JP2013238234A - Method for cooling internal combustion engine with range extender and device for cooling internal combustion engine with range extender - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for cooling an internal combustion engine with a range extender.SOLUTION: A method for cooling an internal combustion engine with a range extender, includes the following method steps: a step (S1) of detecting a cooling action variable and detecting an engine temperature and the engine torque of the internal combustion engine with at least the range extender in this case, a step (S2) of calculating a duty cycle from the detected cooling action variable in response to at least one regulated reference, and a step (S3) of controlling a first electric pump for operating a cooling circuit of the internal combustion engine with the range extender by the calculated duty cycle.

Description

  The present invention relates to a method for cooling an internal combustion engine with a range extender and an apparatus for cooling an internal combustion engine with a range extender.

  In a conventional automobile, the internal combustion engine is cooled by a mechanical main water pump that pumps the cooling medium through a cooling circuit and an electric engine fan that cools the cooling medium. The cooling of an internal combustion engine according to the prior art is described in the former East German Patent Application No. 265767.

  In many configurations, for example, an electric auxiliary water pump is also incorporated, which causes the cooling medium to circulate when the mechanical main water pump does not operate. This is the case, for example, during start / stop operation, in which case a warm cooling medium may be brought into the heat exchanger for heating the internal space.

  In a vehicle with a hybrid drive (ie with an internal combustion engine and an electric drive), the mechanical main water pump is replaced by an electric main water pump. This is necessary because cooling must be ensured even during electrical operation.

  In a vehicle with a purely electric drive, the mileage is related to the capacity of the battery. Since the capacity of the battery is limited, it is not possible to travel longer distances without charging the battery. Longer mileage can be achieved by incorporating a range extender (REX).

Former East German Patent Application Publication No. 265767

  It would be desirable to provide a cooling scheme for a range extender in an electric vehicle.

  According to the invention, the method for cooling an internal combustion engine with a range extender according to claim 1 comprises the following steps: detecting a cooling action variable, wherein at least the engine temperature and the engine torque of the internal combustion engine with a range extender are determined. Detecting a duty cycle from a cooling action variable detected according to at least one defined criterion; a first for operating a cooling circuit of the internal combustion engine with range extender according to the calculated duty cycle; A method for cooling an internal combustion engine with a range extender, the method comprising: controlling an electric pump.

  Furthermore, the present invention provides an apparatus for cooling an internal combustion engine with a range extender according to claim 5.

  Preferred embodiments are the subject of the respective claims.

  The main advantage of the invention described here is that cooling of the internal combustion engine with range extender is ensured in each operating state. Cooling occurs during normal operation, at high load conditions, and during critical sensor failures.

  Further features and advantages of embodiments of the present invention are apparent in the following detailed description of the invention, which will be described with reference to the accompanying drawings.

1 is a schematic flow diagram illustrating a method for controlling a cooling device of an internal combustion engine with a range extender according to an embodiment of the present invention. It is the schematic which shows the cooling device of the internal combustion engine with a range extender by embodiment of this invention.

  In the drawings, the same reference numerals denote the same members or members having the same function.

  FIG. 1 is a schematic diagram illustrating a method for controlling a cooling device for an internal combustion engine with a range extender according to an embodiment of the present invention. FIG. 2 illustrates a cooling device for an internal combustion engine with a range extender according to an embodiment of the present invention. FIG.

  In FIGS. 1 and 2, the symbols S1, S2 and S3 indicate successive method steps. Reference numeral 1 denotes an internal combustion engine with a range extender, reference numeral 2 denotes a first electric pump, and reference numeral 3 denotes a radiator. The cooling circuit K is further provided with a thermostat valve 4. Reference numeral 5 denotes a generator of the internal combustion engine 1 with a range extender, and an inverter attached to the generator is indicated by reference numeral 6. The second electric pump is indicated by reference numeral 7. The arrows indicate the flow direction of the cooling medium in the cooling circuit K.

  The core of the present invention is an operation method for controlling the first electric water pump 2 for cooling an internal combustion engine with a range extender of an electric vehicle. The coolant temperature detected by the temperature sensor in the cooling circuit is used as an important control variable. Cooling is performed by an electric water pump controlled via the range extender ECU.

  The function for controlling the first electric water pump 2 consists of three parts: control during normal operation, control during delay operation due to heat, and control during emergency operation.

  According to the embodiment of the present invention shown in FIG. 1, control during normal operation is performed in relation to the operating variables of the internal combustion engine 1 with range extender detected in the first step S1, that is, engine temperature and engine torque. . The mode of operation is preferably selected so that the first electric pump 2 operates faster at high engine temperatures and high loads. The duty cycle calculated in the second step S2 is multiplied by a correction factor related to the ambient temperature. Thereby, more intense cooling can be performed at a high outside air temperature. The value is then filtered by the PT1 element. By calculating the duty cycle, the first electric pump 2 can be continuously controlled in the third step S3.

  According to another advantageous embodiment of the invention, the transition to a delayed operation by heat is performed as the internal combustion engine 1 with range extender stops. Since cooling is indispensable even in this situation, the delay operation control device is activated when the switch-off of the internal combustion engine 1 with a range extender is detected. This delay motion controller calculates two important variables. First, a control duty cycle is calculated in relation to engine temperature. Second, the duration of the delay operation is calculated in relation to the engine and ambient temperature. This variable is detected at the time of transition to the delay operation. During the delay operation due to heat, the delay operation timer is attenuated, and the first electric pump 2 is controlled by the duty cycle. The delay action of the control device is extended until the heat delay action has ended and the internal combustion engine 1 with range extender no longer needs further cooling.

  According to another advantageous embodiment of the invention, an emergency operation is carried out if a temperature sensor error is detected. The electric water pump 2 is controlled by a fixed specified value. Thereby, the damage by the heat based on a sensor error can be prevented.

  According to the embodiment of the present invention shown in FIG. 2, the cooling device for an internal combustion engine with a range extender includes the following components: a cooling circuit K; a first electric pump 2, and a range extender is provided via the cooling circuit K. A cooling medium passing through the internal combustion engine 1 can be pumped, and depending on the configuration of the thermostat valve 4, the cooling medium is a small cooling circuit including at least the internal combustion engine 1 with a range extender, the first electric pump 2, and the thermostat valve 4, or Circulation is possible with a large cooling circuit including at least the internal combustion engine 1 with a range extender, the first electric pump 2, the thermostat valve 4, and the radiator 3.

  According to another advantageous embodiment of the invention shown in FIG. 2, the cooling device for an internal combustion engine with a range extender additionally comprises the following components: a cooling circuit K, the cooling medium being an internal combustion engine with a range extender 1 can be additionally circulated through the generator 5 and the inverter 6 through the radiator 3 having the second electric pump 7. It is preferable to control the thermostat valve 4 in relation to the cooling temperature and at least one other defined criterion.

  Although the present invention has been described based on preferred embodiments, the present invention is not limited to these embodiments. In particular, the materials and topologies described above are merely exemplary and are not limited to the described embodiments.

S1, S2, S3 Method step 1 Internal combustion engine with range extender 2 Electric pump 3 Radiator 4 Thermostat valve 5 Generator 6 Inverter 7 Electric pump K Cooling circuit

Claims (7)

In a method for cooling an internal combustion engine with a range extender, the following method steps:
Detecting a cooling action variable, in this case detecting at least the engine temperature and engine torque of the internal combustion engine (1) with range extender (S1);
Calculating a duty cycle from the detected cooling action variable according to at least one defined criterion (S2);
Cooling the internal combustion engine with a range extender comprising the step (S3) of controlling the first electric pump (2) for operating the cooling circuit (K) of the internal combustion engine with range extender (1) according to the calculated duty cycle How to do. The method of claim 1, wherein
A method of correcting the duty cycle by a correction factor related to the ambient temperature. The method of claim 1, wherein
It is additionally detected whether the internal combustion engine with range extender (1) is switched off, and if it is detected that the internal combustion engine with range extender (1) is switched off, at least one A duty cycle is calculated from the engine temperature of the internal combustion engine with range extender (1) according to defined criteria, and a delay operation is determined from the engine temperature and the ambient temperature of the internal combustion engine with range extender according to at least one defined criteria. A method of calculating a duration and controlling a first electric pump (2) for operating a cooling circuit (K) with a calculated duty cycle over a calculated delay operating time. The method of claim 1, wherein
If at least one cooling action variable is not detectable and / or is not accurately detectable, the duty cycle is not calculated, and the cooling circuit (K) for operating the cooling circuit (K) with a predetermined duty cycle is not calculated. Method of controlling 1 electric pump (2). An apparatus for cooling an internal combustion engine with a range extender comprising the following components:
A cooling circuit (K);
A first electric pump (2) that can be controlled according to claims 1 to 3,
The cooling medium passing through the internal combustion engine (1) with a range extender can be pumped via the cooling circuit (K), and the cooling medium is at least the internal combustion engine with a range extender according to the configuration of the thermostat valve (4). (1), a small cooling circuit comprising a first electric pump (2) and the thermostat valve (4), or at least an internal combustion engine 1 with a range extender, the first electric pump (2), the thermostat valve (4) and heat radiation A device for cooling an internal combustion engine with a range extender, which can be circulated in a large cooling circuit comprising a vessel (3). The apparatus of claim 5.
Further, the radiator comprising the following component: a cooling circuit K, wherein the cooling medium passing through the generator (5) and the inverter (6) of the internal combustion engine (1) with the range extender includes the second electric pump (7). Device that can additionally be circulated via (3). The device according to claim 5 or 6,
Apparatus in which the thermostat valve (4) is controllable in relation to the coolant temperature and at least one other defined criterion.

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