bridge electric current to increase, thereby makes heating serious, further burns rectifier bridge or phase-shifting transformer.Extremely turn round when the three-phase dispatch from foreign news agency phase shortage for fear of three phase mains equipment, just need to before using, detect whether phase shortage of three-phase dispatch from foreign news agency, to guarantee correctness and the integrality of three phase mains access phase sequence.

Traditional multiple step-down transformers of the general employing of hand arc welding machine three-phase electric power open phase detection scheme, as shown in Figure 1,3 step-down transformers UV, VW, UW phase of coupling power 11 respectively, and coordinate respectively UV phase detecting circuit 12, VW phase detecting circuit 13 and UW phase detecting circuit 14, realize light-coupled isolation, carry out U, V, the judgement of W three-phase dispatch from foreign news agency phase shortage.If UV phase detecting circuit 12 detects as high potential, judge and between UV, have voltage that i.e. phase shortage not, if UV phase detecting circuit 12 detects as electronegative potential, judges no-voltage, i.e. phase shortage between UV mutually.Accordingly, VW phase detecting circuit 13 and UW phase detecting circuit 14 also judge whether phase shortage in the same way.

But, in traditional hand arc welding machine three-phase electric power open phase detection scheme, need to whether could finally determine phase shortage in conjunction with the testing result of 3 testing circuits, therefore, need 3 step-down transformers to coordinate respectively 3 lack detection circuits to realize, circuit structure is complicated and unstable, and cost is high, is unsuitable for popularization.

Therefore, need a kind of hand arc welding machine three-phase electric power open phase detection scheme badly in order to solve the problems of the technologies described above.

Summary of the invention

The embodiment of the present invention provides a kind of hand arc welding machine three-phase electric power open phase detection method and device, in order to solve existing hand arc welding machine three-phase electric power open phase detection scheme circuit structure complexity, poor stability, problem that cost is high.

To achieve these goals, the embodiment of the present invention adopts following technological means:

The embodiment of the present invention provides a kind of hand arc welding machine three-phase electric power open phase detection method, be applied to the hand arc welding machine three-phase electric power open phase checkout gear that comprises power transformer, any two-phase in described power transformer coupling three phase mains, with thinking the power supply of hand arc welding machine three-phase electric power open phase checkout gear; Described method comprises:

Detect feedback current;

According to the feedback current detecting, judge whether phase shortage of three-phase electricity.

The embodiment of the present invention also provides a kind of hand arc welding machine three-phase electric power open phase checkout gear, comprise: detecting unit, control module and power transformer, any two-phase in described power transformer coupling three phase mains, with thinking the power supply of hand arc welding machine three-phase electric power open phase checkout gear;

Described detecting unit, connects described power transformer, for detection of feedback current;

Described control module, connects described detecting unit, for judge whether phase shortage of three-phase electricity according to feedback current.

Compared with prior art, the above embodiment of the present invention has following useful technique effect:

The hand arc welding machine three-phase electric power open phase detection scheme that the embodiment of the present invention provides, power transformer is coupled in to any two-phase in three phase mains, judge whether phase shortage of arc welder by detecting the variation of feedback current, without multiple step-down transformers and lack detection circuit are set, simplify circuit structure, cost-saving.

Accompanying drawing explanation

Fig. 1 is existing hand arc welding machine three-phase electric power open phase testing circuit connection diagram;

The hand arc welding machine three-phase electric power open phase checkout gear connection diagram that Fig. 2 provides for the embodiment of the present invention;

Fig. 3 a is current feedback waveform schematic diagram when phase shortage not;

One of feedback current waveform schematic diagram when Fig. 3 b is phase shortage;

Two of feedback current waveform schematic diagram when Fig. 3 c is phase shortage;

The feedback current waveform schematic diagram that Fig. 4 provides for the embodiment of the present invention three;

One of hand arc welding machine three-phase electric power open phase testing process schematic diagram that Fig. 5 provides for the embodiment of the present invention three;

Two of the hand arc welding machine three-phase electric power open phase testing process schematic diagram that Fig. 6 provides for the embodiment of the present invention three;

Three of the hand arc welding machine three-phase electric power open phase testing process schematic diagram that Fig. 7 provides for the embodiment of the present invention three;

Fig. 8 is the structural representation of hand arc welding machine three-phase electric power open phase checkout gear of the present invention.

The specific embodiment

The problems referred to above that exist for prior art, the embodiment of the present invention provides a kind of hand arc welding machine three-phase electric power open phase detection scheme, in order to simplify hardware circuit, cost-saving.Below in conjunction with accompanying drawing, the embodiment of the present invention is described in detail.

The embodiment of the present invention proposes one and realizes simple hand arc welding machine three-phase electric power open phase detection scheme, use any two-phase in three phase mains to provide electric power for hand arc welding machine, for example, using U phase and V is hand arc welding machine power supply mutually, when lacking U phase or V phase time, manual electric arc welding electromechanical source disconnects, and can not work, and does not just export accordingly.When lacking W phase time, do not affect supply of electric power and the output of hand arc welding machine, now, can utilize hand arc welding machine three-phase electric power open phase checkout gear, by the feedback current that detects hand arc welding machine, it is carried out to three-phase electric power open phase judgement.

In the situation that lacking W phase, feedback current is unstable, there will be following situation:

1, feedback current can be down to suddenly zero from normal value, produces usually said current interruption phenomenon;

2, feedback current fluctuation range is larger, and vibration frequency is higher.

The hand arc welding machine three-phase electric power open phase detection scheme that the embodiment of the present invention provides, can detect and judge for the feedback current of above-mentioned 2 kinds of situations.

Referring to Fig. 2; the hand arc welding machine three-phase electric power open phase checkout gear connection diagram providing for the embodiment of the present invention; the embodiment of the present invention is powered mutually and is described for example in order to the U phase in arc welder three phase mains by hand and V; it should be noted that; utilize the U phase in three phase mains to power mutually with W, and utilize the V phase in three phase mains to power mutually and all fall into protection scope of the present invention with W.With reference to above two kinds of situations, can be according to the feedback current detecting, detect the current interruption situation of feedback current and/or the fluctuation situation of feedback current, and judge whether phase shortage of three-phase electricity with this.

Hand arc welding machine three-phase electric power open phase checkout gear 31 of the present invention can comprise detecting unit, control module and power transformer, detecting unit connects this power transformer, power transformer be coupled respectively U phase and the V phase of three phase mains 32, detecting unit is for detection of feedback current, and control module judges whether phase shortage of three-phase electricity for the feedback current detecting according to detecting unit.

Power transformer is coupled in any two-phase in three phase mains by the present invention, can realize three-phase electric power open phase by the functional module such as power transformer and detecting unit, control module detects, without multiple step-down transformers and lack detection circuit are set, simplify circuit structure, cost-saving.

Fig. 3 a shows in the situation that power supply U, V, W three-phase are complete, arc welder in welding process, the waveform of the feedback current that hand arc welding machine three-phase electric power open phase checkout gear detects.From Fig. 3 a, can find out, hand arc welding machine is after arc process completes, and the feedback current waveform of output is steady, fluctuates less.

Fig. 3 b shows in the situation that power supply lacks W phase, hand arc welding machine is in welding process, one of waveform of the feedback current that three-phase electric power open phase checkout gear detects, from Fig. 3 b, can find out, feedback current in the time that the feedback current that lacks W phase time is complete with respect to three-phase is unstable, has obvious current interruption.

Fig. 3 c shows in the situation that power supply lacks W phase, in welding process, two of the waveform of the feedback current being detected by three-phase electric power open phase checkout gear, from Fig. 3 c, can find out, the fluctuation range that lacks the feedback current fluctuation range of the W phase time feedback current when complete with respect to three-phase is in a substantial change, and vibration frequency is higher.

In the control module of hand arc welding machine three-phase electric power open phase checkout gear 31 of the present invention, be provided with:

1, the first timer, the timing duration of the first timer equates with judging cycle t, the first counter can also record the time that feedback current peak value is corresponding.

2, judgement time counter, judge for recording executed in statistics duration T and the number of times of cycle t judges that the initial value of the value k of inferior counter is 1.

3, the first counter, the second counter and the 3rd counter, the first counter is for recording the number of times of feedback current current interruption, and the initial value of the value n1 of the first counter is 0; The second counter is for recording feedback current fluctuation frequently and the large number of times of fluctuation range, and the initial value of the value n2 of the second counter is 0; The 3rd counter fluctuates frequently and the large number of times of fluctuation range for the number of times and/or the feedback current that record feedback current current interruption, and the initial value of the value n3 of the 3rd counter is 0.

In the control module of hand arc welding machine three-phase electric power open phase checkout gear 31, be also provided with following parameter:

1, the sampling period, is used to indicate detecting unit and detects feedback current according to the sampling period, and preferred, the sampling period can be set to 50us.

2, statistics duration T, i.e. measurement period, is the statistics duration of a three-phase electric power open phase detection, preferred, statistics duration can be set to 500ms.

3, judge cycle t, judge in cycle t at 1, hand arc welding machine three-phase electric power open phase checkout gear can be to judge that cycle t, as unit, carries out three-phase electric power open phase judgement, preferred, $t=\frac{1}{5}T.$

4, the first frequency threshold value N1, for the numerical value as reach the foundation of three-phase electric power open phase according to the number of times judgement of the feedback current current interruption of the first counter records; The second frequency threshold value N2, for the numerical value as judge the foundation that reaches three-phase electric power open phase according to the feedback current fluctuation that judges the second counter records number of times frequent and that fluctuation range is large; Count for the third time threshold value N3, for as according to judge that the number of times of feedback current current interruption of the 3rd counter records and/or the number of times that feedback current fluctuation is frequent and fluctuation range is large judge the numerical value of the foundation that reaches three-phase electric power open phase.Wherein, N1, N2, N3 are that those skilled in the art test with regard to getable empirical value according to limited number of time, preferred, N1<N3<N2.

5, time threshold T1, for the foundation as reach three-phase electric power open phase according to the frequent judgement of feedback current fluctuation, preferred, T1=9-11ms.

6, judge frequency threshold value K, K=T/t.

7, two-dimensional array P, comprises multiple memory cell, and for recording, in 1 statistics duration T, each judges value n1, the value n2 of the second counter and the value n3 of the 3rd counter of the first counter in cycle t to each memory cell.

8, the first current threshold A1, for the current value of foundation as judging feedback current current interruption; The second current threshold A2, for the current value as judging the foundation that feedback current fluctuation is larger; Wherein, A1 and A2 are empirical value, can rule of thumb set A1>A2.

On hand arc welding machine, be provided with setting electric current, in order to limit the feedback current peak-to-peak value of hand arc welding machine, set electric current and can between 20A-400A, set.The peak-to-peak value of feedback current changes according to the difference of setting electric current, and A1 and A2 are that those skilled in the art test with regard to getable empirical value by limited number of time, and A1 is less than setting current value, and is greater than normal output current feedback peak-to-peak value.Below enumerate several conventional setting electric currents and corresponding feedback current peak-to-peak value, the first current threshold A1 and the second current threshold A2, specifically as shown in table 1:

Table 1

9, the first default duration, for as judge feedback current fluctuation frequently and the large judgement cycle of fluctuation range; The second default duration, for the judgement cycle as judging feedback current current interruption.

10, the 4th frequency threshold value N4, for reaching the numerical value of the foundation of three-phase electric power open phase as number of times judgement frequent according to feedback current fluctuation and that fluctuation range is large; The 5th frequency threshold value N5, for the numerical value as reach the foundation of three-phase electric power open phase according to the number of times judgement of feedback current current interruption.

11, period of waves, for the foundation as reach three-phase electric power open phase according to the frequent judgement of feedback current fluctuation, preferred, can be 9-11ms period of waves.

Embodiment mono-

Any two-phase in the power transformer coupling three phase mains of hand arc welding machine three-phase electric power open phase checkout gear.In hand arc welding machine three-phase electric power open phase checkout gear, be preset with: the first default duration, period of waves, the first current threshold and the 4th frequency threshold value; The described first default duration is greater than described period of waves.

The manual arc welder three-phase electricity detection method that the present embodiment provides comprises the steps:

Detect feedback current, and according to the feedback current detecting, judge whether phase shortage of three-phase electricity.

Concrete, in the first default duration, calculate the number of times that feedback current peak-to-peak value in continuous period of waves and described feedback current peak-to-peak value are greater than described the first current threshold, and described number of times is compared with described the 4th frequency threshold value, if described number of times is greater than described the 4th frequency threshold value, judge three-phase electric power open phase, and output alarm signal.

In the present embodiment, to carry out the flow process of three-phase electric power open phase detection as follows for hand arc welding machine three-phase electric power open phase checkout gear:

Detect feedback current, and the feedback current detecting according to detecting unit 42, in the first default duration, calculate the feedback current peak-to-peak value in period of waves.Conventionally, be 9-11ms period of waves, preferred, gets 10ms.

The feedback current peak-to-peak value calculating is compared with the first default current threshold A1, and record the number of times that the first default duration internal feedback current peak peak value is greater than the first current threshold A1.Wherein, the setting of the first current threshold A1, referring to table 1, does not repeat them here.

Preferably, the first default duration can be set as for 1 second.

Judge whether the number of times that the first default duration internal feedback current peak peak value is greater than the first current threshold A1 is greater than the 4th default frequency threshold value, if be greater than, hand arc welding machine phase shortage is described, and output alarm signal.Conventionally, if the number of times that 1 second internal feedback current peak peak value is greater than the first current threshold A1 exceedes (the 4th frequency threshold value can be set as 80 times) 80 times, think that feedback current fluctuation range is large and fluctuation is frequent, i.e. three-phase electric power open phase, reports to the police.

Preferably, the feedback current detecting can also for example, can also be shown by the waveform of display unit (oscillograph), observe intuitively the situation of change of feedback current for user.

To set electric current as 20A, the first current threshold is set to 18A, Second Threshold is set to 80 times, be 10ms period of waves, it is example that the first default duration is set to 1s, hand arc welding machine three-phase electric power open phase checkout gear detects feedback current in real time, calculate the peak-to-peak value of 10ms internal feedback electric current, by the peak-to-peak value calculating and 18A(the first current threshold) compare, record the default duration of 1s(first) interior peak-to-peak value is greater than the number of times of 18A, and judges whether this number of times is greater than 80(the 4th frequency threshold value), if be greater than, judge three-phase electric power open phase, report to the police.

In the embodiment of the present invention one, power transformer is coupled in to any two-phase in three phase mains, the number of times that is greater than the first current threshold by monitoring the first default duration internal feedback current peak peak value judges whether phase shortage of arc welder, without multiple step-down transformers and lack detection circuit are set, simplify circuit structure, improve stability, cost-saving.

Embodiment bis-

In embodiment bis-, any two-phase in the power transformer coupling three phase mains of hand arc welding machine three-phase electric power open phase checkout gear.In hand arc welding machine three-phase electric power open phase checkout gear, be provided with the second default duration and the 5th frequency threshold value, the feedback current detecting for basis, the number of times that the default duration internal feedback electric current of record second is zero, and the number of times that is zero at the second default duration internal feedback electric current is greater than the 5th frequency threshold value, be judged as three-phase electric power open phase, and output alarm signal.

Hardware configuration and the annexation of the hand arc welding machine three-phase electric power open phase checkout gear that embodiment bis-provides are similar to embodiment mono-, do not repeat them here, and embodiment bis-is from the difference of embodiment mono-: the implementation of carrying out three-phase electric power open phase detection is different.

Below in conjunction with Fig. 3 a and Fig. 3 c, the workflow of the hand arc welding machine three-phase electric power open phase checkout gear that the embodiment of the present invention two is provided elaborates.Fig. 3 c shows in the situation that power supply lacks W phase, arc welder in welding process, the waveform of the feedback current that three-phase electric power open phase checkout gear detects, as can be seen from the figure, feedback current in the time that the feedback current that lacks W phase time is complete with respect to three-phase is unstable, has obvious current interruption.

The flow process that described hand arc welding machine three-phase electric power open phase checkout gear carries out phase shortage detection is as follows:

Obtain the number of times that the second default duration internal feedback electric current is zero.Preferably, the second default duration can be set to 1 minute.

The number of times that is zero by the second default duration internal feedback electric current is compared with the 5th frequency threshold value, if the former is greater than the latter, three-phase electric power open phase is described, output alarm signal.Wherein, the setting of the 5th frequency threshold value is relevant with the speed of artificial spot welding, and conventionally, the number of times of artificial electric welding is 60-70 beat/min, and preferred, the 5th frequency threshold value can be set to 85 times.

For example, three-phase electric power open phase checkout gear detects feedback current in real time, the number of times (current interruption number of times) that to obtain 1 minute internal feedback electric current be zero, and judge in 1 minute, whether current interruption number of times is greater than 80 times, if be greater than, be judged as three-phase electric power open phase, and report to the police.

In the embodiment of the present invention two, power transformer is coupled in to any two-phase in three phase mains, judge whether phase shortage of arc welder by monitoring feedback current current interruption number of times in the second default duration, without multiple step-down transformers and lack detection circuit are set, simplify circuit structure, improve stability, cost-saving.

Embodiment tri-

In embodiment tri-, any two-phase in the power transformer coupling three phase mains of hand arc welding machine three-phase electric power open phase checkout gear.Hardware configuration and the annexation of the hand arc welding machine three-phase electric power open phase checkout gear that embodiment tri-provides are similar to embodiment mono-, two, do not repeat them here, embodiment tri-is with the difference of embodiment mono-, two: the hand arc welding machine three-phase electric power open phase checkout gear in embodiment tri-can either by detecting, feedback current fluctuation be frequent and fluctuation range is large, judge three-phase electric power open phase, again can be by detecting feedback current current interruption, judge three-phase electric power open phase, can also, by detecting above-mentioned two situations, judge three-phase electric power open phase.

Below take the feedback current oscillogram shown in Fig. 4 as example, and in conjunction with Fig. 5, the hand arc welding machine three-phase electric power open phase testing process that the embodiment of the present invention is provided is elaborated.As shown in Figure 5, hand arc welding machine three-phase electric power open phase testing process comprises the following steps:

Step 501, according to sampling period detection feedback current.

Concrete, the detecting unit of hand arc welding machine three-phase electric power open phase checkout gear detects feedback current according to the sampling period, and the feedback current detecting is sent to control module.

Step 502, according to the feedback current detecting, judges whether phase shortage of three-phase electricity.

Preferably, according to the feedback current detecting, detect the current interruption situation of feedback current and/or feedback current fluctuation situation, and judge whether phase shortage of three-phase electricity with this.

Concrete, the control module of hand arc welding machine three-phase electric power open phase checkout gear is judging in cycle t, according to the feedback current detecting, judge whether phase shortage of three-phase electricity, if cannot judge three-phase electric power open phase judging in cycle t, in the duration of (K-1) the individual judgement cycle t sum before current judgement cycle t and current judgement cycle t (1 statistics duration T), according to the feedback current detecting, judge whether phase shortage of three-phase electricity.

The operation below carry out in the process of three-phase electric power open phase detection and judgement, carrying out of hand arc welding machine three-phase electric power open phase checkout gear:

In the time that the control module of hand arc welding machine three-phase electric power open phase checkout gear receives the feedback current value of detecting unit transmission, the first timer starts timing, and in the time that timing duration t arrives, 1 judges that cycle t finishes, and needs to carry out following operation:

1, judgement time counter adds 1, i.e. k=k+1;

2, the value of n1, n2 in this judgement cycle t, n3 is kept in two-dimensional array P, that is, will judge cycle t _k-1in n1, n2, the value of n3 keep in two-dimensional array P[k-1] in the memory cell of [3].For example, if statistics duration T comprises that 5 judge cycle t, correspondingly, two-dimensional array P includes five groups of memory cell, the 1st judge that cycle t1 finishes after, the value of the n1 in t1 is stored in P[0] in [n1] (memory cell) (be P[0] [n1]=n1 ₀), the value of the n2 in t1 is stored in P[0] and in [n2] (be P[0] [n1]=n2 ₀), the value of the n3 in t1 is stored in P[0] and in [n3] (be P[0] [n3]=n3 ₀); The 2nd judge that cycle t2 finishes after, the value of the n1 in t2 is stored in P[1] in [n1] (be P[1] [n1]=n1 ₁), the value of the n2 in t2 is stored in P[1] and in [n2] (be P[1] [n2]=n2 ₁), the value of the n3 in t2 is stored in P[1] and in [n3] (be P[1] [n3]=n3 ₁); The 3rd judge that cycle t3 finishes after, the value of the n1 in t3 is stored in P[2] in [n1] (be P[2] [n1]=n1 ₂), the value of the n2 in t3 is stored in P[2] and in [n2] (be P[2] [n2]=n2 ₂), the value of the n3 in t3 is stored in P[2] and in [n3] (be P[2] [n3]=n3 ₂); The 4th judge that cycle t4 finishes after, the value of the n1 in t4 is stored in P[3] in [n1] (be P[3] [n1]=n1 ₃), the value of the n2 in t4 is stored in P[3] and in [n2] (be P[3] [n2]=n2 ₃), the value of the n3 in t4 is stored in P[3] and in [n3] (be P[3] [n3]=n3 ₃); The 5th judge that cycle t5 finishes after, the value of the n1 in t5 is stored in P[4] in [n1] (be P[4] [n1]=n1 ₄), the value of the n2 in t5 is stored in P[4] and in [n2] (be P[4] [n2]=n2 ₄), the value of the n3 in t5 is stored in P[4] and in [n3] (be P[4] [n3]=n3 ₄).

3, after the value of n1, n2 in this judgement cycle t, n3 is kept in to two-dimensional array P, by the first counter, the second counter and the 3rd counter O reset, reset to initial value 0 by n1, n2, n3.

Timing duration t at the first timer arrives (one judges that cycle t finishes) afterwards, in the time that the control module of hand arc welding machine three-phase electric power open phase checkout gear receives the feedback current value of detecting unit transmission again, the first timer restarts timing, to start another and judge the three-phase electric power open phase deterministic process of cycle t.

Below in conjunction with Fig. 6, to hand arc welding machine three-phase electric power open phase checkout gear according to the feedback current that detects, judge three-phase electricity whether the flow process of phase shortage be elaborated, this flow process comprises the following steps:

Step 601, in the time that the timing duration t of the first timer arrives, compares the value k of judgement time counter with judging frequency threshold value K, if k≤K performs step 602, otherwise, execution step 607.

Concrete, in the time that the timing duration t of the first timer arrives, the control module indication judgement time counter of hand arc welding machine three-phase electric power open phase checkout gear adds 1, be k=k+1, and the value k of judgement time counter is compared with judging frequency threshold value K, if k≤K, illustrates that the 1st the each judgement cycle t in statistics duration T not yet all completes three-phase electric power open phase judgement, performs step 602.If k>K, illustrate that the 1st all judgement cycle t in statistics duration T all complete three-phase electric power open phase judgement (the 1st time statistics finishes), or, all judgement cycle t in n statistics duration T all complete three-phase electric power open phase judgement (the n time statistics finishes), perform step 606.

Step 602-603, according to the feedback current value, the first current threshold A1, the second current threshold A2 that judge in cycle t, determine value n1, the value n2 of the second counter, the value n3 of the 3rd counter of the first counter, and according to n1, n2, n3, the first frequency threshold value N1, the second frequency threshold value N2 with count for the third time threshold value N3, judge whether phase shortage of three-phase electricity, if can judge three-phase electric power open phase, process ends, otherwise, execution step 604.

Concrete, if the control module of hand arc welding machine three-phase electric power open phase checkout gear is according to judging that feedback current value in cycle t can judge whether phase shortage of three-phase electricity, process ends, if according to the feedback current value judging in cycle t, cannot judge whether phase shortage of three-phase electricity, need further judgement, perform step 604.

The control module of hand arc welding machine three-phase electric power open phase checkout gear according to judge feedback current value in cycle t judge three-phase electricity whether the idiographic flow of phase shortage in subsequent step 701～713, be described in detail again.

Step 604, calculate the n2 sum m2 in (K-1) individual judgement cycle t before the n1 sum m1 in (K-1) individual judgement cycle t before n1 in current judgement cycle t and current judgement cycle t, n2 in current judgement cycle t and current judgement cycle t, and, the n3 sum m3 before the n3 in current judgement cycle t and current judgement cycle t in (K-1) individual judgement cycle t.

Concrete, the control module of hand arc welding machine three-phase electric power open phase checkout gear calculates respectively m1, m2, m3 according to the value of the n1 storing in each memory cell in two-dimensional array P, n2, n3.

$\mathrm{<figure-callout\; id="1"\; label="m"\; filenames="HDA0000477292480000041.png"\; state="\{\{state\}\}">m</figure-callout>}1=\underset{i=0}{\overset{K-1}{\mathrm{\&Sigma;}}}n{1}_i=\mathrm{<figure-callout\; id="1"\; label="n"\; filenames="HDA0000477292480000041.png"\; state="\{\{state\}\}">n</figure-callout>}{1}_0+\mathrm{<figure-callout\; id="1"\; label="n"\; filenames="HDA0000477292480000041.png"\; state="\{\{state\}\}">n</figure-callout>}{1}_1+\mathrm{<figure-callout\; id="1"\; label="n"\; filenames="HDA0000477292480000041.png"\; state="\{\{state\}\}">n</figure-callout>}{1}_2+......+n{1}_{K-1};$

$m2=\underset{i=0}{\overset{K-1}{\mathrm{\&Sigma;}}}n{2}_i=n{2}_0+n{2}_1+n{2}_2+......+n{2}_{K-1};$

$m3=\underset{i=0}{\overset{K-1}{\mathrm{\&Sigma;}}}n{3}_i=n{3}_0+n{3}_1+n{3}_2+......+n{3}_{K-1};$

Wherein, K is for judging frequency threshold value (K=T/t), is (i+1) number of times in the judgement cycle in this statistics duration.

M1 is i.e. 1 the statistics duration T of K judgement cycle t() in, the value n1's of each the first counter and; M2 is i.e. 1 the statistics duration T of K judgement cycle t() in, the value n2's of each the second counter and; M3 is i.e. 1 the statistics duration T of K judgement cycle t() in, the value n3's of each the 3rd counter and.

Step 605, according to m1 and N1, m2 and N2, m3 and N3 one of them, judge whether phase shortage of three-phase electricity, if can judge three-phase electric power open phase, process ends, if all cannot judge three-phase electric power open phase according to m1 and N1, m2 and N2, m3 and N3, carries out the judgement of next judgement cycle t.

Concrete, the control module of hand arc welding machine three-phase electric power open phase checkout gear is compared m1 respectively with N1, m2 is compared with N2, and m3 is compared with N3, if at least one establishment in m1 >=N1, m2 >=N2, m3 >=N3 judges three-phase electric power open phase; If m1<N1 and m2<N2 and m3<N3, explanation cannot be judged three-phase electric power open phase, carries out the judgement of next judgement cycle t, until while judging three-phase electric power open phase, process ends.Judge cycle t at the next one, still carry out according to step 601-step 607.

Step 606, n1, the n2 of (K-1) individual judgement cycle t before this judgement cycle t and n3 value are deleted from one group of memory cell of two-dimensional array P, and the value of other group memory cell (i.e. memory cell except deleting this group memory cell of n1, n2, n3 value) in two-dimensional array P is stored in last group of memory cell of this group memory cell successively, to replace the value of originally storing in described last group of memory cell.

Concrete, in the time of k>K, the control module of hand arc welding machine three-phase electric power open phase checkout gear is deleted n1, n2 and the n3 value of (K-1) individual judgement cycle t before this judgement cycle t from two-dimensional array P,, n1, n2 in the 1st group of memory cell of two-dimensional array P, n3 value are deleted.And n1, the n2 of other group memory cell of two-dimensional array P, the value of n3 are stored in last group of memory cell of this group memory cell successively, and replace in described last group of memory cell the value of original storage, by values 1 memory cell that moves to left of other group memory cell of two-dimensional array P, for example, P[0] [3]=P[1] [3], P[1] [3]=P[2] [3] ... by that analogy, last group memory cell P[4 of two-dimensional array P] [n1], P[4] [n2] and P[4] [n3] for storing n1, the n2 of next judgement cycle t, the value of n3.

Step 607, is set as k=k-1 by the value k of judgement time counter.

Concrete, the control module of hand arc welding machine three-phase electric power open phase checkout gear subtracts 1, i.e. k=k-1 by judgement time counter.

After step 607 is finished, continue execution step 601, to carry out the judgement of next judgement cycle t, re-execute step 601 and subsequent step, until while judging three-phase electric power open phase, just process ends.

As can be seen from Figure 4, in this embodiment, 1 judges that cycle t finishes also just to mean that 1 statistics duration T finishes, between twice adjacent statistics duration T, only differ 1 and judge cycle t, each statistics duration T comprises that 5 judge cycle t, between adjacent statistics duration T, it is partly overlapping relation, such as concerning the 2nd statistics duration T, it comprises that 5 judge cycle t, 1st～4 judge that cycle t is included in simultaneously and last time added up i.e. the 1st the statistics duration T of duration T() in, 2nd～5 judge that cycle t is included in i.e. the 3rd the statistics duration T of statistics duration T(thereafter simultaneously) in, 3rd～5 judge that cycle t is included in the 4th statistics duration T simultaneously, 4th～5 judge that cycle t is included in the 5th statistics duration T simultaneously, the 5th judges that cycle t is included in the 6th statistics duration T.Judge cycle t at interval of 1, just start statistics 1 time, each statistics is a statistics duration T, and each statistic processes is all carried out according to above-mentioned flow process, thereby realizes continuous recursion statistics, guarantees real-time and accuracy that three-phase electric power open phase detects.

It should be noted that, K the judgement cycle in each judgement cycle t(of initial first statistics duration T is first statistics duration T t) in, if according to n1, n2, n3, the first frequency threshold value N1, the second frequency threshold value N2 with count for the third time threshold value N3, cannot judge three-phase electric power open phase, owing to being first statistics duration T, before current judgement cycle t, not there is not (K-1) individual judgement cycle t, do not perform step 604, but directly perform step 601, continue the three-phase electric power open phase judgement of next judgement cycle t.

Judging in cycle t, judge whether phase shortage of three-phase electricity according to each feedback current value, specific implementation is as follows:

Determine the value n1 of the first counter according to feedback current value and the first current threshold A1, and judge whether phase shortage of three-phase electricity according to n1 and the first frequency threshold value N1, if can judge three-phase electric power open phase, process ends; If cannot judge three-phase electric power open phase according to n1 and N1, determine n3 according to the value n3 of n1 and the 3rd counter, and judge whether phase shortage of three-phase electricity according to the n3 determining and N3, if can judge three-phase electric power open phase, process ends; If cannot judge three-phase electric power open phase, the next feedback current peak value to be determined such as;

If cannot determine n1 according to feedback current value and the first current threshold A1, according to feedback current value, the second current threshold A2 and time threshold T1, determine the value n2 of the second counter, and judge whether phase shortage of three-phase electricity according to n2 and the second frequency threshold value N2, if can judge three-phase electric power open phase, process ends; If cannot judge three-phase electric power open phase according to n2 and N2, determine n3 according to n2 and n3, and judge whether phase shortage of three-phase electricity according to the n3 determining and N3, if can judge three-phase electric power open phase, process ends; If cannot judge three-phase electric power open phase, the next feedback current peak value to be determined such as.

In the manner described above, judging in cycle t, each feedback current value is carried out to three-phase electric power open phase judgement, if can judge three-phase electric power open phase, process ends; If cannot judge three-phase electric power open phase judging in cycle t, perform step 604.

Below in conjunction with Fig. 7, describe in detail according to each feedback current value and judge the whether idiographic flow of phase shortage of three-phase electricity.As shown in Figure 7, this flow process comprises the following steps:

Step 701, in current judgement cycle t, determines feedback current peak value according to the feedback current detecting, and calculates feedback current peak-to-peak value I according to feedback current peak value _peak-to-peak.

Concrete, the control module of hand arc welding machine three-phase electric power open phase checkout gear, according to the feedback current receiving, is determined the feedback current peak value in current judgement cycle t.Feedback current peak value is compared and is drawn according to multiple feedback current values, that is, current feedback current value is compared with previous feedback current value and a rear feedback current value respectively, when meeting the following conditions: I _anti-j>I _anti-j-1and I _anti-j>I _anti-j+1time, I is anti- _jbe feedback current peak value, wherein, j is the sequence number of feedback current value.Therefore, need to obtain at least 3 feedback current values and just may determine feedback current peak value.The mode of determining feedback current peak value belongs to prior art, does not repeat them here.

The control module of hand arc welding machine three-phase electric power open phase checkout gear calculates the poor of two adjacent feedback current peak values, and this difference is the feedback current peak-to-peak value I in current judgement cycle t _peak-to-peak.It should be noted that in embodiments of the present invention, feedback current peak value refers to the absolute value of current value, and feedback current peak-to-peak value is also the absolute value of the difference of feedback current peak value.

Because the sampling period is much smaller than judging cycle t, and as shown in Figure 4, feedback current is irregular cyclic swing, therefore, judges in cycle t and can obtain multiple feedback current peak values at 1, corresponding, also can obtain multiple feedback current peak-to-peak value I _peak-to-peak.

Step 702, by I _peak-to-peakcompare with the first current threshold A1, if I _peak-to-peak>=A1, performs step 703; If I _peak-to-peak<A1, performs step 707.

Concrete, the control module of hand arc welding machine three-phase electric power open phase checkout gear is by feedback current peak-to-peak value I _peak-to-peakcompare with the first current threshold A1, if I _peak-to-peak>=A1, illustrates that feedback current value excursion is larger, is the situation of feedback current current interruption, follow-up need to statistics by the number of times that feedback current current interruption is occurred, and judge on this basis whether phase shortage of three-phase electricity.If I _peak-to-peak<A1, illustrates that feedback current value changes, but does not belong to the situation of current interruption, needs follow-up combination the second current threshold A2, further judges whether phase shortage of three-phase electricity.

Step 703, makes n1=n1+1.

Concrete, if the control module of hand arc welding machine three-phase electric power open phase checkout gear is judged I _peak-to-peak>=A1, thinks that current interruption appears in feedback current, utilizes the number of times of the first counter records feedback current current interruption, therefore, makes the first counter add 1, i.e. n1=n1+1.

Step 704, compares n1 with the first frequency threshold value N1, if n1 >=N1 is judged as three-phase electric power open phase; If n1<N1, performs step 705.

Concrete, the control module of hand arc welding machine three-phase electric power open phase checkout gear is compared the n1 obtaining in step 703 with the first frequency threshold value N1, if n1 >=N1, illustrate judging in cycle t, feedback current occurs that the number of times of current interruption has met or exceeded N1, think judging that in cycle t, current interruption frequently occurs, thus, can be judged as three-phase electric power open phase.If n1<N1, illustrates judging in cycle t, occur that according to feedback current the number of times of current interruption still can not be judged three-phase electric power open phase, therefore, need further to judge according to the value n3 of the 3rd counter, perform step 705.

Step 705, makes n3=n1+n3.

Concrete, if the control module of hand arc welding machine three-phase electric power open phase checkout gear is judged n1<N1, calculate the value n3 sum of value n1 and the 3rd counter of the first counter, and value n3 using it as the 3rd counter.

Step 706, compares n3, if n3 >=N3 is judged as three-phase electric power open phase with counting for the third time threshold value N3; If n3<N3, the next feedback current peak value to be determined such as.

Concrete, the control module of hand arc welding machine three-phase electric power open phase checkout gear is compared the n3 calculating in step 705 with N3, if n3 >=N3, illustrate in this judgement cycle t, feedback current occurs the number of times of current interruption and/or feedback current fluctuation is frequent and the large number of times of fluctuation range has met or exceeded N3, thus, can be judged as three-phase electric power open phase.If n3<N3, illustrates that the three-phase electricity installation contact of power supply is unreal, or occur the situation that elementary coupling is disconnected, therefore, wait next feedback current peak value to be determined.

Step 707, by I _peak-to-peakcompare with the second current threshold A2, if I _peak-to-peak>=A2, performs step 708; If I _peak-to-peak<A2, the next feedback current peak value to be determined such as.

Concrete, if the control module of hand arc welding machine three-phase electric power open phase checkout gear is judged I _peak-to-peak<A1, by I _peak-to-peakcompare with the second current threshold A2, if I _peak-to-peak>=A2(is A2≤I now _peak-to-peak<A1), further judge I _peak-to-peakwhether meet the requirement of time threshold T1, perform step 708; If I _peak-to-peak<A2, illustrates I _peak-to-peakfluctuation range little, therefore, wait next feedback current peak-to-peak value to be determined.

Step 708, according to this I _peak-to-peakthe time of two corresponding feedback current peak values, calculate the time difference Δ t between these two feedback current peak values.

Concrete, the first counter can record described I _peak-to-peakthe time of two corresponding feedback current peak values, the control module of hand arc welding machine three-phase electric power open phase checkout gear is according to this feedback current peak-to-peak value I of the first counter records _peak-to-peakthe time of two corresponding feedback current peak values, the time of these two feedback current peak values is subtracted each other, obtain time difference Δ t.

Step 709, compares Δ t with time threshold T1, if Δ t<T1 performs step 710; If Δ t >=T1, the next feedback current peak value to be determined such as.

Concrete, the control module of hand arc welding machine three-phase electric power open phase checkout gear is compared the Δ t calculating with time threshold T1, if Δ t<T1 illustrates that feedback current fluctuation is frequent, perform step 710.If Δ t >=T1, although explanation feedback current fluctuation range is larger, fluctuates not frequent, therefore, wait next feedback current peak value to be determined.

Step 710, makes n2=n2+1.

Concrete, if the control module of hand arc welding machine three-phase electric power open phase checkout gear is judged A2≤I _peak-to-peak<A1, and Δ t<T1, think that feedback current fluctuation range is large and fluctuation is frequent, utilizes the second counter records feedback current fluctuation frequently and the large number of times of fluctuation range, therefore, makes the second counter add 1, i.e. n2=n2+1.

Step 711, compares n2 with the second frequency threshold value N2, if n2 >=N2 is judged as three-phase electric power open phase; If n2<N2, performs step 712.

Concrete, the control module of hand arc welding machine three-phase electric power open phase checkout gear is compared the n2 obtaining in step 710 with the second frequency threshold value N2, if n2 >=N2, illustrate judging in cycle t, feedback current fluctuates frequently and the large number of times of fluctuation range has met or exceeded N2, judging cycle t internal feedback electric current frequently and fluctuation, can be judged as three-phase electric power open phase.If n2<N2, illustrates judging in cycle t, feedback current fluctuation number of times frequent and that fluctuation range is large is many not enough, therefore, waits next feedback current peak value to be determined.

Step 712, makes n3=n2+n3.

Concrete, if the control module of hand arc welding machine three-phase electric power open phase checkout gear is judged n2<N2, calculate the value n3 sum of value n2 and the 3rd counter of the second counter, and value n3 using it as the 3rd counter.

Step 713, compares n3, if n3 >=N3 is judged as three-phase electric power open phase with counting for the third time threshold value N3; If n3<N3, the next feedback current peak value to be determined such as.

Concrete, the control module of hand arc welding machine three-phase electric power open phase checkout gear is compared the n3 calculating in step 712 with N3, if n3 >=N3, illustrate judging in cycle t, feedback current occurs the number of times of current interruption and/or feedback current fluctuation is frequent and the large number of times of fluctuation range has met or exceeded N3, can be judged as three-phase electric power open phase.If n3<N3, illustrates that the three-phase electricity installation contact of power supply is unreal, or occur the situation that elementary coupling is disconnected, therefore, wait next feedback current peak value to be determined.

Can find out by step 701-713, by this hand arc welding machine three-phase electric power open phase testing process, can be judging in cycle t, effectively judge for various phase shortage situations, for example, there is the situation of feedback current current interruption, can judge by the value n1 of the first counter; There is feedback current frequent fluctuation and the large situation of fluctuation range, can judge by the value n2 of the second counter, and there is current interruption in feedback current and/or occurs frequent fluctuation and situation that fluctuation range is large, can judge by the value n3 of the 3rd counter.

The control module of hand arc welding machine three-phase electric power open phase checkout gear, judging in cycle t, is determined feedback current peak value in real time according to the feedback current peak value receiving, and often determines a feedback current peak I _peak-to-peak, just judge according to above-mentioned steps 701-713, to determine whether phase shortage of three-phase electricity.

The embodiment of the present invention also provides a kind of hand arc welding machine three-phase electric power open phase checkout gear, and as shown in Figure 8, this device comprises:

Detecting unit 42, control module 43 and power transformer 41, the power transformer 41 any two-phase in three phase mains that is coupled, with thinking the power supply of hand arc welding machine three-phase electric power open phase checkout gear.

Detecting unit 42, connects power transformer 41, for detection of feedback current.

Control module 43, connects detecting unit 42, for judge whether phase shortage of three-phase electricity according to feedback current.

Preferably, in control module 43, be preset with: sampling period, the cycle of judgement t, statistics duration T and judge frequency threshold value K, K=T/t;

Detecting unit 42 specifically for, according to the default sampling period, detect feedback current.

Control module 43 specifically for, judging in cycle t, according to the feedback current detecting, judge whether phase shortage of three-phase electricity, if cannot judge three-phase electric power open phase judging in cycle t, before current judgement cycle t and current judgement cycle t in the duration of (K-1) individual judgement cycle t sum, according to the feedback current detecting, judge whether phase shortage of three-phase electricity.

Further, in control module 43, be also preset with: the first timer, the timing duration of the first counter is judgement cycle t; Judgement time counter, judge for recording executed in statistics duration T and the number of times of cycle t judges that the initial value of the value k of inferior counter is 1; The first counter, the second counter and the 3rd counter, the initial value of the value n1 of the first counter is that the initial value of the value n2 of 0, the second counter is that the initial value of the value n3 of 0, the three counter is 0; The first frequency threshold value N1, the second frequency threshold value N2 and for the third time several threshold value N3, N1<N3<N2; The first current threshold A1 and the second current threshold A2, A1>A2; And, time threshold T1;

In the time that detecting unit 42 detects feedback current value, the first timer starts timing; In the time that the timing duration t of the first timer arrives, judgement time counter is added to 1, and by the first counter, the second counter and the 3rd counter O reset, and in the time feedback current value again being detected, the first timer restarts timing;

Control module 43 specifically for, judge whether phase shortage of three-phase electricity according to following steps:

Step a, in the time that the timing duration t of the first timer arrives, compares the value k of judgement time counter, if k≤K performs step b with judging frequency threshold value K;

Step b, according to the feedback current value, the first current threshold A1, the second current threshold A2 that judge in cycle t, determine value n1, the value n2 of the second counter, the value n3 of the 3rd counter of the first counter, and according to n1, n2, n3, the first frequency threshold value N1, the second frequency threshold value N2 with count for the third time threshold value N3, judge whether phase shortage of three-phase electricity, if can judge three-phase electric power open phase, process ends, otherwise, execution step c;

Step c, calculate the n2 sum m2 in (K-1) individual judgement cycle t before the n1 sum m1 in (K-1) individual judgement cycle t before n1 in current judgement cycle t and current judgement cycle t, n2 in current judgement cycle t and current judgement cycle t, and, the n3 sum m3 before the n3 in current judgement cycle t and current judgement cycle t in (K-1) individual judgement cycle t;

Steps d, according to m1 and N1, m2 and N2, m3 and N3 one of them, judge whether phase shortage of three-phase electricity, if can judge three-phase electric power open phase, process ends; If all cannot judge three-phase electric power open phase according to m1 and N1, m2 and N2, m3 and N3, perform step a, until while judging three-phase electric power open phase, process ends.

Further, in control module 43, be also preset with the two-dimensional array P of the value of the n1, the n2 that judge cycle t for recording each in 1 statistic period T, n3;

Control module 43 also for, in the time that the timing duration t of the first timer arrives, before by the first counter, the second counter and the 3rd counter O reset, the value of n1, n2 in this judgement cycle t, n3 is kept in one group of memory cell of two-dimensional array P;

Control module 43 also for, in the time of k>K, judge whether phase shortage of three-phase electricity according to following steps:

Step e, n1, the n2 of (K-1) individual judgement cycle t before this judgement cycle t and the value of n3 are deleted from one group of memory cell of two-dimensional array P, and n1, the n2 of other group memory cell in two-dimensional array P, the value of n3 are stored in last group of memory cell of this group memory cell successively;

Step f, subtracts 1 by judgement time counter, and performs step a, until while judging three-phase electric power open phase, process ends.

Concrete, control module 43 specifically for, determine the value n1 of the first counter according to feedback current value and the first current threshold A1, and judge whether phase shortage of three-phase electricity according to n1 and the first frequency threshold value N1, if can judge three-phase electric power open phase, process ends; If cannot judge three-phase electric power open phase according to n1 and N1, determine n3 according to the value n3 of n1 and the 3rd counter, and judge whether phase shortage of three-phase electricity according to the n3 determining and N3, if can judge three-phase electric power open phase, process ends; If cannot judge three-phase electric power open phase, the next feedback current peak value to be determined such as; And, if cannot determine n1 according to feedback current value and A1, according to feedback current value, the second current threshold A2 and time threshold T1, determine the value n2 of the second counter, and judge whether phase shortage of three-phase electricity according to n2 and the second frequency threshold value N2, if can judge three-phase electric power open phase, process ends; If cannot judge three-phase electric power open phase according to n2 and N2, determine n3 according to n2 and n3, and judge whether phase shortage of three-phase electricity according to the n3 determining and N3, if can judge three-phase electric power open phase, process ends; If cannot judge three-phase electric power open phase, the next feedback current peak value to be determined such as; And, if according to judging that the each feedback current value in cycle t can judge three-phase electric power open phase, process ends, otherwise, execution step c.

Concrete, control module 43 specifically for, judge three-phase electric power open phase according to following steps:

Step h, in current judgement cycle t, determines feedback current peak value according to the feedback current detecting, and calculates feedback current peak-to-peak value I according to feedback current peak value _peak-to-peak;

Step I, by I _peak-to-peakcompare with the first current threshold A1, if I _peak-to-peak>=A1, performs step j;

Step j, n1=n1+1;

Step k, compares n1 with the first frequency threshold value N1, if n1 >=N1 is judged as three-phase electric power open phase; If n1<N1, performs step l;

Step l, n3=n1+n3;

Step m, compares n3, if n3 >=N3 is judged as three-phase electric power open phase, process ends with counting for the third time threshold value N3; If n3<N3, the next feedback current peak value to be determined such as.

Further, in control module 43, be also preset with time threshold T1;

Control module 43 also for, judge whether phase shortage of three-phase electricity according to following steps:

Work as I _peak-to-peakwhen <A1, carry out following steps:

Step n, by I _peak-to-peakcompare with the second current threshold A2, if I _peak-to-peak>=A2, performs step o; If I _peak-to-peak<A2, the next feedback current peak value to be determined such as;

Step o, according to described I _peak-to-peakthe time of two corresponding feedback current peak values, calculate the time difference Δ t between described two feedback current peak values;

Step p, compares Δ t with time threshold T1, if Δ t<T1 performs step q; If Δ t >=T1, the next feedback current peak value to be determined such as;

Step q, n2=n2+1;

Step r, compares n2 with the second frequency threshold value N2, if n2 >=N2 is judged as three-phase electric power open phase; If n2<N2, performs step s;

Step s, n3=n2+n3;

Step t, compares n3, if n3 >=N3 is judged as three-phase electric power open phase with counting for the third time threshold value N3; If n3<N3, the next feedback current peak value to be determined such as.

Further, described device also comprises alarm unit 44;

In control module 43, be preset with: the first default duration, period of waves, the first current threshold and the 4th frequency threshold value; The described first default duration is greater than described period of waves;

Control module 43 specifically for, in the first default duration, calculate the number of times that the peak-to-peak value of the feedback current in continuous period of waves and described peak-to-peak value are greater than described the first current threshold, and described number of times is compared with described the 4th frequency threshold value, in the time that described number of times is greater than described the 4th frequency threshold value, judge three-phase electric power open phase, and indication warning unit 44 output alarm signals.

Preferably, described device also comprises alarm unit 44;

In control module 43, be preset with: the second default duration and the 5th frequency threshold value;

Control module 43 specifically for, the number of times that the default duration internal feedback electric current of record second is zero, and by described number of times and described the 5th several three threshold, in the time that described number of times is greater than described the 5th frequency threshold value, judge three-phase electric power open phase, and indicate described alarm unit output alarm signal.

Preferably, detecting unit can be selected CT current transformer, for example, and L10PxxxD15; Control module can be selected hand arc welding machine control P plate, for example, CPU, IC(Integrated Circuit, surface-mounted integrated circuit) etc. element, also can select DSP(digital signal processor), for example, TMS320F28027.Alarm unit 44 can adopt existing sound, light crossing-signal.

Be understandable that, above embodiment is only used to principle of the present invention is described and the illustrative embodiments that adopts, but the present invention is not limited thereto.For those skilled in the art, without departing from the spirit and substance in the present invention, can make various modification and improvement, these modification and improvement are also considered as protection scope of the present invention.

Claims (18)

1. a hand arc welding machine three-phase electric power open phase detection method, it is characterized in that, be applied to the hand arc welding machine three-phase electric power open phase checkout gear that comprises power transformer, any two-phase in described power transformer coupling three phase mains, with thinking the power supply of hand arc welding machine three-phase electric power open phase checkout gear; Described method comprises:

Detect feedback current;

According to the feedback current detecting, judge whether phase shortage of three-phase electricity.

2. the method for claim 1, is characterized in that, in described hand arc welding machine three-phase electric power open phase checkout gear, is preset with: sampling period, the cycle of judgement t, statistics duration T and judge frequency threshold value K, K=T/t;

Described detection feedback current, specifically comprises: according to the default sampling period, detect feedback current;

According to the feedback current detecting, judge whether phase shortage of three-phase electricity, specifically comprise:

Judging in cycle t, according to the feedback current detecting, judge whether phase shortage of three-phase electricity, if cannot judge three-phase electric power open phase judging in cycle t, before current judgement cycle t and current judgement cycle t in the duration of (K-1) individual judgement cycle t sum, according to the feedback current detecting, judge whether phase shortage of three-phase electricity.

3. method as claimed in claim 2, is characterized in that, in described hand arc welding machine three-phase electric power open phase checkout gear, is also preset with:

The first timer, the timing duration of the first counter is judgement cycle t;

Judgement time counter, judge for recording executed in statistics duration T and the number of times of cycle t judges that the initial value of the value k of inferior counter is 1;

The first counter, the second counter and the 3rd counter, the initial value of the value n1 of the first counter is that the initial value of the value n2 of 0, the second counter is that the initial value of the value n3 of 0, the three counter is 0;

The first frequency threshold value N1, the second frequency threshold value N2 and for the third time several threshold value N3, N1<N3<N2;

The first current threshold A1 and the second current threshold A2, A1>A2;

Time threshold T1;

In the time feedback current value being detected, the first timer starts timing; In the time that the timing duration t of the first timer arrives, judgement time counter is added to 1, and by the first counter, the second counter and the 3rd counter O reset, and in the time feedback current value again being detected, the first timer restarts timing;

According to the feedback current detecting, judge whether phase shortage of three-phase electricity, specifically comprise the following steps:

Step a, in the time that the timing duration t of the first timer arrives, compares the value k of judgement time counter, if k≤K performs step b with judging frequency threshold value K;

Step b, according to the feedback current value, the first current threshold A1, the second current threshold A2 that judge in cycle t, determine value n1, the value n2 of the second counter, the value n3 of the 3rd counter of the first counter, and according to n1, n2, n3, the first frequency threshold value N1, the second frequency threshold value N2 with count for the third time threshold value N3, judge whether phase shortage of three-phase electricity, if can judge three-phase electric power open phase, process ends, otherwise, execution step c;

Step c, calculate the n2 sum m2 in (K-1) individual judgement cycle t before the n1 sum m1 in (K-1) individual judgement cycle t before n1 in current judgement cycle t and current judgement cycle t, n2 in current judgement cycle t and current judgement cycle t, and, the n3 sum m3 before the n3 in current judgement cycle t and current judgement cycle t in (K-1) individual judgement cycle t;

Steps d, according to m1 and N1, m2 and N2, m3 and N3 one of them, judge whether phase shortage of three-phase electricity, if can judge three-phase electric power open phase, process ends; If all cannot judge three-phase electric power open phase according to m1 and N1, m2 and N2, m3 and N3, perform step a, until while judging three-phase electric power open phase, process ends.

4. method as claimed in claim 3, is characterized in that, is also preset with the two-dimensional array P of the value of the n1, the n2 that judge cycle t for recording each in 1 statistic period T, n3 in described hand arc welding machine three-phase electric power open phase checkout gear;

In the time that the timing duration t of the first timer arrives, before by the first counter, the second counter and the 3rd counter O reset, also carry out following operation: the value of n1, n2 in this judgement cycle t, n3 is kept in one group of memory cell of two-dimensional array P;

If k>K, described method is further comprising the steps of:

Step e, n1, the n2 of (K-1) individual judgement cycle t before this judgement cycle t and the value of n3 are deleted from one group of memory cell of two-dimensional array P, and n1, the n2 of other group memory cell in two-dimensional array P, the value of n3 are stored in last group of memory cell of this group memory cell successively;

Step f, subtracts 1 by judgement time counter, and performs step a, until while judging three-phase electric power open phase, process ends.

5. the method as described in claim 3 or 4, is characterized in that, described step b is specially:

Determine the value n1 of the first counter according to feedback current value and the first current threshold A1, and judge whether phase shortage of three-phase electricity according to n1 and the first frequency threshold value N1, if can judge three-phase electric power open phase, process ends; If cannot judge three-phase electric power open phase according to n1 and N1, determine n3 according to the value n3 of n1 and the 3rd counter, and judge whether phase shortage of three-phase electricity according to the n3 determining and N3, if can judge three-phase electric power open phase, process ends; If cannot judge three-phase electric power open phase, the next feedback current peak value to be determined such as;

If cannot determine n1 according to feedback current value and A1,, according to feedback current value, the second current threshold A2 and time threshold T1, determine the value n2 of the second counter, and judge whether phase shortage of three-phase electricity according to n2 and the second frequency threshold value N2, if can judge three-phase electric power open phase, process ends; If cannot judge three-phase electric power open phase according to n2 and N2, determine n3 according to n2 and n3, and judge whether phase shortage of three-phase electricity according to the n3 determining and N3, if can judge three-phase electric power open phase, process ends; If cannot judge three-phase electric power open phase, the next feedback current peak value to be determined such as;

If according to judging that the each feedback current value in cycle t can judge three-phase electric power open phase, process ends, otherwise, execution step c.

6. method as claimed in claim 5, is characterized in that, determines the value n1 of the first counter according to feedback current value and the first current threshold A1, and judges whether phase shortage of three-phase electricity according to n1 and the first frequency threshold value N1, specifically comprises the following steps:

Step h, in current judgement cycle t, determines feedback current peak value according to the feedback current detecting, and calculates feedback current peak-to-peak value I according to feedback current peak value _peak-to-peak;

Step I, by I _peak-to-peakcompare with the first current threshold A1, if I _peak-to-peak>=A1, performs step j;

Step j, n1=n1+1;

Step k, compares n1 with the first frequency threshold value N1, if n1 >=N1 is judged as three-phase electric power open phase; If n1<N1, performs step l;

Step l, n3=n1+n3;

Step m, compares n3, if n3 >=N3 is judged as three-phase electric power open phase, process ends with counting for the third time threshold value N3; If n3<N3, the next feedback current peak value to be determined such as.

7. method as claimed in claim 6, is characterized in that, in described hand arc welding machine three-phase electric power open phase checkout gear, is also preset with time threshold T1;

If described according to judging that feedback current value and A1 in cycle t cannot determine n1, according to the feedback current value, the second current threshold A2 and the time threshold T1 that judge in cycle t, determine the value n2 of the second counter, and judge whether phase shortage of three-phase electricity according to n2 and the second frequency threshold value N2, be specially:

If I _peak-to-peak<A1, carries out following steps:

Step n, by I _peak-to-peakcompare with the second current threshold A2, if I _peak-to-peak>=A2, performs step o; If I _peak-to-peak<A2, the next feedback current peak value to be determined such as;

Step o, according to described I _peak-to-peakthe time of two corresponding feedback current peak values, calculate the time difference Δ t between described two feedback current peak values;

Step p, compares Δ t with time threshold T1, if Δ t<T1 performs step q; If Δ t >=T1, the next feedback current peak value to be determined such as;

Step q, n2=n2+1;

Step r, compares n2 with the second frequency threshold value N2, if n2 >=N2 is judged as three-phase electric power open phase; If n2<N2, performs step s;

Step s, n3=n2+n3;

Step t, compares n3, if n3 >=N3 is judged as three-phase electric power open phase with counting for the third time threshold value N3; If n3<N3, the next feedback current peak value to be determined such as.

8. the method for claim 1, is characterized in that, in described hand arc welding machine three-phase electric power open phase checkout gear, is preset with: the first default duration, period of waves, the first current threshold and the 4th frequency threshold value; The described first default duration is greater than described period of waves;

The feedback current that described basis detects, judges whether phase shortage of three-phase electricity, specifically comprises:

In the first default duration, calculate the number of times that the peak-to-peak value of the feedback current in continuous period of waves and described peak-to-peak value are greater than described the first current threshold, and described number of times is compared with described the 4th frequency threshold value, if described number of times is greater than described the 4th frequency threshold value, judge three-phase electric power open phase, and output alarm signal.

9. the method for claim 1, is characterized in that, in described hand arc welding machine three-phase electric power open phase checkout gear, is preset with: the second default duration and the 5th frequency threshold value;

The feedback current that described basis detects, judges whether phase shortage of three-phase electricity, specifically comprises:

The number of times that the default duration internal feedback electric current of record second is zero, and by described number of times and described the 5th several three threshold, if described number of times is greater than described the 5th frequency threshold value, judge three-phase electric power open phase, and output alarm signal.

10. a hand arc welding machine three-phase electric power open phase checkout gear, it is characterized in that, comprise: detecting unit, control module and power transformer, any two-phase in described power transformer coupling three phase mains, with thinking the power supply of hand arc welding machine three-phase electric power open phase checkout gear;

Described detecting unit, connects described power transformer, for detection of feedback current;

Described control module, connects described detecting unit, for judge whether phase shortage of three-phase electricity according to feedback current.

11. devices as claimed in claim 10, is characterized in that, in described control module, are preset with: sampling period, the cycle of judgement t, statistics duration T and judge frequency threshold value K, K=T/t;

Described detecting unit specifically for, according to the default sampling period, detect feedback current;

Described control module specifically for, judging in cycle t, according to the feedback current detecting, judge whether phase shortage of three-phase electricity, if cannot judge three-phase electric power open phase judging in cycle t, before current judgement cycle t and current judgement cycle t in the duration of (K-1) individual judgement cycle t sum, according to the feedback current detecting, judge whether phase shortage of three-phase electricity.

12. devices as claimed in claim 11, is characterized in that, in described control module, are also preset with: the first timer, and the timing duration of the first counter is judgement cycle t; Judgement time counter, judge for recording executed in statistics duration T and the number of times of cycle t judges that the initial value of the value k of inferior counter is 1; The first counter, the second counter and the 3rd counter, the initial value of the value n1 of the first counter is that the initial value of the value n2 of 0, the second counter is that the initial value of the value n3 of 0, the three counter is 0; The first frequency threshold value N1, the second frequency threshold value N2 and for the third time several threshold value N3, N1<N3<N2; The first current threshold A1 and the second current threshold A2, A1>A2; And, time threshold T1;

In the time that described detecting unit detects feedback current value, the first timer starts timing; In the time that the timing duration t of the first timer arrives, judgement time counter is added to 1, and by the first counter, the second counter and the 3rd counter O reset, and in the time feedback current value again being detected, the first timer restarts timing;

Described control module specifically for, judge whether phase shortage of three-phase electricity according to following steps:

Step a, in the time that the timing duration t of the first timer arrives, compares the value k of judgement time counter, if k≤K performs step b with judging frequency threshold value K;

Step b, according to the feedback current value, the first current threshold A1, the second current threshold A2 that judge in cycle t, determine value n1, the value n2 of the second counter, the value n3 of the 3rd counter of the first counter, and according to n1, n2, n3, the first frequency threshold value N1, the second frequency threshold value N2 with count for the third time threshold value N3, judge whether phase shortage of three-phase electricity, if can judge three-phase electric power open phase, process ends, otherwise, execution step c;

Step c, calculate the n2 sum m2 in (K-1) individual judgement cycle t before the n1 sum m1 in (K-1) individual judgement cycle t before n1 in current judgement cycle t and current judgement cycle t, n2 in current judgement cycle t and current judgement cycle t, and, the n3 sum m3 before the n3 in current judgement cycle t and current judgement cycle t in (K-1) individual judgement cycle t;

Steps d, according to m1 and N1, m2 and N2, m3 and N3 one of them, judge whether phase shortage of three-phase electricity, if can judge three-phase electric power open phase, process ends; If all cannot judge three-phase electric power open phase according to m1 and N1, m2 and N2, m3 and N3, perform step a, until while judging three-phase electric power open phase, process ends.

13. devices as claimed in claim 12, is characterized in that, are also preset with the two-dimensional array P of the value of the n1, the n2 that judge cycle t for recording each in 1 statistic period T, n3 in described control module;

Described control module also for, in the time that the timing duration t of the first timer arrives, before by the first counter, the second counter and the 3rd counter O reset, the value of n1, n2 in this judgement cycle t, n3 is kept in one group of memory cell of two-dimensional array P;

Described control module also for, in the time of k>K, judge whether phase shortage of three-phase electricity according to following steps:

Step e, n1, the n2 of (K-1) individual judgement cycle t before this judgement cycle t and the value of n3 are deleted from one group of memory cell of two-dimensional array P, and n1, the n2 of other group memory cell in two-dimensional array P, the value of n3 are stored in last group of memory cell of this group memory cell successively;

Step f, subtracts 1 by judgement time counter, and performs step a, until while judging three-phase electric power open phase, process ends.

14. devices as described in claim 12 or 13, it is characterized in that, described control module specifically for, determine the value n1 of the first counter according to feedback current value and the first current threshold A1, and judge whether phase shortage of three-phase electricity according to n1 and the first frequency threshold value N1, if can judge three-phase electric power open phase, process ends; If cannot judge three-phase electric power open phase according to n1 and N1, determine n3 according to the value n3 of n1 and the 3rd counter, and judge whether phase shortage of three-phase electricity according to the n3 determining and N3, if can judge three-phase electric power open phase, process ends; If cannot judge three-phase electric power open phase, the next feedback current peak value to be determined such as; And, if cannot determine n1 according to feedback current value and A1, according to feedback current value, the second current threshold A2 and time threshold T1, determine the value n2 of the second counter, and judge whether phase shortage of three-phase electricity according to n2 and the second frequency threshold value N2, if can judge three-phase electric power open phase, process ends; If cannot judge three-phase electric power open phase according to n2 and N2, determine n3 according to n2 and n3, and judge whether phase shortage of three-phase electricity according to the n3 determining and N3, if can judge three-phase electric power open phase, process ends; If cannot judge three-phase electric power open phase, the next feedback current peak value to be determined such as; And, if according to judging that the each feedback current value in cycle t can judge three-phase electric power open phase, process ends, otherwise, execution step c.

15. device as claimed in claim 14, is characterized in that, described control module specifically for, judge three-phase electric power open phase according to following steps:

Step h, in current judgement cycle t, determines feedback current peak value according to the feedback current detecting, and calculates feedback current peak-to-peak value I according to feedback current peak value _peak-to-peak;

Step I, by I _peak-to-peakcompare with the first current threshold A1, if I _peak-to-peak>=A1, performs step j;

Step j, n1=n1+1;

Step k, compares n1 with the first frequency threshold value N1, if n1 >=N1 is judged as three-phase electric power open phase; If n1<N1, performs step l;

Step l, n3=n1+n3;

Step m, compares n3, if n3 >=N3 is judged as three-phase electric power open phase, process ends with counting for the third time threshold value N3; If n3<N3, the next feedback current peak value to be determined such as.

16. devices as claimed in claim 15, is characterized in that, are also preset with time threshold T1 in described control module;

Described control module also for, judge whether phase shortage of three-phase electricity according to following steps:

Work as I _peak-to-peakwhen <A1, carry out following steps:

Step n, by I _peak-to-peakcompare with the second current threshold A2, if I _peak-to-peak>=A2, performs step o; If I _peak-to-peak<A2, the next feedback current peak value to be determined such as;

Step o, according to described I _peak-to-peakthe time of two corresponding feedback current peak values, calculate the time difference Δ t between described two feedback current peak values;

Step p, compares Δ t with time threshold T1, if Δ t<T1 performs step q; If Δ t >=T1, the next feedback current peak value to be determined such as;

Step q, n2=n2+1;

Step r, compares n2 with the second frequency threshold value N2, if n2 >=N2 is judged as three-phase electric power open phase; If n2<N2, performs step s;

Step s, n3=n2+n3;

Step t, compares n3, if n3 >=N3 is judged as three-phase electric power open phase with counting for the third time threshold value N3; If n3<N3, the next feedback current peak value to be determined such as.

17. devices as claimed in claim 10, is characterized in that, described device also comprises alarm unit;

In described control module, be preset with: the first default duration, period of waves, the first current threshold and the 4th frequency threshold value; The described first default duration is greater than described period of waves;

Described control module specifically for, in the first default duration, calculate the number of times that the peak-to-peak value of the feedback current in continuous period of waves and described peak-to-peak value are greater than described the first current threshold, and described number of times is compared with described the 4th frequency threshold value, in the time that described number of times is greater than described the 4th frequency threshold value, judge three-phase electric power open phase, and indicate described alarm unit output alarm signal.

18. devices as claimed in claim 10, is characterized in that, described device also comprises alarm unit;

In described control module, be preset with: the second default duration and the 5th frequency threshold value;

Described control module specifically for, the number of times that the default duration internal feedback electric current of record second is zero, and by described number of times and described the 5th several three threshold, in the time that described number of times is greater than described the 5th frequency threshold value, judge three-phase electric power open phase, and indicate described alarm unit output alarm signal.

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