CN201732137U - Open-phase fault detection circuit for three-phase motors - Google Patents
Open-phase fault detection circuit for three-phase motors Download PDFInfo
- Publication number
- CN201732137U CN201732137U CN2010202977653U CN201020297765U CN201732137U CN 201732137 U CN201732137 U CN 201732137U CN 2010202977653 U CN2010202977653 U CN 2010202977653U CN 201020297765 U CN201020297765 U CN 201020297765U CN 201732137 U CN201732137 U CN 201732137U
- Authority
- CN
- China
- Prior art keywords
- phase
- amplifier
- unit
- current
- detecting unit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Landscapes
- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
Abstract
The utility model relates to an open-phase fault detection circuit for three-phase motors, which comprises a current phase detection unit, a wave form conversion unit, a monostable unit, a pulse period detection unit and an open-phase signal detection unit. The current phase detection unit is used for detecting three-phase current relative phase relationship, the wave form conversion unit is connected to the rear of the current phase detection unit and used for obtaining a rectangular pulse signal with the same frequency as the three-phase current relative phase relationship, the monostable unit is connected to the rear of the wave form conversion unit and used for generating a pulse signal with fixed pulse width and having the same frequency as the rectangular pulse signal, the pulse period detection unit is connected to the rear of the monostable unit and used for detecting the period of the pulse signal with the fixed pulse width, and the open-phase signal detection unit is connected to the rear of the pulse period detection unit and used for outputting an open-phase signal when detecting pulse signals larger than 1/3T. The current phase detection unit outputs the three-phase current relative phase relationship, the pulse signal larger than 120 degrees is detected via the open-phase signal detection unit finally via wave form conversion, and then the open-phase signal is outputted.
Description
Technical field
The utility model relates to a kind of threephase motor open phase fault testing circuit.
Background technology
In daily use, motor overheating or burn out, great majority are because due to the motor phase failure or the phase shortage, the motor phase failure generally has two kinds of situations: the star connection phase failure and the delta connection phase failure.The star connection phase failure is meant that when the winding of motor was star connection, power supply one line or winding one disconnected mutually, and then other two-phase windings in series are connected to electrical network, and motor shows as single-phase operation; The phase failure and the outer phase failure in the delta connection phase failure can be divided into again, i.e. the motor interior phase failure and control box are to the phase failure between the motor wiring end.Under the normal conditions, the phase differential of the triple-phase line electric current of three phase symmetry load is 120 °; During the phase failure outward of the star connection phase failure and delta connection, the line current of the phase failure is zero, and two line current phase differential are 180 ° in addition; And in the delta connection during phase failure, this phase current is zero, with this mutually between continuous two line currents of two terminals phase differential be 60 °, and the phase differential of the electric current of they and another line is 150 °.Existing threephase motor open phase fault detects the method whether the detection electric current that adopts exists, only is applicable to the situation of the outer phase failure of star connection and delta connection, but can't detect the interior phase failure of delta connection.
Summary of the invention
In view of this, the purpose of this utility model is to provide a kind of and realizes the threephase motor open phase fault testing circuit that the whole network phase failure detects by the relative phase relation of differentiating three-phase current.
For achieving the above object, the utility model adopts a kind of like this threephase motor open phase fault testing circuit, comprises
---the current phase detecting unit is used for detecting the relative phase relation of three-phase current;
---the waveform transformation unit, it is connected after the current phase detecting unit, is used for obtaining concerning with the three-phase current relative phase rectangular pulse signal of same frequency;
---the monostable unit, it is connected after the waveform transformation unit, be used for producing one with the pulse signal of the fixed pulse width of described rectangular pulse signal same frequency;
---the recurrence interval detecting unit, it is connected after the monostable unit, is used for detecting the cycle of the pulse signal of described fixed pulse width;
---phase failure signal detects the unit, and it is connected after the recurrence interval detecting unit, when the pulse signal that detects greater than 1/3T, and output phase failure signal.
Especially, described current phase detecting unit is a three-plase half wave rectifier circuit.
Especially, described monostable unit comprises the first amplifier U1A, the in-phase input end of the described first amplifier U1A is connected to first threshold voltage, the output terminal of described waveform transformation unit is connected to the inverting input of the described first amplifier U1A through a capacitor C 1, and the inverting input of the described first amplifier U1A also is connected to a direct current power positive end through a resistance R 7.
Especially, described recurrence interval detecting unit comprises the second amplifier U1C, the in-phase input end of the described second amplifier U1C is connected to second threshold voltage, the output terminal of described monostable unit is through a resistance R 10 and be connected to the inverting input of the described second amplifier U1C after meeting diode D5, and second inverting input of the described second amplifier U1C also is connected to ground through a capacitor C 2.
Especially, described phase failure signal detects the unit and comprises the 3rd amplifier U1D, the inverting input of described the 3rd amplifier U1D is connected to the 3rd threshold voltage, the output terminal of described recurrence interval detecting unit is connected to the in-phase input end of described the 3rd amplifier U1D through capacitor C 3, diode D7, the in-phase input end of described the 3rd amplifier U1D also is connected to ground through a capacitor C 4, described capacitor C 4 two ends also connect a resistance R 13, and are anti-and meet a diode D6 between the output terminal of described capacitor C 3 and ground.
The difference of the utility model and prior art is: the relative phase relation that adopts current phase detecting unit output three-phase current, waveform transformation through waveform transformation unit, monostable unit and recurrence interval detecting unit, finally detect the unit and detect pulse signal greater than 120 °, output phase failure signal by phase failure signal.Detecting the purpose that the unit is provided with capacitor C 3, capacitor C 4, diode D6, diode D7 and resistance R 13 at phase failure signal is, the output waveform of paired pulses cycle detection unit is carried out voltage multiplying rectifier, make the unexpected waveform that increases of recurrence interval, be the three-phase current phase differential greater than 120 ° waveform, electric capacity charged to be higher than the 3rd threshold voltage, thereby detect phase failure signal.
Description of drawings
Fig. 1 is the schematic diagram of threephase motor open phase fault testing circuit of the present utility model.
Embodiment
As shown in Figure 1, a kind of threephase motor open phase fault testing circuit comprises
---the current phase detecting unit is used for detecting the relative phase relation of three-phase current;
---the waveform transformation unit, it is connected after the current phase detecting unit, is used for obtaining concerning with the three-phase current relative phase rectangular pulse signal of same frequency;
---the monostable unit, it is connected after the waveform transformation unit, be used for producing one with the pulse signal of the fixed pulse width of described rectangular pulse signal same frequency;
One recurrence interval detecting unit, it is connected after the monostable unit, is used for detecting the cycle of the pulse signal of described fixed pulse width;
---phase failure signal detects the unit, and it is connected after the recurrence interval detecting unit, when the pulse signal that detects greater than 1/3T, and output phase failure signal.
The current phase detecting unit is a three-plase half wave rectifier circuit.The monostable unit comprises the first amplifier U1A, the in-phase input end of the first amplifier U1A is connected to first threshold voltage, the output terminal of waveform transformation unit is connected to the inverting input of the first amplifier U1A through a capacitor C 1, and the inverting input of the first amplifier U1A also is connected to a direct current power positive end through a resistance R 7.The recurrence interval detecting unit comprises the second amplifier U1C, the in-phase input end of the second amplifier U1C is connected to second threshold voltage, the output terminal of monostable unit is through a resistance R 10 and be connected to the inverting input of the second amplifier U1C after meeting diode D5, and second inverting input of the second amplifier U1C also is connected to ground through capacitor C 2.Phase failure signal detects the unit and comprises the 3rd amplifier U1D, the inverting input of the 3rd amplifier U1D is connected to the 3rd threshold voltage, the output terminal of recurrence interval detecting unit is connected to the in-phase input end of the 3rd amplifier U1D through capacitor C 3, diode D7, the in-phase input end of the 3rd amplifier U1D also is connected to ground through a capacitor C 4, capacitor C 4 two ends also connect a resistance R 13, and are anti-and meet a diode D6 between the output terminal of capacitor C 3 and ground.
The principle of work of this utility model circuit: by the relative phase relation of three phase half wave rectification current circuit output three-phase current, hysteresis comparator U1B in the waveform transformation unit 2, with three-phase current relative phase relation transformation is the rectangular pulse signal of same frequency, motor moves under the normal situation, A, B, C phase rectangular pulse signal are by phase sequence interval 1/3T successively, promptly 120 °, the signature waveform of formation one reflection three-phase current phase relation.The monostable unit, this signature waveform is pressed same frequency, after different duty is carried out conversion, detect the recurrent pulse waveform of this signature waveform by the recurrence interval detecting unit, last, capacitor C 3, capacitor C 4, diode D6, diode D7 and 13 pairs of these recurrent pulse waveforms of resistance R of adopting phase failure signal to detect in the unit carry out voltage multiplying rectifier, as the institute expectedly, when pulses low, capacitor C4 voltage can reduce, when pulse high level, be charged to the pulse amplitude of twice more then.When threephase motor is working properly, recurrence interval is 1/3T, the voltage of the in-phase input end of the 3rd amplifier U1D is low than the 3rd threshold voltage, the output terminal of the 3rd amplifier U1D is a low level, and the waveform that increases suddenly when the recurrence interval, promptly the three-phase current phase differential is greater than 120 ° waveform, detect voltage-doubler rectifier in the unit through phase failure signal after, the in-phase input end voltage of the 3rd amplifier U1D is higher than the 3rd threshold voltage, output phase failure signal.
Claims (6)
1. a threephase motor open phase fault testing circuit comprises
---the current phase detecting unit is used for detecting the relative phase relation of three-phase current;
---the waveform transformation unit, it is connected after the current phase detecting unit, is used for obtaining concerning with the three-phase current relative phase rectangular pulse signal of same frequency;
---the monostable unit, it is connected after the waveform transformation unit, be used for producing one with the pulse signal of the fixed pulse width of described rectangular pulse signal same frequency;
---the recurrence interval detecting unit, it is connected after the monostable unit, is used for detecting the cycle of the pulse signal of described fixed pulse width;
---phase failure signal detects the unit, and it is connected after the recurrence interval detecting unit, when the pulse signal that detects greater than 1/3T, and output phase failure signal.
2. a kind of threephase motor open phase fault testing circuit according to claim 1, it is characterized in that: described current phase detecting unit is a three-plase half wave rectifier circuit.
3. a kind of threephase motor open phase fault testing circuit according to claim 1 and 2, it is characterized in that: described monostable unit comprises first amplifier (U1A), the in-phase input end of described first amplifier (U1A) is connected to first threshold voltage, the output terminal of described waveform transformation unit is connected to the inverting input of described first amplifier (U1A) through an electric capacity (C1), and the inverting input of described first amplifier (U1A) also is connected to a direct current power positive end through a resistance (R7).
4. a kind of threephase motor open phase fault testing circuit according to claim 1 and 2, it is characterized in that: described recurrence interval detecting unit comprises second amplifier (U1C), the in-phase input end of described second amplifier (U1C) is connected to second threshold voltage, the output terminal of described monostable unit is through a resistance (R10) and be connected to the inverting input of described second amplifier (U1C) after connecing diode (D5), and second inverting input of described second amplifier (U1C) also is connected to ground through an electric capacity (C2).
5. a kind of threephase motor open phase fault testing circuit according to claim 3, it is characterized in that: described recurrence interval detecting unit comprises second amplifier (U1C), the in-phase input end of described second amplifier (U1C) is connected to second threshold voltage, the output terminal of described monostable unit is through a resistance (R10) and be connected to the inverting input of described second amplifier (U1C) after connecing diode (D5), and second inverting input of described second amplifier (U1C) also is connected to ground through an electric capacity (C2).
6. a kind of threephase motor open phase fault testing circuit according to claim 1 and 2, it is characterized in that: described phase failure signal detects the unit and comprises the 3rd amplifier (U1D), the inverting input of described the 3rd amplifier (U1D) is connected to the 3rd threshold voltage, the output terminal of described recurrence interval detecting unit is through electric capacity (C3), diode (D7) is connected to the in-phase input end of described the 3rd amplifier (U1D), the in-phase input end of described the 3rd amplifier (U1D) also is connected to ground through an electric capacity (C4), described electric capacity (C4) two ends also connect a resistance (R13), and are anti-and connect a diode (D6) between the output terminal of described electric capacity (C3) and ground.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010202977653U CN201732137U (en) | 2010-08-16 | 2010-08-16 | Open-phase fault detection circuit for three-phase motors |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010202977653U CN201732137U (en) | 2010-08-16 | 2010-08-16 | Open-phase fault detection circuit for three-phase motors |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN201732137U true CN201732137U (en) | 2011-02-02 |
Family
ID=43523296
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2010202977653U Expired - Fee Related CN201732137U (en) | 2010-08-16 | 2010-08-16 | Open-phase fault detection circuit for three-phase motors |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN201732137U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101937041A (en) * | 2010-08-16 | 2011-01-05 | 欣灵电气股份有限公司 | Open phase fault detecting circuit for three-phase motor |
| CN103823181A (en) * | 2012-11-19 | 2014-05-28 | 珠海格力电器股份有限公司 | Motor assembling unit quality detection system and method |
-
2010
- 2010-08-16 CN CN2010202977653U patent/CN201732137U/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101937041A (en) * | 2010-08-16 | 2011-01-05 | 欣灵电气股份有限公司 | Open phase fault detecting circuit for three-phase motor |
| CN103823181A (en) * | 2012-11-19 | 2014-05-28 | 珠海格力电器股份有限公司 | Motor assembling unit quality detection system and method |
| CN103823181B (en) * | 2012-11-19 | 2016-06-01 | 珠海格力电器股份有限公司 | A kind of motor unit quality detecting system and method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103219877B (en) | A kind of capacitor discharging circuit and changer | |
| CN103328987B (en) | Polarity detection circuit | |
| CN103399215B (en) | Phase-lack and low-voltage detection circuit for three-phase alternating current | |
| CN101799520B (en) | Open-phase detection method and detection circuit for three-phase power source | |
| CN104730433B (en) | The improved noise transmission vulnerability to jamming of more string arc fault detection devices | |
| CN104034981A (en) | Self-circulation aging test system and test method for frequency converter | |
| CN101614795B (en) | Default-phase signal detection circuit for three-phase power | |
| CN203178354U (en) | Three-phase AC electronic quantities detection circuit suitable for one-chip microcomputer | |
| CN202111456U (en) | Open-phase detection protection circuit | |
| CN203811727U (en) | Device for detecting commercial power | |
| CN102904429B (en) | The soft-start method of busbar voltage of alternating-current servo actuator and device | |
| CN201732137U (en) | Open-phase fault detection circuit for three-phase motors | |
| CN202710671U (en) | Open phase detecting circuit of three-phase power supply | |
| CN108206670A (en) | For detecting the monitoring system and monitoring method of photovoltaic battery pack string state of insulation | |
| CN101937041A (en) | Open phase fault detecting circuit for three-phase motor | |
| CN202721656U (en) | After current phase demodulation circuit | |
| CN203287421U (en) | Measurement circuit for three-phase AC voltage and current | |
| CN208350969U (en) | A kind of detection circuit and frequency converter | |
| CN102830266A (en) | Phase discriminating circuit of residual current phase | |
| CN103647442B (en) | A kind of precharge loop and electricity generation system | |
| CN102426282B (en) | Brushless direct current motor system and torque current detection circuit thereof | |
| CN201955399U (en) | Three-phase-current phase-lacking detection circuit | |
| CN205374613U (en) | Unbalanced three phase detection circuitry | |
| CN204179952U (en) | There is the low-voltage and high-current variable frequency power supply of real-time leakage current test function | |
| CN103595268B (en) | Frequency converter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20110202 Termination date: 20170816 |