CN104467384A - Frequency converter peak voltage absorbing device, method and system - Google Patents
Frequency converter peak voltage absorbing device, method and system Download PDFInfo
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- CN104467384A CN104467384A CN201310425015.8A CN201310425015A CN104467384A CN 104467384 A CN104467384 A CN 104467384A CN 201310425015 A CN201310425015 A CN 201310425015A CN 104467384 A CN104467384 A CN 104467384A
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- peak voltage
- motor
- frequency converter
- electricity
- heating
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/12—Arrangements for reducing harmonics from ac input or output
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Control Of Ac Motors In General (AREA)
Abstract
The invention discloses a frequency converter peak voltage absorbing device, method and system. The absorbing device is connected in parallel with a motor. The absorbing device comprises a peak voltage detector, a switch element, and an electric energy-heat energy converter, wherein the switch element is connected between a power input end of the motor and the electric energy-heat energy converter; the peak voltage detector detects the peak voltage of the power input end of the motor, when the peak voltage exceeds a detection threshold value, the peak voltage detector triggers the switch element to be conducted, so the electric energy-heat energy converter can receive the peak voltage of the power input end of the motor for converting into heat energy. The frequency converter peak voltage absorbing device is simple in structure, low in cost and convenient to install, does not generate voltage drop, does not affect the torque of the motor, at the same time, can effectively eliminate damage caused by a frequency converter to a motor stator winding, and substantially absorbs the peak voltage for converting into the heat energy for dissipation.
Description
Technical field
The present invention relates to electric motor protecting field, particularly relate to a kind of frequency converter peak voltage absorption plant, method and system.
Background technology
In the prior art, a lot of occasion needs to adjust the rotating speed of alternating current machine.Particularly in recent years, energy-saving and cost-reducing requirement is improved constantly, very general by the situation of the equipment such as Frequency Converter Control blower fan, water pump, air compressor machine.
But the voltage waveform due to transducer drive motor is not sinusoidal wave, but PWM voltage waveform, this waveform can produce serious damage to the stator winding of motor and bearing.
The reason of the PWM voltage waveform damage motor stator winding that frequency converter exports is, pwm pulse voltage reflects in motor side, incident wave superposes with reflected wave, formation amplitude is more than the peak voltage of PWM voltage amplitude 2 times, this peak voltage constantly acts in motor stator winding, causes the turn-to-turn insulation of winding to puncture.
There are some technology to address this problem at present, mainly at the output of frequency converter, sine wave filter or du/dt filter are installed.
The effect of sine wave filter is that PWM voltage waveform is shaped to sine wave, so just naturally eliminates the peak voltage produced in motor side, plays the effect of protection motor.
The effect of du/dt filter is similar to sine wave filter, but it is not that PWM voltage waveform is shaped to sine wave completely, but extends the rising edge of pulse, thus reduces peak voltage.
The major defect of these solutions above-mentioned is:
When power is larger, the volume of filter will be corresponding comparatively large, and cost is higher.And sine wave filter is owing to existing larger voltage drop, the torque of motor also can be affected.
Summary of the invention
The invention discloses a kind of frequency converter peak voltage absorption plant, method and system, for absorbing peak voltage, at a low price, effectively eliminating frequency converter to the damage of motor stator winding.
The invention discloses a kind of frequency converter peak voltage absorption plant, frequency converter is connected with motor, and this absorption plant is connected with this motor parallel, and this absorption plant comprises:
Peak voltage detector, switch element and energy device for electricity and heating;
This switch element is connected between the power input of this motor and this energy device for electricity and heating;
This peak voltage detector detects the peak voltage of the power input of this motor, when this peak voltage exceedes detection threshold, this peak voltage detector triggers this switching elements conductive, makes this energy device for electricity and heating receive the peak voltage of the power input of this motor, is converted to heat energy.
Between this peak voltage detector and power input of this motor, be provided with a high-speed pulse buffer cell, this high-speed pulse buffer cell is used for this peak voltage temporary.
This peak voltage detector is TVS diode.This switch element is igbt transistor.This energy device for electricity and heating is resistance.One fin is arranged on this energy device for electricity and heating, for heat radiation.
This absorption plant is connected to the tie point between frequency converter and this motor, and the cable length between this tie point and this absorption plant is less than or equal to 3 meters, and this tie point is less than or equal to 8 meters apart from the distance of the terminals of this motor.
This device also comprises temperature-detecting device, and for detecting the temperature of this energy device for electricity and heating, when temperature exceedes predetermined threshold value, this temperature-detecting device triggers this peak voltage detector and improves this detection threshold.
The invention also discloses a kind of electric system, comprising:
Frequency converter; Motor, is connected with this frequency converter; Described frequency converter peak voltage absorption plant.
The invention also discloses a kind of frequency converter peak voltage absorption process, comprise: utilize peak voltage detector to detect the peak voltage of the power input of this motor, if this peak voltage exceedes detection threshold, received the peak voltage of the power input of this motor by an energy device for electricity and heating and be converted into heat energy.
Detect the temperature of this energy device for electricity and heating, when temperature exceedes predetermined threshold value, improve this detection threshold.
The structure of frequency converter peak voltage absorption plant of the present invention is simple, cost is low, installation is convenient, can not produce voltage drop, does not affect the torque of motor, maintains it and normally works.Meanwhile, frequency converter peak voltage absorption plant of the present invention effectively can eliminate the damage of frequency converter to motor stator winding, significantly absorbs peak voltage, is converted to heat dissipation and falls.
Accompanying drawing explanation
Figure 1 shows that the structural representation of electric system of the present invention;
Figure 2 shows that the structural representation of absorption plant of the present invention;
Figure 3 shows that the structural representation of the absorption plant of another embodiment of the present invention;
Figure 4 shows that the structural representation of the absorption plant of another embodiment of the present invention;
Figure 5 shows that the displaying principle schematic diagram of this operating status display apparatus;
Figure 6 shows that the flow chart of a kind of frequency converter peak voltage absorption process of the present invention.
Embodiment
The specific embodiment of the present invention is introduced below in conjunction with accompanying drawing and embodiment.
In order to effectively eliminate the peak voltage of frequency converter generation to the damage of motor stator winding, the present invention proposes a kind of frequency converter peak voltage absorber (Surge VoltageAbsorber, SVA) for absorbing this peak voltage.
Be illustrated in figure 1 the structural representation of electric system 100 of the present invention.Electric system 100 comprises frequency converter 10, motor 20 and frequency converter peak voltage absorption plant 30(hereinafter referred to as absorption plant).This absorption plant 30 is connected in parallel with this motor 20.This motor 20 is alternating current machine.Absorption plant 30 detects the peak voltage of motor 20 power input, when absorption plant 30 detects the detection threshold that this peak voltage presets more than, absorption plant 30 automatically produces a very low impedance, the energy absorption of peak voltage is fallen, and converts electric energy to thermal energy consumption and dissipate.
Be illustrated in figure 2 the structural representation of absorption plant 30 of the present invention.This absorption plant 30 comprises: peak voltage detector 31, switch element 32 and energy device for electricity and heating 33.This switch element 32 is connected between the power input of this motor and this energy device for electricity and heating 33.This peak voltage detector 31 connects the power input of this motor 20.This peak voltage detector 31 detects the peak voltage of the power input of this motor 20, when this peak voltage exceedes the detection threshold preset in this peak voltage detector 31, this peak voltage detector 31 triggers this switch element 32 conducting, make this energy device for electricity and heating 33 receive the peak voltage of the power input of this motor, be converted into heat energy.
Specifically, this peak voltage detector 31 can be selected TVS diode to realize.Switch element 32 can adopt igbt transistor to realize.Use resistance as this energy device for electricity and heating 33.This peak voltage detector 31 is connected with this switch element 32.
When peak voltage does not exceed the detection threshold of this TVS diode, this TVS diode remain off, has higher impedance, does not have electric current to flow through, and can not produce pressure drop, also would not affect the normal operation of frequency converter.Igbt transistor is remain off also, has very high impedance, can not affect the normal work of circuit.
When peak voltage exceedes the detection threshold of this TVS diode, this TVS diode conducting, then the electric current now flowing through the sampling resistor of this TVS diode will significantly increase, then the voltage on the sampling resistor of this TVS diode also can significantly increase.Because this TVS diode is connected with igbt transistor, the output of this TVS diode can be connected with the gate terminal of igbt transistor, thus makes the gate terminal of igbt transistor receive high voltage, triggers this igbt transistor conducting.When this igbt transistor conducting, himself impedance is very little.The TVS diode of conducting and igbt transistor make electric energy flow into this resistance, by the resistance evolution of heat, to discharge the energy of this peak voltage smoothly in space, realize the absorption to peak voltage.
Specifically, frequency converter of the present invention is low voltage frequency converter, and its input voltage can select 380V, 690V, 1080V.For 380V, when TVS pipe is ended, the TVS pipe reverse leakage current selected is for being less than 5 μ A, and calculating resistance value is 380V/5 μ A=76M Ω, and resistance value is comparatively large, can not affect the normal operation of frequency converter.When TVS pipe conducting, the TVS pipe On current of different voltage specification is different.Carry out current limliting to TVS pipe on-state current in the present invention, during TVS conducting, maximum current is less than 10mA.Therefore, no matter when cut-off and conducting, TVS diode can be ignored on the impact of frequency converter work.
When the input voltage of low voltage frequency converter selects 380V, 690V, 1080V respectively, the resistance value of this energy device for electricity and heating 33 can select 100 Ω, 200 Ω, 300 Ω respectively.
This resistance of this energy device for electricity and heating 33 can select aluminum casing resistor, further, also can be arranged on this energy device for electricity and heating by a fin, to be dissipated the heat that this resistance produces by this fin.
In addition, because the absorption of absorption plant 30 pairs of peak voltages needs conducting TVS diode successively, igbt transistor, so the running of absorption plant 30 needs certain response time.And for the very short peak voltage of rising edge, its form is high-speed pulse, and its cycle is far below the response time of absorption plant 30.In order to the peak voltage very short to rising edge has good inhibition, in another embodiment of the invention, a high-speed pulse buffer cell is installed in the front end of peak voltage detector, the energy temporary cache of the peak voltage of high-speed pulse is got up, after device 30 to be absorbed is started working, release temporary energy, its structural representation as shown in Figure 3, is provided with high-speed pulse buffer cell 34 between this peak voltage detector and power input of this motor again.
This high-speed pulse buffer cell 34 can form, for the peak voltage of temporary transducer drive motor by by 15 μ F and 3 0.01 μ F electric capacity.
Also can operating status display apparatus be provided with between this peak voltage detector 31 and power input of this motor, with the running status of the absorption plant 30 of pointing out user current, follow-up detailed description.
In addition, consult shown in Fig. 1, when installing this absorption plant 30, this absorption plant 30 is connected to the tie point A between frequency converter 10 and this motor 20, cable length AC between this tie point A and this absorption plant 30 need be less than or equal to 3 meters, be longer than 3 meters of effects that can affect peak voltage and absorb, this tie point A need be less than or equal to 8 meters apart from the distance AB of the terminals B of this motor, is longer than 8 meters of meetings and produces new peak voltage at terminals.In addition, the driving cable between frequency converter and motor also has impact to peak voltage.Such as, when the input voltage of frequency converter is 380V, if the driving cable length between frequency converter and motor is more than 30 meters, this peak voltage may rise to more than 1200V.
Be illustrated in figure 4 the structural representation of the absorption plant of another embodiment of the present invention.
This absorption plant 30 also comprises temperature-detecting device 35, and for detecting the temperature of this energy device for electricity and heating 33, when temperature is more than a predetermined threshold value, this temperature-detecting device triggers this peak voltage detector and improves this detection threshold.
Specifically, temperature-detecting device 35 can be close to this energy device for electricity and heating 33 and arrange, to measure the temperature of this energy device for electricity and heating 33.For the input voltage of frequency converter for 380V, the detection threshold of peak voltage detector is preset as 700V, and when absorption plant 30 brings into operation, motor side is almost all absorbed higher than the peak voltage of 700V.
Temperature-detecting device 35 monitors the temperature of energy device for electricity and heating 33 at any time, if find that this temperature is higher than 60 DEG C, temperature-detecting device 35 sends adjustment signal to peak voltage detector 31, peak voltage detector is after receiving adjustment signal, detection threshold is improved a predetermined value, such as detection threshold is risen to 750V automatically, to reduce the energy of absorption.This process also can realize in the following manner, and peak voltage detector 31 comprises the different TVS diode of the detection threshold of multiple parallel connection, but the same time only ensures between the power input that a TVS diode is connected to motor and switch element 32.After peak voltage detector 31 receives adjustment signal, disconnection detection threshold value is the TVS diode of 700V and the electric connection of other parts of circuit, then sets up the electric connection that detection threshold is the TVS diode of 750V and the power input of motor and switch element 32.Improve other implementations of detection threshold also within the scope of the invention.After detection threshold rises to 750V automatically, motor side is almost all absorbed higher than the peak voltage of 750V, that is, the peak voltage between 700-750V is not absorbed, and decreases the energy of absorption.And temperature-detecting device 35 still continues the temperature monitoring energy device for electricity and heating 33, if find that this temperature is higher than 70 DEG C, temperature-detecting device 35 sends adjustment signal to peak voltage detector 31, detection threshold is risen to 800V by peak voltage detector automatically, now, motor side is almost all absorbed higher than the peak voltage of 800V.
In more specifically embodiment, absorption plant of the present invention is also provided with operating status display apparatus, is illustrated in figure 5 the displaying principle schematic diagram of this operating status display apparatus.
This operating status display apparatus comprises and powers up work light, peak absorbing lamp, housing high temperature lamps and full-load run lamp.Absorption plant 30 also has metal shell, and this operating status display apparatus is just arranged on the panel of metal shell.
Temperature-detecting device 35 can be temperature sensor, particularly in order to detect 60 DEG C and 70 DEG C respectively, can utilize voltage divider, connects two temperature sensors respectively, to detect 60 DEG C and 70 DEG C respectively.
When absorption plant 30 energising is started working, power up work light and light, start working to point out user's absorption plant.When peak voltage detector detects that the power input of this motor exists peak voltage (700V), and when falling its energy by resistance absorption, peak absorbing lamp is lighted, and to point out the normal operation of user's absorption plant, has sponged part peak voltage.When temperature sensor detects that the temperature of energy device for electricity and heating has reached 60 DEG C, housing high temperature lamps is lighted, a large amount of peak voltage is converted to heat energy to point out user's absorption plant 30, the temperature of housing is higher, avoid contact housing in order to avoid cause to burn, point out this detection threshold of user to rise to 750V simultaneously.When temperature sensor detects that the temperature of energy device for electricity and heating has reached 70 DEG C, full-load run lamp is lighted, all play to point out the energy absorption capability of user's absorption plant 30, this detection threshold rises to 800V, preferably reduce the carrier frequency of frequency converter, or improve the radiating condition of peak voltage absorber.
So, user according to the operating status display apparatus of absorption plant 30, can understand the current state of absorption plant 30, to take corresponding adjustment or security protection.
Be illustrated in figure 6 according to above embodiment, the flow chart of a kind of frequency converter peak voltage absorption process disclosed in this invention.
Step 1, utilizes peak voltage detector to detect the peak voltage of the power input of this motor;
Step 2, judges whether to exceed detection threshold, if not, performs step 1, if so, performs step 3;
Step 3, is received the peak voltage of the power input of this motor and is converted into heat energy by an energy device for electricity and heating.
The method also comprises: the temperature detecting this energy device for electricity and heating at any time, when temperature exceedes predetermined threshold value, improves this detection threshold.
The structure of frequency converter peak voltage absorption plant of the present invention is simple, cost is low, installation is convenient, can not produce voltage drop, does not affect the torque of motor, maintains it and normally works.Meanwhile, frequency converter peak voltage absorption plant of the present invention effectively can eliminate the damage of frequency converter to motor stator winding, significantly absorbs peak voltage, is converted to heat dissipation and falls.
Claims (11)
1. a frequency converter peak voltage absorption plant, frequency converter is connected with motor, it is characterized in that, this absorption plant is connected with this motor parallel, and this absorption plant comprises:
Peak voltage detector, switch element and energy device for electricity and heating;
This switch element is connected between the power input of this motor and this energy device for electricity and heating;
This peak voltage detector detects the peak voltage of the power input of this motor, when this peak voltage exceedes detection threshold, this peak voltage detector triggers this switching elements conductive, makes this energy device for electricity and heating receive the peak voltage of the power input of this motor, is converted to heat energy.
2. device as claimed in claim 1, is characterized in that, be provided with a high-speed pulse buffer cell between this peak voltage detector and power input of this motor, and this high-speed pulse buffer cell is used for this peak voltage temporary.
3. device as claimed in claim 1, it is characterized in that, this peak voltage detector is TVS diode.
4. device as claimed in claim 1, it is characterized in that, this switch element is igbt transistor.
5. device as claimed in claim 1, it is characterized in that, this energy device for electricity and heating is resistance.
6. device as claimed in claim 5, it is characterized in that, a fin is arranged on this energy device for electricity and heating, for heat radiation.
7. device as claimed in claim 1, it is characterized in that, this absorption plant is connected to the tie point between frequency converter and this motor, and the cable length between this tie point and this absorption plant is less than or equal to 3 meters, and this tie point is less than or equal to 8 meters apart from the distance of the terminals of this motor.
8. device as claimed in claim 1, it is characterized in that, this device also comprises temperature-detecting device, for detecting the temperature of this energy device for electricity and heating, when temperature exceedes predetermined threshold value, this temperature-detecting device triggers this peak voltage detector and improves this detection threshold.
9. an electric system, is characterized in that, comprising:
Frequency converter;
Motor, is connected with this frequency converter;
As the frequency converter peak voltage absorption plant as described in arbitrary in claim 1-8.
10. a frequency converter peak voltage absorption process, is characterized in that, comprising:
Utilize peak voltage detector to detect the peak voltage of the power input of this motor, if this peak voltage exceedes detection threshold, received the peak voltage of the power input of this motor by an energy device for electricity and heating and be converted into heat energy.
11. methods as claimed in claim 10, is characterized in that, also comprise:
Detect the temperature of this energy device for electricity and heating, when temperature exceedes predetermined threshold value, improve this detection threshold.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310425015.8A CN104467384A (en) | 2013-09-17 | 2013-09-17 | Frequency converter peak voltage absorbing device, method and system |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310425015.8A CN104467384A (en) | 2013-09-17 | 2013-09-17 | Frequency converter peak voltage absorbing device, method and system |
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| Publication Number | Publication Date |
|---|---|
| CN104467384A true CN104467384A (en) | 2015-03-25 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201310425015.8A Pending CN104467384A (en) | 2013-09-17 | 2013-09-17 | Frequency converter peak voltage absorbing device, method and system |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113346725A (en) * | 2020-02-18 | 2021-09-03 | 维谛技术有限公司 | Peak voltage absorption circuit |
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| EP1511148A2 (en) * | 2003-08-27 | 2005-03-02 | Fanuc Ltd | Surge voltage suppressor |
| JP2006333564A (en) * | 2005-05-24 | 2006-12-07 | Toshiba Mitsubishi-Electric Industrial System Corp | Surge absorber |
| CN202160101U (en) * | 2011-08-03 | 2012-03-07 | 重庆瑜欣平瑞电子有限公司 | Rectifying circuit for input end of inverter controller in portable generator |
| CN102608445A (en) * | 2010-12-17 | 2012-07-25 | 通用电气航空系统有限公司 | Testing of a transient voltage protection device |
| CN203522514U (en) * | 2013-09-17 | 2014-04-02 | 北京计算机技术及应用研究所 | Frequency converter peak voltage absorbing device and system |
-
2013
- 2013-09-17 CN CN201310425015.8A patent/CN104467384A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1511148A2 (en) * | 2003-08-27 | 2005-03-02 | Fanuc Ltd | Surge voltage suppressor |
| JP2006333564A (en) * | 2005-05-24 | 2006-12-07 | Toshiba Mitsubishi-Electric Industrial System Corp | Surge absorber |
| CN102608445A (en) * | 2010-12-17 | 2012-07-25 | 通用电气航空系统有限公司 | Testing of a transient voltage protection device |
| CN202160101U (en) * | 2011-08-03 | 2012-03-07 | 重庆瑜欣平瑞电子有限公司 | Rectifying circuit for input end of inverter controller in portable generator |
| CN203522514U (en) * | 2013-09-17 | 2014-04-02 | 北京计算机技术及应用研究所 | Frequency converter peak voltage absorbing device and system |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113346725A (en) * | 2020-02-18 | 2021-09-03 | 维谛技术有限公司 | Peak voltage absorption circuit |
| CN113346725B (en) * | 2020-02-18 | 2023-09-01 | 维谛新能源有限公司 | Peak voltage absorbing circuit |
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Application publication date: 20150325 |
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