Electric motor car controller

• US 20050264255A1
• Filed: 02/07/2005
• Published: 12/01/2005
• Est. Priority Date: 05/25/2004
• Status: Active Grant

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Azuma, Satoshi, Maruyama, Takafumi
• Granted Patent: US 6,995,540 B2
• Time in Patent Office: Days
• US Class Current: 318/808
• CPC Class Codes: H02P 21/09 Field phase angle calculation based on rotor voltage equation by adding slip frequency and speed proportional frequency

Abstract

An electric motor car controller includes a voltage detector for detecting the voltage across a filter capacitor, an energy amount calculator for calculating the amount of energy of the filter capacitor from the output of the voltage detector, a frequency band component detector for extracting a given frequency band component included in the amount of energy, a frequency band component coefficient unit for multiplying the frequency band component by a coefficient and outputting a q-axis current command correcting value, and a q-axis current command correcting value adder for adding a q-axis current command correcting value to the q-axis current command value to correct the q-axis current command value.

Claims

1. An electric motor car controller for smoothing DC power collected from an overhead wire via a filter reactor and a filter capacitor, converting the DC power into AC power with a power converter, driving a vehicle-driving AC motor, and calculating a voltage command to be applied to the power converter based on a d-axis current command value and a q-axis current command value commanded by a voltage coordinate converter, the electric motor car controller comprising:

a voltage detector for detecting a voltage across the filter capacitor;

an energy amount calculator for calculating an amount of energy of the filter capacitor from the voltage detected by the voltage detector;

a frequency band component detector for extracting a given frequency band component contained in the amount of energy;

a frequency band component coefficient unit for multiplying the frequency band component by a given coefficient and outputting a q-axis current command correcting value; and

a q-axis current command correcting value adder for correcting the q-axis current command value by adding the q-axis current command correcting value to the q-axis current command value.

2. The electric motor car controller as in claim 1, further comprising:

a rotational speed detector for detecting rotational speed of the AC motor;

a rotational speed coefficient unit for outputting a rotational speed coefficient inversely proportional to the rotational speed; and

a rotational speed multiplier for correcting the q-axis current command correcting value according to the rotational speed by multiplying the q-axis current command correcting value by the rotational speed coefficient.

3. The electric motor car controller as in claim 1, further comprising:

a direction command coefficient unit for receiving a motion direction command for forward motion or rearward motion of an electric motor car and outputting a direction coefficient responsive to the motion direction in response to a motion direction command; and

a direction command multiplier for multiplying the q-axis current command correcting value by the direction command coefficient and correcting the q-axis command current correcting value according to the motion direction.

4. The electric motor car controller as in claim 1, further comprising a slip control unit for calculating a slip frequency command for the AC motor using an output from said q-axis current command correcting value adder which adds the q-axis current command value to the q-axis current command correcting value and which corrects the q-axis current command value.

5. An electric motor car controller for smoothing DC power collected from an overhead wire via a filter reactor and a filter capacitor, converting the power into AC power with a power converter, driving a vehicle-driving AC motor, and calculating a voltage command to be applied to the power converter based on a d-axis current command value and a q-axis current command value commanded by a voltage coordinate converter, the electric motor car controller comprising:

a current detector for detecting an electrical current passing through the filter reactor;

an energy amount calculator for calculating an amount of energy of the filter reactor from the current detected by the current detector;

a frequency band component detector for extracting a given frequency band component included in the amount of energy;

a phase compensator for multiplying the frequency band component by a given coefficient, providing phase compensation of the component, and outputting a q-axis current command correcting value; and

a q-axis current command correcting value adder for correcting the q-axis current command value by adding the q-axis current command correcting value to the q-axis current command value.

6. The electric motor car controller as in claim 5, further comprising:

a rotational speed detector for detecting a rotational speed of the AC motor;

a rotational speed coefficient unit for outputting a rotational speed coefficient inversely proportional to the rotational speed; and

a rotational speed multiplier for correcting the q-axis current command correcting value according to the rotational speed by multiplying the q-axis current command correcting value by the rotational speed coefficient.

7. The electric motor car controller as in claim 5, further comprising:

a direction command coefficient unit for receiving a motion direction command for forward motion or rearward motion of an electric motor car and outputting a direction coefficient responsive to the motion direction in response to a motion direction command; and

a direction command multiplier for multiplying the q-axis current command correcting value by the direction command coefficient and correcting the q-axis command current correcting value according to the motion direction.

8. The electric motor car controller as in claim 5, further comprising a slip control unit for calculating a slip frequency command for the AC motor using an output from said q-axis current command correcting value adder which adds the q-axis current command value to the q-axis current command correcting value and which corrects the q-axis current command value.