2010 FEH A/C compressor is electric not belt driven
#11
09-03-2009, 01:56 PM
Re: 2010 FEH A/C compressor is electric not belt driven
In my 06 FEH the A/C compressor is cycled to regulate load, your statement about not being appropriate for hybrid cars notwithstanding. In my FEH the A/C compressor only operates when the engine is on unless max is selected and then the engine remains on continuously.
Though I do not own a more recent FEH with an electric motor driven compressor my suspicion is that this first system will use a constant speed motor to power the compressor. The rest of the system can then be an off the shelf A/C setup and the motor needs a very simple motor controller.
What your posts indicate is a lack of understanding of how freon (or other liquids appropriate to A/C systems) work. The saturated liquid & gas pressures tell the A/C system what the load on the system is and how to regulate the flow of freon around the system.
A receiver is not even necessary to the system (although it is a good idea). With the simplified CCOT (Cycling Clutch Orifice Tube) arrangement where there is not a variable orifice in the system to regulate flow, the flow is regulated by cycling the compressor on & off.
When you bring in this kind of system the receiver that you're referring to for level is necessary since the orifice does not regulate flow the pressures across it do. These pressures are controlled by the pressures available as the compressor itself is cycled.
But in the end, if you understand the refrigerant cycle, your statement about liquid level is just bogus.
Though I do not own a more recent FEH with an electric motor driven compressor my suspicion is that this first system will use a constant speed motor to power the compressor. The rest of the system can then be an off the shelf A/C setup and the motor needs a very simple motor controller.
What your posts indicate is a lack of understanding of how freon (or other liquids appropriate to A/C systems) work. The saturated liquid & gas pressures tell the A/C system what the load on the system is and how to regulate the flow of freon around the system.
A receiver is not even necessary to the system (although it is a good idea). With the simplified CCOT (Cycling Clutch Orifice Tube) arrangement where there is not a variable orifice in the system to regulate flow, the flow is regulated by cycling the compressor on & off.
When you bring in this kind of system the receiver that you're referring to for level is necessary since the orifice does not regulate flow the pressures across it do. These pressures are controlled by the pressures available as the compressor itself is cycled.
But in the end, if you understand the refrigerant cycle, your statement about liquid level is just bogus.
#12
09-03-2009, 02:16 PM
Re: 2010 FEH A/C compressor is electric not belt driven
08FEH - As I see it Ford has had to go through a rethinking process with the hybrid system. Using the HV battery as a power supply when they had been using the serpentine belt for so many years just took them awhile.
In the case of power steering the issue was quite obvious: how do you maintain power steering when the ICE is off since the old power steering units were powered off the serpentine belt system. Well, when you have this relatively powerful (if not all that big) battery you can use that power all the time regardless of engine status.
Well then, I suppose your 08 is like my 06, when the engine is off & as you are trying to get more miles per gallon by stretching those battery intervals... and its summertime, it can get a little warm inside after the residual coolness from the system is used up.
So a rethinking of the system tells you that you could use an electric motor to drive the A/C instead of the belt. This while the ICE is in the off mode and thus keep the inside cooler.
Since you have this high voltage power supply (they could do this with a 12v motor but it might be kind of big to provide the required power) you can use a reasonably sized motor instead of a serpentine belt driven input to the compressor.
Yes, the ICE will cycle more frequently. A/C requires a few horsepower to run it after all and that power has to come from the ICE in the end.
In the case of power steering the issue was quite obvious: how do you maintain power steering when the ICE is off since the old power steering units were powered off the serpentine belt system. Well, when you have this relatively powerful (if not all that big) battery you can use that power all the time regardless of engine status.
Well then, I suppose your 08 is like my 06, when the engine is off & as you are trying to get more miles per gallon by stretching those battery intervals... and its summertime, it can get a little warm inside after the residual coolness from the system is used up.
So a rethinking of the system tells you that you could use an electric motor to drive the A/C instead of the belt. This while the ICE is in the off mode and thus keep the inside cooler.
Since you have this high voltage power supply (they could do this with a 12v motor but it might be kind of big to provide the required power) you can use a reasonably sized motor instead of a serpentine belt driven input to the compressor.
Yes, the ICE will cycle more frequently. A/C requires a few horsepower to run it after all and that power has to come from the ICE in the end.
#13
09-03-2009, 06:40 PM
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Re: 2010 FEH A/C compressor is electric not belt driven
Not clearly a "given"...
The electrically driven compressor should be put in the same category as the electric drive motors, sometimes they run for FREE. Whereas the mechanically driven compressor ALWAYS requires the ICE to consume fossil fuel.
#14
09-03-2009, 06:53 PM
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Re: 2010 FEH A/C compressor is electric not belt driven
In my 06 FEH the A/C compressor is cycled to regulate load, your statement about not being appropriate for hybrid cars notwithstanding. In my FEH the A/C compressor only operates when the engine is on unless max is selected and then the engine remains on continuously.
Though I do not own a more recent FEH with an electric motor driven compressor my suspicion is that this first system will use a constant speed motor to power the compressor. The rest of the system can then be an off the shelf A/C setup and the motor needs a very simple motor controller.
What your posts indicate is a lack of understanding of how freon (or other liquids appropriate to A/C systems) work. The saturated liquid & gas pressures tell the A/C system what the load on the system is and how to regulate the flow of freon around the system.
A receiver is not even necessary to the system (although it is a good idea). With the simplified CCOT (Cycling Clutch Orifice Tube) arrangement where there is not a variable orifice in the system to regulate flow, the flow is regulated by cycling the compressor on & off.
When you bring in this kind of system the receiver that you're referring to for level is necessary since the orifice does not regulate flow the pressures across it do. These pressures are controlled by the pressures available as the compressor itself is cycled.
But in the end, if you understand the refrigerant cycle, your statement about liquid level is just bogus.
Though I do not own a more recent FEH with an electric motor driven compressor my suspicion is that this first system will use a constant speed motor to power the compressor. The rest of the system can then be an off the shelf A/C setup and the motor needs a very simple motor controller.
What your posts indicate is a lack of understanding of how freon (or other liquids appropriate to A/C systems) work. The saturated liquid & gas pressures tell the A/C system what the load on the system is and how to regulate the flow of freon around the system.
A receiver is not even necessary to the system (although it is a good idea). With the simplified CCOT (Cycling Clutch Orifice Tube) arrangement where there is not a variable orifice in the system to regulate flow, the flow is regulated by cycling the compressor on & off.
When you bring in this kind of system the receiver that you're referring to for level is necessary since the orifice does not regulate flow the pressures across it do. These pressures are controlled by the pressures available as the compressor itself is cycled.
But in the end, if you understand the refrigerant cycle, your statement about liquid level is just bogus.
Sorry, but given the state of the art in HV solid state electronics that would be just patently stupid on the part of Ford. When even the non-hybrid vehicles are being converted to variable displacement compressor to improve FE why would a hybrid stay with an obsolete technique..??
Bang-bang, on and off, "servo" compressor drive REQUIRES some level of liquid refrigerant in RESERVE. The only time the compressor will run continously is when the liquid refrigerant is being "consumed" as fast as the compressor/condensor can convert the gas back into a liquid. That can happen often with the ICE at/near idle or in extreme, HOT, climatic conditions.
#15
09-04-2009, 02:23 PM
Re: 2010 FEH A/C compressor is electric not belt driven
08FEH - As I see it Ford has had to go through a rethinking process with the hybrid system. Using the HV battery as a power supply when they had been using the serpentine belt for so many years just took them awhile.
In the case of power steering the issue was quite obvious: how do you maintain power steering when the ICE is off since the old power steering units were powered off the serpentine belt system. Well, when you have this relatively powerful (if not all that big) battery you can use that power all the time regardless of engine status.
Well then, I suppose your 08 is like my 06, when the engine is off & as you are trying to get more miles per gallon by stretching those battery intervals... and its summertime, it can get a little warm inside after the residual coolness from the system is used up.
So a rethinking of the system tells you that you could use an electric motor to drive the A/C instead of the belt. This while the ICE is in the off mode and thus keep the inside cooler.
Since you have this high voltage power supply (they could do this with a 12v motor but it might be kind of big to provide the required power) you can use a reasonably sized motor instead of a serpentine belt driven input to the compressor.
Yes, the ICE will cycle more frequently. A/C requires a few horsepower to run it after all and that power has to come from the ICE in the end.
In the case of power steering the issue was quite obvious: how do you maintain power steering when the ICE is off since the old power steering units were powered off the serpentine belt system. Well, when you have this relatively powerful (if not all that big) battery you can use that power all the time regardless of engine status.
Well then, I suppose your 08 is like my 06, when the engine is off & as you are trying to get more miles per gallon by stretching those battery intervals... and its summertime, it can get a little warm inside after the residual coolness from the system is used up.
So a rethinking of the system tells you that you could use an electric motor to drive the A/C instead of the belt. This while the ICE is in the off mode and thus keep the inside cooler.
Since you have this high voltage power supply (they could do this with a 12v motor but it might be kind of big to provide the required power) you can use a reasonably sized motor instead of a serpentine belt driven input to the compressor.
Yes, the ICE will cycle more frequently. A/C requires a few horsepower to run it after all and that power has to come from the ICE in the end.
I look at it a bit differently. Electric compressors have been around for many years (it is old technology), and they had to have seen Toyota implement it in 2003. I think Ford has had this in the plans for years, but wanted to wait until Gen 2 of the FEH (2009 for the mechanical changes vice sheet metal redesign in 2008); they seem to have gone to a 5 year product cycle on their vehicles...
#16
09-04-2009, 03:00 PM
Re: 2010 FEH A/C compressor is electric not belt driven
With a mechanical belt the loading is an obvious mechanical drag on the engine.
An electric motor driven compressor will cause roughly the same load as a belt driven compressor of the same capacity. When the ICE is running the electric compressor can pull electric power directly from the MG at fairly high efficiency, much like a pure series hybrid drive train. The efficiency of the electric compressor is much, much worse when the ICE is off and power needs to be obtained from the batteries. The reason for this is that charging and discharging batteries is very inefficient. The power to recharge the batteries must ultimately come from the ICE so you are paying for your "FREE" power at a later time, like buying on credit.
That said, I still consider the new electric system to be an advantage for several reasons.
1) I'm not a big fan of belts because belts wear out and slip or break.
2) The electric system can provide cooling during an auto-stop which might save a little energy over having the engine at idle just to power the AC.
#17
09-04-2009, 03:06 PM
Re: 2010 FEH A/C compressor is electric not belt driven
This running for "free" idea seems to be a common misconception with non-plug in hybrids. A compressor will always be a load on the system regardless of the driving mechanism.
....
That said, I still consider the new electric system to be an advantage for several reasons.
1) I'm not a big fan of belts because belts wear out and slip or break.
2) The electric system can provide cooling during an auto-stop which might save a little energy over having the engine at idle just to power the AC.
....
That said, I still consider the new electric system to be an advantage for several reasons.
1) I'm not a big fan of belts because belts wear out and slip or break.
2) The electric system can provide cooling during an auto-stop which might save a little energy over having the engine at idle just to power the AC.
#18
09-04-2009, 04:52 PM
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Join Date: Sep 2006
Location: Beautiful Pacific NW
Posts: 1,678
Re: 2010 FEH A/C compressor is electric not belt driven
This running for "free" idea seems to be a common misconception with non-plug in hybrids.
What...,??..., NO...!
recovering energy that would otherwise be WASTED via heating of the frictional brakes can for all purposes be considered FREE. Certainly so in comparison to non-hybrid vehicle.
Now, no one should be of the mind that 100% of the power used to recharge the hybrid battery is free but clearly some of it is, will be.
PS: I am NOT a big fan of regaining energy via simulation of engine compression braking during coastdown periods, I think it to be a net waste, but then I'm not in the design seat.
A compressor will always be a load on the system regardless of the driving mechanism.
But with an electrically driven one at least some of the energy will only be indirectly from a fossil fuel source, regen braking.
With a mechanical belt the loading is an obvious mechanical drag on the engine.
An electric motor driven compressor will cause roughly the same load as a belt driven compressor of the same capacity. When the ICE is running the electric compressor can pull electric power directly from the MG at fairly high efficiency, much like a pure series hybrid drive train.
Well, no, again...
Assuming the compressor is driven by a variable frequency inverter the DC input power MUST come directly from the hybrid battery, NOT from the genset.
Well efficiency of the electric compressor is much, much worse when the ICE is off and power needs to be obtained from the batteries. The reason for this is that charging and discharging batteries is very inefficient.
Agreed, but you are overlooking an important point, the ability to turn the compressor s l o w l y. low power, match the compressor pump volume to the load, with the electrics.
The power to recharge the batteries must ultimately come from the ICE so you are paying for your "FREE" power at a later time, like buying on credit.
Again, there is NO advantage to a hybrid except in comparison to non-hybrid. Hybrids run at least part of the time on FREE energy in comparison.
That said, I still consider the new electric system to be an advantage for several reasons.
1) I'm not a big fan of belts because belts wear out and slip or break.
2) The electric system can provide cooling during an auto-stop which might save a little energy over having the engine at idle just to power the AC.
What...,??..., NO...!
recovering energy that would otherwise be WASTED via heating of the frictional brakes can for all purposes be considered FREE. Certainly so in comparison to non-hybrid vehicle.
Now, no one should be of the mind that 100% of the power used to recharge the hybrid battery is free but clearly some of it is, will be.
PS: I am NOT a big fan of regaining energy via simulation of engine compression braking during coastdown periods, I think it to be a net waste, but then I'm not in the design seat.
A compressor will always be a load on the system regardless of the driving mechanism.
But with an electrically driven one at least some of the energy will only be indirectly from a fossil fuel source, regen braking.
With a mechanical belt the loading is an obvious mechanical drag on the engine.
An electric motor driven compressor will cause roughly the same load as a belt driven compressor of the same capacity. When the ICE is running the electric compressor can pull electric power directly from the MG at fairly high efficiency, much like a pure series hybrid drive train.
Well, no, again...
Assuming the compressor is driven by a variable frequency inverter the DC input power MUST come directly from the hybrid battery, NOT from the genset.
Well efficiency of the electric compressor is much, much worse when the ICE is off and power needs to be obtained from the batteries. The reason for this is that charging and discharging batteries is very inefficient.
Agreed, but you are overlooking an important point, the ability to turn the compressor s l o w l y. low power, match the compressor pump volume to the load, with the electrics.
The power to recharge the batteries must ultimately come from the ICE so you are paying for your "FREE" power at a later time, like buying on credit.
Again, there is NO advantage to a hybrid except in comparison to non-hybrid. Hybrids run at least part of the time on FREE energy in comparison.
That said, I still consider the new electric system to be an advantage for several reasons.
1) I'm not a big fan of belts because belts wear out and slip or break.
2) The electric system can provide cooling during an auto-stop which might save a little energy over having the engine at idle just to power the AC.
#19
09-04-2009, 05:44 PM
Re: 2010 FEH A/C compressor is electric not belt driven
I suppose that if someone was able to drive their hybrid in such a way that forced charging never took place, the energy to run the AC could be considered free if it all came from regeneration.
I'm not familiar enough with the 2010 FEH to say for sure but I seriously doubt that the compressor must run off batteries. This could just be a misunderstanding of terminology. For example:
With a regular car and a standard alternator, I would say that the lights were lit by the alternator while the engine is running and by the battery if the engine is off. The reason is that while the engine is running the system voltage is around 14VDC, 2 Volts higher than the battery is capable of putting out by itself. The flow of power is from the alternator to the battery and also from the alternator to the lights. There is no way the battery can output any power if the system voltage is 14VDC. I'm sure you have seen a car's lights dim when engine is switched off.
I'm talking about the AC in the FEH the same way. The AC may hooked up to the battery but the battery gets a charge from where?
I'm not familiar enough with the 2010 FEH to say for sure but I seriously doubt that the compressor must run off batteries. This could just be a misunderstanding of terminology. For example:
With a regular car and a standard alternator, I would say that the lights were lit by the alternator while the engine is running and by the battery if the engine is off. The reason is that while the engine is running the system voltage is around 14VDC, 2 Volts higher than the battery is capable of putting out by itself. The flow of power is from the alternator to the battery and also from the alternator to the lights. There is no way the battery can output any power if the system voltage is 14VDC. I'm sure you have seen a car's lights dim when engine is switched off.
I'm talking about the AC in the FEH the same way. The AC may hooked up to the battery but the battery gets a charge from where?
#20
09-04-2009, 05:51 PM
Re: 2010 FEH A/C compressor is electric not belt driven
Toyota has taken this to the logical end with the 2010 Prius and eliminated belts completely.
Hopefully Ford will also take steps to minimize or eliminate belts.I'd love to be able to afford one of those new belt-less Priuses (say that 3 times fast).
