Control system

Abstract

An electrical motor and energy management control system 100 for use in an electric powered marine vessel having at least one rechargeable battery 102 and at least one hydrogen fuel cell 104. The cont

Description

Field The present invention relates to an electric motor and energy management control system for use with an electric powered marine vessel. Background of Invention Combustion engines powered by fossil fuels generate carbon dioxide which is considered to be responsible for accelerating climate change and rising global average temperatures, concentration of carbon dioxide in Earth’s atmosphere has increased to over 400 parts per million. By way of comparison, in 1800, the concentration of carbon dioxide in the atmosphere was below 283 ppm. Diesel was once considered to be a more environmentally friendly fuel source than petrol as it produces less carbon dioxide. However, diesel produces considerably more NOx including nitrous oxide which is typically around 300 times more powerful greenhouse gas than carbon dioxide. Diesel also produces nitrous dioxide which is a major pollutant and contributes to smog. Governments are now making a move to ban the sale of further fossil fuel vehicles in order to reduce health risks from pollutant particulates and to meet national greenhouse gas targets. Marine vessels encounter unpredictable conditions (such as changing tides and wind directions) which can suddenly and unpredictably effect the energy usage. This sudden increase in energy could result in a non-fossil fuel powered engine being unable to navigate the vessel back to shore. There is therefore a need for a control system which is able to determine energy levels and to optimise the energy usage to enable a user to safely and effectively manoeuvre a marine vessel whilst reducing or eliminating the risk of becoming stranded. Summary of Invention According to a first aspect of the present invention, there is provided an electric motor and energy management control system for use with at least one rechargeable battery and at least one hydrogen fuel cell, in an electric powered marine vessel, the electric motor and energy management control system comprising: a processor configured in use to receive: a drive signal from a throttle unit in response to an operator command; a first signal from a first sensor connected to at least one rechargeable battery to provide an indication of battery level status; and a second signal from a second sensor connected to at least one hydrogen fuel cell to provide an indication of hydrogen fuel cell status; in which the processor is operative to derive an output drive signal from the drive signal and from the first and second signals, and in which the processor is configured in use to transmit the output drive signal to a motor controller; and a motor controller operative to supply a direct current source to at least one electric motor of an electric powered marine vessel, in which the motor controller is operative to receive the output drive signal from the processor, and operative in response to the output drive signal to selectively switch between providing a direct current (DC) supply from the at least one rechargeable battery and / or a direct current (DC) supply from the at least one hydrogen fuel cell in order to optimise an available DC source to supply the at least one electric motor. The system is preferably an electric powered marine vessel electric motor and energy management control system. The system preferably further comprises a charger connectable to an alternating current (AC) supply. The charger is preferably configured in use to charge the at least one rechargeable battery. The processor may be configured to provide a command signal to the charger. The charger is preferably operative, in response to a command signal from the processor, to charge the at least one rechargeable battery. The at least one electric motor is preferably a radial flux motor. The system may further comprise at least one pair of radial flux motors connectable or connected to an input shaft via a gearbox. The processor is preferably configured to control operation of the gearbox. The at least one radial flux motor is preferably configured to receive a DC supply from the motor controller in response to a signal from the throttle unit. The processor (for example the output drive signal) is preferably configured to determine the magnitude and instant of supplying DC to each radial flux motor. The system may further comprise a regenerative brake. The regenerative brake may be configured to convert kinetic energy from the at least one radial flux motor to an electric current. The regenerative brake is preferably operative to supply the electric current to the at least one hydrogen fuel cell. The system may further comprise a global positioning system (GPS) operative to receive a GPS signal indicative of a vessel location. The processor is preferably operative to receive a GPS signal to determine a course for the vessel. The system preferably further comprises a wireless receiver operative to receive a signal indicative of at least one maritime variable from the list including: air pressure, windspeed, wind direction, current and / or tide, or any combination thereof. The system is preferably provided in an hermetically sealed unit. The system preferably further comprises an alert mechanism operable to receive a warning signal received from at least one safety sensor. The at least one safety sensor is operable to determine one or more of: a gas leak, low coolant, motor temperature and / or battery temperature, or any combination thereof. The alert mechanism is operable to generate an alert signal (which may be audible and / or visual) to notify users of a gas leak, low coolant, motor and / or battery temperatures exceeding predetermined maximum temperatures. The system may further comprise a transmitter operable to transmit an alert signal to a remote recipient. The system preferably comprises a battery supply back up. The battery supply back up is preferably operable to provide a direct current to the at least one electric motor of the electric powered marine vessel. The motor controller is preferably operative to supply a direct current source from the battery supply back up in response to the output drive signal received from the processor. The output drive signal may indicate that the battery level status and hydrogen fuel cell status are below a predetermined minimum level. The system may comprise a plurality of rechargeable batteries connected together. The system may comprise a plurality of hydrogen fuel cells connected together. Optionally a battery supply back up is provided for navigational and / or radio communications equipment. Brief Description of the Figure Figure 1 is a schematic illustration of an electric motor and energy management control system for a marine vessel according to one embodiment of the present invention. Detailed Description of Preferred Embodiment of the Invention With reference to Figure 1, the electric motor and energy management control system 100 for use in an electric powered marine vessel (not shown) comprises a rechargeable battery 102 and a hydrogen fuel cell 104. It is to be understood that the system may comprise any suitable number of rechargeable batteries 102 and hydrogen fuel cells 104. The electric motor and energy management control system 100 further comprises a processor 106 configured in use to receive: a drive signal from a throttle unit 108 in response to an operator command; a first signal from a first sensor 110 connected to the rechargeable battery 102 to provide an indication of battery level status; and a second signal from a second sensor 112 connected to the hydrogen fuel cell 104 to provide an indication of hydrogen fuel cell status. The processor 106 is operative to derive an output drive signal from the drive signal and from the first and second signals. The processor 106 is configured in use to transmit the output drive signal to a motor controller 114. The motor controller 114 is operative to supply a direct current source to an electric motor 116 of the electric powered marine vessel. The electric motor is configured to receive a DC supply from the motor controller 114 in response to a signal, received by the processor 106, from the throttle unit 108. The electric motor is a radial flux motor; however it is to be understood that the electric motor may be any suitable type of motor. It is to be understood that the vessel may comprise a plurality of electric motors. For example, the vessel may comprise at least one pair of radial flux motors connectable or connected to an input shaft via a gearbox. The motor controller 114 is operative to receive the output drive signal from the processor 106, and operative in response to the output drive signal to selectively switch between providing a direct current (DC) supply from the rechargeable battery 102 and / or a direct current (DC) supply from the hydrogen fuel cell 104 in order to optimise an available DC source to supply the electric motor 116. The system 100 further comprises an AC battery charger 118 connectable to an alternating current (AC) supply. The charger 118 is configured in use to charge the at least one rechargeable battery 102. The processor 106 is configured to provide a command signal to the charger 118. The charger 118 is operative, in response to a command signal from the processor 106, to charge the rechargeable battery 102. In use, the processor 106 receives a first signal from the first sensor 110 connected to the rechargeable battery to provide an indication of battery level status, together with a second signal from a second sensor 112 connected to the hydrogen fuel cell 104 to provide an indication of hydrogen fuel cell status. Furthermore, the processor 106 receives a drive signal from the throttle unit 108 in response to an operator command. The processor 106 then produces an output drive signal (as a result of the received signals) which is transmitted to the motor controller 114 which is able to selectively switch between providing a DC current from the rechargeable battery 102 or from the hydrogen fuel cell 104 (or both) as a result of the drive signal. The processor 106 is able to determine the magnitude and instant of supplying DC to the motor. The system 100 is therefore able to optimise available DC sources to supply power to the electric motor 116 as a result of operator usage (throttle control) and the energy levels remaining in the battery or hydrogen fuel cell. The system provides a control system for optimising available supply of direct current from the most suitable energy source (battery or hydrogen fuel cell) as a direct result of energy levels as indicated by the first and second sensors 110, 112 and the operator usage as indicated by the drive signal from the throttle unit 108. The processor 106 may, when necessary, dependent on the first signal, emit a command signal to ensure that the charger supplies charge to the battery 102. The system further comprises a wireless receiver operative to receive a signal indicative of at least one maritime variable from the list including: air pressure, windspeed, wind direction, current and / or tide, or any combination thereof. The system further comprises an alert mechanism operable to receive a warning signal received from at least one safety sensor. The at least one safety sensor is operable to determine one or more of: a gas leak, low coolant, motor temperature and / or battery temperature, or any combination thereof. The alert mechanism is operable to generate an alert signal (which may be audible and / or visual) to notify users of a gas leak, low coolant, motor and / or battery temperatures exceeding predetermined maximum temperatures. The system may further comprise a transmitter operable to transmit an alert signal to a remote recipient. The system also comprises a global positioning system (GPS) operative to receive a GPS signal indicative of a vessel location. The processor 106 is operative to receive a GPS signal to determine a course for the vessel. The system may also comprise a user interface 120 enabling the user to set for example one or more of: predetermined minimum energy levels for the battery and / or fuel cell, set course of travel, speed settings, number of passengers etc. The system is therefore able to calculate the amount of energy available within the batter and hydrogen fuel cell, and the most suitable supply of DC energy required in order to navigate the vessel on an identified course to safety, for example back to shore. The system is responsive to external conditions such as for example windspeed, wind direction, current and / or tide. The system is operable to alter the supply of DC energy in response to these external conditions to optimise DC supply and to ensure safe and efficient transportation of the vessel. If necessary, the system may effect charging of the battery 102 to ensure that there is enough DC supply within the battery 102. The system may ensure that the DC supply is provided from the hydrogen fuel cell 104 whilst the battery 102 is being charged by the charger 118. The system can activate the alert mechanism to notify the operator that actions need to be taken in order to begin returning the vessel back to shore, preferably along an identified course (as determined for example by GPS), in order to ensure that there are sufficient levels within the battery and / or fuel cell to do so whilst taking into consideration factors such as wind and / or tides. As a result, the system of the present invention minimises, or preferably eliminates, the risk of the vessel becoming stranded as a result of lack of energy levels within the battery and / or hydrogen fuel cell as a result of the vessel using more energy due to sudden changes in tide and / or wind. The invention has been described by way of example only and it will be appreciated that variation may be made to the aforementioned embodiment without departing from the scope of protection as defined by the claims. 03 06 24

Claims

1. An electric motor and energy management control system for use with at least one rechargeable battery and at least one hydrogen fuel cell, in an electric powered marine vessel, including an electric motor and a motor controller is operative to supply a direct current source to the at least one electric motor of the electric powered marine vessel and in which the motor controller is operative to selectively switch between providing a direct current (DC) supply from the at least one rechargeable battery and / or a direct current (DC) supply from the at least one hydrogen fuel cell dependent on:a level of drive signal from a throttle unit in response to an operator command; anda first signal from a first sensor connected to at least one rechargeable battery to provide an indication of battery level status; anda second signal from a second sensor connected to at least one hydrogen fuel cell to provide an indication of hydrogen fuel cell status; anda global positioning system (GPS) that receives a GPS signal indicative of a vessel location, characterised in that a processor is operative to derive an output drive signal from the drive signal and from the first signal and the second signals and to calculate the amount of energy available and the processor processes the GPS signal, the first signal, the second signal and a signal indicative of at least one maritime variable from the list including: air pressure, windspeed, wind direction, current and / or tide, or any combination thereof, to determine an identified course and in order to ensure that there are sufficient energy levels within the battery and / or fuel cell, and selects the most suitable energy source (battery or hydrogen fuel cell) required in order to navigate the vessel on the identified course, for example ‘return to port’.

2. A system according to claim 1 whereby the processor is operative to determine available energy levels and energy spent to provide an indication of battery level status and to provide an indication of hydrogen fuel cell status.

3. A system according to claim 2 wherein an alert signal alarm is transmitted automatically via a transmitter to a remote recipient.

4. A system according to any preceding claim includes a charger which when connected to an alternating current (AC) supply, charges the rechargeable battery in response to a command signal from the processor.

5. A system according to any preceding claim wherein the at least one electric motor is a radial flux motor.

6. A system according to claim 5 wherein at least one pair of radial flux motors is connected to an input shaft via a gearbox.

7. A system according to claim 5 or 6 wherein the at least one radial flux motor receives a DC supply from the motor controller in response to a signal from the throttle unit.

8. A system according to claim 6 or 7 configured to determine the magnitude and instant of supplying DC to each radial flux motor.

9. A system according to any of claims 6 to 8 wherein a regenerative brake converts kinetic energy from the at least one radial flux motor to an electric current which powers the hydrogen fuel cell.

10. A system according to any preceding claim wherein the system is provided in an hermetically sealed unit.

11. A clear system according to claim 10 further comprises an alert when a warning signal is received from a safety sensor indicating a gas leak, low coolant, motor temperature and battery temperature.

13. A system according to any preceding claim wherein a battery supply back up is provided for navigational equipment.

14. A system according to any preceding claim wherein a battery supply back up is provided for radio communications equipment.

15. A system according to any preceding claim wherein a plurality of rechargeable batteries is connected together.

16. A system according to any preceding claim wherein a plurality of hydrogen fuel cells is connected together.

Images