ENGINE-GENERATOR WITH AN ELECTRICAL COOLING FAN

Abstract

 An engine-generator comprises an internal combustion engine, a generator for providing electrical energy, a radiator and a fan for providing an air flow over the radiator. The fan is driven by an electromotor having a controllable angular speed. The generator further comprises a fan controller arranged to receive sensor data from sensors comprised by the generator unit for sensing at least one of engine status parameters and ambient parameters, the fan controller being further arranged to control the speed of the electromotor in response to the received sensor data at a controlled annular speed between a minimum speed and a maximum speed. An electromotor for powering a fan switching on and off has appeared to consume more power than a fan providing an air flow just enough for proper cooling. By controlling the angular speed of the fan, such more efficient use of available energy is provided.

Description

TECHNICAL FIELD

[0001] The various aspects and implementations thereof relate to a fan system for an engine-generator comprising an internal combustion engine, an electrical generator and a fan.

BACKGROUND

[0002] Combustion engines need to be cooled. They are usually either liquid cooled or air cooled. In both cases, an air flow is provided by means of a fan, which flows along a radiator or the engine, respectively. The fan is connected to the crankshaft of the engine or powered by a separate electromotor that switches on or off, triggered by a thermostat that senses the temperature of the engine.

SUMMARY

[0003] The fan consumes a significant amount of energy generated by the generator, up to 10%. Therefore, it is preferred to provide an efficient way of operating the fan system.

[0004] A first aspect provides an engine-generator comprising an internal combustion engine, an generator connected to the engine for converting mechanical energy to electrical energy, a radiator connected to the combustion engine via a coolant circuit and a fan for providing an air flow over the radiator. The fan comprises a rotor having blades and an electromotor having a controllable annular speed connected to the rotor. The generator further comprises a fan controller arranged to receive sensor data from sensors comprised by the generator unit for sensing at least one of engine status parameters and ambient parameters, the fan controller being further arranged to control the speed of the electromotor in response to the received sensor data at a controlled annular speed between a minimum speed and a maximum speed.

[0005] An electromotor for powering a fan switching on and off has appeared to consume more power than a fan providing an air flow just enough for proper cooling. By controlling the angular speed of the fan, such more efficient use of available energy is provided.

[0006] In an embodiment, the engine comprises at least one of a coolant temperature sensor for sensing coolant temperature and an inlet air temperature sensor for sensing inlet air temperature and the wherein engine is provided with an engine control unit for collecting data from the sensors and providing the collected data to the fan controller.

[0007] These parameters provide relevant input for controlling the fan.

[0008] An embodiment further comprises at least one of an ambient temperature sensor for sensing ambient temperature and an ambient humidity sensor for sensing humidity sensor, wherein the fan controller is arranged to receive collected data.

[0009] These parameters determine whether and how the engine may require any further cooling. If the outside temperature - or air temperature within a housing of the engine-generator - is relatively high, more air flow may be required as with lower ambient temperatures, with the same engine coolant temperature.

[0010] A second aspect provides a method of operating an electromotor of a for driving a fan comprising a rotor having blades comprised by an engine-generator unit comprising an internal combustion engine, an generator connected to the engine for converting mechanical energy to electrical energy, a radiator connected to the combustion engine via a coolant circuit, a fan for providing an air flow over the radiator and sensors for sensing at least one of engine status parameters and ambient parameters. The method comprises receiving sensor data and controlling annular speed of the electromotor at a controlled annular speed between a minimum speed and a maximum speed.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The various aspects and embodiments thereof will now be described in further detail in conjunction with drawings. In the drawings:

Figure 1: shows a schematic representation of an engine-generator; and

Figure 2: shows a flowchart of a procedure executed by the engine- generator.

DETAILED DESCRIPTION

[0012] Figure 1 shows a schematic view of an engine generator 100. The engine generator comprises an internal combustion engine 120, an electrical generator 110, a fan module 130 and a radiator 140 connected to the engine 120 via a coolant circuit 142. The coolant circuit 142 is shown comprising a single duct to enhance clarity of the figure; in practice, the coolant circuit 142 comprises a duct for transfer of coolant to the radiator 140 and a duct for transfer of coolant to the engine 120. The coolant circuit 142 may to that purpose comprise a pump. The coolant is preferably liquid.

[0013] The electrical generator 110 is provided with a power supply line 190 for providing high power electricity generated by the electrical generator 110. the power supply line 190 preferably provides three phase alternating current and may further comprise at least one of a ground line or a zero line.

[0014] The engine generator 100 further comprises a central processing unit 162 for controlling operation of the engine generator 100. The central processing unit 162 is connected to a storage module 164, a communication unit 166 and a screen 168. The storage module 164 is arranged for storing code for programming the central processing unit 162 to operate the engine generator 100 in accordance with the various aspects and examples discussed in this document. Furthermore, the storage module 164 may store data to be displayed on the screen 168 for informing user about the engine generator 100 and various components thereof. The communication unit 166 is arranged to send out data and receive data, for example for monitoring of the engine-generator 100 and/or for controlling the engine-generator 100.

[0015] The central processing unit 162 is connected to an engine control unit 122 comprised by the engine 120, to a fan control unit 138, a fan drive unit 136 and an environmental sensor module 180 via a bus system 150. The bus system 150 comprises a communication line and a bus controller and is preferably implemented as a CAN bus, though other bus systems may be used as well. The bus system 150 is preferably compatible with common automotive standards over which, among others, the engine control unit 122 is arranged to communicate as well. The fan control unit 138 is in Figure 1 shown as a separate component; in another implementation, functionality of the fan control unit may be comprised by the central processing unit 162. Alternatively, the various components are connected by means other than a bus system.

[0016] The fan module 130 comprises a hub 132 to which two, three, four, five, six, or more blades 134 are connected in equiangular positions. In another embodiment, the blades are connected at their outmost edges to an annular hub that is driven at the outer perimeter of the fan. The hub 132 is connected to the fan drive unit 136. The fan drive unit 136 is arranged to receive operating instructions via the bus system 150. The fan drive unit 136 is arranged to operate at multiple angular velocities between zero and a maximum speed. The multiple angular velocities may be discrete level or, alternatively, be set at any position between zero and maximum on a continuous scale.

[0017] The fan drive unit 136 comprises a bus communication unit 172, an instruction interpreter 174 and an electromotor 176. The bus communication unit 172 receives instructions, the instruction interpreter 174 translates the instructions to power to be provided to the electromotor 176 and the electromotor 176 drives the hub 132, thus rotating the blades 134. Rotation of the blades provides an air flow along the radiator 140, taking up thermal energy from the radiator 140. The coolant releases thermal energy, after which is may take up thermal energy from the engine 120, thus cooling the engine 120.

[0018] Figure 2 shows a first flowchart 200 depicting a procedure for operation of a fan system comprising the fan control unit 138 and the fan drive unit 136. The various parts of the first flowchart 200 are briefly summarised below and will subsequently be discussed in further detail. The procedure may be carried out by the fan control unit 138, the central processing unit 162, by another circuit or a combination thereof.

202

start procedure

204

start engine

206

run engine

208

obtain engine temperature

210

temperature at or above set point?

212

obtain engine data

214

obtain ambient data

216

temperature above set point?

218

determine first fan speed

220

run fan at first fan speed

222

temperature at of below set point?

224

determine second fan speed

226

run fan at second fan speed

228

switch off fan

[0019] The procedure starts in a terminator 202 and proceeds to step 204 at which the engine 120 is started; the engine is run in step 206. Subsequently, engine temperature is obtained at step 208. The engine temperature is preferably obtained by means of the engine control unit 122. Alternatively, the temperature and other parameters may be collected by means of separate sensors connected to any of the other controllers comprised by the engine-generator 100. The engine temperature may be obtained as temperature of the coolant in the engine or leaving the engine, but it ma also be obtained through other sensing means inside or outside the engine 120.

[0020] At step 210, it is determined whether the engine temperature is at or above a predetermined threshold. If this is not the case, the fan is switched off in step 228 - in case the fan would be running - and the procedure loops back to step 206.

[0021] If the engine temperature is at or above a predetermined threshold, the procedure continues to step 212, at which engine data other than engine temperature may be obtained. Engine parameters may include at least one of oil temperature, crank shaft torque, engine power, intercooler temperature, crank shaft angular speed, engine power, other parameters, or a combination thereof.

[0022] In step 214, data on environmental parameters are obtained via the environmental sensor module 180. Such environmental parameters may include at least one of inlet air temperature, outside temperature, temperature within a housing of the engine-generator 100, air humidity either inside or outside the housing, or a combination thereof.

[0023] In step 216, it is determined whether the engine temperature is at a set point. Such set point may be a specific temperature, but is may also be a temperature range preferred for the engine 120 is preferred to operate in. Such temperature or temperature range may be pre-det. Alternatively, it may depend on certain engine operating conditions like engine load - between minimum and maximum - or environmental conditions.

[0024] If the engine temperature is at the pre-determined set point, the procedure continues to step 224. If the temperature of the engine 120 is found to be higher than the set point, the procedure continues to step 218, at which a first fan speed is determined. The first fan speed is a speed at which sufficient air is provided to the radiator 140 for sufficiently cooling coolant to lower temperature of the engine 120, within an acceptable, optionally preset, amount of time. The first fan speed may be calculated using at least one of the parameters obtained, including outside air temperature and outside air humidity, as well as engine parameters.

[0025] At step 220, the electromotor 176 is driven to have the fan running at the first fan speed, by providing the appropriate instruction to the fan driving unit 136 over the bus system 150. The procedure proceeds to step 220, at which the temperature of the engine is checked to the set point. If the temperature is still above the set point, the process branches back to step 220. If the temperature is at or below the set point, the procedure continues to step 224.

[0026] In step 224, a second fan speed is calculated for driving the fan module 130 at a speed that is sufficient for providing an air flow for maintaining temperature of the engine 120 at the pre set temperature (point or range). This fan speed is determined using engine parameters and ambient parameters obtained earlier. Alternatively or additionally, parameters may be refreshed at this point. It is noted that the fan speed to maintain the temperature of the engine 120 depends on the load of the engine 120; while engine load increases while executing the depicted procedure, the required angular speed of the fan for providing a proper air flow to maintain temperature may change.

[0027] In step 226, the fan is run at the second speed by providing the bus communication unit 172, over the bus system 150, an instruction for running the electromotor 176 at the determined second fan speed. Subsequently, the procedure branches back to step 206. At the fan 130 module, data may be collected like fan temperature, fan angular speed, fan power, fan status, ambient temperature, other or a combination thereof. Values of such parameters may be sent back to the fan controller 138 and/or the central processing unit over the bus system 150 for further use, like optionally setting a desired fan speed or generating a warning message.

[0028] During the procedure, outside carrying out of the procedure, safety measures are applied. As one safety measure, temperatures may measured, including at least one of engine oil temperature, coolant temperature (leaving the engine or entering the engine) ambient temperature, fan temperature or engine temperature. If the temperature is too high or too low - beyond safety limits -, a warning message may be displayed on the screen 168. Such warning message is preferably pre-stored in the memory module 164..

[0029] In summary, the various aspects and implementations thereof relate to an engine-generator comprises an internal combustion engine, a generator for providing electrical energy, a radiator and a fan for providing an air flow over the radiator. The fan is driven by an electromotor having a controllable angular speed. The generator further comprises a fan controller arranged to receive sensor data from sensors comprised by the generator unit for sensing at least one of engine status parameters and ambient parameters, the fan controller being further arranged to control the speed of the electromotor in response to the received sensor data at a controlled annular speed between a minimum speed and a maximum speed. An electromotor for powering a fan switching on and off has appeared to consume more power than a fan providing an air flow just enough for proper cooling. By controlling the angular speed of the fan, such more efficient use of available energy is provided.

[0030] In the description above, it will be understood that when an element such as layer, region or substrate is referred to as being "on" or "onto" another element, the element is either directly on the other element, or intervening elements may also be present. Also, it will be understood that the values given in the description above, are given by way of example and that other values may be possible and/or may be strived for.

[0031] Furthermore, the invention may also be embodied with less components than provided in the embodiments described here, wherein one component carries out multiple functions. Just as well may the invention be embodied using more elements than depicted in the Figures, wherein functions carried out by one component in the embodiment provided are distributed over multiple components.

[0032] It is to be noted that the figures are only schematic representations of embodiments of the invention that are given by way of non-limiting examples. For the purpose of clarity and a concise description, features are described herein as part of the same or separate embodiments, however, it will be appreciated that the scope of the invention may include embodiments having combinations of all or some of the features described. The word 'comprising' does not exclude the presence of other features or steps than those listed in a claim. Furthermore, the words 'a' and 'an' shall not be construed as limited to 'only one', but instead are used to mean 'at least one', and do not exclude a plurality.

[0033] A person skilled in the art will readily appreciate that various parameters and values thereof disclosed in the description may be modified and that various embodiments disclosed and/or claimed may be combined without departing from the scope of the invention.

[0034] It is stipulated that the reference signs in the claims do not limit the scope of the claims, but are merely inserted to enhance the legibility of the claims.

Claims

1. Engine-generator comprising an internal combustion engine, an generator connected to the engine for converting mechanical energy to electrical energy, a radiator connected to the combustion engine via a coolant circuit and a fan for providing an air flow over the radiator;
the fan comprising a rotor having blades and an electromotor having a controllable annular speed connected to the rotor;
the generator further comprising a fan controller arranged to receive sensor data from sensors comprised by the generator unit for sensing at least one of engine status parameters and ambient parameters, the fan controller being further arranged to control the speed of the electromotor in response to the received sensor data at a controlled annular speed between a minimum speed and a maximum speed.

2. Engine-generator according to claim 1, wherein the engine comprises at least one of a coolant temperature sensor for sensing coolant temperature and an inlet air temperature sensor for sensing inlet air temperature and the wherein engine is provided with an engine control unit for collecting data from the sensors and providing the collected data to the fan controller.

3. Engine-generator according to any of the preceding claims, wherein the engine comprises an intercooler and further comprising at least one of an oil temperature sensor for sensing oil temperature and an intercooler temperature sensor for sensing intercooler temperature and the wherein engine is provided with an engine control unit for collecting data from the sensors and providing the collected data to the fan controller.

4. Engine-generator according to any of the preceding claims, further comprising at least one of an engine load sensor for sensing engine load and an engine annular speed sensor for sensing engine angular speed, wherein engine is provided with an engine control unit for collecting data from the sensors and providing the collected data to the fan controller.

5. Engine-generator according to any of the preceding claims, further comprising at least one of an ambient temperature sensor for sensing ambient temperature and an ambient humidity sensor for sensing humidity sensor, wherein the fan controller is arranged to receive collected data.

6. Engine-generator according to any of the preceding claims, wherein the fan controller is arranged to determine, based on received sensor data, an annular speed of the electromotor required to at least one of achieve and maintain a set point coolant temperature.

7. Engine-generator according to any of the preceding claims, wherein the fan comprises at least one of a fan annular speed sensor for sensing fan annular speed, a fan power sensor for sensing fan power, a fan temperature sensor for sensing fan temperature and an ambient temperature sensor for sensing ambient temperature, the sensor being arranged to provide the sensor data to the fan controller.

8. Engine-generator according to any of the preceding claims, further comprising a bus system arranged to communicate sensor data to the fan controller and to communicate fan power data comprising instructions to the fan enabling the fan to operate at an instructed annular speed.

9. Engine-generator according to any of the claims 2 to 8, wherein the engine control unit is connected to the bus system.

10. Engine-generator according to claim 8 or 9, wherein the bus system is a CAN bus.

11. Engine-generator according to any of the preceding claims, wherein the fan controller is further arranged to determine, based on the received sensor data, whether the fan can provide sufficient air for cooling the radiator to achieve a set point temperature and to issue a first signal if the fan cannot provide sufficient air for cooling the radiator to achieve the set point temperature.

12. Engine-generator according to any of the preceding claims, further comprising a display and a central control unit connected to the fan control unit for receiving data from the fan control unit and arranged to provide display data to the display to display data related to at least one of the sensor data and the fan status.

13. Engine-generator according to claim 12, further comprising a communication unit connected to the central control unit, the communication unit arranged to communicate at least one of sensor data status data to an entity remote to the generator unit.

14. Method of operating an electromotor of a for driving a fan comprising a rotor having blades comprised by an engine-generator unit comprising an internal combustion engine, an generator connected to the engine for converting mechanical energy to electrical energy, a radiator connected to the combustion engine via a coolant circuit, a fan for providing an air flow over the radiator and sensors for sensing at least one of engine status parameters and ambient parameters;
the method comprising receiving sensor data and controlling annular speed of the electromotor at a controlled annular speed between a minimum speed and a maximum speed.

15. Method according to claim 14, further comprising determining, based on received sensor data, an annular speed of the electromotor required to at least one of achieve and maintain a set point coolant temperature.

Drawing