Electric Drive for 30ft River cruiser

[Groucho]

We are building a 30ft River cruiser, currently at the detail part of the design stage, where we have to define space and weight.

Drive is electric, with a separate generator for when the batteries are low or you need to extend the range.

We have been advised the motor should be in the order of 4kVA, but am finding it hard to get up to date advice on suitable motors and controllers.

I am sure it is possible to find an off the shelf motor + controller, but I am keen it is as efficient as possible so am struggling to know where to find advice.

Hoping someone can help

 

[gwboats]

I would recommend you try LMC in Honiton, Devon UK. Ask for Trevor.
I used his electric motors and controllers in designing the propulsion systems for both QRB 'Gloriana' and 'Boleh' yacht. (Google for more information).

Cheers,
Graham Westbrook
Naval Architect

 

[Groucho]

Graham,

Thank you, I have telephoned Trevor and will follow up.
I have also looked up QRB 'Gloriana' and 'Boleh' yacht and am very impressed, together with the other references on the LMC website.

I have known of the Lynch motor and Cedric Lynch for some time, being a high efficiency motor, so your advice has hit the mark.

Thank you.

 

[The Q]

Sorry for coming late to the party on this one, but My Elysian 27CC, Normally moored at Horning (Norfolk UK), is being converted to hybrid at the moment, based on the ideas in this blog .
http://worcesternb.blogspot.co.uk/

My generator is a Fischer Panda 4KW,
The boatyard recommended Electric motor is a 3 phase unit ( I haven't been to the yard and got the Full details yet it's only just arrived).

I met Cedric Many years ago, and Like his work, but I won't use LMC ( or was it their predecessors) because of what they did to Cedric, and his current partners (Agni Motors) are in India / Switzerland, which makes it difficult to use his system from him.
Also when you have to use a yard to do the work, I prefer to have them use something they are familiar with.

Because my mooring is the wrong side of a river and I don't have the lifting tackle to get the old BMC1500D out I'm using a yard to do the work for me.

Initially I'll be using a conventional 2V Cell battery ('cos I got them Cheap) but eventually will probably go over to a odyssey pack.

Oh a river cruiser in the terminology of the people I know is a traditional broads sailing boat / yacht , Not a motor cruiser, where as elsewhere that may not be the case could you confirm which you are having built? Just so those in the rest of the world are know what we are talking about.

It may also be useful to talk to John Williams in Stalham, and Rupert Latham who is also on the broads and are mines of useful information. although they are both looking at retirement so probably can't assist directly.

I will have four solar cells on the roof to keep it topped up and to cover for the many short journeys I make just across the river. I will fit a charger pack as soon as I get the boat back, so I can use the Broads Authority Electric posts .

 

[Groucho]

We are also in Horning, on the accessible side of the river, would you like to meet up to swap notes?

 

[The Q]

We are also in Horning, on the accessible side of the river, would you like to meet up to swap notes?

I would love to, but I am Busy for a couple of weeks catching up with things after Horning regatta week and a trip to Scotland a week before, so possible some day in a weekend September. Maybe prop up the New Inn bar or sit out by the river weather permitting.
we might be able to nip down the boat yard before / after to see how far they have got.

 

[fredrosse]

A simple relay system allows full use of a battery bank with half total voltage or full total voltage. The relay system is close to 100% efficient (no controller losses) in either configuration. Two DPDT relays gives; forward full voltage, forward half voltage, reverse full voltage, reverse half voltage.

I have used this with sucess driving a high efficiency PM motor, and having just full speed or half speed has been satisfactory for a relatively low speed displacement launch. PM motors in the 24V to 120V range, at 4 kW power are readily available. Full speed used for most outings of a few hours, and 1/2 speed with very significantly extended running duration and range.

 

[Oleboynow]

PLEASE SEARCH
Ric, he used to be here,he is expert
https://plus.google.com/117217540151330592995/posts