Current detecting apparatus

• US 10,197,604 B2
• Filed: 07/19/2017
• Issued: 02/05/2019
• Est. Priority Date: 09/14/2016
• Status: Active Grant

• Current Assignee: Delta Electronics Incorporated
• Original Assignee: Delta Electronics Incorporated
• Inventors: Wu, Chun-Wei, Lin, Xin-Hung
• Primary Examiner(s): Hiltunen, Thomas J.
• Application Number:
  US15/654,021
• Publication Number:
  US 20180074098A1
• Time in Patent Office: 566 Days
• CPC Class Codes: G01R 19/00 Arrangements for measuring currents or voltages or for indicating presence or sign thereof G01R5/00 takes precedence; for measuring bioelectric currents or voltages A61B5/24
• CPC Class Codes: G01R 19/0015 separating AC and DC
• CPC Class Codes: G01R 19/0069 measuring voltage or current standards
• CPC Class Codes: G01R 19/165 Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values
• CPC Class Codes: G01R 19/18 using conversion of DC into AC, e.g. with choppers
• CPC Class Codes: H02H 7/09 against over-voltage; against reduction of voltage; against phase interruption
• CPC Class Codes: H02P 27/06 using dc to ac converters or inverters H02P27/05 takes precedence

Abstract

A current detecting apparatus measures an input current or an output current of an electronic apparatus. The current detecting apparatus includes a current detecting module, a direct-current measurement module and a current detecting module. The current detecting module includes a coil configured to electromagnetically couple to a path of an input or a path of an output of the electronic apparatus to obtain a first voltage signal. The direct-current measurement module measures the path of the input or the path of the output to obtain a second voltage signal. The current detecting module converts the first voltage signal into a first current command, and converts the second voltage signal into a second current command. The first current command is an alternating-current component of the input current or the output current. The second current command is a direct-current component of the input current or the output current.

Claims

1. A current detecting apparatus connectable to an electronic apparatus to measure a magnitude of an input current or a magnitude of an output current of the electronic apparatus, the current detecting apparatus comprising:

a current sensing module comprising a coil configured to electromagnetically couple to a path of an input of the electronic apparatus to sense the input current and obtain a first input voltage signal, and further configured to electromagnetically couple to a path of an output of the electronic apparatus to sense the output current to obtain a first output voltage signal;

a direct-current measurement module configured to measure the input current at an input inductor of the electronic apparatus to obtain a second input voltage signal, and further configured to measure the output current at an output inductor of the electronic apparatus to obtain a second output voltage signal; and

a current detecting module connected to the coil and the direct-current measurement module,

the current detecting module being configured to convert the first input voltage signal into a first input current command;

convert the second input voltage signal into a second input current command;

convert the first output voltage signal into a first output current command; and

convert the second output voltage signal into a second output current command,

the current detecting module being further configured to output the first input current command;

the second input current command;

the first output current command; and

the second output current command to a control unit of the electronic apparatus,

wherein the first input current command is an alternating-current component of the input current;

the first output current command is an alternating-current component of the output current;

the second input current command is a direct-current component of the input current; and

the second output current command is a direct-current component of the output current.

2. The current detecting apparatus of claim 1, wherein the first input voltage signal is a differential signal corresponding with the alternating-current component of the input current, and the first output voltage signal is a differential signal corresponding with the alternating-current component of the output current.

3. The current detecting apparatus of claim 1, wherein the current detecting module comprises:

an integrator module connected to the coil;

a first gain adjusting module connected between the integrator module and the control unit;

a second gain adjusting module connected to the direct-current measurement module; and

a filtering module connected between the second gain adjusting module and the control unit.

4. The current detecting apparatus of claim 3, wherein the integrator module is configured to perform an integration operation on the first input voltage signal or the first output voltage signal, and wherein the first gain adjusting module is configured to perform a gain adjusting operation to generate the first input current command or the first output current command.

5. The current detecting apparatus of claim 3, wherein the second gain adjusting module is configured to gain-adjust the second input voltage signal or the second output voltage signal, and the filtering module is configured to filter and generate the second input current command or the second output current command.

6. The current detecting apparatus of claim 3, wherein the integrator module comprises:

a first integrator resistor comprising one side of the first integrator resistor connected to one side of the coil;

a first amplifier unit comprising a first input, a second input and a first output, the first input connected to an other side of the first integrator resistor, a second input connected between the other side of the coil and a ground;

a second integrator resistor comprising one side of the second integrator resistor connected to the first input, and an other side of the second integrator resistor connected to the first output; and

a first integrator capacitor comprising one side of the first integrator capacitor connected to the first input, and an other side of the first integrator capacitor connected to the first output.

7. The current detecting apparatus of claim 6, wherein the first gain adjusting module comprises:

a first gain adjusting resistor comprising one side of the first gain adjusting resistor connected to the first output;

a second gain adjusting resistor comprising one side of the second gain adjusting resistor connected to the second input;

a second amplifier unit comprising a third input, a fourth input and a second output, the third input connected to an other side of the first gain adjusting resistor, a fourth input connected to an other side of the second gain adjusting resistor;

a third gain adjusting resistor comprising one side of the third gain adjusting resistor connected to the third input, and an other side of the third gain adjusting resistor connected to the second output; and

a fourth gain adjusting resistor comprising one side of the fourth gain adjusting resistor connected to the fourth input, and an other side of the fourth gain adjusting resistor connected to a reference voltage.

8. The current detecting apparatus of claim 3, wherein the direct-current measurement module is connected to the current detecting module, wherein the direct-current measurement module is further configured to connect to two sides of the input inductor or two sides of the output inductor of the electronic apparatus.

9. The current detecting apparatus of claim 3, wherein the direct-current measurement module comprises:

a direct-current measurement capacitor comprising one side of the direct-current measurement capacitor configured to connect to one side of the input inductor or one side of the output inductor of the electronic apparatus; and

a direct-current measurement resistor comprising one side of the direct-current measurement resistor configured to connect to an other side of the direct-current measurement capacitor, an other side of the direct-current measurement resistor connected to the other side of the input inductor, or an other side of the output inductor of the electronic apparatus,

wherein two sides of the direct-current measurement capacitor are connected to the current detecting module.

10. The current detecting apparatus of claim 8, wherein the second gain adjusting module comprises:

a fifth gain adjusting resistor comprising one side of the fifth gain adjusting resistor configured to connect to one side of the input inductor or one side of the output inductor of the electronic apparatus;

a sixth gain adjusting resistor comprising one side of the sixth gain adjusting resistor configured to connect to an other side of the input inductor or an other side of the output inductor of the electronic apparatus;

a third amplifier unit comprising a fifth input, a sixth input and a third output, the fifth input connected to an other side of the fifth gain adjusting resistor, a sixth input connected to an other side of the sixth gain adjusting resistor;

a seventh gain adjusting resistor comprising one side of the seventh gain adjusting resistor connected to the fifth input, and an other side of the seventh gain adjusting resistor connected to the third output; and

an eighth gain adjusting resistor comprising one side of the eighth gain adjusting resistor connected to the sixth input, and an other side of the eighth gain adjusting resistor connected to a ground.

11. The current detecting apparatus of claim 10, wherein the filtering module comprises:

a first filtering resistor comprising one side of the first filtering resistor connected to the third output;

a second filtering resistor comprising one side of the second filtering resistor connected to an other side of the first filtering resistor;

a first filtering capacitor comprising one side of the first filtering capacitor connected to the other side of the first filtering resistor;

a fourth amplifier unit comprising a seventh input, an eighth input and a fourth output, wherein the seventh input and the fourth output are connected to an other side of the first filtering capacitor, wherein the eighth input is connected to an other side of the second filtering resistor; and

a second filtering capacitor comprising one side of the second filtering capacitor connected to the eighth input, and an other side of the second filtering capacitor connected to a ground.

12. The current detecting apparatus of claim 9, wherein the second gain adjusting module comprises:

a fifth gain adjusting resistor comprising one side of the fifth gain adjusting resistor connected to the one side of the direct-current measurement capacitor;

a sixth gain adjusting resistor comprising one side of the sixth gain adjusting resistor connected to the other side of the direct-current measurement capacitor;

a third amplifier unit comprising a fifth input, a sixth input and a third output, the fifth input connected to the other side of the fifth gain adjusting resistor, a sixth input connected to the other side of the sixth gain adjusting resistor;

a seventh gain adjusting resistor comprising one side of the seventh gain adjusting resistor connected to the fifth input, and an other side of the seventh gain adjusting resistor connected to the third output; and

an eighth gain adjusting resistor comprising one side of the eighth gain adjusting resistor connected to the sixth input, and an other side of the eighth gain adjusting resistor connected to a ground.

13. The current detecting apparatus of claim 12, wherein the filtering module comprises:

a first filtering resistor comprising one side of the first filtering resistor connected to the third output;

a second filtering resistor comprising one side of the second filtering resistor connected to an other side of the first filtering resistor;

a first filtering capacitor comprising one side of the first filtering capacitor connected to the other side of the first filtering resistor;

a fourth amplifier unit comprising a seventh input, an eighth input and a fourth output, wherein the seventh input and the fourth output are connected to an other side of the first filtering capacitor, wherein the eighth input is connected to an other side of the second filtering resistor; and

a second filtering capacitor comprising one side of the second filtering capacitor connected to the eighth input, and an other side of the second filtering capacitor connected to a ground.

14. An operation method for a current detecting apparatus measuring a magnitude of an input current or a magnitude of an output current of an electronic apparatus, the operation method comprising:

(a1) providing a current sensing module to sense the input current of the electronic apparatus to obtain a first input voltage signal, wherein the first input voltage signal is obtained by applying a differential operation to an alternating-current component of the input current and the input current is amplified or reduced in corresponding proportion to obtain the first input voltage signal;

or

(a2) providing the current sensing module to sense the output current of the electronic apparatus to obtain a first output voltage signal, wherein the first output voltage signal is obtained by applying a differential operation to an alternating-current component of the output current and the output current is amplified or reduced in corresponding proportion to obtain the first output voltage signal; and

(b) sensing the input current at an input inductor of the electronic apparatus to obtain a second input voltage signal, or sensing the output current at an output inductor of the electronic apparatus to obtain a second output voltage signal;

(c) performing an integral and gain adjusting operation on the first input voltage signal to generate a first input current command, or performing an integral and gain adjusting operation on the first output voltage signal to generate a first output current command;

(d) gain-adjusting and filtering the second input voltage signal to obtain a second input current command, or gain-adjusting and filtering the second output voltage signal to obtain a second output current command; and

(e) outputting the first input current command and the second input current command to a control unit of the electronic apparatus, or outputting the first output current command and the second output current command to the control unit of the electronic apparatus.