SPEED COMMAND CORRECTION DEVICE AND PRIMARY MAGNETIC FLUX COMMAND GENERATION DEVICE
1 Assignment
0 Petitions
Accused Products
Abstract
A subtractor subtracts an angular speed correction amount from a rotational speed command to obtain a corrected rotational speed command. An adder adds a second-axis current correction value to a γc-axis current to obtain a corrected second-axis current. An angular ripple extraction unit obtains, from a rotational angle on a mechanical angle of a synchronous motor, a rotational angle difference being a ripple component of the rotational angle. An nth-order component extraction unit extracts nth-order components of a fundamental frequency of the rotational angle from the rotational angle difference. A torque conversion unit obtains nth-order components of an estimated value of vibration torque. A correction amount calculation unit obtains the second-axis current correction value using the nth-order components.
-
Citations
40 Claims
-
1-15. -15. (canceled)
-
16. A speed command correction device for correcting a rotational speed command in a method of matching a primary magnetic flux with a primary magnetic flux command in a first axis on a basis of said primary magnetic flux command and said rotational speed command, said rotational speed command being a command value of a rotational speed on an electrical angle of a synchronous motor for driving a periodic load, said primary magnetic flux being a composite of a magnetic flux generated by a current flowing through said synchronous motor and a field magnetic flux of said synchronous motor, said first axis leading said field magnetic flux by a predetermined phase difference, said device comprising:
-
a first subtractor that subtracts an angular speed correction amount from said rotational speed command to obtain a corrected rotational speed command; an adder that adds a second-axis current correction value to a second-axis current to obtain a corrected second-axis current, said second-axis current being a component of said current in a second axis leading said first axis by an electrical angle of 90 degrees; a DC part removal unit that removes a DC part from said corrected second-axis current to obtain said angular speed correction amount; an angular ripple extraction unit that obtains a rotational angle difference from a rotational angle on a mechanical angle of said synchronous motor, said rotational angle difference being a ripple component of said rotational angle to a time integral of an average value of an angular speed of said mechanical angle; a component extraction unit that extracts an nth-order component of a fundamental frequency of said rotational angle from said rotational angle difference, n being a positive integer; a torque conversion unit that converts said nth-order component into an nth-order component of an estimated value of vibration torque of said synchronous motor; and a correction amount calculation unit that receives, as an input, said nth-order component of said estimated value, and obtains said second-axis current correction value using an input into said correction amount calculation unit. - View Dependent Claims (26, 29, 32, 35, 38)
-
-
17. A speed command correction device for correcting a rotational speed command in a method of matching a primary magnetic flux with a primary magnetic flux command in a first axis on a basis of said primary magnetic flux command and said rotational speed command, said rotational speed command being a command value of a rotational speed on an electrical angle of a synchronous motor for driving a periodic load, said primary magnetic flux being a composite of a magnetic flux generated by a current flowing through said synchronous motor and a field magnetic flux of said synchronous motor, said first axis leading said field magnetic flux by a predetermined phase difference, said device comprising:
-
a first subtractor that subtracts an angular speed correction amount from said rotational speed command to obtain a corrected rotational speed command; an adder that adds a second-axis current correction value to a second-axis current to obtain a corrected second-axis current, said second-axis current being a component of said current in a second axis leading said first axis by an electrical angle of 90 degrees; a DC part removal unit that removes a DC part from said corrected second-axis current to obtain said angular speed correction amount; an output torque estimation unit that obtains an estimated value of output torque of said synchronous motor from said primary magnetic flux, a first-axis current, and said second-axis current, said first-axis current being a component of said current in said first axis; a component extraction unit that extracts, from said estimated value, an nth-order component of a fundamental frequency of a rotational angle as a mechanical angle of said synchronous motor, n being a positive integer; and a correction amount calculation unit that receives said nth-order component as an input, and obtains said second-axis current correction value using said input into said correction amount calculation unit. - View Dependent Claims (27, 30, 33, 36, 39)
-
-
18. A speed command correction device for correcting a rotational speed command in a method of matching a primary magnetic flux with a primary magnetic flux command in a first axis on a basis of said primary magnetic flux command and said rotational speed command, said rotational speed command being a command value of a rotational speed on an electrical angle of a synchronous motor for driving a periodic load, said primary magnetic flux being a composite of a magnetic flux generated by a current flowing through said synchronous motor and a field magnetic flux of said synchronous motor, said first axis leading said field magnetic flux by a predetermined phase difference, said device comprising:
-
a first subtractor that subtracts an angular speed correction amount from said rotational speed command to obtain a corrected rotational speed command; an adder that adds a second-axis current correction value to a second-axis current to obtain a corrected second-axis current, said second-axis current being a component of said current in a second axis leading said first axis by an electrical angle of 90 degrees; a DC part removal unit that removes a DC part from said corrected second-axis current to obtain said angular speed correction amount; an angular ripple extraction unit that obtains a rotational angle difference from a rotational angle on a mechanical angle of said synchronous motor, said rotational angle difference being a ripple component of said rotational angle to a time integral of an average value of an angular speed of said mechanical angle; a first component extraction unit that extracts an nth-order component of a fundamental frequency of said rotational angle from said rotational angle difference, n being a positive integer; a torque conversion unit that converts said nth-order component into an nth-order component of an estimated value of vibration torque of said synchronous motor; an output torque estimation unit that obtains an estimated value of output torque of said synchronous motor from said primary magnetic flux, a first-axis current, and said second-axis current, said first-axis current being a component of said current in said first axis; a second component extraction unit that extracts an nth-order component of said fundamental frequency from said estimated value of output torque; a proration unit that prorates said nth-order component obtained by said torque conversion unit and said nth-order component extracted by said second component extraction unit with a predetermined proration rate to respectively obtain a first value and a second value; an adder that obtains a sum of said first value and said second value; and a correction amount calculation unit that receives said sum as an input, and obtains said second-axis current correction value using said input into said correction amount calculation unit. - View Dependent Claims (19, 20, 21, 22, 23, 24, 25, 28, 31, 34, 37, 40)
-
Specification