초록 ▼

The present invention provides a control algorithm which instantaneously detects magnetic pole positions in the inside of a motor including polarities of the motor. A controller 1 applies a minute voltage change vhd to a voltage command on a dc axis which constitutes an estimation magnetic pole axis

The present invention provides a control algorithm which instantaneously detects magnetic pole positions in the inside of a motor including polarities of the motor. A controller 1 applies a minute voltage change vhd to a voltage command on a dc axis which constitutes an estimation magnetic pole axis of the motor 3, detects electric currents Idc, Iqc of a motor 3 and discriminates the polarities of the magnetic pole axes by making use of the difference between a cycle in which ripple components of the electric currents Idc, Iqc become positive and a cycle in which the ripple components become negative or the difference between positive-side and negative-side current change rates. Further, the minute voltage change vhd with respect to the above-mentioned voltage command is generated on both of the dc axis and the qc axis rectangular thereto, and the magnetic pole positions of the motor are directly estimated based on the current ripple components on the respective axes. Without separately providing a cycle for discriminating the polarities of the magnetic poles, the cycle from the turning-on of a power source to the starting of the motor can be shortened so that the high-speed starting of the motor can be realized.

대표청구항 ▼

The present invention provides a control algorithm which instantaneously detects magnetic pole positions in the inside of a motor including polarities of the motor. A controller 1 applies a minute voltage change vhd to a voltage command on a dc axis which constitutes an estimation magnetic pole axis

The present invention provides a control algorithm which instantaneously detects magnetic pole positions in the inside of a motor including polarities of the motor. A controller 1 applies a minute voltage change vhd to a voltage command on a dc axis which constitutes an estimation magnetic pole axis of the motor 3, detects electric currents Idc, Iqc of a motor 3 and discriminates the polarities of the magnetic pole axes by making use of the difference between a cycle in which ripple components of the electric currents Idc, Iqc become positive and a cycle in which the ripple components become negative or the difference between positive-side and negative-side current change rates. Further, the minute voltage change vhd with respect to the above-mentioned voltage command is generated on both of the dc axis and the qc axis rectangular thereto, and the magnetic pole positions of the motor are directly estimated based on the current ripple components on the respective axes. Without separately providing a cycle for discriminating the polarities of the magnetic poles, the cycle from the turning-on of a power source to the starting of the motor can be shortened so that the high-speed starting of the motor can be realized. ons 217 to 220 and offset region are disposed in an n-channel TFT 304 which forms a pixel section, and a TFT structure of low OFF current value is realized. Further, by reducing the n-type impurity element contained in Loff regions 217 to 220 to approximately 1×1016to 5×1018atoms/cm3,further reduction of OFF current can be performed. it. 22. The device according to claim 20, wherein the housing has a base portion which is disposed between the optical emitter and the optical detector for allowing light to be transmitted from the optical emitter to the optical detector. 23. The device according to claim 20, wherein the sample cell and the housing each have sidewalls disposed at an angle of about 60 degrees from a plane extending between the optical emitter and the optical detector. 24. A device for monitoring the flow of a liquid, the device comprising: a sample cell having a cell wall with at least two sidewalls disposed at an angle of between 45 and 100 degrees from one another and defining a conduit; a housing disposed adjacent to but spaced apart from the sample cell so as to define an air chamber between the housing and the sample cell. 25. The device according to claim 24, further comprising an optical emitter and an optical detector disposed on opposing sides of the housing. 26. The device according to claim 24, wherein the housing has at least two sidewalls disposed substantially parallel to the sidewalls of the cell wall. 27. The device according to claim 24, consisting of a single optical detector. 28. The device according to claim 27, wherein the device comprises means for determining if the sample cell is properly positioned in the housing, means for determining if the optical emitter is working, and means for determining if there is air or liquid in the conduit. 29. The device according to claim 28, wherein the means for determining if the sample cell is properly positioned in the housing, the means for determining if the optical emitter is working, and the means for determining if there is air or liquid in the conduit is the single optical emitter. 30. A bubble detection system comprising the sample cell according to claim 1, and further comprising an optical signal emitter and an optical signal detector. 31. The device according to claim 30, wherein the base portion of the sample cell is disposed to transmit light between the optical emitter and the optical detector uninterrupted by contents of the conduit. 32. A sample cell for use in monitoring of air bubbles in an infusion set, the sample cell comprising a conduit and a base portion extending from the sample cell configured to allow light to pass therethrough regardless of contents of the conduit. 33. The sample cell of claim 32, wherein the sample cell comprises first and second sidewalls disposed tangentially to one another at an angle of between about 45 to 100 degrees. 34. The sample cell according to claim 33, wherein the base portion is configured to allow light to pass therethrough generally horizontally with minimal refraction. 35. An air bubble sensor system comprising a sample cell in accordance with claim 32, further comprising an optical signal emitter and an optical signal detector. 36. The air bubble sensor system according to claim 35, wherein the optical signal emitter is disposed adjacent the first sidewall and wherein the optical signal detector is disposed adjacent the second sidewall. 37. The air bubble sensor system according to claim 36, wherein a light emission plane extends from the optical signal emitter to the optical signal detector, and wherein each sidewall has an acute angle from the light emission plane which is substantially the same as the acute angle from the light emission plane of the other sidewall. 38. The air bubble sensor system according to claim 37, wherein both the first and second sidewalls are disposed 60 degrees from the light emission plane. 39. The air bubble sensor system according to claim 35, further comprising a housing disposed adjacent to the sample cell. 40. The air bubble sensor system according to claim 39, wherein the housing is disposed between the sample cell and the optical signal emitter and the optical signal sensor. 41. The air bubble sensor system according to claim 40, wherein the housing has a sidewall disposed general