For eliminating the system of variable-frequency motor peak voltage
Technical field
The utility model relates to electric power safety field, in particular it relates to a kind of for eliminating variable-frequency motor peak voltage
System.
Background technology
Variable-frequency motor peak voltage can make the dielectric strength of motor decline, and causes the insulation harm of motor winding, right
Variable-frequency motor is very harmful.For peak voltage problem, motor protection method conventional at present has following three kinds:
1) output at frequency converter installs reactor: this measure is the most frequently used, but this method is for shorter electricity
Cable (less than 30 meters) has certain effect, but effect is not ideal enough sometimes, owing to being to be used in series, can form pressure drop thus affect
The torque output of motor, and bearing cannot be protected;
2) output at frequency converter installs dv/dt wave filter: this measure is applicable to the field less than 300 meters for the cable length
Closing, effect has had obvious improvement, but price is slightly above reactor, and volume is relatively big, and cannot protect bearing;
3) output at frequency converter installs sine wave filter: pulse voltage is become sine voltage, makes motor
Under conditions of being operated in identical with power-frequency voltage, the problem of peak voltage can be well solved, but cost is too high, and volume is very
Greatly, especially cannot install at Air-Cooling Island variable-frequency motor scene, and bearing cannot be protected.
Utility model content
The purpose of this utility model is to provide a kind of system for eliminating variable-frequency motor peak voltage, and this is used for eliminating change
Frequently the system price of motor peak voltage is cheap, volume is little, stable performance, can protect motor bearings and to administer peak voltage
Problem effect is notable.
To achieve these goals, the utility model provides a kind of system for eliminating variable-frequency motor peak voltage, should
System include the detection device on the cable that is arranged between variable-frequency motor and frequency converter and energy absorbing device and with described
The control device that detection device and described energy absorbing device connect, wherein, described detection device, for the described electricity of real-time detection
Voltage amplitude on cable, concurrent power transmission pressure amplitude degrees of data;And described control device is for receiving from described detection device
Voltage amplitude data, when the voltage amplitude data receiving are more than or equal to voltage amplitude threshold value, control described energy absorption
Device absorbs the energy of the peak voltage on described cable.
Preferably, this system also includes energy conversion device, and this energy conversion device is connected with described energy absorbing device,
For receiving the energy of the peak voltage that described energy absorbing device is released, and the energy by described peak voltage is converted into heat
Energy.
Preferably, this system also includes the control valve being positioned between described energy absorbing device and described energy conversion device
Door.
Preferably, described control device is also connected with described control valve, is used for receiving described energy absorbing device and sends
Energy datum, described energy datum more than or equal to energy datum threshold value when control described control valve open.
Preferably, this system also includes temperature detector, is used for detecting the temperature of described energy conversion device, and sends temperature
Degrees of data;Described control device is connected with described temperature detector and described control valve, is used for receiving described temperature data, when
Described temperature data described control device control described control valve closing more than or equal to during temperature threshold.
Preferably, this system also includes current sinking device, installs on the cables., is used for absorbing shaft current.
Preferably, described current sinking device and described energy absorbing device become one.
By technique scheme, use the system for eliminating variable-frequency motor peak voltage that the utility model provides,
This system includes detection device, energy absorbing device and control device.Detection device is utilized to detect the voltage amplitude on cable in real time
Degree, concurrent power transmission pressure amplitude degrees of data, utilize control device to receive the voltage amplitude data of self-test device, and will receive
Voltage amplitude data compare with voltage amplitude threshold value, when the voltage amplitude data receiving are more than or equal to voltage amplitude threshold
During value, the energy of the peak voltage on control device control energy absorbing device absorbing cable.What the utility model provided is used for
Eliminate variable-frequency motor peak voltage system price cheap, volume is little, stable performance, can protect motor bearings and to administer point
Peak voltage problem effect is notable.
Other feature and advantage of the present utility model will be described in detail in detailed description of the invention part subsequently.
Brief description
Accompanying drawing is used to provide and is further appreciated by of the present utility model, and constitutes a part for specification, and following
Detailed description of the invention be used for explaining the utility model together, but be not intended that to restriction of the present utility model.In the accompanying drawings:
Fig. 1 is the structural representation of the system for eliminating variable-frequency motor peak voltage that the utility model provides;
Fig. 2 is that the structure of the system for eliminating variable-frequency motor peak voltage that the utility model one embodiment provides is shown
It is intended to.
Description of reference numerals
1 detection device 2 energy absorbing device
3 control device 4 energy conversion devices
5 control valve 6 temperature detectors
7 current sinking device.
Detailed description of the invention
Below in conjunction with accompanying drawing, detailed description of the invention of the present utility model is described in detail.It should be appreciated that herein
Described detailed description of the invention is merely to illustrate and explains the utility model, is not limited to the utility model.
Fig. 1 is the structural representation of the system for eliminating variable-frequency motor peak voltage that the utility model provides.Such as Fig. 1
Shown in, a kind of system for eliminating variable-frequency motor peak voltage includes the cable being arranged between variable-frequency motor and frequency converter
Detection device 1 and energy absorbing device 2 and fill with described detection device 1 and the control that is connected of described energy absorbing device 2
Putting 3, wherein, described detection device 1, for the voltage amplitude on the described cable of real-time detection, concurrent power transmission pressure amplitude degrees of data;With
And described control device 3 is for receiving the voltage amplitude data from described detection device 1, when the voltage amplitude data receiving
During more than or equal to voltage amplitude threshold value, control described energy absorbing device 2 and absorb the energy of the peak voltage on described cable.
Owing to detection device 1 and energy absorbing device 2 are both connected on the cable with frequency converter for the variable-frequency motor, in order to not produce
Giving birth to voltage drop, testing circuit 1 and absorption plant 2 can select not to be connected on cable, and are in from cable the volume drawn
On outer branch road.Detection device detects the voltage amplitude on cable in real time, and concurrent power transmission pressure amplitude degrees of data gives control device 3, control
Device 3 receives the voltage amplitude data of self-test device 1, and contrast potential amplitude data and voltage amplitude threshold value, at voltage
When amplitude data is more than or equal to voltage amplitude threshold value, control device 3 controls the spike electricity that energy absorbing device 2 receives on cable
The energy of pressure.In another embodiment, control device 3 can become one with energy absorbing device 2.
Fig. 2 is that the structure of the system for eliminating variable-frequency motor peak voltage that the utility model one embodiment provides is shown
It is intended to.As in figure 2 it is shown, this system also includes energy conversion device 4, this energy conversion device 4 is with described energy absorbing device 2 even
Connect, be used for receiving the energy of the peak voltage that described energy absorbing device 2 is released, and the energy by described peak voltage is converted into
Heat energy.
This system also includes the control valve 5 being positioned between described energy absorbing device 2 and described energy conversion device 4.
Described control device 3 is also connected with described control valve 5, for receiving the energy datum that described energy absorbing device 2 sends,
Control described control valve 5 when described energy datum is more than or equal to energy datum threshold value to open.
The energy that energy absorbing device 2 absorbs peak voltage has certain restriction, and energy conversion device 4 can be by energy
The energy of the peak voltage that absorption plant 2 absorbs is converted into heat energy, thus ensures that energy absorbing device 2 can absorb more point
The energy of peak voltage.And can also have control valve 5 between energy absorbing device 2 and energy conversion device 4, at control valve 5
When opening, the energy of the peak voltage that energy absorbing device 2 absorbs just can be released to energy conversion device 4, thus is turned by energy
Gasifying device 4 is converted into heat energy.Control valve 5 can manual opening and closing, it is also possible to be connected with control device 3, and control device 3 connects in real time
Receive the energy datum energy value of the energy of peak voltage (i.e. in energy absorbing device 2) that energy absorbing device 2 sends, and judge
Whether energy datum is more than or equal to energy datum threshold value, when energy datum is more than or equal to energy datum threshold value, and control dress
Put 3 control control valves 5 to open, can be released when being full of energy absorbing device 2 with the energy ensureing peak voltage.
The system that the utility model provides can also include temperature detector 6, for detecting described energy conversion device 4
Temperature, and send temperature data;Described control device 3 is connected with described temperature detector 6 and described control valve 5, is used for connecing
Receiving described temperature data, when described temperature data is more than or equal to temperature threshold, described control device 3 controls described control valve
Door 5 is closed.
When the temperature of energy conversion device 4 is too high, electric energy should be avoided to the conversion further of heat energy.Therefore temperature detection
Device 6 detects the temperature of energy conversion device 4, and sends temperature data and receive temperature data to control device 3, control device 3, and
C.T data and temperature threshold, when temperature data is more than or equal to temperature threshold, control device 3 control control valve 5
Close, to lower the temperature to energy conversion device 4 regular hour.
The system that the utility model provides can also include current sinking device 7, installs on the cables., is used for absorbing
Shaft current.In one embodiment, described current sinking device 7 can become one with described energy absorbing device 2.
By technique scheme, use the system for eliminating variable-frequency motor peak voltage that the utility model provides,
This system includes detection device, energy absorbing device and control device.Detection device is utilized to detect the voltage amplitude on cable in real time
Degree, concurrent power transmission pressure amplitude degrees of data, utilize control device to receive the voltage amplitude data of self-test device, and will receive
Voltage amplitude data compare with voltage amplitude threshold value, when the voltage amplitude data receiving are more than or equal to voltage amplitude threshold
During value, the energy of the peak voltage on control device control energy absorbing device absorbing cable.What the utility model provided is used for
Eliminate variable-frequency motor peak voltage system price cheap, volume is little, stable performance, can protect motor bearings and to administer point
Peak voltage problem effect is notable.
Describe preferred embodiment of the present utility model above in association with accompanying drawing in detail, but, the utility model does not limit
Detail in above-mentioned embodiment, in technology concept of the present utility model, can be to skill of the present utility model
Art scheme carries out multiple simple variant, and these simple variant belong to protection domain of the present utility model.
It is further to note that each the concrete technical characteristic described in above-mentioned detailed description of the invention, at not lance
In the case of shield, can be combined by any suitable means, in order to avoid unnecessary repetition, the utility model is to respectively
Plant possible combination no longer to illustrate separately.
Additionally, also can be combined, as long as it is not disobeyed between various different embodiment of the present utility model
Carrying on the back thought of the present utility model, it should be considered as content disclosed in the utility model equally.