GB2548890A

GB2548890A - Method and apparatus for heating the passenger compartment of a passenger vehicle

Info

Publication number: GB2548890A
Application number: GB1605508.9A
Authority: GB
Inventors: John Allsop Dean
Original assignee: Clayton Vs Ltd
Current assignee: Clayton Vs Ltd
Priority date: 2016-03-31
Filing date: 2016-03-31
Publication date: 2017-10-04
Anticipated expiration: 2036-03-31
Also published as: GB2548890B

Abstract

the steps of: providing an infrared heat source, optionally more than one (20, 20a); providing a temperature sensor, optionally two (4, 40); providing a controller (46); providing an electrical power source (48); wherein the infrared heat source and the temperature sensor is positioned within the passenger compartment of the vehicle; the infrared heat source is in communication with the electrical power source; the controller is in communication with the infrared heat source and the controller is in communication with the temperature sensor; the method including the step of using the controller to monitor the temperature sensor, wherein the controller activates the infrared heat source when the controller detects a temperature recorded by the temperature sensor that is below a set point. The infrared heat sources could possibly be in the form of panels comprising a front casing, a rear casing, an infrared heating pad, an insulating pad, and a casing frame.

Description

Method and Apparatus for Heating the Passenger Compartment of a

Passenger Vehicle

TECHNICAL FIELD

The present invention relates to heating a passenger vehicle and particularly but not exclusively to a method of heating a passenger compartment of a vehicle, a passenger compartment of a vehicle, an infrared heat source for the passenger compartment of a vehicle, and a method of retrofitting an infrared heating system to a passenger compartment of a vehicle.

For the sake of reducing emissions from passenger vehicles, many new passenger vehicles are using all electric or hybrid powertrains and existing vehicles are being retrofitted with all electric or hybrid powertrains. For example all electric buses or all electric trains. Heating of the passenger compartments of the vehicles is often required.

BACKGROUND

It is well known to provide climate control systems in the cabin of a passenger vehicle. Controlling the climate in a passenger compartment, in particular the temperature of the passenger compartment is important for the comfort of the passengers of the vehicle. Historically, the heat source for heating the passenger compartment would come from the waste heat from an internal combustion engine of the vehicle. Increasingly there are more and more hybrid and electric vehicles that either do not have an internal combustion engine or it is not efficient to utilise the waste heat from the internal combustion engine. An alternative efficient method of heating a passenger compartment of a passenger vehicle is therefore required.

The present invention aims to provide an improved method related to the issues detailed above.

SUMMARY OF THE INVENTION

The invention utilises infrared heating panels arranged within the passenger compartment of a vehicle to heat the compartment.

According to a first aspect of the present invention there is provided a method of heating a passenger compartment of a vehicle, the method comprising the steps of: providing an infrared heat source; providing a temperature sensor; providing a controller; providing an electrical power source; wherein the infrared heat source and the temperature sensor are positioned within the passenger compartment of the vehicle; the infrared heat source is in communication with the electrical power source; the controller is in communication with the infrared heat source and the controller is in communication with the temperature sensor; the method including the step of using the controller to monitor the temperature sensor, wherein the controller activates the infrared heat source when the controller detects a temperature recorded by the temperature sensor that is below a set point.

Using a temperature sensor to record the temperature of the passenger compartment allows the infrared heat source to be activated only when the compartment temperature is below a set point temperature and therefore energy consumption is optimised.

The temperature sensor may be positioned at in an upper region of the passenger compartment of the vehicle.

Due to the buoyant nature heated air the positioning of the temperature sensor in the upper region of a vehicle means that the maximum temperature of the air will be recorded. A second temperature sensor may be provided in communication with the controller, wherein the second temperature sensor may be positioned in a lower region of the passenger compartment of the vehicle.

Due to the buoyant nature of heated air, the positioning of a second temperature sensor in the lower region of the passenger compartment enables the recording of the air temperature in what could conceivably be the coolest region of the passenger compartment. The controller and the two temperature sensors may be used to compare temperature readings.

The vehicle may be an electric vehicle or an electric hybrid vehicle and may have a high-voltage system and the electrical power source may be the vehicles high-voltage system.

As is well known in the art, hybrid and all electric vehicles have battery packs or cell packs which have a high voltage rating.

The method may include the step of continually monitoring a vehicle state-of-charge using the controller, the vehicle state-of-charge may be one of: high-voltage system charging; high-voltage system discharging; high-voltage system depleted.

Monitoring the state of charge of the vehicle means the energy drain on the vehicles battery pack can be optimised to manage the energy available to drive the vehicle.

The method may include the step of delaying the activation of the infrared heat source when the vehicle state-of-charge changes, preferably the duration of the delay may be twenty seconds.

Delaying the activation of the vehicle heating system at for example key-on ensures that the heating system is drawing no energy from the vehicle energy source, and therefore the maximum amount of energy is available to initialise other vehicle systems.

The infrared heat source may be an infrared heat panel.

Infrared panels are well known in the art and are efficient sources of heat. Infrared panels do not heat the air directly, the energy emitted heats the surfaces within a passenger compartment. The surfaces radiate heat into the air creating better thermal conditions for the passengers. Since the internal surfaces of the passenger compartment are heated rather than the air, variations in temperature inside a passenger compartment due to doors being opened and closed and air flow altering thought the passenger compartment have less effect on the overall temperature of the passenger compartment since the surfaces are still heated and radiate heat to quickly increase the passenger compartment temperature since the surfaces retain heat which may then be radiated.

The method may comprise the step of providing a voltage converter, preferably the method may include the step of reducing the electrical power source from a higher voltage to a lower voltage using the voltage converter, preferably the infrared heat source may operate on a 24 volt supply and preferably the high-voltage system may be a 550 volt battery.

It is advantageous for safety reasons to reduce the voltage of any system inside a vehicle to be as low as possible, operating the infrared heat source at a low voltage improves the passenger safety. Furthermore, operating the infra-red panels at a low voltage results in reduced energy consumption.

The infrared heat source may be positioned in an upper region within the passenger compartment, preferably a plurality of infrared heat sources may be provided. The infrared heat sources may be positioned on the ceiling of the passenger vehicle and for example may be positioned in the upper corner of the passenger compartment where a passenger compartment wall joins the passenger compartment ceiling.

The plurality of infrared heat sources may be dissimilar, and may be of various different physical form alternatively the plurality of infrared heat sources may have differing levels of energy output.

Providing more than one heat source allows customisation of the heating system for the specific requirements of the passenger compartment, certain areas of the compartment may require high levels of heat output and other areas may require less heat output from the infrared heat sources.

The method may include the step of deactivating at least one infrared heat source when the temperature sensor measures a temperature below the set point and the vehicle state-of-charge is high-voltage system depleted.

The method may include the step of recording a temperature reading every five minutes using the temperature sensor.

The method may include the step of comparing the temperature reading recorded by the temperature sensors using the controller.

According to a second aspect of the present invention there is provided a passenger compartment of a vehicle, the passenger compartment may have: at least one infrared heat source; at least one temperature sensor; a controller; an electrical power source; a voltage converter; wherein the at least one infrared heat source and the at least one temperature sensor may be positioned within a passenger compartment of the passenger vehicle; the at least one infrared heat source may be in wired communication with the voltage converter; the voltage converter may be in wired communication with the electrical power source; the controller may be in wired communication with the at least one infrared heat source and the controller may be in data communication with the at least one temperature sensor.

According to a further aspect of the present invention there is provided an infrared heat source for the passenger compartment of a vehicle, the heat source may comprise: a front casing; a rear casing; an infrared heating pad; an insulating pad; and a casing frame; wherein the front casing and rear casing are formed so as to encapsulate the infrared heating pad and insulating pad, and the casing frame receives a detent formed by abutting flanges of the front casing and rear casing such that the front casing and rear casing are held together and the infrared heating pad and insulating pad are encased.

According to yet another aspect of the present invention there is provided a method of fitting an infrared heating system to a passenger compartment of a vehicle, the method may comprise the steps of: providing an infrared heat source; providing a temperature sensor; providing a controller; providing an electrical power source; wherein the infrared heat source and the temperature sensor is positioned within the passenger compartment of the vehicle; the infrared heat source may be in communication with the electrical power source; the controller may be in communication with the infrared heat source and the controller may be in communication with the temperature sensor; the method including the step of using the controller to monitor the temperature sensor, wherein the controller activates the infrared heat source when the controller detects a temperature recorded by the temperature sensor that is below a set point. The infrared heating system may be fitted during manufacture of a vehicle or may be fitted to an existing or previously used vehicle.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure I shows a side profile of an exemplary passenger compartment of a vehicle;

Figure 2 shows an exploded view of an infrared heating panel according to an aspect of the invention;

Figure 3 shows a plan view of the infrared heating panel of Figure 2;

Figure 4 shows a side elevation of the infrared heating panel of Figure 2;

DETAILED DESCRIPTION

Preferred embodiments of the invention will now be described with reference to the accompanying drawings. It will be apparent to a person skilled in the art that the following descriptions of the embodiments are provided by way of example and illustration of the method and do not limit the scope of the invention as disclosed in the appended claims. In the embodiments shown, the method and apparatus is shown as being applied to a bus, as will be appreciated the method and apparatus are equally applicable tor trains, trams and other passenger vehicles.

Figure 1 shows a vehicle generally designated 10, with a plurality of infrared panels 20 affixed to the ceiling of the passenger compartment 12 of the vehicle 10. The infrared panels 20 are fixed to the interior ceiling of the passenger compartment using threaded fasteners. A temperature sensor 40 is also affixed to the ceiling of the passenger compartment 12 of the vehicle 10. A second temperature sensor 44 is affixed to the floor of the passenger compartment 12 of the vehicle 10.

Figure 2 shows an exploded view of an infrared panel 20. The infrared panel 20 is made of a front aluminium folded outer case 22, an infrared heating pad 24, an insulating material pad 26 and an aluminium folded rear casing 28. The front casing 22 and rear casing 28 encapsulate the infrared heating pad 24 and the insulating material 26 and are held together by extruded aluminium frame sections 30.

As is best seen in Figure 3, the infrared panel 20 has mounting tabs 32 positioned around the edge of the panel. The mounting tabs 32 enable easy mounting of the panel 20 to a surface. The panel 20 is fixed to a surface using threaded fasteners (not shown).

In order to heat the passenger compartment 12 of the vehicle 10, the interior air temperature of the passenger compartment 12 is recorded by a temperature sensor 40. The recorded temperature is compared to a predetermined target set point. If the recorded temperature is below the predetermined set point, the plurality of infrared panels 20 are activated. The activation of the infrared panels 10 causes the surfaces inside the passenger compartment 12 of the vehicle 10 to be heated by the infrared energy emitted by the infrared panels 20. The heating of the surfaces inside the passenger compartment 12 heat the air within the passenger compartment raising the overall temperature inside the passenger compartment. When there are passengers inside the passenger compartment 12, the energy emitted by the infrared panels acts to directly heat the passengers. The temperature sensor 40 continues to periodically record the air temperature inside the passenger compartment 12 of the vehicle 10.

In a specific example, the vehicle 10 is a bus with a passenger compartment 12 for up to fifty persons. The bus has an all-electric powertrain with motors providing the driving force and a 550v battery pack 48 supplying the energy to drive the motors. The passenger compartment 12 has an operators area 12a situated towards the front of the passenger compartment 12. The passenger compartment has an upper temperature sensor 40 positioned on the inside ceiling of the passenger compartment 12, and a low lower temperature sensor 44 positioned on the floor of the passenger compartment 12. The passenger compartment 12 has seven infrared panels 20, 20a positioned on the ceiling of the passenger compartment 12. The infrared panels 20, 20a are fixed to the ceiling panels of the passenger compartment 12 using threaded fasteners in the form of self-tapping panel screws (not shown). The six infrared panels 20 are all of the same energy output rating of 110 Watts and the infrared panel 20a situated in the operators area 12a of the passenger compartment 12 is of a lower energy output rating than each of the six infrared panels 20, in this case the lower energy rating being 90 Watts, however infrared panels of various energy output ratings may be positioned throughout the vehicle to most effectively heat the passenger compartment. The infrared panels 20, 20a are in wired communication with a step down transformer 45 which reduces the output voltage of battery pack 48 from 550v to 12v. The transformer 45 is positioned externally to the passenger compartment 12 on the vehicle 10. The infrared panels are in wireless data communication with a controller 46 which is situated externally of the passenger compartment 12 of the vehicle 10. The controller 46 interprets the temperature recordings made by each of the temperature sensors 44 and 40. If the recorded temperatures indicate that the passenger compartment 12 is at a temperature below a predetermined set point, the controller 46 sends a signal to the infrared panels 20, 20a to activate them if they are not already activated. Conversely, if the infrared panels 20, 20a are already activated and the temperature of the passenger compartment 12 is recorded as being above the predetermined set point, then the controller 46 sends a signal to the infrared panels 20, 20a to deactivate the infrared panels 20, 20a. To reduce the energy demand on the battery pack 48 of the vehicle 10 when starting the vehicle 10, the infrared panels 20 are deactivated for twenty seconds from the point at which the vehicle high voltage system is turned on.

If during use the vehicle battery pack 48 is low on charge the infrared panels 20, 20a will be disabled. Doing this prioritises providing energy for the essential vehicle functions such as powering the drive motors of the vehicle or vehicle lighting.

Table 1 below details various operating conditions of the vehicle 10 and the status of the infrared panels.

Table 1:

As can be seen when the high-voltage system is on charge, for example when the vehicle is in a vehicle storage compound overnight, the infrared panels can be activated. By activating the infrared panels to heat the vehicle whilst it is on charge means that as soon as the vehicle is turned on and driven using the energy from the battery pack 48, the passenger compartment 12 of the vehicle 10 is already heated. By preheating the cabin of the vehicle whilst on charge means that energy from the battery pack 48 is not used to initially heat the vehicle, rather the infra-red panels maintains the passenger compartment temperature. This reduces the energy demand on the vehicle battery pack 48 meaning that more energy is available to operate the vehicle for a longer duration.

The controller 46 interprets data from the multiple temperature sensors and compares the recorded temperatures with a predetermined set point or control map preinstalled on the controller. As will be appreciated the skilled person will select an appropriate number of infra-red panels for the specific application to achieve the best possible efficiency of heating of the passenger compartment 12.

In another embodiment of the present invention an additional system of infrared heating panels (not shown) are provided in the passenger compartment 12 of the vehicle 10 and act as a boost circuit. The additional infrared panel system is provided to increase or 'boost' the rate or at which the passenger compartment 12 of the vehicle 10 can be heated. Normally the additional system of infrared panels is only operated when the vehicle 10 is being charged. However, the additional infrared panel system may be activated periodically when the high-voltage system of the vehicle 10 is discharging. In this embodiment the boost circuit is operated in accordance with the parameters shown in Table 2 below, however, the person skilled in the art will realise that the parameters shown are merely exemplary and can be tailored for a specific purpose and environment.

Table 2:

Different embodiments of the present invention will have different numbers of temperature sensors and infrared panels. For example, the vehicle may be a train which would require a number of infrared panels in each of the passenger compartments and a number of temperature sensors in each of the passenger compartments.

Alternatively, the vehicle is a tram with a high voltage system which is constantly be charged as it is permanently connected to a mains source of electricity.

Claims

1. A method of heating a passenger compartment of a vehicle, the method comprising the steps of: providing an infrared heat source; providing a temperature sensor; providing a controller; providing an electrical power source; wherein the infrared heat source and the temperature sensor is positioned within the passenger compartment of the vehicle; the infrared heat source is in communication with the electrical power source; the controller is in communication with the infrared heat source and the controller is in communication with the temperature sensor; the method including the step of using the controller to monitor the temperature sensor, wherein the controller activates the infrared heat source when the controller detects a temperature recorded by the temperature sensor that is below a set point.

2. The method as defined in claim 1 wherein the temperature sensor is positioned at in an upper region of the passenger compartment of the vehicle.

3. The method as defined in claim 1 or claim 2 further comprising the step of providing a second temperature sensor in communication with the controller, wherein the second temperature sensor is positioned in a lower region of the passenger compartment of the vehicle.

4. The method as defined in any preceding claim wherein the vehicle is an electric vehicle or an electric hybrid vehicle having a high-voltage system and the electrical power source is the vehicles high-voltage system.

5. The method as defined in any preceding claim including the step of continually monitoring a vehicle state-of-charge using the controller.

6. The method as defined in claim 5 wherein the vehicle state-of-charge is one of: high-voltage system charging; high-voltage system discharging; high-voltage system depleted;

7. The method as defined in claim 6 including the step of delaying the activation of the infrared heat source when the vehicle state-of-charge changes.

8. The method as defined in claim 6 including the step of delaying the activation of the infrared heat source when the vehicle state-of-charge changes and the duration of the delay is twenty seconds.

9. The method as defined in any preceding claim wherein the infrared heat source is an infrared heat panel.

10. The method as defined in any preceding claim further comprising the step of providing a voltage converter.

11. The method as defined in claim 9 including the step of reducing the electrical power source from a higher voltage to a lower voltage using the voltage converter.

12. The method as defined in any preceding claim wherein the infrared heat source operates on a 24 volt supply.

13. The method as defined in claim 4 wherein the high-voltage system is a 550 volt system.

14. The method as defined in claim 14 wherein the high-voltage system is a battery.

15. The method as defined in any preceding claim wherein the infrared heat source is positioned at a relatively high level within the passenger compartment.

16. The method as defined in any preceding claim wherein a plurality of infrared heat sources are provided.

17. The method as defined in claim 16 wherein the plurality of infrared heat sources are dissimilar.

18. The method as defined in claim 16 wherein the plurality of infrared heat sources are of various different physical form.

19. The method as defined in claim 16 wherein the plurality of infrared heat sources have differing levels of energy output.

20. The method as defined in any preceding claim including the step of deactivating at least one infrared heat source when the temperature sensor measures a temperature below the set point and the vehicle state-of-charge is high-voltage system depleted.

21. The method as defined in any preceding claim wherein a further temperature sensor in communication with the controller is provided on the vehicle.

22. The method as defined in any preceding claim including the step of recording a temperature reading every five minutes using the temperature sensor.

23. The method as defined in any preceding claim including the step of comparing the temperature reading recorded by the temperature sensors using the controller.

24. A passenger compartment of a vehicle, the passenger compartment having: at least one infrared heat source; at least one temperature sensor; a controller; an electrical power source; a voltage converter; wherein the at least one infrared heat source and the at least one temperature sensor is positioned within a passenger compartment of the passenger vehicle; the at least one infrared heat source is in wired communication with the voltage converter; the voltage converter is in wired communication with the electrical power source; the controller is in wired communication with the at least one infrared heat source and the controller is in data communication with the at least one temperature sensor.

25. An infrared heat source for the passenger compartment of a vehicle, the heat source comprising; a front casing; a rear casing; an infrared heating pad; an insulating pad; and a casing frame; wherein the front casing and rear casing are formed so as to encapsulate the infrared heating pad and insulating pad, and the casing frame receives a detent formed by abutting flanges of the front casing and rear casing such that the front casing and rear casing are held together and the infrared heating pad and insulating pad are encased.

26. A method of retrofitting an infrared heating system to a passenger compartment of a vehicle, the method comprising the steps of: providing an infrared heat source; providing a temperature sensor; providing a controller; providing an electrical power source; wherein the infrared heat source and the temperature sensor is positioned within the passenger compartment of the vehicle; the infrared heat source is in communication with the electrical power source; the controller is in communication with the infrared heat source and the controller is in communication with the temperature sensor; the method including the step of using the controller to monitor the temperature sensor, wherein the controller activates the infrared heat source when the controller detects a temperature recorded by the temperature sensor that is below a set point.

27. A method of heating a passenger compartment of a vehicle constructed and/or arranged substantially as described herein with reference to and/or as illustrated in one or more of the accompanying figures.

28. A passenger vehicle constructed and/or arranged substantially as described herein with reference to and/or as illustrated in one or more of the accompanying figures.

29. An infrared heat source constructed and/or arranged substantially as described herein with reference to and/or as illustrated in one or more of the accompanying figures.