CN215681909U - Control device for double-bus double-frequency-converter double-motor dragging - Google Patents
Control device for double-bus double-frequency-converter double-motor dragging Download PDFInfo
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- CN215681909U CN215681909U CN202121479624.8U CN202121479624U CN215681909U CN 215681909 U CN215681909 U CN 215681909U CN 202121479624 U CN202121479624 U CN 202121479624U CN 215681909 U CN215681909 U CN 215681909U
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Abstract
The utility model relates to the technical field of electric dragging and discloses a control device for double-bus double-frequency-converter double-motor dragging, which comprises two groups of buses, two frequency converters, two motors, a plurality of contactors and isolating switches, wherein the two groups of buses are connected with the two frequency converters; the two motors are connected with the corresponding high-voltage buses through contactors; the motor is connected with the frequency converter through an isolating switch and a contactor; the frequency converter is connected with the bus through an isolating switch and a contactor; the contactor is controlled by a frequency converter control cabinet; and the electromagnetic lock of the isolating switch is electrically locked by the frequency converter. When each isolating switch is operated, the isolating switch can be operated without a main power supply, so that the personal safety is ensured; when any frequency converter or motor breaks down and exits, the upper-level isolating switch of the loop where the frequency converter or the motor is located can be disconnected, an obvious breakpoint is formed, the requirements of safety regulations are met, the use safety is improved, the high-speed frequency converter or the motor has excellent technical reliability, and the popularization is facilitated.
Description
Technical Field
The utility model relates to the technical field of electric dragging, in particular to a control device for double-motor dragging of a double-bus double-frequency converter.
Background
At present, a frequency converter is widely applied to the field of electric dragging, the frequency converter drags a motor, the motor drives a load to run, the advantages of soft start, starting current limitation, energy conservation and speed regulation are achieved, and the dragging mode comprises a one-dragging-one mode, a one-dragging-two mode and the like. At present, a plurality of enterprises start to use a one-use-one-standby mode for some more important loads, and once the equipment fails, the equipment has great influence on production, so that serious economic loss and even harm to personal safety are caused. A set of standby machines is configured, and once one set of equipment fails, the standby machines can be rapidly switched to operate. Meanwhile, manufacturers often configure a standby frequency converter for the standby motor, and when the two frequency converters and the two motors are not in fault, the two frequency converters are used for dragging the motors in a one-to-one mode, so that the two motors operate in turn.
According to the prior art, the frequency converter is connected with the motor by using the contactor, when the frequency converter or the motor breaks down, the frequency converter or the motor needs to be withdrawn for maintenance, and the requirement of obvious breakpoints in safety regulations is not met if only the contactor is connected.
On the other hand, for important load equipment, the buses are required to be reserved so that when one of the power supplies fails, the buses can be quickly switched to the standby power supply without damaging the property of an enterprise.
SUMMERY OF THE UTILITY MODEL
In view of the above problems in the prior art, the present invention provides a control device for dual motor drive of a dual bus dual frequency converter.
In order to achieve the purpose, the utility model provides a control device for double-bus double-frequency converter double-motor dragging, which comprises two groups of buses, two frequency converters, two motors, a plurality of contactors and an isolating switch;
the two motors are connected with the corresponding high-voltage buses through contactors;
the motor is connected with the frequency converter through an isolating switch and a contactor;
the frequency converter is connected with the bus through an isolating switch and a contactor;
the contactor is controlled by a frequency converter control cabinet;
the electromagnetic lock of the isolating switch is electrically locked by a frequency converter;
the bus comprises a bus 1 and a bus 2, the frequency converter comprises a frequency converter 1 and a frequency converter 2, the motor comprises a motor M1 and a motor M2, the contactor comprises KM11, KM13, KM14, KM21, KM23 and KM24, and the isolating switch comprises QS11, QS12, QS13, QS21, QS22, QS23, QS0 and QS 10;
the bus 1 is connected with a motor M1 through a contactor KM14, the bus 1 is connected with the input end of the frequency converter 1 through a contactor KM11 and an isolating switch QS11, and the output end of the frequency converter 1 is connected with a motor M1 through isolating switches QS12, QS13 and a contactor KM 13;
the bus 2 is connected with a motor M2 through a contactor KM24, the bus 2 is connected with the input end of the frequency converter 2 through a contactor KM21 and an isolating switch QS21, and the output end of the frequency converter 2 is connected with a motor M2 through isolating switches QS22, QS23 and a contactor KM 23;
the bus 1 is connected with the input end of the frequency converter 2 through a contactor KM11 and isolating switches QS0 and QS 21;
the bus 2 is connected with the input end of the frequency converter 1 through a contactor KM21 and isolating switches QS0 and QS 11;
the output end of the frequency converter 1 is connected with a motor M2 through isolating switches QS12, QS10, QS23 and a contactor KM 23;
the output end of the frequency converter 2 is connected with a motor M1 through isolating switches QS22, QS10, QS13 and a contactor KM 13.
Preferably, the contactor is replaced by a circuit breaker.
Compared with the prior art, the control device for double-motor dragging of the double-bus double-frequency converter has the following beneficial effects:
the utility model is suitable for the occasions that two groups of buses are mutually standby, two frequency converters are mutually standby and two motors are mutually standby, and can realize the one-to-one frequency conversion dragging of the frequency converter 1 to the motor M1 and the frequency converter 2 to the motor M2, and also can realize the frequency conversion operation of any one motor dragged by the other frequency converter after one frequency converter fails; the two groups of buses can realize that the bus 1 is connected with the frequency converter 1, and the bus 2 is connected with the frequency converter 2, and can also realize that when one group of buses fails, the other group of buses is connected with any frequency converter at will; when the two frequency converters are in failure, the two motors can be put into power frequency operation, the production stop risk caused by equipment failure is reduced to the maximum extent, and the utilization rate of the equipment is greatly improved;
each isolating switch can be operated without a main power supply, personal safety is guaranteed, when any frequency converter or motor breaks down and exits, the upper isolating switch of the loop where the frequency converter or the motor is located can be disconnected, obvious breakpoints are formed, the requirements of safety regulations are met, use safety is improved, and the isolating switch has superior technical reliability and is beneficial to popularization.
Drawings
FIG. 1 is a schematic diagram of a control main loop of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present disclosure more clear, the technical solutions of the embodiments of the present disclosure will be described below clearly and completely with reference to the accompanying drawings of the embodiments of the present disclosure.
The structures, proportions, sizes, and other dimensions shown in the drawings and described in the specification are for understanding and reading the present disclosure, and are not intended to limit the scope of the present disclosure, which is defined in the claims, and are not essential to the art, and any structural modifications, changes in proportions, or adjustments in size, which do not affect the efficacy and attainment of the same are intended to fall within the scope of the present disclosure. In addition, the terms such as "upper", "lower", "left", "right" and "middle" used in the present specification are for clarity of description, and are not intended to limit the scope of the present invention, and changes or modifications of the relative relationship may be made without substantial technical changes.
Referring to fig. 1, a control device for dual-bus dual-frequency converter dual-motor dragging includes two groups of buses, two frequency converters, two motors, a plurality of contactors, and an isolating switch;
the two motors are connected with the corresponding high-voltage buses through contactors;
the motor is connected with the frequency converter through an isolating switch and a contactor;
the frequency converter is connected with the bus through an isolating switch and a contactor;
the contactor is controlled by a frequency converter control cabinet;
the electromagnetic lock of the isolating switch is electrically locked by a frequency converter;
the bus comprises a bus 1 and a bus 2, the frequency converter comprises a frequency converter 1 and a frequency converter 2, the motor comprises a motor M1 and a motor M2, the contactor comprises KM11, KM13, KM14, KM21, KM23 and KM24, and the isolating switch comprises QS11, QS12, QS13, QS21, QS22, QS23, QS0 and QS 10;
the bus 1 is connected with a motor M1 through a contactor KM14, the bus 1 is connected with the input end of the frequency converter 1 through a contactor KM11 and an isolating switch QS11, and the output end of the frequency converter 1 is connected with a motor M1 through isolating switches QS12, QS13 and a contactor KM 13;
the bus 2 is connected with a motor M2 through a contactor KM24, the bus 2 is connected with the input end of the frequency converter 2 through a contactor KM21 and an isolating switch QS21, and the output end of the frequency converter 2 is connected with a motor M2 through isolating switches QS22, QS23 and a contactor KM 23;
the bus 1 is connected with the input end of the frequency converter 2 through a contactor KM11 and isolating switches QS0 and QS 21;
the bus 2 is connected with the input end of the frequency converter 1 through a contactor KM21 and isolating switches QS0 and QS 11;
the output end of the frequency converter 1 is connected with a motor M2 through isolating switches QS12, QS10, QS23 and a contactor KM 23;
the output end of the frequency converter 2 is connected with a motor M1 through isolating switches QS22, QS10, QS13 and a contactor KM 13.
The contactor is replaced by a breaker.
The device has the following operation modes:
mode 1: the bus 1 is connected with the input end of the frequency converter 1 through a contactor KM11 and an isolating switch QS11, and the output end of the frequency converter 1 is connected with the motor M1 through isolating switches QS12, QS13 and a contactor KM 13; the bus 2 is connected with the input end of the frequency converter 2 through a contactor KM21 and an isolating switch QS21, and the output end of the frequency converter 2 is connected with the motor M2 through isolating switches QS22, QS23 and a contactor KM 23.
Mode 2: the bus 1 is connected with the input end of the frequency converter 2 through a contactor KM11 and isolating switches QS0 and QS21, and the output end of the frequency converter 2 is connected with a dragging motor M1 through isolating switches QS22, QS10, QS13 and a contactor KM 13.
Mode 3: the bus 2 is connected with the input end of the frequency converter 1 through a contactor KM21 and isolating switches QS0 and QS11, and the output end of the frequency converter 1 is connected with a dragging motor M2 through isolating switches QS12, QS10, QS23 and a contactor KM 23.
Mode 4: the bus 2 is connected with the input end of the frequency converter 1 through a contactor KM21 and isolation switches QS0 and QS11, and the output of the frequency converter 1 is connected with the motor M1 through the isolation switches QS12 and QS13 and a contactor KM 13.
Mode 5: the bus 1 is connected with the input of the frequency converter 2 through a contactor KM11 and isolation switches QS0 and QS21, and the output of the frequency converter 2 is connected with a motor M2 through the isolation switches QS22 and QS23 and a contactor KM 23.
Mode 6: the bus 2 is connected with the input of the frequency converter 2 through a contactor KM21 and an isolating switch QS21, and the output of the frequency converter 2 is connected with a motor M1 through isolating switches QS22, QS10, QS13 and a contactor KM 13.
Mode 7: the bus 1 is connected with the input of the frequency converter 1 through a contactor KM11 and an isolating switch QS11, and the output of the frequency converter 1 is connected with a motor M2 through isolating switches QS12, QS10, QS23 and a contactor KM 23.
Mode 8: the bus 1 is connected with a motor M1 through a contactor KM 14.
Mode 9: the bus 2 is connected with a motor M2 through a contactor KM 24.
Under the normal condition, two sets of generating lines, two converters, two motors all do not have the trouble, and the operation of using mode 1 mode:
step 1-1, enabling isolating switches QS10 and QS0 to be in an opening state, operating the isolating switches QS11, QS12 and QS13 to be closed, and operating the isolating switches QS21, QS22 and QS23 to be closed;
step 1-2, supplying power to a bus 1, switching on a frequency converter 1 to automatically control contactors KM11 and KM13, supplying power to a bus 2, and switching on frequency converter 2 to automatically control contactors KM21 and KM 23;
and 1-3, sending a starting signal to the frequency converter 1, starting the frequency converter 1 to drive the motor M1 to operate, sending a starting signal to the frequency converter 2, and starting the frequency converter 2 to drive the motor M2 to operate.
If only one motor is needed to operate in a variable frequency mode, only the corresponding motor loop is operated, and in addition, the main loop isolating switch and the contactor which are not needed can not be switched on.
If the frequency converter 1 has a fault, the frequency converter 2 does not have a fault, the modes 8, 9 and 2 can be used for operation, and if the frequency converter 2 has a fault, the frequency converter 1 does not have a fault, the modes 8, 9 and 3 are used for operation.
Taking the frequency converter 1 as an example, the switching process of the device between the modes when only 1 frequency converter fails will be described in detail.
When the frequency converter 1 fails during operation, the frequency converter 1 will automatically switch the motor M1 to the mode 8 operation mode:
step 2: the frequency converter 1 automatically controls the contactors KM11 and KM13 to open and then automatically controls the contactor KM14 to close, so that the motor M1 is converted into a power frequency running state of a mode 8.
At the moment, the upper and lower ports of the isolating switches QS11 and QS12 are in a power-off state, the isolating switches can be switched off by manual operation, the input and the output of the frequency converter 1 have obvious breakpoints, and the frequency converter 1 can be overhauled and maintained.
During the maintenance of the frequency converter 1, if the power frequency operation of the motor M1 is stopped in the middle, the motor M1 needs to operate again, if the frequency converter 2 is in an operating state, the motor M2 can be switched to a power frequency operating state of a mode 9, and then the mode 2 mode is used for starting the motor M1, so that the motor M1 is enabled to realize soft start.
Step 3-1: converting a working frequency signal to the frequency converter 2, and automatically increasing the output frequency to 50Hz by the frequency converter 2;
step 3-2: then, the frequency, the phase and the amplitude of a power frequency power grid are detected, the output of the frequency converter 2 is adjusted to be in the same frequency and phase as the power frequency, the contactor KM24 is automatically controlled to be switched on, then the contactors KM21 and KM23 are automatically switched off, and the motor M2 is switched to a power frequency running state of a mode 9;
step 3-3: at the moment, the upper and lower ports of an isolating switch QS23 are in a power-off state, and the isolating switch is switched off by manual operation;
step 3-4: at the moment, the isolating switches QS11 and QS12 are both in an open state, and the isolating switches QS0 and QS10 are switched on;
step 3-5: at the moment, the isolating switches QS0, QS21, QS22, QS10 and QS13 are in a closing state, the bus 1 is powered on, and the frequency converter 2 automatically controls the contactor KM11 and the contactor KM13 to be closed;
step 3-6: giving a starting signal to the frequency converter 2, and driving the motor M1 to operate in a frequency conversion mode by the frequency converter 2;
at this time, the frequency converter 2 can continue to drag the motor M1 to perform frequency conversion operation, if the motor M1 needs to be converted to power frequency operation, a power frequency signal can be converted to the frequency converter 2, the frequency converter 2 automatically raises the output frequency to 50Hz, the output of the frequency converter 2 is adjusted to be in the same frequency and phase with the power frequency by detecting the frequency, phase and amplitude of a power frequency power grid, the contactor KM14 is automatically controlled to be switched on, the contactors KM11 and KM13 are automatically switched off, the motor M1 is converted to a power frequency operation mode 8, and the frequency converter 2 exits from operation;
if the motor M2 needs to be converted into a frequency conversion operation state, the frequency converter 2 can be put into the main loop of the motor M2;
step 3-7: manually switching off isolating switches QS13, QS0 and QS10, and switching on an isolating switch QS 23;
step 3-8: at this time, a frequency conversion signal is sent to the frequency converter 2, the frequency converter 2 controls the contactor KM21 and the contactor KM23 to be switched on, the frequency, the phase and the amplitude of the motor M2 are automatically detected, the frequency converter 2 directly outputs a corresponding voltage vector to the motor M2, then the power frequency contactor KM24 is automatically switched off, and the motor M2 is converted into a frequency conversion operation mode.
The above is a description of the switching process in which the frequency converter 1 fails and the frequency converter 2 does not fail, and if the frequency converter 2 fails, the switching process is similar and will not be described again.
The operation mode when only 1 frequency converter in the device has a fault is described above, the operation mode when the bus has a fault is described below, if the bus 1 has a fault, the operation mode of the mode 4 or the mode 6 can be used to start the motor M1, if the bus 2 has a fault, the operation mode of the mode 5 or the mode 7 can be used to start the motor M2, and the specific conversion process is described below by taking the bus 1 having a fault as an example.
Step 4-1: if the frequency converter 2 is in a frequency conversion running state and drags the motor M2, a power frequency signal is transmitted to the frequency converter 2, the output frequency of the frequency converter 2 is increased to 50Hz, then the frequency, the phase and the amplitude of a power frequency power grid are detected, the output of the frequency converter 2 is adjusted to be in the same frequency and phase with the power frequency, the contactor KM24 is automatically controlled to be switched on, the contactors KM21 and KM23 are automatically switched off, and the motor M2 is converted to the power frequency running state of the mode 9;
if inverter 2 is selected to start motor M1, mode 6 will be used;
step 4-2: manually operating an isolating switch QS23 to switch off, operating an isolating switch QS12 to switch off, then operating an isolating switch QS10 to switch on, and ensuring that the isolating switch QS13 is in a switch-on state and the QS0 is in a switch-off state at the moment;
step 4-3: the frequency converter 2 automatically controls the contactors KM21 and KM13 to be switched on, a starting signal is given to the frequency converter 2, and the frequency converter 2 enables the motor M1 to realize soft start in a mode 6 mode;
if inverter 1 is selected to start motor M1, mode 4 will be used;
step 4-4: manually operating an isolating switch QS21 to switch off, operating an isolating switch QS0 to switch on, and ensuring that the isolating switch QS11, the isolating switch QS12 and the isolating switch QS13 are in a switch-on state and the isolating switch QS10 is in a switch-off state at the moment;
and 4-5: the frequency converter 1 automatically controls the contactors KM21 and KM13 to be switched on, a starting signal is given to the frequency converter 1, and the frequency converter 1 enables the motor M1 to realize soft start in a mode 4 mode;
the above is the operation mode when the bus 1 has a fault and the bus 2 has no fault, if the bus 2 has a fault and the bus 1 has no fault, the operation method is similar, and the operation is performed in the mode 7 or the mode 5, which is not described again.
The utility model is suitable for the occasions that two groups of buses are mutually standby, two frequency converters are mutually standby and two motors are mutually standby, and can realize the one-to-one frequency conversion dragging of the frequency converter 1 to the motor M1 and the frequency converter 2 to the motor M2, and also can realize the frequency conversion operation of any one motor dragged by the other frequency converter after one frequency converter fails; the two groups of buses can realize that the bus 1 is connected with the frequency converter 1, and the bus 2 is connected with the frequency converter 2, and can also realize that when one group of buses fails, the other group of buses is connected with any frequency converter at will; when the two frequency converters are in failure, the two motors can be put into power frequency operation, the production stop risk caused by equipment failure is reduced to the maximum extent, and the utilization rate of the equipment is greatly improved;
each isolating switch can be operated without a main power supply, personal safety is guaranteed, when any frequency converter or motor breaks down and exits, the upper isolating switch of the loop in which the frequency converter or the motor is positioned can be disconnected, obvious breakpoints are formed, the requirements of safety regulations are met, use safety is improved, and the isolating switch has superior technical reliability, is beneficial to popularization
The above description is only an exemplary embodiment of the present invention, and is not intended to limit the present invention, the scope of which is defined by the claims. Various modifications and equivalents may be made by those skilled in the art within the spirit and scope of the present invention, and such modifications and equivalents should also be considered as falling within the scope of the present invention.
Claims (2)
1. A control device for double-bus double-frequency converter double-motor dragging is characterized by comprising two groups of buses, two frequency converters, two motors, a plurality of contactors and isolating switches;
the two motors are connected with the corresponding high-voltage buses through contactors;
the motor is connected with the frequency converter through an isolating switch and a contactor;
the frequency converter is connected with the bus through an isolating switch and a contactor;
the contactor is controlled by a frequency converter control cabinet;
the electromagnetic lock of the isolating switch is electrically locked by a frequency converter;
the bus comprises a bus 1 and a bus 2, the frequency converter comprises a frequency converter 1 and a frequency converter 2, the motor comprises a motor M1 and a motor M2, the contactor comprises KM11, KM13, KM14, KM21, KM23 and KM24, and the isolating switch comprises QS11, QS12, QS13, QS21, QS22, QS23, QS0 and QS 10;
the bus 1 is connected with a motor M1 through a contactor KM14, the bus 1 is connected with the input end of the frequency converter 1 through a contactor KM11 and an isolating switch QS11, and the output end of the frequency converter 1 is connected with a motor M1 through isolating switches QS12, QS13 and a contactor KM 13;
the bus 2 is connected with a motor M2 through a contactor KM24, the bus 2 is connected with the input end of the frequency converter 2 through a contactor KM21 and an isolating switch QS21, and the output end of the frequency converter 2 is connected with a motor M2 through isolating switches QS22, QS23 and a contactor KM 23;
the bus 1 is connected with the input end of the frequency converter 2 through a contactor KM11 and isolating switches QS0 and QS 21;
the bus 2 is connected with the input end of the frequency converter 1 through a contactor KM21 and isolating switches QS0 and QS 11;
the output end of the frequency converter 1 is connected with a motor M2 through isolating switches QS12, QS10, QS23 and a contactor KM 23;
the output end of the frequency converter 2 is connected with a motor M1 through isolating switches QS22, QS10, QS13 and a contactor KM 13.
2. The control device for double-bus double-frequency converter double-motor dragging according to claim 1, wherein the contactor is replaced by a circuit breaker.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121479624.8U CN215681909U (en) | 2021-06-30 | 2021-06-30 | Control device for double-bus double-frequency-converter double-motor dragging |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202121479624.8U CN215681909U (en) | 2021-06-30 | 2021-06-30 | Control device for double-bus double-frequency-converter double-motor dragging |
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| Publication Number | Publication Date |
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| CN215681909U true CN215681909U (en) | 2022-01-28 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202121479624.8U Active CN215681909U (en) | 2021-06-30 | 2021-06-30 | Control device for double-bus double-frequency-converter double-motor dragging |
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| CN (1) | CN215681909U (en) |
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- 2021-06-30 CN CN202121479624.8U patent/CN215681909U/en active Active
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