CN103916059B - Switched-reluctance-motor speed adjusting device - Google Patents
Switched-reluctance-motor speed adjusting device Download PDFInfo
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- CN103916059B CN103916059B CN201210592064.6A CN201210592064A CN103916059B CN 103916059 B CN103916059 B CN 103916059B CN 201210592064 A CN201210592064 A CN 201210592064A CN 103916059 B CN103916059 B CN 103916059B
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- 238000010586 diagram Methods 0.000 description 6
- 238000004146 energy storage Methods 0.000 description 3
- 230000001276 controlling effect Effects 0.000 description 2
- 230000005611 electricity Effects 0.000 description 2
- 238000005065 mining Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
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- 238000010248 power generation Methods 0.000 description 2
- 238000004804 winding Methods 0.000 description 2
- 230000007547 defect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
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Abstract
The invention relates to a switched-reluctance-motor speed adjusting device. The switched-reluctance-motor speed adjusting device includes a feedback unit or a rectifier bridge, an inversion unit, a braking unit, a power supplying unit, a power supply switching circuit and a transformer. A feedback unit power circuit is connected with a power grid through a feedback reactor or the rectifier bridge is directly connected with the power grid; the feedback unit power circuit or the rectifier bridge is connected with an inversion unit power circuit through positive and negative buses; a filtering capacitor is connected between the positive and negative busses in a bridging manner; a braking unit power circuit is connected in parallel with two ends of the filtering capacitor; the inversion unit is connected with a motor; the power supplying unit is connected with the braking unit; a control power supply of the feedback unit, a control power supply of the braking unit and a control power supply of the inversion unit are respectively connected to the transformer and the power supplying unit through the power supply switching circuit; and the transformer is connected to the power grid. With the switched-reluctance-motor speed adjusting device, problems which exists in power supplying of the control power supplies when a system performs braking working after the outage of the power grid can be solved; and the switched-reluctance-motor speed adjusting device only needs to be modified simply on the basis of the prior device so that cost is low and reliability is high.
Description
Technical Field
The invention relates to a speed regulating device of a switched reluctance motor, in particular to a speed regulating device of a switched reluctance motor, which can realize the control of power supply of a power supply when a system works in a braking mode after a power grid is cut off.
Background
Generally, the speed regulating device of the switched reluctance motor with the brake unit drives the switched reluctance motor to realize four-quadrant operation, and can realize braking deceleration stop in a power grid power-off state. A commonly used four-quadrant switch reluctance motor speed regulation device is shown in a structural diagram in figure 1, wherein a rectifier bridge is connected with an inverter unit power circuit through positive and negative buses, and a filter capacitor is connected between the positive and negative buses in a bridging mode. The rectifier bridge realizes the rectification of an alternating current power supply, and the inverter unit is connected with the motor to drive the SRM to run electrically or generate electricity; the brake unit can release the energy of the bus under the condition of the power generation operation of the motor or the power grid outage.
In order to realize the long-time power generation operation of the device and the function of power-off braking, an improved speed regulating device of the switched reluctance motor is provided afterwards, the structure diagram is shown in fig. 2, each unit power circuit is connected through a positive bus and a negative bus, and a filter capacitor is connected between the positive bus and the negative bus in a bridging mode. The feedback unit is connected with a power grid through a feedback reactor and has rectification and feedback functions; the inversion unit is connected with the motor and drives the motor SRM to electrically operate or generate electricity; the braking unit can release energy to the bus under the condition of grid outage or failure of the feedback unit. The speed regulating device is additionally provided with a brake unit on the basis of the speed regulating device shown in figure 1, and the speed regulating device is composed of a control power supply, a control circuit, a pushing circuit, a power circuit, a brake resistor and the like, so that the complexity of the system is increased, and the reliability is reduced.
In addition, the speed control devices shown in fig. 1 and 2 have the following disadvantages:
one, three units of control power supply can be taken from a direct current bus or an alternating current power supply, or an energy storage device, but all have limitations.
Secondly, because the mining belt or the lifting transportation system is generally a medium-voltage (660V-3300V) product, when a control power supply is taken from a direct-current bus, no existing product exists in the market of a medium-voltage DC/DC converter, customization and development are needed, and the difficulty in selecting the type of the device is high, and the reliability is low.
If the control power supply is taken from an alternating current power supply (a power supply different from the main loop), all or part of the power grid is powered off, the control power supply can also be powered off, and thus the power-off braking shutdown function cannot be realized; when the control power supply is taken from the energy storage device, the control power supply generally has two types of batteries and capacitors, and if energy storage devices such as storage batteries and the like are adopted, the requirements of national safety standards for mining can be met only by adopting an independent explosion-proof (intrinsic safety) structure, the technology is complex, and the realization difficulty is high; when the capacitor is used for storing energy, the quantity is too large, and the limited space is difficult to place.
Disclosure of Invention
In order to overcome the defects, the invention provides the speed regulating device of the switched reluctance motor, which can solve the problem of controlling the power supply of a power supply when a system works in a braking mode after a power grid is powered off, and is simple in modification on the basis of the conventional device, low in cost and high in reliability.
The invention provides a speed regulating device of a switched reluctance motor, which comprises: the brake system comprises a feedback unit or a rectifier bridge, an inverter unit and a brake unit, wherein the feedback unit comprises a feedback unit power circuit, the inverter unit comprises an inverter unit power circuit, the brake unit comprises a brake resistor and a brake unit power circuit, and the feedback unit, the inverter unit and the brake unit respectively comprise a control circuit, a control power supply and a push circuit; when the switched reluctance motor speed regulation device adopts the feedback unit, the switched reluctance motor speed regulation device also comprises a feedback reactor, a feedback unit power circuit is connected with a power grid through the feedback reactor, and the feedback unit power circuit is connected with an inversion unit power circuit through a positive bus and a negative bus; when the speed regulating device of the switched reluctance motor adopts a rectifier bridge, the rectifier bridge is directly connected with a power grid, and the rectifier bridge is connected with an inverter unit power circuit through positive and negative buses; a filter capacitor is connected between the positive bus and the negative bus in a bridging way; the brake unit power circuit is connected in parallel with two ends of the filter capacitor; the inversion unit is connected with the motor; wherein, this switched reluctance motor speed adjusting device still includes: the power supply unit, the power switching circuit and the transformer are connected; the power supply unit is connected with the braking unit; the control power supply of the feedback unit, the control power supply of the brake unit and the control power supply of the inversion unit are respectively connected to the transformer and the power supply unit through the power supply switching circuit; the transformer is connected with a power grid.
The brake unit power circuit is composed of an IGBT, one end of the brake unit power circuit is connected with a positive bus, and the other end of the brake unit power circuit is connected with a negative bus through a brake resistor.
The power supply unit comprises a power transformer, a rectifier diode and a filter capacitor, wherein the primary side of the power transformer is connected with a brake resistor, and the secondary side of the power transformer is connected with the diode in series and then connected with the capacitor in parallel.
The power supply switching circuit is composed of an analog control circuit or a digital control circuit and a contactor or a relay.
The digital control circuit is composed of one or more of a PLC, a singlechip, a DSP and an ARM.
The feedback reactor adopts a single inductor or a combination of an inductor and a capacitor.
According to the switched reluctance motor speed regulating device provided by the invention, the power supply switching circuit and the power supply unit connected to the brake unit are additionally arranged, after the power grid is cut off, the brake unit starts to work, the power transformer in the power supply unit changes the high voltage on the brake resistor in the brake unit into the low voltage, and after rectification, the power supply is supplied to the control power supply through the power supply switching circuit, so that the problem of power supply of the control power supply when the system is braked and works after the power grid is cut off is solved, and the switching reluctance motor speed regulating device is simple to modify on the basis of the conventional device, low in cost and high in.
Drawings
Fig. 1 is a schematic structural diagram of a conventional speed regulating device of a switched reluctance motor;
fig. 2 is a schematic structural diagram of another conventional speed regulating device for a switched reluctance motor;
FIG. 3 is a schematic structural diagram of a first embodiment of a speed adjusting device of a switched reluctance motor according to the present invention;
fig. 4 is a schematic structural diagram of a second embodiment of the speed adjusting device of the switched reluctance motor according to the present invention.
Detailed Description
The present invention will be described in detail below with reference to the accompanying drawings and examples.
As shown in fig. 3, a first embodiment of the speed adjusting device for a switched reluctance motor according to the present invention includes: the braking system comprises a rectifier bridge, an inverter unit, a braking unit, a power supply switching circuit and a transformer (shown as a transformer 1 in figure 4), wherein the feedback unit comprises a feedback unit power circuit, the inverter unit comprises an inverter unit power circuit, the braking unit comprises a braking resistor and a braking unit power circuit, and the feedback unit, the inverter unit and the braking unit respectively comprise a control circuit, a control power supply and a pushing circuit. The connection relationship of each circuit, module and unit in this embodiment is as follows: the rectifier bridge is connected with the inverter unit power circuit through a positive bus and a negative bus; a filter capacitor C is connected between the positive bus and the negative bus in a crossing manner; the brake unit power circuit is connected in parallel with two ends of the filter capacitor C; the inversion unit is connected with the motor SRM; the power supply unit is connected with the braking unit; the control power supply of the feedback unit, the control power supply of the brake unit and the control power supply of the inversion unit are respectively connected to the transformer 1 and the power supply unit through the power supply switching circuit; the transformer 1 is connected to the grid.
As shown in fig. 4, a second embodiment of the speed adjusting device for a switched reluctance motor according to the present invention includes: the system comprises a feedback reactor, a feedback unit, an inversion unit, a brake unit, a power supply switching circuit and a transformer (shown as a transformer 1 in figure 3); the feedback unit comprises a feedback unit power circuit, the inversion unit comprises an inversion unit power circuit, the brake unit comprises a brake resistor and a brake unit power circuit, and the feedback unit, the inversion unit and the brake unit respectively comprise a control circuit, a control power supply and a pushing circuit. The connection relationship of each circuit, module and unit in this embodiment is as follows: the feedback unit power circuit is connected with the power grids L1, L2 and L3 through a feedback reactor, and the feedback unit power circuit is connected with the inverter unit power circuit through a positive bus and a negative bus; a filter capacitor C is connected between the positive bus and the negative bus in a crossing manner; the brake unit power circuit is connected in parallel with two ends of the filter capacitor C; the inversion unit is connected with the motor SRM; the power supply unit is connected with the braking unit; the control power supply of the feedback unit, the control power supply of the brake unit and the control power supply of the inversion unit are respectively connected to the transformer 1 and the power supply unit through the power supply switching circuit; the transformer 1 is connected to the grid.
The composition and the working principle of each unit are explained in detail as follows:
the braking unit is composed of a braking resistor, a braking unit power circuit, a pushing circuit and a control circuit, wherein the braking unit power circuit is composed of an IGBT, one end of the braking unit power circuit is connected with a positive bus, and the other end of the braking unit power circuit is connected with a negative bus through the braking resistor. When a control circuit of the braking unit detects that the voltage of the bus rises and the power supply is cut off or the feedback unit fails, a PWM (pulse width modulation) chopping control signal is generated to drive the IGBT to be switched on and off, and redundant energy on the bus is consumed on the braking resistor. The feedback reactor plays a role in reducing harmonic waves when being powered on, and filters feedback current when braking.
The inversion unit consists of an inversion unit power circuit, a pushing circuit, a control circuit and a control power supply, and the inversion unit power circuit can be of a single-phase or multi-phase structure according to the type of the driving switched reluctance motor. When the motor runs electrically, a control circuit of the inverter unit generates an electric control signal by detecting the relative position of a stator and a rotor of the switched reluctance motor, a power circuit is driven by a push circuit to supply power to a motor winding in an inductance rising interval of the motor, and electric energy is converted into mechanical energy; when the motor is braked and operated, a control circuit of the inverter unit generates a brake control signal by detecting the relative position of a stator and a rotor of the switched reluctance motor, a power circuit is driven to excite a motor winding by a pushing circuit in a motor inductance reduction interval, mechanical energy is converted into electric energy, and the inverter unit converts the power generated by the motor into direct current electric energy to charge a direct current bus.
The feedback unit consists of a feedback unit power circuit, a pushing circuit, a control circuit and a control power supply, wherein the feedback unit power circuit adopts IGBT to form a bridge structure, and can be single-phase or multi-phase according to the type of the connected power supply. When the motor runs electrically, the diode connected in parallel with the IGBT plays a role of a rectifier bridge; when the brake is operated, the control circuit detects that the voltage of the bus rises, sends a feedback drive signal, drives the power circuit to work after being converted by the push circuit, and inverts the direct current on the bus into alternating current to flow back to the feed network according to the phase sequence of the voltage of the incoming alternating current network.
The power supply unit comprises a power transformer (shown as a power transformer T1 in fig. 3 and 4), a rectifier diode D1 and a filter capacitor C1, wherein the primary side of the power transformer T1 is connected with a braking resistor, and the secondary side of the power transformer T1 is connected with a diode D1 in series and then is connected with a capacitor C1 in parallel. The power supply unit can step down, rectify and filter the voltage on the brake resistor and is connected to the power supply switching circuit.
The power supply switching circuit is composed of an analog control circuit or a digital control circuit and a contactor, and the contactor can be replaced by a relay.
If the power supply switching circuit adopts a digital control circuit, the digital control circuit can be formed by one or a plurality of combinations of a PLC, a singlechip, a DSP and an ARM.
The feedback reactor adopts a single inductor or a combination of an inductor and a capacitor.
The working process of the matching of the power supply switching circuit and the power supply unit is as follows:
when the power grid is normal, the power supplies of the control circuit and the power circuit of each unit are both provided by the power grid, and the voltage of the power grid is reduced by the transformer 1 and then is sent into the power switching circuit to supply power to the control power supply; when the power grid is suddenly cut off, the brake unit starts to work, the power supply switching circuit connects the power supply unit to the control power supply of each unit, and at the moment, the control power supply is supplied by the power supply unit.
According to the invention, by adding the power supply switching circuit and the power supply unit connected to the braking unit, after the power grid is cut off, the braking unit starts to work, the transformer in the power supply unit changes the high voltage on the braking resistor in the braking unit into low voltage, and after rectification, the power supply switching circuit supplies power to the control power supply, so that the problem of controlling the power supply when the system is braked and works after the power grid is cut off is solved, and the power supply switching circuit is only required to be simply modified on the basis of the existing device, so that the cost is low, and the reliability is high.
Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.
Claims (4)
1. A switched reluctance machine speed adjustment apparatus comprising: the brake system comprises a feedback unit or a rectifier bridge, an inverter unit and a brake unit, wherein the feedback unit comprises a feedback unit power circuit, the inverter unit comprises an inverter unit power circuit, the brake unit comprises a brake resistor and a brake unit power circuit, and the feedback unit, the inverter unit and the brake unit respectively comprise a control circuit, a control power supply and a push circuit;
when the switched reluctance motor speed regulation device adopts the feedback unit, the switched reluctance motor speed regulation device also comprises a feedback reactor, a feedback unit power circuit is connected with a power grid through the feedback reactor, and the feedback unit power circuit is connected with an inversion unit power circuit through a positive bus and a negative bus;
when the speed regulating device of the switched reluctance motor adopts a rectifier bridge, the rectifier bridge is directly connected with a power grid, and the rectifier bridge is connected with an inverter unit power circuit through positive and negative buses;
a filter capacitor is connected between the positive bus and the negative bus in a bridging way;
the brake unit power circuit is connected in parallel with two ends of the filter capacitor;
the inversion unit is connected with the motor;
the switched reluctance motor speed adjusting device is characterized by further comprising: the power supply unit, the power switching circuit and the transformer are connected; the power supply unit is connected with the braking unit; the control power supply of the feedback unit, the control power supply of the brake unit and the control power supply of the inversion unit are respectively connected to the transformer and the power supply unit through the power supply switching circuit; the transformer is connected with a power grid; wherein,
the brake unit power circuit is formed by an IGBT, one end of the brake unit power circuit is connected with a positive bus, and the other end of the brake unit power circuit is connected with a negative bus through a brake resistor;
the power supply unit comprises a power transformer, a rectifier diode and a filter capacitor, wherein the primary side of the power transformer is connected with a brake resistor, and the secondary side of the transformer is connected with the diode in series and then connected with the capacitor in parallel;
after the power grid is cut off, a power transformer in the power supply unit changes high voltage on a brake resistor in the brake unit into low voltage, and after rectification, the power supply is supplied to the control power supply through the power supply switching circuit.
2. The switched reluctance motor speed regulating device according to claim 1, wherein the power switching circuit is formed by an analog control circuit or a digital control circuit and a contactor or a relay.
3. The switched reluctance motor speed regulating device of claim 2, wherein the digital control circuit is composed of one or more of a PLC, a single chip microcomputer, a DSP, and an ARM.
4. The switched reluctance motor speed regulating device according to claim 1, wherein the feedback reactor uses a single inductor or a combination of an inductor and a capacitor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210592064.6A CN103916059B (en) | 2012-12-28 | 2012-12-28 | Switched-reluctance-motor speed adjusting device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210592064.6A CN103916059B (en) | 2012-12-28 | 2012-12-28 | Switched-reluctance-motor speed adjusting device |
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| Publication Number | Publication Date |
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| CN103916059A CN103916059A (en) | 2014-07-09 |
| CN103916059B true CN103916059B (en) | 2017-02-22 |
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| CN201210592064.6A Expired - Fee Related CN103916059B (en) | 2012-12-28 | 2012-12-28 | Switched-reluctance-motor speed adjusting device |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN106301000B (en) * | 2016-08-11 | 2018-11-23 | 珠海格力电器股份有限公司 | converter and control unit thereof |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1679224A (en) * | 2002-08-30 | 2005-10-05 | 三垦电气株式会社 | Switching power source device |
| CN2802842Y (en) * | 2005-05-31 | 2006-08-02 | 北京中纺锐力机电有限公司 | Power-off brake controller of speed regulating system of switch reluctance motor |
| CN101286726A (en) * | 2008-06-12 | 2008-10-15 | 杭州西子孚信科技有限公司 | Driving device for electric machine and control method for driving motor |
| CN202334435U (en) * | 2011-11-16 | 2012-07-11 | 北京中纺锐力机电有限公司 | Novel switched reluctance motor speed adjusting device |
| CN202978794U (en) * | 2012-12-28 | 2013-06-05 | 北京中纺锐力机电有限公司 | Switched reluctance motor speed adjusting device |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5789952B2 (en) * | 2010-10-21 | 2015-10-07 | 株式会社デンソー | Motor control device |
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- 2012-12-28 CN CN201210592064.6A patent/CN103916059B/en not_active Expired - Fee Related
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1679224A (en) * | 2002-08-30 | 2005-10-05 | 三垦电气株式会社 | Switching power source device |
| CN2802842Y (en) * | 2005-05-31 | 2006-08-02 | 北京中纺锐力机电有限公司 | Power-off brake controller of speed regulating system of switch reluctance motor |
| CN101286726A (en) * | 2008-06-12 | 2008-10-15 | 杭州西子孚信科技有限公司 | Driving device for electric machine and control method for driving motor |
| CN202334435U (en) * | 2011-11-16 | 2012-07-11 | 北京中纺锐力机电有限公司 | Novel switched reluctance motor speed adjusting device |
| CN202978794U (en) * | 2012-12-28 | 2013-06-05 | 北京中纺锐力机电有限公司 | Switched reluctance motor speed adjusting device |
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Owner name: NIDEC (BEIJING) DRIVE SYSTEM TECHNIQUE CO., LTD. Free format text: FORMER OWNER: BEIJING CHINA TEX MECHANICAL + ELECTRICAL ENGINEERING LTD. Effective date: 20150703 |
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Effective date of registration: 20150703 Address after: 101102 Beijing, Tongzhou District Sheng King South Street, No. 13, No. 101, 201-1, 301, 15, Applicant after: Nidec (Beijing) Transmission Technology Co.,Ltd. Address before: 101102, Beijing, Zhongguancun science and Technology Park, Jinqiao Science and technology industrial base, 15 South four street, 16A, Tongzhou District Applicant before: Beijing China Tex Mechanical & Electrical Engineering Ltd. |
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