I claim:
1. A method for determining the state of stability of an electrical grid having n nodes, comprising the steps of:
a. embedding load flow equations (L) representing the electrical grid in a parametric homotopy (L(s)) that goes continuously from a 0-case (L(0)), in which all voltages are equal to the nominal voltage and there is no energy flow in links of the grid, to an objective case (L(1)) representative of the grid in the condition for which stability is to be determined;
b. developing in power series values of the load flow equations’ unknowns in the parameters of the parametric homotopy (L(s)) in a neighborhood of the 0-case value of each parameter;
c. computing a continued fraction approximation to the power series coefficients produced in step b;
d. evaluating the n-order approximant of the continued fraction approximation produced in step c for the power series coefficients produced in step b to provide a solution to the load flow equations (L); and
e. displaying the solution to the load flow equations as a measure of the state of stability of the electrical grid.
2. The method of claim 1, further comprising the steps of:
prior to said embedding step, receiving data from a supervisory and data acquisition system representative of conditions of the electrical grid, and forming said load flow equations (L) from said data.
3. The method of claim 2, further comprising the steps of repeating said receiving step and steps a through e continuously to provide a continuous, real time estimation of the stability of the electrical grid.
4. The method of claim 3, further comprising the steps of confirming that a set of voltages and flows contained in said solution to said load flow equations (L) are representative of a physical electrical state.
5. A method of measuring load flow in a power generating system having an electrical grid comprised of n nodes, comprising the steps of:
a. embedding load flow equations (L) representing the electrical grid in a parametric homotopy (L(s)) that goes continuously from a 0-case (L(0)), in which all voltages are equal to the nominal voltage and there is no energy flow in links of the grid, to an objective case (L(1)) representative of the grid in the condition for which stability is to be determined;
b. developing in power series values of the load flow equations’ unknowns in the parameters of the parametric homotopy (L(s)) in a neighborhood of the 0-case value of each parameter;
c. computing a continued fraction approximation to the power series coefficients produced in step b;
d. evaluating the n-order approximant of the continued fraction approximation produced in step c for the power series coefficients produced in step b to provide a solution to the load flow equations (L); and
e. displaying the solution to the load flow equations as a measure of the load flow in the power generating system.
6. The method of claim 5, further comprising the steps of:
prior to said embedding step, receiving data from a supervisory and data acquisition system representative of conditions of the electrical grid, and forming said load flow equations (L) from said data.
7. The method of claim 6, further comprising the steps of repeating said receiving step and steps a through e continuously to provide a continuous, real time measure of the load flow in the power generating system.
8. A method of measuring load flow in a power generating system having an electrical grid, comprising the steps of:
a. generating a mathematical model of a known, physical solution to the load flow equations (L) in which all voltages are equal to the nominal voltage and there is no energy flow in links of the grid;
b. using analytical continuation to develop a mathematical model of the current, physical solution to the load flow equations representing the current load flow in the power generating system; and
c. displaying the physical solution to the load flow equations as a measure of the load flow in the power generating system.
9. The method of claim 8, said generating step further comprising developing a power series expansion of all quantities in a parametric homotopy (L(s)) formed from said load flow equations (L) in a neighborhood of the 0-case value of each quantity.
10. The method of claim 9, further comprising using algebraic approximants to determine the sum of all coefficients of said power series for the load flow equations representative of the physical current load flow that is to be determined.
11. A system for measuring load flow in a power generating system having an electrical grid, said system comprising:
a supervisory control and data acquisition system adapted to collect data from said electrical grid indicative of electrical conditions in said electrical grid, said supervisory control and data acquisition system being in communication with a microprocessor-controlled energy management system, said energy management system further comprising executable computer instructions to:
a. process said data received from said supervisory control and data acquisition system into load flow equations (L) representing the electrical grid;
b. embed said load flow equations (L) in a parametric homotopy (L(s)) that goes continuously from a 0-case (L(0)), in which all voltage are equal to the nominal voltage and there is no energy flow in links of the grid, to an objective case (L(1)) representative of the grid in the condition for which stability is to be determined;
c. develop in power series values of the load flow equations’ unknowns in the parameters of the parametric homotopy (L(s)) in a neighborhood of the 0-case value of each parameter;
d. compute a continued fraction approximation to the power series coefficients produced in step c;
e. evaluate the n-order approximant of the continued fraction approximation produced in step d for the power series coefficients produced in step c to provide a solution to the load flow equations (L); and
f. display the solution to the load flow equations as a measure of the state of stability of the electrical grid.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A lens barrel assembly of a camera module, comprising:
a barrel in which at least one lens is received, the barrel having a stopping protrusion in a lower-end inner surface thereof to stop the lens; and
a retainer having a horizontal portion which has a lens exposing hole and covers an upper opening of the barrel and a vertical portion which is formed to extend from an outer circumference of the horizontal portion in the optical-axis direction and which an outer surface of the barrel is inserted into,
wherein an overlapped region of the barrel and the horizontal portion is fuse-secured by laser illumination.
2. The lens barrel assembly of claim 1, wherein the barrel is formed as a screwless hollow-cylindrical member which is inserted into the horizontal portion of the retainer.
3. The lens barrel assembly of claim 1,
wherein the barrel further comprises a spacer for maintaining an interval between adjacent lenses, and
wherein the overlapped region is disposed to a position corresponding to the spacer.
4. The lens barrel assembly of claim 3, wherein the spacer is made of a heat-resistance material.
5. The lens barrel assembly of claim 1, wherein the outer surface of the body of the barrel and an inner surface of the vertical portion are in a surface contact with each other and vertically assembled in the overlapped region.
6. A laser apparatus for assembling a lens barrel assembly, comprising:
a lens barrel assembly having a barrel in which at least one lens is received, a retainer which is coupled with an upper-end portion of the barrel, and an overlapped region of the barrel and retainer;
a mounting jig in which the lens barrel assembly is mounted; and
a laser generator which is electrically connected through an optical-fiber cable to a laser output terminal disposed to a position corresponding to the overlapped region of the lens barrel assembly to illuminate the overlapped region with a laser beam having a specific frequency range.
7. The laser apparatus of claim 6,
wherein the mounting jig is formed on an upper surface of a base disposed on a bottom surface, and
wherein the mounting jig is provided with a mounting opening having a predetermined depth in which the lens barrel assembly is mounted.
8. The laser apparatus of claim 6, wherein the laser output terminal selectively illuminates any one of a solid-laser beam, a gas-laser beam, and a liquid-laser beam.