Automatic Synchronizing and Load Sharing

We have 2 units of GE DG rated at 11KV 2.4MW operating as Island Mode when there is a power failure.

Both prime-movers are controlled by Woodward 2301 speed controller, its load sharing function disabled, speed setting/load controls signal biased from DSLC.

Each DG has a Woodward DSLC controller to perform automatic synchronization and load sharing.

Alternators are of LS, is modular AVR consists
of a digital trimmer/VAR/PF control module.

The system commissioned 20 years ago,.but noted no one ever attempt to operate the generators in parallel operation.

I have several attempts to perform automatic synchronizing unsucessfully, units always swing load from one to another upon closing incoming unit VCB and render to reversed power tripping in pretty short time, probably less than a m1/2 minute.

Operating in manual mode in Droop mode was stable and can easily manipulate active and reactive load.

Current practice in manual synchronizing and load sharing during monthly load test.

PT and CT polarity checked to be in good order.

Software of DSLC not available to view MW/Mvar in DSLC.

Company not willing to spend money engaging Woodward service personnel.

Seeking anyone's expertise advice to help in solving this problem.
 
CH Lee,

Do you have the manuals for the 2301's and DSLC's?

Most of the Woodward manuals are reasonable good at explaining options (though their explanation of Droop Speed Control leaves a LOT to be desired!!!).

Does each generator connect to a common bus through its own transformer? Or do they connect to the common bus directly?

I'm not a DSLC person, nor a 2301 person. In general, it would be common to operate one DG in Isochronous Speed Control--and this unit would adjust its load AUTOMATICALLY to control frequency. A second (or third or fourth) DG could be synchronized to the bus in Droop Speed Control and as it is manually loaded by the operator you would observe the first DG (operating in Isoch) reduce it's load to maintain frequency. It should be possible to automatically synchronize a second generator if the option is available and can be changed without software. Load sharing could be programmed to try to automatically control the amount of load on each DG as load changed. Personally, I don't think this works really well in real-world practice, though Woodward DSLC's are better than most other load-sharing schemes. For a simple two-generator set-up as long as one unit is in Isoch Speed Control mode and the other one is in Droop Speed Control mode, everything should be pretty stable.

When it comes time to re-synchronize the two units to the grid, if the load on the island is stable, switch the Isoch machine to Droop Speed Control and then use either generator to control frequency and close the tie breaker. Both DGs will be in Droop Speed Control mode and all will be good. Then, each generator can be manually unloaded and separated from the grid without upsetting anything.

This description is only for islands ("small", isolated groups of load(s) powered by generator sets independent of a grid or large utility for brief periods of time, and hopefully the load(s) don't vary by much over the period of separation. If the loads vary a lot during the period of separation and it's not possible for human operators to monitor the situation then DSLC's are probably a reasonable good idea for controlling load sharing.
 
From the description in your original post, it would seem that the "fighting" the two DG-sets exhibit is the result of both of them operating in Isochronous Speed Control mode. And, two governors in Isoch Speed Control mode (without some kind of external control method) will exhibit the exact behaviour you described, because BOTH want to be TOP DOG and control frequency, and in an AC power system that's just not possible (without some kind of Isoch Load Sharing scheme of some sort or other or something like DSLC's, maybe).

I don't want to become a DSLC "expert"--I don't particularly care for Woodward controllers or their manuals or GAP (which should be GIP--for Graphicaly Inadequate Program, because it's really inadequate (when you're used to something which is MUCH MORE graphical, which GAP is DEFINITELY NOT (you MUST use a paper manual to understand how the "blocks" or "tiles" work--and you have to have the exact version of the manual to do that, and even then I've been told by Woodward technical support that the written descriptions can be wrong.... so, that can make troubleshooting or even programming difficult at best, and downright impossible sometimes).

Anyway, I digress (a lot). It sounds like someone has to become a Woodward "expert" if the owner/operator of the units doesn't want to pay for Woodward or a Woodward-knowledgeable person to come to site to assist with fixing something that appears to have never been tested or worked properly during/after commissioning. It could be something simple, like contacts with the wrong sense. But, that's going to require some study and diligence on someone's part if the company won't pay for expertise. (And, in the end--they pay no matter what, because if it's one of their employees who has to study and learn (and maybe make a couple of mistakes along the way) they are paying the salary of that employee).

Please write back to let us know how you fare in resolving this problem!
 
Dear Sir,

Thanks for your valuable advice.

Yes, I managed to download soft copy of DSLC & 2301 manual trying my best to understand the contents and some passed field experience working with a LV Generator distributor. Unfortunately Could not obtain the software to access DSLC Setup and reading active/reactive power to confirm correct power flow.

The 2 units 11KV generators connected to 11KV common bus operating in Island mode during public utility power outage to support a Water Treatment Plant in same location, and a Raw Water Pumping Station at a remote location.

Due to limited manpower available for operating the generators and manual switching at various locations, intend to bring the system in fully automatic isochronous Island mode as to maintain constant frequency and load sharing.

I have once operated a unit in isochronous mode while incoming unit in droop mode with stable operating condition and constant frequency.

My concern of above operating mode is lack of manpower for full time monitoring the load condition of the generators, as load may variy from time to time, under certain process conditions of sudden load reduction, it may cause reversed power tripping.

Our next month load test is scheduled in 2 weeks time, if I have any update, will certainly shared in this forum.
 
CH Lee,

You've touched on one of the real problems with automatic load sharing. (Actually, I have a problem with the term "load sharing"--it means different things to different people, and it is often misused in these discussions of islanded operation.... But, I digress. Again.) You mentioned load loss when operating as an island. It's REALLY hard to program a "load sharing" scheme to account for most of the anticipated losses of load, much less all of the possibilities. And, it's the most common reason, in my opinion, for people not using these systems--because it doesn't work all the time.

The Isoch unit in a two unit island system (the other unit will be in Droop) can definitely trip on reverse power if there is a sudden large loss of load--and that means the sudden drop in load exceeds the amount of load being maintained by the Isoch unit at the time of the load loss. The Droop machine is just going to hum along as long as the frequency is relatively stable, but if the load loss is very large (more than the amount of load being supplied by the Isoch machine) AND the Droop characteristic won't allow the unit to reduce load as much as necessary as quickly as necessary then there are going to be problems. Either (most likely) reverse power or, in some cases, over-frequency trips.

Even if trained, experienced human beings are at the controls and can anticipate (if possible) large load losses it may not be fast enough to keep the lights burning.

In these cases, some special and unique protective relay schemes need to be developed and employed. Diesel gen-sets DO NOT like reverse power; it's very hard on them (the diesels; the generators don't really give a darn).

Many "load sharing" schemes try to use analog references or signal or have discrete signals which are too long in length (pulse) and don't allow for the fine-tuning necessary. Throw in some "tight" protective relay settings, and you're asking for trouble if the load can change quickly and by a large amount. And, really, most automation systems just don't have the "smarts" to react to some situations. They really need "fuzzy logic" or AI (Artificial Intelligence) to be able to learn from past events in order to survive future similar events. And, that's not included in the 2301 OR the DSLC.

This idea of load sharing is ... well, it's wonderful. Pie in the sky. Ideal. Utopian. Very desirable. But, the reality is quite often something very different.

You are doing well to understand the 2301's and the DSLC's, but you are also going to need to understand the protective relaying schemes and settings (sometimes, settings can be changed based on operating conditions; sometimes not). AND you also need to understand the nature of the load when operating as an island. Sometimes there are things which can be done to limit sudden large changes in load (such as not shutting off large motors when flow can be bypassed or shut off for a brief period of time until such time as normal operation can be restored).

There are just a LOT of variables and intangibles to take into account. And, sometimes it just has to be admitted: The best-laid plans just can't take into account every possible scenario and situation. Black-outs are going to happen from time to time, especially if the nature of the load when operating as an island is such that sudden large swings in load which just can only be reduced or anticipated to a very small degree, if at all/ever.

Best of luck! The Woodward manuals are not bad--but they are also written by engineers, which means that the things that were intuitively obvious to the writers should be intuitively obvious to the readers, too. And quite often they are not. Procedures--which seem to be written in a logical order--aren't. (Step 1; Step 2; Step 3; Step 4--oh and don't forget to THIS before Step 2; and so on). I always read and re-read and re-re-read these kinds of manuals. When I need a procedure to do some task, I look at what might be written--read it with a critical eye and mind--and write it down in the order which is most logical to me. I have even been known to call some manufacturers to verify the procedure in the manual could be a little better-written (and have been told, yes, that could be wrong or better).

But your task is large, because, as I say, you really need to understand many, many things NOT just the 2301's and the DSLC's--because they don't use fuzzy logic or AI and they don't know and in many cases can't be programmed to understand plant dynamics or even protective relay settings. It's all related--and while it would be great if the 2301's or the DSLC's (or some other kind of "power management system" or "load sharing system") could handle even the majority of situations, the likelihood of that happening is somewhere between slim and not.

Automation salespeople like to say their automation products are state of the art and they can do just about anything. But, while automation is getting better and better all the time--it's ain't there yet. And, it's got a long way to go. Especially in the area of islanded power system operation and control and protection. It's NOT JUST the generators and their prime movers--it's the entire plant, including protective relay settings.

Best of luck! You've a large task in front of you. You're on the right track. The challenge is to remember there are all kinds of things which all have to work together that AREN'T controlled or even monitored by the 2301's or the DSLC's.
 
CH Lee,

By the way, when I refer to a unit running in Isoch and another unit running in Droop--I am NOT including any kind of "load sharing" system or scheme. I'm referring to the simplest island system of two units--one in Isoch to control frequency and the other in Droop to provide some of the load so the Isoch unit doesn't have to do all the work.

Many "load-sharing" or "power management" systems have the gen-set prime movers running in Droop--or some kind of "Isoch load-sharing" which is just a detuned Isoch mode of control). Some are also called "Isoch standby." (There are all manner of terms loosely referring to the same scheme--the English language is so wonderful about that! NOT!) The thing to know about TRUE Isochronous Speed Control mode is this: It is NOT possible to manually change the load of the Isoch unit!!! The Isoch unit ONLY cares about frequency--period. As load changes, so will the frequency--so the Isoch unit responds to load changes by holding the frequency constant. Yes; the load does change on an Isoch unit, but IT'S NOT in response to any kind of load command or reference or signal. It's simply in response to the change in frequency resulting from the change in load. (If the load on the island increases, the frequency of the island will tend to decrease if nothing is done. The Isoch unit senses the change in FREQUENCY (caused by the change in load) and increases the energy flow-rate to the prime mover to keep the frequency at or very near nominal. Yes the load on the Isoch unit increases, but it's not directly because a load reference to the Isoch unit changed--it's because the increases load on the island initially caused the island frequency to decrease so the Isoch unit responded to keep frequency at or very near nominal.

If someone tries to manually change the load on an Iscoh unit with the RAISE or LOWER pushbuttons or HMI targets or bat-handle switches all that person is doing is changing the FREQUENCY reference--and NOT the load of the Isoch unit. The frequency of the island will change, but the load of the Isoch unit will not change (presuming the load on the island is stable when this is occurring).

The opposite occurs when the load on the island decreases--the Isoch unit senses an INCREASE in frequency and responds by decreasing the energy flow-rate into the prime mover to hold the system frequency at or very near the nominal frequency. Yes, the load on the Isoch unit decreases, but not because a load reference to the Isoch unit changed (remember--there ISN'T a load reference to the Isoch unit!), it's because the island system frequency changed when the island load changed.

Now, what happens to the Droop unit while all this is going on? Presuming the Isoch unit is controlling the frequency well, nothing. If it's set for 5 MW, regardless of what happens to the island load or the load on the Isoch unit the Droop unit is going to continue to accept 5 MW of the island load without changing. That's how Droop Speed Control "shares load"--that's what "load sharing" means, in the purest sense. Now if the island load is stable, and someone manually changes the load of the Droop machine that is the same as increasing or decreasing the load on the island--and that will initially cause a change in island frequency and that will be sensed by the Isoch unit and it will respond accordingly. So, if someone increases the load on the Droop unit the Isoch unit will respond by decreasing it's load by exactly the same amount. Or, if someone decreases the load on the Droop unit, the Isoch unit will respond by increasing it's load by exactly the same amount.

If someone wants to manually change the load on an Isoch unit on an island with two (or more) units synchronized to the island system, they have to do it by changing the load on one (or more) of the Droop units. And, that's what you're asking an automated system to do: Keep track of the loads on all the units, and try to keep the Isoch unit from tripping on reverse power, or reaching it's maximum power output, so that it can respond to load changes on the island. VERY complicated--ESPECIALLY if the load swings can be large and unanticipated.

Let's say the "load sharing" system is set to keep 1 MW on the Isoch unit at minimum, and 11 MW at maximum. And it is also set up to adjust the load on the Droop unit (of the same rating--as in your case) to keep the load of the Isoch unit at never less than 2 MW and never more than 10 MW. (These are theoretical limits/setpoints.) Further, let's say that the load on the island is at 6 MW, with the Droop unit carrying 4 MW and the Isoch unit carrying 2 MW. And, the load on the island drops by 3 MW (a LARGE upset in the island load). The Isoch unit is going to respond by decreasing the energy flow-rate into the Isoch prime mover because it sees the island frequency has increased suddenly and by an amount equal to 3 MW. BUT, it only has 2 MW of load on it. If the energy flow-rate causes the power output of the Isoch unit to go negative--which it will to try to keep the island frequency at rated--the Isoch unit will trip on reverse power. And, all this time, the Droop unit is trying to keep running at 4 MW, but when the Isoch unit trips it has to carry the ENTIRE load on the island--and without any signal to increase the energy flow-rate into the Droop unit's prime mover the frequency of the grid will drop, and may actually exceed the under-frequency trip setpoint.

The "load-sharing" system has to try to QUICKLY increase the load of the Droop unit when it senses a LARGE change in island grid frequency AND it knows the Isoch unit is already at or near minimum or will go below minimum, and also decrease the load of the Isoch unit to minimum. A very difficult balancing act for any system to do. And, if the load swings (positive or negative) can be bigger that in this example, well, the balancing act gets even more difficult.

Again, trying to anticipate most or all of the load swings on an island grid and trying to program a "load-sharing" or "power management" system to respond to all of them without tripping on under- or over-frequency, or reverse power--is difficult at best. Impossible at times.

I hope this helps. It's really not that difficult to learn or understand--as long as you know what the fundamentals of AC power generation are. And, how the 2301's and DSLC's are or can be programmed, and how the protective relays of the island system are set/configured. And, what the loading/unloading rates of the governors when operating in Droop are (3% I think you said at your site). I wish there was a YouTube video I could recommend, or a simulator which I could recommend, to try to understand even just the basics--which most people just don't grasp. They "think" [this] of [that] should happen, without really understanding how AC power generation really works. (Really, what they want is stable frequency AND load ALL THE TIME, regardless of what the rest of the island or grid is doing--and, well, that's just not possible. But, they "think" (believe) it should be possible and they demand it--without every trying to understand what the basic fundamentals are, because someone told them Droop Speed Control is very difficult to understand. And they don't understand this misused term "load sharing.")

Anyway, I digress. Yet again. Best of luck!

By the way, Droop Speed Control has been covered so many time on Control.com I think the website name should be changed to DroopSpeedControl.com.... Use the 'Search' feature at the top of any Control.com webpage to look at the very many previous threads on the topic. There's also a useful 'Similar Threads' feature at the bottom of every Control.com thread which can provide useful information (usually--it's not coming up with any Droop Speed Control threads for this thread.... But, then that wasn't your original question (even though it helps explain what you're up against with trying to make "load-sharing" work automatically at your site.)
 
Dear CSA,

Pardon me if this is not appropriately manner to address you.

Thanks for very detailed explanations of AC Generators paralleling issues.

Indeed initially I too doubt about load sharing capability in Isoch. Mode, but just trust the vendor must have done all research to come out with the solutions. In the case of DSLC, there is a loop to communicate between two units, believe the communication link enable load sharing between two generators, assuming both units have been probably set up and commissioner. Unfortunately I wasn't involved during commissioning phase and software is not available to view the set up and operating conditions of DSLC, the worst thing are those colleagues hired since commissioning phase were not involved in Generator commisssioning as well, no one can confirm whether the automatic synchronizing and load sharing system had been properly commissioned.

Totally agree with you that operating one unit in Isoch. Mode while the other in Droop mode to keep constant frequency posing operational problems with large load swing, that is the reason I am hesitant to adapt when having to operate in "unmanned" conditions.

Reason for me to trying of restoration to automatic synchronisation and load sharing is prompted by a previous project whereby we rented 2 units of temporary LV generators on duty/standby duty needed close transition change-over between 2 units, the operator who briefed the Plant operator for close transition change over demonstrated Isoch. synchronizing and evenly sharing the load for brief period, before unloading one unit for shutdown. Very impressive to notice perfect load sharing in Isoch mode.

Not sure what kind of PMS system deployed in that equipment, only noticed discrete PCB's of the control system have Japanese characters written on it.
 
I wish I had known more about the Isoch/Droop theory back when I was working offshore. We had 4 "identical" diesel gensets that we would manually synchronize together. I put "identical" in quotes because we knew that there was one engine (#2) that was "weaker" than the others. It would run hotter and we had to be careful when it was online.

The company that built the control system (Ross Hill Controls) did a lot of work in the oilfield, primarily on drilling rigs. Being a work boat, we had a LOT of very sudden and dramatic changes in electrical load on the bus, especially when we were maneuvering inshore or near a rig. I mean, we would go from 10% load up to 90% load and back again over the span of a few seconds. Repeatedly and often. The only times I can remember having a blackout are when there was a major catastrophic failure of one of the engines, like a turbocharger exploding, or water in the fuel, or a lubrication failure of some kind (sadly, exploding turbos were more common for us than the other issues, but that's a topic for a different day...). I don't know what their scheme was officially called, but each diesel had a Woodward governor that was basically a "dumb box" that received analog signals from the control module, which was a fairly complex box of analog circuits that I definitely did not have the expertise to understand. The 4 control modules were connected together and exchanged analog signals back and forth to balance the load between them. As long as we synchronized the generators correctly with the lowest numbered generator having a frequency setpoint slightly higher than the others, it "just worked". The load was shared between the generator engines smoothly and automatically.

When synchronizing a higher-numbered genset onto the bus, if we didn't reduce its frequency setpoint very soon after closing the breaker, the system would get unstable as it tried to take over as master. That's the only manual intervention I remember having to make: making sure the lowest-numbered genset had the highest frequency setpoint. That's how their master-slave circuitry was designed to work.
 
joseph_e2,

I'm NOT saying that "load-sharing" can't be made to work. I AM saying that most of the implementations I have had the (bad) fortune of working on didn't work very well. They were mostly custom-designed systems, many using PLCs, and most programmed and configured by people who just didn't really understand basic AC power generation fundamentals. And used by people who knew even less--but thought they knew everything.... Which was another part of the problem with these systems. Unless there's a good written description of the philosophy and intent of operation, it's everybody's guess as to how it should or does operate. And, then there's always the guy who say, in his best Texas twang, "Well, that's not how we did it on the last job!" (But he can't tell anyone any more than this is working like it did on his last assignment--which isn't worth anything when trying to troubleshoot this kind of a problem (or just about any other, either).)

And, I did write that in my experience properly configured and programmed Woodward load-sharing systems are probably one of the better systems--it's just that it takes experience and knowledge and a few mistakes and oopsies for people to gain the required experience and knowledge with these systems (along with a good bit of consultation with Woodward technical support--because what's written in the manuals IS NOT always how the equipment really works...!).

I will also say that many shipboard power management ("load-sharing") systems are a LOT better than most shoreside power plant systems. Not all of them, but many of them. Thought I think that knowledge and experience of the operators and their supervisors has a LOT to do with that. That and the very critical nature of keeping the "lights" and propulsion and steering working!!!
 
CSA: Absolutely agree with you. Wasn't trying to pick nits at all, just wishing I had access to that system and what I now know at the same time so I'd perhaps have better knowledge about it other than "That's the way we do it" in our best south Louisiana twang... ;)

I do remember poking around in some Woodward manuals and being left scratching my head in utter bewilderment.

The boat was built around 1982 with systems that were developed mostly in the 70s, so what I now know makes its stability even more impressive.
 
I wish I had known more about the Isoch/Droop theory back when I was working offshore. We had 4 "identical" diesel gensets that we would manually synchronize together. I put "identical" in quotes because we knew that there was one engine (#2) that was "weaker" than the others. It would run hotter and we had to be careful when it was online.

The company that built the control system (Ross Hill Controls) did a lot of work in the oilfield, primarily on drilling rigs. Being a work boat, we had a LOT of very sudden and dramatic changes in electrical load on the bus, especially when we were maneuvering inshore or near a rig. I mean, we would go from 10% load up to 90% load and back again over the span of a few seconds. Repeatedly and often. The only times I can remember having a blackout are when there was a major catastrophic failure of one of the engines, like a turbocharger exploding, or water in the fuel, or a lubrication failure of some kind (sadly, exploding turbos were more common for us than the other issues, but that's a topic for a different day...). I don't know what their scheme was officially called, but each diesel had a Woodward governor that was basically a "dumb box" that received analog signals from the control module, which was a fairly complex box of analog circuits that I definitely did not have the expertise to understand. The 4 control modules were connected together and exchanged analog signals back and forth to balance the load between them. As long as we synchronized the generators correctly with the lowest numbered generator having a frequency setpoint slightly higher than the others, it "just worked". The load was shared between the generator engines smoothly and automatically.

When synchronizing a higher-numbered genset onto the bus, if we didn't reduce its frequency setpoint very soon after closing the breaker, the system would get unstable as it tried to take over as master. That's the only manual intervention I remember having to make: making sure the lowest-numbered genset had the highest frequency setpoint. That's how their master-slave circuitry was designed to work.

Dear Joseph_e2,

Thanks for sharing your past operating experience.

I too suspect in our case the built-in power management system is not functioning properly, any minor different in speed setting between 2 gensets would result in load swing in Isoch mode, despite that I have checked all digit inputs for load sharing, breakers status are operating in correct order, the connection of LAN communication link in good order.

Honestly speaking, I have next to zero experience in automatic synchronizing and loading sharing or PMS, as when I worked for a generator distributor in late 70s, only involved in commissioning of manual system, majority in Island Mode, as at that time, such systems rarely deployed in this part of world.

In mid 80s thought the company awarded with 2*1MW automatic synchronizing & PMS system, the designer worked with discrete "SEG" devices, very unfortunate the project was shelfed due to the hotel owner encountered financial difficulty during financial crisis. Since then I discontinued to deal with generator.

Since recently I joined this company owns the system, I thought of taking this opportunity trying to read up relevant manuals to troubleshoot as to gain the experience of which I missed in earlier career.

I post the topic in the hope to tap the experience and knowledge gained from this forum.

I really appreciate you are willing to share your experience.

I must thank CSA too, who shared so much of in depth knowledge related to this topic.
 
joseph_e2,

I'm NOT saying that "load-sharing" can't be made to work. I AM saying that most of the implementations I have had the (bad) fortune of working on didn't work very well. They were mostly custom-designed systems, many using PLCs, and most programmed and configured by people who just didn't really understand basic AC power generation fundamentals. And used by people who knew even less--but thought they knew everything.... Which was another part of the problem with these systems. Unless there's a good written description of the philosophy and intent of operation, it's everybody's guess as to how it should or does operate. And, then there's always the guy who say, in his best Texas twang, "Well, that's not how we did it on the last job!" (But he can't tell anyone any more than this is working like it did on his last assignment--which isn't worth anything when trying to troubleshoot this kind of a problem (or just about any other, either).)

And, I did write that in my experience properly configured and programmed Woodward load-sharing systems are probably one of the better systems--it's just that it takes experience and knowledge and a few mistakes and oopsies for people to gain the required experience and knowledge with these systems (along with a good bit of consultation with Woodward technical support--because what's written in the manuals IS NOT always how the equipment really works...!).

I will also say that many shipboard power management ("load-sharing") systems are a LOT better than most shoreside power plant systems. Not all of them, but many of them. Thought I think that knowledge and experience of the operators and their supervisors has a LOT to do with that. That and the very critical nature of keeping the "lights" and propulsion and steering working!!!

Dear CSA,

I Salute you and admire you for your vast experience related to this topic, and your generosity to share your knowledge.

Apparently I have joined a right forum.
 
Dear Joseph_e2,

Thanks for sharing your past operating experience.

I too suspect in our case the built-in power management system is not functioning properly, any minor different in speed setting between 2 gensets would result in load swing in Isoch mode, despite that I have checked all digit inputs for load sharing, breakers status are operating in correct order, the connection of LAN communication link in good order.

Honestly speaking, I have next to zero experience in automatic synchronizing and loading sharing or PMS, as when I worked for a generator distributor in late 70s, only involved in commissioning of manual system, majority in Island Mode, as at that time, such systems rarely deployed in this part of world.

In mid 80s thought the company awarded with 2*1MW automatic synchronizing & PMS system, the designer worked with discrete "SEG" devices, very unfortunate the project was shelfed due to the hotel owner encountered financial difficulty during financial crisis. Since then I discontinued to deal with generator.

Since recently I joined this company owns the system, I thought of taking this opportunity trying to read up relevant manuals to troubleshoot as to gain the experience of which I missed in earlier career.

I post the topic in the hope to tap the experience and knowledge gained from this forum.

I really appreciate you are willing to share your experience.

I must thank CSA too, who shared so much of in depth knowledge related to this topic.
Just to add another point for clarity, the Woodward DSLC is a Digital Synchronizing and Load Control unit, capable to operate in Island Isoch Parallel Mode, and parallel with Grid.
 
We have 2 units of GE DG rated at 11KV 2.4MW operating as Island Mode when there is a power failure.

Both prime-movers are controlled by Woodward 2301 speed controller, its load sharing function disabled, speed setting/load controls signal biased from DSLC.

Each DG has a Woodward DSLC controller to perform automatic synchronization and load sharing.

Alternators are of LS, is modular AVR consists
of a digital trimmer/VAR/PF control module.

The system commissioned 20 years ago,.but noted no one ever attempt to operate the generators in parallel operation.

I have several attempts to perform automatic synchronizing unsucessfully, units always swing load from one to another upon closing incoming unit VCB and render to reversed power tripping in pretty short time, probably less than a m1/2 minute.

Operating in manual mode in Droop mode was stable and can easily manipulate active and reactive load.

Current practice in manual synchronizing and load sharing during monthly load test.

PT and CT polarity checked to be in good order.

Software of DSLC not available to view MW/Mvar in DSLC.

Company not willing to spend money engaging Woodward service personnel.

Seeking anyone's expertise advice to help in solving this problem.
Hi All,

Can you tell us why you are not able to find out and download MOOG windrive software...
I will review your thread and I'll come back with comments.. As I am still on vacations right now..

The best thing is that if you can provide a SLD or circuit diagram.. So I can review it and tell you what to do to get this plant operating smoother..

Cheers
James.
 
My mistake I was referring to ANother thread related to Moog IGV SERVO ISSUE..which Moog windrive is the software...

INDEED I wanted to ask about Woodward toolkit software.... On this thread/ issue..


Cheers
James
 
Hi All,

Can you tell us why you are not able to find out and download MOOG windrive software...
I will review your thread and I'll come back with comments.. As I am still on vacations right now..

The best thing is that if you can provide a SLD or circuit diagram.. So I can review it and tell you what to do to get this plant operating smoother..

Cheers
James.

Dear James,

Attached are SLD and DSLC interconection drawings, hope you can help.

How I wish I can get DSLC software to troubleshoot.

Thanking you in advance.

The file is too large to attach, will try again.
 
Hi All,

Can you tell us why you are not able to find out and download MOOG windrive software...
I will review your thread and I'll come back with comments.. As I am still on vacations right now..

The best thing is that if you can provide a SLD or circuit diagram.. So I can review it and tell you what to do to get this plant operating smoother..

Cheers
James.
Dear James,

Would you mine giving your email address?

Only way to get around of attaching large file size probably is by email.

Thanks.
 
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