CN101478284B

CN101478284B - Motor system capable of lowering common mode noise

Info

Publication number: CN101478284B
Application number: CN2008100000171A
Authority: CN
Inventors: 李寿民
Original assignee: Delta Optoelectronics Inc
Current assignee: Delta Electronics Inc; Delta Optoelectronics Inc
Priority date: 2008-01-02
Filing date: 2008-01-02
Publication date: 2011-06-15
Anticipated expiration: 2028-01-02
Also published as: CN101478284A

Abstract

The invention provides a motor system that can reduce common mode noise. The motor system comprises an AC power supply, a first transformer unit and a second transformer unit, wherein, the first transformer unit and the second transformer unit are connected with the AC power supply and can provide DC voltage; and the DC voltage of the first transformer unit and the DC voltage of the second transformer unit respectively supply a drive part and a control part of the motor system, thereby reducing the common mode noise coupling to a control power supply winding through a transformer winding at the drive part. Furthermore, stopping signals can close a pulse-width modulation integrated circuit of the power supply through an optical coupler or a relay, thereby leading the first transformer unit not to output power to the drive part of the motor so as to achieve the safe shutdown requirement.

Description

Can reduce the motor system of common-mode noise

Technical field

The present invention relates to a kind of motor system, especially a kind of motor system that reduces common-mode noise and reach safe shutdown.

Background technology

Referring to Fig. 1, be the power supply supply schematic diagram of known motor-driven system.Exchange (AC) power supply 40 through a transformer unit 42 voltage transformation of (comprising rectifying part and DC-DC conversion part) after, can supply direct voltage and drive the power supply 44 of frequency converter and control section for igbt (IGBT).

Specifically, referring to Fig. 2, for the block diagram of safety function operation is provided in known motor driven and the control system.The direct voltage 44A that 42 conversions are provided through transformer unit supplies power to the control section that comprises microcontroller 50, application-specific integrated circuit (ASIC) (ASIC) 52 and interface unit 54.Moreover, even the direct voltage 44A that these transformer unit 42 conversions are provided is fed to optical coupling switch element 56 and power cell 58.This optical coupling switch element 56 can be subjected to the control of this microcontroller 50 and closes or be open at gate switch (not shown) in the power cell 58.Moreover for security mechanism, stopping signal 64 can be controlled electromagnetic switch 62, to cut off the electric power for motor 60.

Yet in the circuit of Figure 1 and Figure 2, has following point:, can't make control chip obtain clean feedback signal (feedback signal) effectively because motor drive circuit uses single transformer to be supplied to power cell 58 and control chip (dotted portion that comprises microcontroller 50, ASIC 52 and interface unit 54) accessory power supply.Two kinds of power supplys (driving power+control power supply) are shared single transformer 42, its control power supply can be activated power supply noise via transformer coupled to the influence of controlling power supply.In other words, the power supply winding is coupled to control power supply winding with common-mode noise and can causes the control board noise very big.

Moreover (electromagnetic switch W) (not shown, as to be included in the power cell 58) is quite heavy and life problems is arranged, and needs periodic maintenance for U, V to be used in output at present.Stopping signal 64 must could be cut off electric power for motor 60 via electromagnetic switch 62, reaches demand for security, yet causes the circuit complicated problems.

Summary of the invention

In view of this, the purpose of this invention is to provide a kind of motor system that reduces common-mode noise, can reduce common-mode noise and reach safe shutdown.

For reaching above-mentioned purpose, the invention provides a kind of motor system that reduces common-mode noise, this motor system comprises first transformer unit, is electrically connected to described AC power, and exports first direct voltage; Second transformer unit is electrically connected to described AC power, and exports second direct voltage; Control section, it receives described second direct voltage; The optical coupling switch element is electrically connected to described control section, and receives described first direct voltage; The gate drive unit is electrically connected to described optical coupling switch element; Power cell is electrically connected to described gate drive unit, and receives described first direct voltage; Motor is electrically connected to described power cell.

As can be seen from the above technical solutions, the motor system that reduces common-mode noise of the present invention, the direct voltage of its first transformer unit and second transformer unit is the drive part and the control section of feed motor system respectively, and the common-mode noise that therefore can reduce drive part is coupled to control power supply winding via Transformer Winding.Moreover stopping signal can be via optical coupler or relay and close pulsewidth modulated intergrated circuit, to reach the safe shutdown demand.

Description of drawings

Fig. 1 is the power supply supply schematic diagram of known motor-driven system;

Fig. 2 is the block diagram of known motor driven and control system;

Fig. 3 is the foundation motor power device block diagram that reduces common-mode noise of the present invention;

Fig. 4 is the foundation motor system block diagram that reduces common-mode noise of the present invention;

Fig. 5 A is for realizing the circuit diagram of safe shutdown;

Fig. 5 B is for realizing another circuit diagram of safe shutdown.

Description of reference numerals

Exchange (AC) power supply 40 transformer units 42

Igbt drives the power supply 44 of frequency converter and control section

Direct voltage 44A microcontroller 50

Application-specific integrated circuit (ASIC) (ASIC) 52

Interface unit 54 optical coupling switch elements 56

Power cell 58

motors

30,60

Electromagnetic switch 62 stopping signals 64

Exchange (AC) power supply 10 first transformer units 12

Second transformer unit, 14 igbt driving powers 16

Control power supply 18 first direct voltage 16A

The second direct voltage 18A

Microcontroller 20

Application-specific integrated circuit (ASIC) 22

Interface unit 24 optical coupling switch elements 26

Power cell 28 gate drive unit 32

Pulsewidth modulated intergrated circuit 320

Oscillator signal input port 320A

Optical coupler 322 relays 324

Safe shutdown signal (safe stop) 34

Embodiment

Referring to Fig. 3, be the foundation motor power device block diagram that reduces common-mode noise of the present invention.This motor power device that can reduce common-mode noise mainly comprises interchange (AC) power supply 10, exchange first transformer unit 12 and second transformer unit 14 that (AC) power supply 10 is electrically connected with this, IGBT driving power 16 is connected to this first transformer unit 12, and control power supply 18 is connected to this second transformer unit 14.Foregoing circuit constitutes motor power device of the present invention, and driving power and control power supply use transformer independently can avoid coupling noise that driver circuit produces to controlling power supply separately.In this circuit, can comprise the rectifying part (not shown) in this first transformer unit 12 and second transformer unit 14, after changing magnitude of voltage, also can provide direct voltage.

Referring to Fig. 4, be the foundation motor system block diagram that reduces common-mode noise of the present invention.The second direct voltage 18A by 14 supplies of second transformer unit is fed to control section (comprising microcontroller 20, application-specific integrated circuit (ASIC) (ASIC) 22 and interface unit 24 that dotted line surrounds).The first direct voltage 16A that is provided by first transformer unit 12 then is fed to power cell 28, optical coupling switch element 26 and gate drive unit 32, this optical coupling switch element 26 is electrically connected to control section, this gate drive unit 32 is electrically connected to optical coupling switch element 26, and this power cell 28 is electrically connected to gate drive unit 32.

In circuit shown in Figure 4, because the second direct voltage 18A of second transformer unit, 14 supplies is fed to control section, the first direct voltage 16A that first transformer unit 12 provides then is fed to drive part, is electrically connected to the motor 30 of power cell 28 with driving; The common-mode noise that therefore can reduce driving circuit section is coupled to control power supply winding via Transformer Winding.Use the framework of two groups of transformers can obtain clean DC control supply and make that the current circuit of control and the quality of communication are all significantly improved.

Moreover referring to Fig. 5 A and Fig. 4; according to the present invention; safe shutdown signal (safe stop) 34 can make the oscillator signal input port 320A ground connection of the power supply pulsewidth modulated intergrated circuit (PWM IC) 320 within the generation circuit that is positioned at the first direct voltage 16A via being connected in the optical coupler 322 between safe shutdown signal 34 and the oscillator signal input port 320A; therefore power supply that can stop supplies gate drive unit 32; and the igbt (IGBT) in the power cell 28 cuts out, and reach requirement with the simple circuit safe shutdown.

Moreover referring to Fig. 5 B; this safe shutdown signal (safe stop) 34 also can make the oscillator signal input port 320A ground connection of the PWM integrated circuit (PWM IC) 320 within the generation circuit that is positioned at the first direct voltage 16A via being connected in the relay 324 between safe shutdown signal 34 and the oscillator signal input port 320A; power supply that equally can stop supplies gate drive unit 32, and the igbts (IGBT) in the power cell 28 cut out.

Advantage of the present invention can be comprehensively as follows:

1, clean current feedback signal;

2, clean position signalling (encoder);

3, low communication noise;

4, low price safe shutdown (SAFE STOP).

The above is preferred embodiment of the present invention only, is not to be used to limit protection scope of the present invention.

Claims

1. motor system that can reduce common-mode noise, it receives AC power, and it is characterized in that: it comprises:

First transformer unit is electrically connected to described AC power, and exports first direct voltage;

Second transformer unit is electrically connected to described AC power, and exports second direct voltage;

Control section, it receives described second direct voltage;

The optical coupling switch element is electrically connected to described control section, and receives described first direct voltage;

The gate drive unit is electrically connected to described optical coupling switch element;

Power cell is electrically connected to described gate drive unit, and receives described first direct voltage;

Motor is electrically connected to described power cell.

2. the motor system that reduces common-mode noise as claimed in claim 1 is characterized in that: described gate drive unit receives the safe shutdown signal and closes.

3. the motor system that reduces common-mode noise as claimed in claim 1 is characterized in that: described control section comprises microcontroller, application-specific integrated circuit (ASIC) and interface unit.

4. the motor system that reduces common-mode noise as claimed in claim 2 is characterized in that: described first transformer unit comprises pulsewidth modulated intergrated circuit, and described safe shutdown signal makes the oscillator signal input port ground connection of this pulsewidth modulated intergrated circuit.

5. the motor system that reduces common-mode noise as claimed in claim 4; it is characterized in that: this system also comprises so that the optical coupler of this oscillator signal input port ground connection, and described optical coupler is connected between described safe shutdown signal and the described oscillator signal input port.

6. the motor system that reduces common-mode noise as claimed in claim 4; it is characterized in that: this system also comprises so that the relay of this oscillator signal input port ground connection, and described relay is connected between described safe shutdown signal and the described oscillator signal input port.

7. the motor system that reduces common-mode noise as claimed in claim 5 is characterized in that: the power supply of closing described gate drive unit after the described oscillator signal input port ground connection.

8. the motor system that reduces common-mode noise as claimed in claim 6 is characterized in that: the power supply of closing described gate drive unit after the described oscillator signal input port ground connection.

9. the motor system that reduces common-mode noise as claimed in claim 1 is characterized in that: described power cell comprises igbt.