CN110932230B - Temperature protection circuit for magnetic suspension frequency converter and magnetic suspension frequency converter - Google Patents
Temperature protection circuit for magnetic suspension frequency converter and magnetic suspension frequency converter Download PDFInfo
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- CN110932230B CN110932230B CN201911093359.7A CN201911093359A CN110932230B CN 110932230 B CN110932230 B CN 110932230B CN 201911093359 A CN201911093359 A CN 201911093359A CN 110932230 B CN110932230 B CN 110932230B
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H5/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal non-electric working conditions with or without subsequent reconnection
- H02H5/04—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal non-electric working conditions with or without subsequent reconnection responsive to abnormal temperature
- H02H5/047—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal non-electric working conditions with or without subsequent reconnection responsive to abnormal temperature using a temperature responsive switch
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
- H02H7/10—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers
- H02H7/12—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers for static converters or rectifiers
- H02H7/1216—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers for static converters or rectifiers for AC-AC converters
Abstract
The utility model provides a temperature protection circuit and magnetic suspension converter for magnetic suspension converter, relate to magnetic suspension converter technical field, this a temperature protection circuit for magnetic suspension converter includes temperature control module, first switch, under-voltage control module, second switch, temperature control module is connected with the power module electricity, first switch sets up in the route of power module and secondary survey module, under-voltage control module is connected with secondary survey module electricity, the second switch sets up in the route of power module and rectification contravariant power module. According to the invention, the temperature control module is used for controlling the first switch to be switched on or switched off, the secondary detection module is in a power-off or power-on state due to the switching on or off of the first switch, and the under-voltage control module is used for controlling the second switch to be switched on or switched off based on the power-off or power-on state of the secondary detection module, so that the electronic components in the frequency converter cabinet are prevented from being damaged due to overhigh temperature.
Description
Technical Field
The invention relates to the technical field of magnetic suspension frequency converters, in particular to a temperature protection circuit for a magnetic suspension frequency converter and the magnetic suspension frequency converter.
Background
The magnetic suspension frequency conversion centrifugal water chilling unit is a central air conditioner with low noise, small starting current, energy saving and high efficiency in the current market, and the magnetic suspension frequency converter is used for driving and controlling a compressor, is an important core component of the whole unit, and is a power electronic control device for controlling an alternating current motor by applying a frequency conversion technology and an electronic technology and changing the working power supply frequency of the motor. The magnetic suspension frequency converter mainly comprises a rectifying unit, a filtering unit, an inverting unit, a secondary testing module, a braking unit, a driving unit, a detecting unit, a micro-processing unit and the like, wherein each component part comprises a plurality of electronic components together, so that the internal structure of the magnetic suspension frequency converter also relates to a plurality of electronic components, and in order to ensure the normal work of the frequency converter and prevent the occurrence of some safety accidents, a protective measure is carried out on the electronic components inside the frequency converter, which is necessary.
In the current market, the working environment of the magnetic suspension frequency converter is generally required to be controlled below 40 ℃, and the internal temperature of the magnetic suspension frequency converter cannot exceed 55 ℃.
Because when the converter normally operates, the reactor in the converter cabinet can have heavy current to pass through, also can have a large amount of thermal production simultaneously, and the produced heat of other electrical parts in addition, so the inside temperature of converter also can rise. If the temperature exceeds the temperature which can be borne by the electric device, the components can be burnt out, open fire can be caused, and serious potential safety hazards are caused to the personal safety. Therefore, in order to effectively protect the frequency converter electric device from being burnt out and ensure the service life of the frequency converter electric device, and prevent the frequency converter from causing fire accidents due to the burnt out of the electric device, a protective measure for controlling and protecting the power supply circuit of the electric device by using temperature induction needs to be designed in the magnetic suspension frequency converter cabinet.
For some magnetic suspension frequency converters on the current market, because the interior of the magnetic suspension frequency converter is not provided with an effective control protection design for temperature, electric devices inside the frequency converter are burnt out due to overhigh temperature, and the burnt-out electric devices are frequently replaced, so that certain maintenance cost is increased in the aspect of after-sale maintenance, and some even more serious magnetic suspension frequency converters cause the electric devices inside the frequency converter to catch fire, further cause fire accidents, and seriously harm the personal safety.
Disclosure of Invention
One of the objectives of the present invention is to provide a temperature protection circuit for a magnetic suspension frequency converter, which can avoid the defects in the prior art, and can prevent the electronic components in the frequency converter cabinet from being damaged due to an over-high temperature, thereby reducing the workload of after-sales maintenance and the cost of after-sales maintenance, and meanwhile, can prevent the frequency converter from causing a fire accident due to the burning out of the electronic components, and further improve the safety and reliability of the frequency converter.
The purpose of the invention is realized by the following technical scheme:
the temperature protection circuit for the magnetic suspension frequency converter comprises a temperature control module, a first switch, an under-voltage control module and a second switch, wherein the temperature control module is electrically connected with a power module, the first switch is arranged in a path of the power module and a secondary measurement module, the under-voltage control module is electrically connected with the secondary measurement module, and the second switch is arranged in a path of the power module and a rectification inversion power module;
the temperature control module controls the first switch to carry out on-off operation based on whether the internal temperature of the frequency converter exceeds a temperature protection threshold value, the secondary detection module is in a power-off or power-on state due to the on-off of the first switch, and the under-voltage control module controls the second switch to carry out on-off operation based on the power-off or power-on state of the secondary detection module. When the temperature exceeds the threshold value, the secondary measurement module and the rectification inversion power module are disconnected, and the electronic components of the two modules can be protected, so that the electronic components in the frequency converter cabinet caused by overhigh temperature are prevented from being damaged, the workload of after-sale maintenance is reduced, the after-sale maintenance cost is reduced, meanwhile, the fire accident caused by the burning-out of the electronic components of the frequency converter can be prevented, and the safety and reliability of the frequency converter are further improved.
Furthermore, the temperature control module comprises a temperature controller and a relay, one end of the temperature controller is electrically connected with one end of the power supply module, the other end of the temperature controller is electrically connected with one end of the relay, the other end of the relay is electrically connected with the other end of the power supply module, and the first switch is a normally closed contact of the relay. Utilize the temperature controller to come the inside ambient temperature of response converter, reached the setting value of temperature controller when inside ambient temperature, the temperature controller triggers to make the relay action break off the power supply circuit of secondary survey module, realizes the protection of electrical part.
Furthermore, two ends of the temperature controller are electrically connected with the normally open contacts of the relay in parallel, and a third switch is further arranged between the power supply module and the temperature controller. The thermostat is reset when being opened, but because the normally open contact controlled by the relay is already in a closed state, the coil of the relay is always in an electric state, and then the normally closed contact of the input end of the control power supply is always in an open state, so that the electric device is always protected. The self-locking control contact of the temperature controller is added because the temperature controller is prevented from being disconnected and reset, and the electric device can be continuously protected, so that secondary damage caused by the fact that the frequency converter is powered on again is avoided. In this case, the temperature of the electric device can be recovered to normal only after a certain period of time. And manually disconnecting the third switch of the frequency converter again, resetting the relay, and starting the frequency converter to run after the power is re-electrified.
Further, the under-voltage control module is an under-voltage release electrically connected with the secondary measurement module;
the under-voltage release controls the second switch to be switched on or off based on the power-off or power-on state of the secondary test module. Because the temperature controller can respond to the inside ambient temperature of converter, reached the setting value of temperature controller when inside ambient temperature, the temperature controller can trigger and make the relay action break off the power supply circuit of secondary survey module, and the undervoltage tripper is based on the outage of secondary survey module and the disconnection of control second switch, realizes the protection of electrical part. Similarly, when the thermostat is disconnected and reset, but because the normally open contact controlled by the relay is already in a closed state, the coil of the relay is also always in an electric state, and then the normally closed contact of the input end of the control power supply is also always in an open state, so that the second switch is also always in an open state, and thus the electric device is always protected. The self-locking control contact of the temperature controller is added because the temperature controller is prevented from being disconnected and reset, and the electric device can be continuously protected, so that secondary damage caused by the fact that the frequency converter is powered on again is avoided. In this case, the temperature of the electric device can be recovered to normal only after a certain period of time. And manually disconnecting the third switch of the frequency converter again, resetting the relay, and starting the frequency converter to run after the power is re-electrified.
Further, the power module comprises an alternating current power input and a transformer, two phases of three-phase power of the alternating current power input are electrically connected with the transformer, and the third switch is arranged in a path between two phases of three-phase power of the alternating current power input and the transformer.
Furthermore, one end of the temperature controller is electrically connected with one end of the transformer of the power module, and the other end of the relay is electrically connected with the other end of the transformer of the power module.
Furthermore, two ends of the secondary measurement module are respectively electrically connected with two ends of the transformer, and the first switch is arranged in a path between the transformer and the secondary measurement module.
Further, the rectification inversion power module is electrically connected with the three-phase power input by the alternating current power supply, and the second switch is arranged in a path between the alternating current power input and the rectification inversion power module.
Further, a reactor is arranged in a path between the alternating current power supply input and the rectification and inversion power module.
The invention has the beneficial effects that: the invention discloses a temperature protection circuit for a magnetic suspension frequency converter, which comprises a temperature control module, a first switch, an under-voltage control module and a second switch, wherein the temperature control module is electrically connected with a power module, the first switch is arranged in a path of the power module and a secondary measurement module, the under-voltage control module is electrically connected with the secondary measurement module, and the second switch is arranged in a path of the power module and a rectification inversion power module. The temperature control module controls the first switch to be switched on or switched off based on whether the internal temperature of the frequency converter exceeds the temperature protection threshold value, the secondary detection module is determined to be in a power-off or power-on state due to the switching on or off of the first switch, and the under-voltage control module controls the second switch to be switched on or switched off based on the power-off or power-on state of the secondary detection module. When the temperature exceeds the threshold value, the secondary measurement module and the rectification inversion power module are disconnected, and the electronic components of the two modules can be protected, so that the electronic components in the frequency converter cabinet caused by overhigh temperature are prevented from being damaged, the workload of after-sale maintenance is reduced, the after-sale maintenance cost is reduced, meanwhile, the fire accident caused by the burning-out of the electronic components of the frequency converter can be prevented, and the safety and reliability of the frequency converter are further improved.
The second objective of the present invention is to avoid the disadvantages of the prior art and provide a magnetic levitation frequency converter, which uses the above temperature protection circuit for magnetic levitation frequency converter, because the temperature control module controls the first switch to perform on or off operation based on whether the internal temperature of the frequency converter exceeds the temperature protection threshold, because the on or off of the first switch determines that the secondary detection module is in the power-off or power-on state, and the under-voltage control module controls the second switch to perform on or off operation based on the power-off or power-on state of the secondary detection module. When the temperature exceeds the threshold value, the secondary measurement module and the rectification inversion power module are disconnected, and the electronic components of the two modules can be protected, so that the electronic components in the frequency converter cabinet caused by overhigh temperature are prevented from being damaged, the workload of after-sale maintenance is reduced, the after-sale maintenance cost is reduced, meanwhile, the fire accident caused by the burning-out of the electronic components of the frequency converter can be prevented, and the safety and reliability of the frequency converter are further improved.
Drawings
The invention is further illustrated by means of the attached drawings, but the embodiments in the drawings do not constitute any limitation to the invention, and for a person skilled in the art, other drawings can be derived on the basis of the following drawings without inventive effort.
Fig. 1 is a schematic circuit diagram of a temperature protection circuit for a magnetic levitation frequency converter according to the invention.
Fig. 2 is a flow chart of the operation of the temperature protection circuit for the magnetic suspension frequency converter of the invention.
Wherein the reference numbers are as follows: a temperature control module 10, an under-voltage control module 20 and a power supply module 30.
Detailed Description
The invention is further described with reference to the following examples.
Example 1
As shown in fig. 1, the temperature protection circuit for a magnetic levitation frequency converter of this embodiment includes a temperature control module 10, a first switch S1, an under-voltage control module 20, and a second switch QF2, where the temperature control module 10 is electrically connected to a power module 30, the first switch S1 is disposed in a path between the power module 30 and a secondary measurement module, the under-voltage control module 20 is electrically connected to the secondary measurement module, and the second switch QF2 is disposed in a path between the power module 30 and a rectification and inversion power module;
the temperature control module 10 controls the first switch S1 to be turned on or off based on whether the internal temperature of the inverter exceeds a temperature protection threshold, the secondary test module is in a power-off or power-on state due to the on or off of the first switch S1, and the under-voltage control module 20 controls the second switch QF2 to be turned on or off based on the power-off or power-on state of the secondary test module. When the temperature exceeds the threshold value, the secondary measurement module and the rectification inversion power module are disconnected, and the electronic components of the two modules can be protected, so that the electronic components in the frequency converter cabinet caused by overhigh temperature are prevented from being damaged, the workload of after-sale maintenance is reduced, the after-sale maintenance cost is reduced, meanwhile, the fire accident caused by the burning-out of the electronic components of the frequency converter can be prevented, and the safety and reliability of the frequency converter are further improved.
The both ends of temperature controller KT1 with the normally open contact S2 of relay KA1 is parallelly connected and is connected electrically, power module 30 with still be provided with third switch QF1 between the temperature controller KT 1. The temperature controller KT1 is reset by opening, but because the normally open contact S2 controlled by the relay KA1 is already in a closed state, the coil of the relay KA1 is always in an energized state, and the normally closed contact of the control power input is always in an open state, so that the electric device is always protected. The self-locking control contact of the temperature controller KT1 is added because the temperature controller KT1 is prevented from being disconnected and reset, and the electric device can be continuously protected, so that the secondary damage caused by the fact that the frequency converter is connected with the power supply again is avoided. In this case, the temperature of the electric device can be recovered to normal only after a certain period of time. The third switch QF1 of the frequency converter is manually disconnected again, the relay KA1 can be reset, and the frequency converter can be started to operate after being electrified again.
The undervoltage control module 20 is an undervoltage release electrically connected with the secondary measurement module;
the under-voltage release controls the second switch QF2 to be switched on or off based on the power-off or power-on state of the secondary test module. Because the inside ambient temperature of temperature controller KT1 can the response converter, reached the setting value of temperature controller KT1 when inside ambient temperature, the temperature controller can trigger and make relay KA1 action disconnection secondary survey the power supply circuit of module, and the undervoltage release is based on the outage of secondary survey the module and control the disconnection of second switch QF2, realizes the protection of electrical part. Similarly, when the temperature controller KT1 is turned off and reset, but because the normally open contact S2 controlled by the relay KA1 is already in a closed state, the coil of the relay KA1 is always in an energized state, and then the normally closed contact of the control power input end is always in an open state, so that the second switch QF2 is also always in an open state, and thus the electric device is always protected. The self-locking control contact of the temperature controller KT1 is added because the temperature controller KT1 is prevented from being disconnected and reset, and the electric device can be continuously protected, so that the secondary damage caused by the fact that the frequency converter is connected with the power supply again is avoided. In this case, the temperature of the electric device can be recovered to normal only after a certain period of time. The third switch QF1 of the frequency converter is manually disconnected again, the relay KA1 can be reset, and the frequency converter can be started to operate after being electrified again.
The power module 30 comprises a 380V alternating current power input and a transformer T1, wherein two phases of three-phase electricity of the alternating current power input are electrically connected with the transformer T1, and the third switch QF1 is arranged in a path of two phases of three-phase electricity of the alternating current power input and the transformer T1.
One end of the temperature controller KT1 is electrically connected with one end of the transformer T1 of the power module 30, and the other end of the relay KA1 is electrically connected with the other end of the transformer T1 of the power module 30.
Two ends of the secondary test module are respectively and electrically connected with two ends of the transformer T1, and the first switch S1 is arranged in a passage of the transformer T1 and the secondary test module.
The rectification inversion power module is electrically connected with three phases of power input by the alternating current power supply, and the second switch QF2 is arranged in a passage between the alternating current power supply input and the rectification inversion power module.
And a reactor L1 is also arranged in a path between the alternating current power supply input and the rectification and inversion power module.
The working process of the temperature protection circuit for the magnetic suspension frequency converter is as shown in figure 2, when the inside of the frequency converter is abnormally overhigh, the temperature controller KT1 detects that the temperature reaches a preset value and acts, the coil of the relay KA1 is electrified to be normally closed, the normally open contact acts to control the normally closed contact of the power input of the secondary measurement module to be disconnected, the secondary measurement module is protected, meanwhile, the under-voltage tripper is electrified to disconnect the second switch QF2, the frequency converter stops running, the rectification and inversion power module is protected, because two ends of the temperature controller KT1 are electrically connected with the normally open contact S2 of the relay KA1 in parallel, when the coil of the relay KA1 is electrified to be normally closed and the normally open contact acts, the normally open contact S2 with the self-locking function of the temperature controller KT1 is triggered at the same time, the temperature controller KT1 is self-locked, the relay KA1 is ensured to be always in the electrified state, the, the coil of relay KA1 can be de-energized and thus reset.
The protection circuit is designed by detecting the temperature by the temperature controller to trigger the protection of the circuit, so that the protection circuit is also applicable to other devices with large heat productivity of internal electric devices such as high-power frequency converters, starting cabinets, high-speed motor drivers and power distribution cabinets except for the magnetic suspension frequency converters. Not only has wide application range, but also has very obvious protection effect.
Example 2
The present embodiment provides a magnetic levitation frequency converter using the temperature protection circuit for a magnetic levitation frequency converter described in embodiment 1, since the temperature control module 10 controls the first switch S1 to perform on or off operation based on whether the internal temperature of the frequency converter exceeds the temperature protection threshold, the secondary test module is in a power-off or power-on state due to the on or off of the first switch S1, and the under-voltage control module 20 controls the second switch QF2 to perform on or off operation based on the power-off or power-on state of the secondary test module. When the temperature exceeds the threshold value, the secondary measurement module and the rectification inversion power module are disconnected, and the electronic components of the two modules can be protected, so that the electronic components in the frequency converter cabinet caused by overhigh temperature are prevented from being damaged, the workload of after-sale maintenance is reduced, the after-sale maintenance cost is reduced, meanwhile, the fire accident caused by the burning-out of the electronic components of the frequency converter can be prevented, and the safety and reliability of the frequency converter are further improved.
Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention, and not for limiting the protection scope of the present invention, although the present invention is described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions can be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.
Claims (6)
1. A temperature protection circuit for a magnetic suspension frequency converter is characterized in that: the temperature control module is electrically connected with a power module, the first switch is arranged in a path of the power module and a secondary measurement module, the under-voltage control module is electrically connected with the secondary measurement module, and the second switch is arranged in a path of the power module and a rectification inversion power module;
the temperature control module controls the first switch to carry out on-off operation based on whether the internal temperature of the frequency converter exceeds a temperature protection threshold value, the secondary detection module is in a power-off or power-on state due to the on-off of the first switch, and the under-voltage control module controls the second switch to carry out on-off operation based on the power-off or power-on state of the secondary detection module;
the temperature control module comprises a temperature controller and a relay, one end of the temperature controller is electrically connected with one end of the power supply module, the other end of the temperature controller is electrically connected with one end of the relay, the other end of the relay is electrically connected with the other end of the power supply module, the first switch is a normally closed contact of the relay, two ends of the temperature controller are electrically connected with a normally open contact of the relay in parallel, and a third switch is arranged between the power supply module and the temperature controller;
the power module comprises an alternating current power supply input and a transformer, wherein two phases of three-phase power input by the alternating current power supply are electrically connected with the transformer, the third switch is arranged in a passage between the two phases of the three-phase power input by the alternating current power supply and the transformer, and a reactor is further arranged in the passage between the alternating current power supply input and the rectification inversion power module.
2. A temperature protection circuit for a magnetic levitation frequency converter as claimed in claim 1, characterized in that: the under-voltage control module is an under-voltage release electrically connected with the secondary measurement module;
the under-voltage release controls the second switch to be switched on or off based on the power-off or power-on state of the secondary test module.
3. A temperature protection circuit for a magnetic levitation frequency converter as claimed in claim 1, characterized in that: one end of the temperature controller is electrically connected with one end of the transformer of the power module, and the other end of the relay is electrically connected with the other end of the transformer of the power module.
4. A temperature protection circuit for a magnetic levitation frequency converter as claimed in claim 1, characterized in that: the two ends of the secondary testing module are respectively and electrically connected with the two ends of the transformer, and the first switch is arranged in the transformer and a path of the secondary testing module.
5. A temperature protection circuit for a magnetic levitation frequency converter as claimed in claim 1, characterized in that: the rectification inversion power module is electrically connected with three phases of power input by the alternating current power supply, and the second switch is arranged in a passage between the alternating current power supply input and the rectification inversion power module.
6. A magnetic suspension frequency converter is characterized in that: comprising a temperature protection circuit for a magnetically levitated frequency converter according to any one of claims 1 to 5.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911093359.7A CN110932230B (en) | 2019-11-11 | 2019-11-11 | Temperature protection circuit for magnetic suspension frequency converter and magnetic suspension frequency converter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911093359.7A CN110932230B (en) | 2019-11-11 | 2019-11-11 | Temperature protection circuit for magnetic suspension frequency converter and magnetic suspension frequency converter |
Publications (2)
| Publication Number | Publication Date |
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| CN110932230A CN110932230A (en) | 2020-03-27 |
| CN110932230B true CN110932230B (en) | 2021-03-02 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201911093359.7A Active CN110932230B (en) | 2019-11-11 | 2019-11-11 | Temperature protection circuit for magnetic suspension frequency converter and magnetic suspension frequency converter |
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Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6841983B2 (en) * | 2002-11-14 | 2005-01-11 | Fyre Storm, Inc. | Digital signal to pulse converter and method of digital signal to pulse conversion |
| CN102006010A (en) * | 2010-12-23 | 2011-04-06 | 湖南科技大学 | Variable frequency driving control method and device for high-power mine hoist |
| CN202084910U (en) * | 2011-05-26 | 2011-12-21 | 江苏力普电子科技有限公司 | High-voltage frequency conversion device capable of overheating protection |
| CN203522154U (en) * | 2013-09-26 | 2014-04-02 | 武汉钢铁(集团)公司 | Over-current protective device of frequency converter |
| CN205283377U (en) * | 2016-01-14 | 2016-06-01 | 吕玉波 | 10kv high -voltage frequency converters speed adjusting device |
| CN110242609A (en) * | 2019-07-12 | 2019-09-17 | 天津市天鼓机械制造有限公司 | Magnetic suspension air blower temperature control device |
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