Solar Power
In article ,
"Ed Huntress" wrote: "Joseph Gwinn" wrote in message ... In article , "Ed Huntress" wrote: "Don Foreman" wrote in message ... On Tue, 27 Jul 2010 14:19:15 -0400, "Ed Huntress" wrote: But it was apparent to me from the time you first commented that you must have been absent the day they explained internal phase relationships and force in single-phase motors. g You went so far off base, contending that those motors operate in quadrature and so on (most inentionally do *not* operate in quadrature; it's part of their design to have partially-shifted phases) that I didn't even respond to much of it. Engineers refer to a quadrature component in any case where there is phase difference. It's standard notation. However slight the phase difference is, a quadrature component is necessary to develop torque. The engineers I know, and the electronics I learned when studying for both my amateur and commercial radiotelephone licenses, mean a 90-degree phase shift -- pi/2. Anything else is a phase shift of different proportions -- not quadrature. What kind of engineers call any phase shift "quadrature"? Mathematicians use different meanings for the term, referring to different processes of integration, but I've never heard that usage in engineering applications. The critical word is "component". Any angle can be resolved into the sum of an in-phase component and a quadrature component. http://en.wikipedia.org/wiki/Phase_%...uadrature_.28I .26Q. 29_components Joe Gwinn Of course. But to be "in quadrature" means that the phases are displaced by 90 degrees. Anything else is some other phase shift. For example, in one of the most common types of single-phase motors, the basic split-phase, the starting phase lags the primary phase by, typically, around 30 degrees. Yes, but you were misreading it as applied to the Solar Power thread. Joe |
Solar Power
"Joseph Gwinn" wrote in message ... In article , "Ed Huntress" wrote: "Joseph Gwinn" wrote in message ... In article , "Ed Huntress" wrote: "Don Foreman" wrote in message ... On Tue, 27 Jul 2010 14:19:15 -0400, "Ed Huntress" wrote: But it was apparent to me from the time you first commented that you must have been absent the day they explained internal phase relationships and force in single-phase motors. g You went so far off base, contending that those motors operate in quadrature and so on (most inentionally do *not* operate in quadrature; it's part of their design to have partially-shifted phases) that I didn't even respond to much of it. Engineers refer to a quadrature component in any case where there is phase difference. It's standard notation. However slight the phase difference is, a quadrature component is necessary to develop torque. The engineers I know, and the electronics I learned when studying for both my amateur and commercial radiotelephone licenses, mean a 90-degree phase shift -- pi/2. Anything else is a phase shift of different proportions -- not quadrature. What kind of engineers call any phase shift "quadrature"? Mathematicians use different meanings for the term, referring to different processes of integration, but I've never heard that usage in engineering applications. The critical word is "component". Any angle can be resolved into the sum of an in-phase component and a quadrature component. http://en.wikipedia.org/wiki/Phase_%...uadrature_.28I .26Q. 29_components Joe Gwinn Of course. But to be "in quadrature" means that the phases are displaced by 90 degrees. Anything else is some other phase shift. For example, in one of the most common types of single-phase motors, the basic split-phase, the starting phase lags the primary phase by, typically, around 30 degrees. Yes, but you were misreading it as applied to the Solar Power thread. That may be. Don and I were discussing something we had been talking about back in April and May, in a thread titled "What?" -- Ed Huntress |
Solar Power
On Fri, 30 Jul 2010 09:38:42 -0400, "Ed Huntress"
wrote: "Joseph Gwinn" wrote in message ... In article , "Ed Huntress" wrote: "Don Foreman" wrote in message ... On Tue, 27 Jul 2010 14:19:15 -0400, "Ed Huntress" wrote: But it was apparent to me from the time you first commented that you must have been absent the day they explained internal phase relationships and force in single-phase motors. g You went so far off base, contending that those motors operate in quadrature and so on (most inentionally do *not* operate in quadrature; it's part of their design to have partially-shifted phases) that I didn't even respond to much of it. Engineers refer to a quadrature component in any case where there is phase difference. It's standard notation. However slight the phase difference is, a quadrature component is necessary to develop torque. The engineers I know, and the electronics I learned when studying for both my amateur and commercial radiotelephone licenses, mean a 90-degree phase shift -- pi/2. Anything else is a phase shift of different proportions -- not quadrature. What kind of engineers call any phase shift "quadrature"? Mathematicians use different meanings for the term, referring to different processes of integration, but I've never heard that usage in engineering applications. The critical word is "component". Any angle can be resolved into the sum of an in-phase component and a quadrature component. http://en.wikipedia.org/wiki/Phase_%...ature_.28I.26Q. 29_components Joe Gwinn Of course. But to be "in quadrature" means that the phases are displaced by 90 degrees. Anything else is some other phase shift. Any phasor can be expressed as the vector sum of an inphase component and a quadrature component, wherein the quadrature component is displaced from the inphase component by 90 degrees. For example, in one of the most common types of single-phase motors, the basic split-phase, the starting phase lags the primary phase by, typically, around 30 degrees. In this instance, the starting phase could be expressed as the vector sum (0.866 + j 0.5)M where M is its magnitude. The magnitude of the inphase component is .866M or M cos (30) that of the quadrature component is 0.5M or M sin(30). |
Solar Power
"Don Foreman" wrote in message ... On Fri, 30 Jul 2010 09:38:42 -0400, "Ed Huntress" wrote: "Joseph Gwinn" wrote in message ... In article , "Ed Huntress" wrote: "Don Foreman" wrote in message ... On Tue, 27 Jul 2010 14:19:15 -0400, "Ed Huntress" wrote: But it was apparent to me from the time you first commented that you must have been absent the day they explained internal phase relationships and force in single-phase motors. g You went so far off base, contending that those motors operate in quadrature and so on (most inentionally do *not* operate in quadrature; it's part of their design to have partially-shifted phases) that I didn't even respond to much of it. Engineers refer to a quadrature component in any case where there is phase difference. It's standard notation. However slight the phase difference is, a quadrature component is necessary to develop torque. The engineers I know, and the electronics I learned when studying for both my amateur and commercial radiotelephone licenses, mean a 90-degree phase shift -- pi/2. Anything else is a phase shift of different proportions -- not quadrature. What kind of engineers call any phase shift "quadrature"? Mathematicians use different meanings for the term, referring to different processes of integration, but I've never heard that usage in engineering applications. The critical word is "component". Any angle can be resolved into the sum of an in-phase component and a quadrature component. http://en.wikipedia.org/wiki/Phase_%...ature_.28I.26Q. 29_components Joe Gwinn Of course. But to be "in quadrature" means that the phases are displaced by 90 degrees. Anything else is some other phase shift. Any phasor can be expressed as the vector sum of an inphase component and a quadrature component, wherein the quadrature component is displaced from the inphase component by 90 degrees. Of course. But you weren't talking about a complex phase relationship. You were talking about a second phase that was "in quadrature." You can find definitions for "in quadrature" in any technical resource. It means related as per a quadrant of a cycle -- in other words, displaced by 90 degrees from the reference phase. I decribed the *real* phase relationship as a phase shift that wasn't "in quadrature." You scoffed. d8-) For example, in one of the most common types of single-phase motors, the basic split-phase, the starting phase lags the primary phase by, typically, around 30 degrees. In this instance, the starting phase could be expressed as the vector sum (0.866 + j 0.5)M where M is its magnitude. The magnitude of the inphase component is .866M or M cos (30) that of the quadrature component is 0.5M or M sin(30). Yes. But we were talking about relationships that were "in quadrature." -- Ed Huntress |
Solar Power
On Jul 30, 12:19*pm, "Ed Huntress" wrote:
"Don Foreman" wrote in message ... On Fri, 30 Jul 2010 09:38:42 -0400, "EdHuntress" wrote: "Joseph Gwinn" wrote in message ... In article , "EdHuntress" wrote: "Don Foreman" wrote in message m... On Tue, 27 Jul 2010 14:19:15 -0400, "EdHuntress" wrote: But it was apparent to me from the time you first commented that you must have been absent the day they explained internal phase relationships and force in single-phase motors. g You went so far off base, contending that those motors operate inquadratureand so on (most inentionally do *not* operate inquadrature; it's part of their design to have partially-shifted phases) that I didn't even respond to much of it. Engineers refer to aquadraturecomponent in any case where there is phase difference. *It's standard notation. *However slight the phase difference is, aquadraturecomponent is necessary to develop torque.. The engineers I know, and the electronics I learned when studying for both my amateur and commercial radiotelephone licenses, mean a 90-degree phase shift -- pi/2. Anything else is a phase shift of different proportions -- notquadrature. What kind of engineers call any phase shift "quadrature"? Mathematicians use different meanings for the term, referring to different processes of integration, but I've never heard that usage in engineering applications. The critical word is "component". *Any angle can be resolved into the sum of an in-phase component and aquadraturecomponent. http://en.wikipedia.org/wiki/Phase_%..._and_quadratur.... 29_components Joe Gwinn Of course. But to be "inquadrature" means that the phases are displaced by 90 degrees. Anything else is some other phase shift. Any phasor can be expressed as the vector sum of an inphase component and aquadraturecomponent, wherein thequadraturecomponent is displaced from the inphase component by 90 degrees. Of course. But you weren't talking about a complex phase relationship. You were talking about a second phase that was "inquadrature." You can find definitions for "inquadrature" in any technical resource. It means related as per a quadrant of a cycle -- in other words, displaced by 90 degrees from the reference phase. I decribed the *real* phase relationship as a phase shift that wasn't "inquadrature." You scoffed. d8-) I scoffed at your introduction of the notion of a "drive pulse" in an induction motor with sinusoidal excitation. For example, in one of the most common types of single-phase motors, the basic split-phase, the starting phase lags the primary phase by, typically, around 30 degrees. In this instance, the starting phase could be expressed as the vector sum *(0.866 + j 0.5)M *where M is its *magnitude. *The magnitude of the *inphase component is .866M *or M cos (30) * *that of the quadraturecomponent is 0.5M or *M sin(30). Yes. But we were talking about relationships that were "in quadrature." -- EdHuntress- The two components above are indeed in quadrature, by definition. The term quadrature wasn't used in the previous discussion until the notion of an external two-phase synthesizer was introduced. Such a device would indeed produce two phases that are displaced by 90 degrees. The vector sum of these two components then comprises a rotating vector at synchronous speed. |
Solar Power
"Don" wrote in message ... On Jul 30, 12:19 pm, "Ed Huntress" wrote: "Don Foreman" wrote in message ... On Fri, 30 Jul 2010 09:38:42 -0400, "EdHuntress" wrote: "Joseph Gwinn" wrote in message ... In article , "EdHuntress" wrote: "Don Foreman" wrote in message m... On Tue, 27 Jul 2010 14:19:15 -0400, "EdHuntress" wrote: But it was apparent to me from the time you first commented that you must have been absent the day they explained internal phase relationships and force in single-phase motors. g You went so far off base, contending that those motors operate inquadratureand so on (most inentionally do *not* operate inquadrature; it's part of their design to have partially-shifted phases) that I didn't even respond to much of it. Engineers refer to aquadraturecomponent in any case where there is phase difference. It's standard notation. However slight the phase difference is, aquadraturecomponent is necessary to develop torque. The engineers I know, and the electronics I learned when studying for both my amateur and commercial radiotelephone licenses, mean a 90-degree phase shift -- pi/2. Anything else is a phase shift of different proportions -- notquadrature. What kind of engineers call any phase shift "quadrature"? Mathematicians use different meanings for the term, referring to different processes of integration, but I've never heard that usage in engineering applications. The critical word is "component". Any angle can be resolved into the sum of an in-phase component and aquadraturecomponent. http://en.wikipedia.org/wiki/Phase_%..._and_quadratur.... 29_components Joe Gwinn Of course. But to be "inquadrature" means that the phases are displaced by 90 degrees. Anything else is some other phase shift. Any phasor can be expressed as the vector sum of an inphase component and aquadraturecomponent, wherein thequadraturecomponent is displaced from the inphase component by 90 degrees. Of course. But you weren't talking about a complex phase relationship. You were talking about a second phase that was "inquadrature." You can find definitions for "inquadrature" in any technical resource. It means related as per a quadrant of a cycle -- in other words, displaced by 90 degrees from the reference phase. I decribed the *real* phase relationship as a phase shift that wasn't "inquadrature." You scoffed. d8-) I scoffed at your introduction of the notion of a "drive pulse" in an induction motor with sinusoidal excitation. But that's precisely what it is. The primary phase is the "drive pulse(s)." It provides almost all of the drive in a shade-pole motor; *all* of the drive in a split-phase motor; *all* of the drive in a capacitor-start motor -- and those are the three dominant types of single-phase motors, numerically speaking. The two or three varieties of motors in which the secondary windings are permanently connected (in addition to shaded-pole types) also, for the most part, derive most of their drive from the primary phase. Again, that discussion, from the first post until you introduced the idea of two-phase motors, was entirely about single-phase motors. In fact, the entire issue was about motors driven from a single-phase source. For example, in one of the most common types of single-phase motors, the basic split-phase, the starting phase lags the primary phase by, typically, around 30 degrees. In this instance, the starting phase could be expressed as the vector sum (0.866 + j 0.5)M where M is its magnitude. The magnitude of the inphase component is .866M or M cos (30) that of the quadraturecomponent is 0.5M or M sin(30). Yes. But we were talking about relationships that were "in quadrature." -- EdHuntress- The two components above are indeed in quadrature, by definition. Which "two components"? In most single-phase motors, there is NO quadrature component driving the motor. The 90 degree phase shift provided by inductance or capacitance in the motor is shifted back (or forward, if there is a capacitor in the circuit) to some other phase angle before it delivers magnetic force to the motor. Those motors never actually *run* in quadrature, unlike a true two-phase motor, which you introduced to the discussion. The term quadrature wasn't used in the previous discussion until the notion of an external two-phase synthesizer was introduced. Such a device would indeed produce two phases that are displaced by 90 degrees. The vector sum of these two components then comprises a rotating vector at synchronous speed. The discussion was about single-phase motors. -- Ed Huntress |
Solar Power
On Sat, 31 Jul 2010 15:47:38 -0400, "Ed Huntress"
wrote: The two components above are indeed in quadrature, by definition. Which "two components"? In most single-phase motors, there is NO quadrature component driving the motor. OK, Ed. |
All times are GMT +1. The time now is 10:47 AM. |
Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004 - 2014 DIYbanter