MOTOR DRIVING MODULE AND BRUSHLESS DC MOTOR SYSTEM

• US 20140159632A1
• Filed: 06/05/2013
• Published: 06/12/2014
• Est. Priority Date: 12/10/2012
• Status: Active Grant

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: KIM, Minki, Oh, Jimin, Suk, Jung Hee, Yang, Yil Suk
• Granted Patent: US 9,490,735 B2
• Time in Patent Office: Days
• US Class Current: 318/400.34
• CPC Class Codes: H02P 6/18 without separate position detecting elements
• CPC Class Codes: H02P 6/182 using back-emf in windings
• CPC Class Codes: H02P 6/188 using the voltage difference between the windings H02P6/182 takes precedence

Abstract

A motor driving module is provided which includes a motor driving unit configured to control a PWM inverter on the basis of positional information and a control signal; a PWM inverter configured to output three-phase voltages on the basis of DC power according to control of the motor driving unit; a phase voltage estimating unit configured to output three-phase estimated voltages on the basis of the positional information, the DC power, and a voltage modulation index; and a position detecting unit configured to output the positional information on the basis of the three-phase estimated voltages, wherein the positional information is on an external motor that operates on the basis of the three-phase voltages.

Claims

1. A motor driving module, comprising:

a motor driving unit configured to control a PWM inverter on the basis of positional information and a control signal;

a PWM inverter configured to output three-phase voltages on the basis of DC power according to control of the motor driving unit;

a phase voltage estimating unit configured to output three-phase estimated voltages on the basis of the positional information, the DC power, and a voltage modulation index; and

a position detecting unit configured to output the positional information on the basis of the three-phase estimated voltages,

wherein the positional information is on an external motor that operates on the basis of the three-phase voltages.

2. The motor driving module of claim 1, wherein the voltage modulation index is a predetermined value on the basis of a PWM type.

3. The motor driving module of claim 1, wherein the phase voltage estimating unit comprises:

a sinusoidal signal generator configured to generate a plurality of sinusoidal waves on the basis of the positional information; and

a phase voltage calculating unit configured to calculate three-phase estimated voltages on the basis of the plurality of sinusoidal waves, the voltage modulation index, and the DC power.

4. The motor driving module of claim 3, wherein each of the plurality of sinusoidal waves has the same phase and frequency as those of the fundamental wave components of the three-phase voltages.

5. The motor driving module of claim 1, wherein the position detecting unit comprises:

a back electromotive force (EMF) calculating unit configured to calculate three-phase back EMF on the basis of the three-phase estimated voltages; and

a position information detecting unit configured to detect the positional information on the basis of the three-phase back EMF.

6. The motor driving module of claim 1, wherein the external motor does not include a position sensor that detects a position of a rotor.

7. The motor driving module of claim 1, wherein the three-phase estimated voltages have the same phases and frequencies as those of the fundamental wave components.

8. A brushless direct current (BLDC) motor system, comprising:

a motor driving unit configured to control a PWM inverter on the basis of positional information and a control signal;

a PWM inverter configured to output three-phase voltages on the basis of DC power according to control of the motor driving unit;

a BLDC motor configured to operate on the basis of the three-phase voltages;

a phase voltage estimating unit configured to output three-phase estimated voltages on the basis of the positional information, the DC power, and a voltage modulation index; and

a position detecting unit configured to output the positional information on the basis of the three-phase estimated voltages.

9. The BLDC motor system of claim 8, wherein the positional information indicates on a rotor that is included in the BLDC motor.

10. The BLDC motor system of claim 8, wherein the BLDC motor does not include a position sensor that detects a position of a rotor.

11. A operating method for a motor driving module controlling a BLDC motor, comprising:

generating three-phase estimated voltages on the basis of a control signal, a voltage modulation index, and positional information;

calculating three-phase back EMF on the basis of the generated three-phase estimated voltages; and

outputting positional information on the basis of the calculated three-phase back EMF,

wherein the voltage modulation index is determined on the basis of a PWM type of power that is applied to the BLDC motor, and the positional information is on a rotor that is included in the BLDC motor.

12. The operating method of claim 11, wherein the generating of the three-phase estimated voltages comprises:

generating a plurality of sinusoidal waves on the basis of the positional information; and

generating three-phase estimated voltages on the basis of the generated plurality of sinusoidal waves and the voltage modulation index.

13. The operating method of claim 12, wherein each of the plurality of sinusoidal waves has the same phase and frequency as those of fundamental wave components of three-phase voltage that is applied to the BLDC motor.