WO2010089791A2

WO2010089791A2 - Integrated control system and galvanic protection of the electric power suppliers for the marine applications

Info

Publication number: WO2010089791A2
Application number: PCT/IT2010/000029
Authority: WO
Inventors: Marco Monsurro'
Original assignee: Co.El.Mo S.R.L.
Priority date: 2009-02-05
Filing date: 2010-02-01
Publication date: 2010-08-12
Also published as: WO2010089791A3; EP2393709A2; EP2393709B1; ITNA20090003A1; IT1393721B1

Abstract

The patent proposes an integrated system for the control and galvanic protection of electric energy sources for marine applications. Said system makes it possible to have a galvanic isolation through an electric power converter (PFC) The management of the power flow among the electric sources, the load and batteries, is done by means of five suitably-controlled power converters (1-5).

Description

INTEGRATED CONTROL SYSTEM AND GALVANIC PROTECTION OF THE ELECTRIC POWER SUPPLIERS FOR TKE MARINE APPLICATIONS .

Boats have three different means to supply the utilities aboard them with electric power: a) through an on-shore power distribution switchboard (hereinafter called "shore") : b) through an electric energy accumulation system (batteries) : c) through a generating endothermic engine (hereinafter called "generating set") . Each of the above listed sources has a maximum power supply capacity and needs a specific command, control and distribution system.

It is the user who chooses the source to use. This choice is based on a subjective evaluation of the power necessary to be supplied to the utilities, which could probably involve a waste of energy resources compared to those which are actually needed .

Moreover, the very common use of the shore as the source to supply the utilities aboard the boat with power, ^' exposes the metal structures of the boats to damages caused by galvanic currents, typically present in ports. These currents take the shape of a single galvanic cell. On the one hand, the installation of a transformer on the boat could isolate the circuit aboard it from the circuit on-shore and reduces thus the corrosive effect of the above mentioned currents. Yet, on the other hand, such a transformer is not widely used because of its bulky dimensions and also because of the damage inflicted on the metal parts by the wet-saline environment on boats. This industrial invention patent proposes a system that unites both the management of electric energy sources for marine application and galvanic protection .

The system permits to have an intelligent power management, and guarantees the feeding of loads without any voltage interruption (no-break) as well as the galvanic protection of the boat structure.' The galvanic isolation is done by using electronic power converters (PFC) without the need to use a low frequency isolation transformer, as is the case in traditional systems.

This converter is made and shielded in a way to guarantee obtaining the same features as those of the low frequency transformer isolation. The advantage of using a high frequency transformer is the remarkable reduction of weight and dimensions compared to those of systems using low frequency isolation transformers.

Suitable measures have been taken to reduce capacitive couplings. The system principle is illustrated in fig. 1 of the system block diagram.

The main connection points of the system are: Cl) Connection to the generating set or to another energy source (photovoltaic, eolic, etc) . C2) Connection to the shore power grid.

C3) Connection to the ordinary utilities AC power supply . C4) Connection to the privileged utilities AC power supply (no break) .

C5) Connection to the starter batteries.

C6) Connection to the auxiliary batteries and the utilities DC line.

This system makes it possible to manage the power flow among electric sources, loads and batteries.

The management is done by means, of five suitably- controlled power converters: PFC, DC/DC (1), DC/DC (2), DC/DC (3) and DC/AC (4) .

Thanks to the Sl) , S2) and S5) contactors it is possible to choose the power supply mode, and thus connect the system to a generating set and/or to the shore power source. The electric power can be directly supplied to the boat AC ordinary utilities, or to the ordinary and privileged utilities, in accordance with the condition of the S3), S4) and S5) contactors.

Alternatively, this energy or part of it, can charge the batteries and feed the DC loads when it passes through the PFC, or it can be supplied to the AC loads through the inverters.

The possible functioning modes are described hereunder : A) Functioning mode: shore power supply (Fig 2)

This functioning mode is used when the batteries are being recharged.

The Sl) and S4) contactors are closed, while the

S2), S3) and S5) contactors are open. The active lines are Ll) L3) L4) L5) L6) L7) L8)

L9) LlO) LIl) L12) .

Part of the power supplied by the power grid is used to feed the ordinary loads, while the other part of it passes through the PFC. '

The PFC output power is then divided as follows: on the LlO) line to charge the batteries and feed the auxiliary battery DC loads. on the L5), L6) and L8) lines to feed the privileged AC loads.

B) Functioning mode: integrated shore power supply (Fig. 3) This functioning mode is active when the power required for the loads exceeds the limit set for the shore-supplied currents.

In this functioning mode, a part of the power required for the AC loads is sustained by the auxiliary batteries.

The Sl and S4 contactors are closed, while the S2) ,

S3 and S5 contactors are open.

The active lines are Ll) L3) L4) L5) L6) L7 ) L8)

L9) LlO) LIl) L12) L13) . Part of the shore power is used to feed the ordinary loads, while the other part of it passes through the

PFC.

The PFC output power is used to feed the AC privileged loads through the L5) L6) LB) lines. Part of the power necessary to feed the AC privileged loads is supplied by the batteries, and it passes through the DC/DC3 converter.

C) Functioning mode: limited shore power supply (Fig. 4)^' This mode is active if, during the previous phase, the voltage of the auxiliary battery gets lower than the fixed limit and the system is in the "sleep" mode, (the Unit cannot start) .

The non-privileged loads shall be disconnected. The Sl contactor is closed while the S2) , S3) , S4) and S5) contactors are open. The active lines are: Ll) L4) L5) L6) L8) L9) LlO) LIl) L12) L13) .

D) Functioning mode: power supplied by a generating set (Fig. 5) .

This functioning mode is active when: 1. the battery voltage in the shore power supply mode, gets lower than the fixed limit and the

"sleep" mode is not active (Unit enabled to start) .

2. the shore power does not exist and the generating set is started manually. The S2 and S4 contactors are closed, while the Sl,

S3 and S5 contactors are open.

The active lines are: L3) L4) L5) L6) L7) L8) L9)

LlO) LIl) L12) .

Part of the power supplied by the generating set is used to feed the ordinary loads and the other part passes through the PFC.

The PFC output power then goes on line LlO) to charge the batteries, if necessary, and to feed the auxiliary battery DC loads; and on the L5) , L6 and L8 lines to feed the privileged AC loads.

E) Functioning mode: integrated power supply by a generating set (Fig. 6)

This functioning mode is active when the power required for the loads exceeds the maximum power that can be supplied by the Unit.

In this mode, part of the power required for the AC loads is sustained by the auxiliary batteries. _

/ The S2 and S4 contactors are closed, while the S2,

S3 and-S5 contactors are open.

The active lines are: L2) L3) L4) L5) L6) L7) L8) L9) LlO) LIl) L12) L13) . Part of the power taken from the Unit is used to feed the ordinary loads and the other part passes through the PFC.

The PFC output power feeds the privileged AC loads through the L5, L6 and L8 lines. Part of the power necessary to feed the AC privileged loads is supplied by the batteries, and it passes through the DC/DC3 converter.

F) Functioning mode: generating set limited power supply This method is active if, during the previous phase, the voltage of the auxiliary battery gets lower than the fixed limit.

The non-privileged loads shall be opened.

The S2 contactor is closed, while the S2, S3, S4 and S5 contactors are open.

The active lines are: L2) L4) L5) L6) L8) L9) LlO)

LIl) L12) L13.

G) Functioning mode: with inverter (Fig. 8)

This mode is enabled in case of power supply shortage from the shore and from generating set.

Both the power grid and the generating set are disconnected.

The S3 contactor is closed, while the S2, S2, S4 and

S5 contactors are open. The active lines are: L6) L7) L8) L9) L13.

H) Functioning mode: using an inverter with limitation (Fig. 9) This mode is enabled if, during the inverter functioning mode, the battery voltage gets lower that the fixed limit.

The Sl), S2), S3), S4) and S5) contactors are open. The active lines are: L6) L8) L9) L13) .

Only the privileged loads and DC loads are supplied with power.

LlO) LIl) L12) L13.

I ) Functioning mode: combined power supply from the power grid and the generating set (Fig. 10)

This functioning mode refers to the condition in which the system is connected to a shore power grid but the required power is higher than the suppliable power (the maximum shore power threshold can be set by the user) .The generating set starts automatically, and it shall directly supply the L7) line, thanks to the closing of the S5 contactor.

Thus the Sl) and S5) contactors are closed, and the

S2, S3 and S4 contactors are open. The active lines are: Ll) L2) L3) L4) L5) L6) L7)

L8) L9) LlO) LIl) L12) .

The power supplied by the power grid passes through the PFC.

The PFC output power is then divided as follows: - on the LlO) line to charge the batteries and feed the auxiliary battery DC loads. on the L5) , Lβ) and L8) lines in order to feed the privileged AC loads.

Procedural and structural modifications can be applied to this prospect, within the limits of the same inventive concept which is defined by the following claims.

Claims

1. Integrated control system and galvanic protection of the electric power suppliers for the marine applications, characterized by the fact that it can, according to the connections that will be realized, manage the flows of the power between electrical sources, loads and batteries as this management is realized through five power converters opportunely controlled.

2. System, as for the same scope of the previewed claim, characterized by the fact that the galvanic isolation comes through a high frequency transformer.

3. System, as for the same scope of the previewed claims, characterized by the fact that it allows an operational modality with the batteries during the charge status according to the drawing fig.2.)

4. System, as for the same scope of the previewed claims, characterized by the fact that it allows an operational modality that will be active when the request of the load power exceeds the limits agreed from the current taken from the dock, according to drawing fig.3) .

5. System, as for the same scope of the previewed claims, characterized by the fact that it allows an operational modality that will be active if, during the previewed phase, the battery's tension of the services falls under a prefixed limit and the system is in "sleep" modality (engine interdict to the start) , all this is according to the drawing fig.4) .

6. System, as for the same scope of the previewed claims, characterized by the fact that it allows a modality in which the tension of the batteries falls under a prefixed limit and is not active "sleep" or, also, if the dock is not present and the engine is manually started, according to the drawing fig.5).

7. System, as for the same scope of the previewed claims, characterized by the fact that it allows an operational modality that will be active when the power required from the load exceed the maximum power that the engine can supply, according to the drawing fig.6) .

8. System, as for the same scope of the previewed claims, characterized by the fact that it allows an operational modality that will be active if during the previewed phase, the battery's tension of the services falls under the prefixed limit, according to the drawing fig.7) .

9. System, as for the same scope of the previewed claims, characterized by the fact that it allows an operational modality that will be active in case of a lack of feeding from the dock and also of the generating set, this according to the drawing fig.8)

10. System, as for the same scope of the previewed claims, characterized by the fact that it allows an operational modality that will be active if in inverter modality the battery's tension falls under the prefixed limit, according to the drawing fig.9) ^

11. System, as for the same scope of the previewed claims, characterized by the fact that it allows an operational modality that make reference to a condition in which the system is connected to a dock's board but the power required exceed the power that can be supplied, according to the drawing fig.10) .

All these points are mentioned in the enclosed drawings .