JP5871745B2 - Fuel temperature control device - Google Patents

Description

  The present invention relates to a fuel temperature adjusting device that adjusts the temperature of fuel supplied to an engine.

  In order to evaluate the performance of an engine, it is necessary to operate the engine under various conditions and accurately measure the fuel consumption and the behavior of the engine under the various conditions. In order to perform this accurate measurement, the operating conditions of the engine must be accurately controlled, and the temperature of the fuel supplied to the engine must be accurately adjusted with respect to the target temperature.

  Patent Documents 1 and 2 disclose an apparatus for adjusting both the heating means for heating the fuel and the cooling means for cooling the fuel on the fuel supply path to the engine, and adjusting the temperature of the fuel by combining them. Yes.

Japanese Utility Model Publication No. 62-126559 JP-A-5-294788

  In the above-mentioned Patent Documents 1 and 2, since both the heating means and the cooling means are provided on the fuel supply path, the fuel can be heated and cooled freely. However, two temperature control means, heating and cooling, are required, and the apparatus becomes large correspondingly, resulting in an increase in cost.

  On the other hand, when only one of these two systems is provided, it is possible to avoid an increase in the size and cost of the apparatus as compared to providing two systems, but only one control of heating control or cooling control is possible. I can't do it. For this reason, there arises a problem that the fuel temperature cannot be adjusted over a wide range to perform measurement in a wide temperature range.

  Here, it is conceivable that the fuel temperature control is only one system and the heating control and the cooling control are switched. However, even in this case, there is a problem of how to control when it is necessary to perform temperature control in an unpredictable temperature range as to whether heating control or cooling control is necessary.

  In view of the above circumstances, an object of the present invention is to provide a fuel temperature control device capable of accurate control even with one system of temperature control.

The fuel temperature control apparatus of the present invention that achieves the above object provides:
A heat exchanger that adjusts the temperature of the fuel by heat exchange between the fuel and the liquid for heat exchange and sends the fuel toward the engine where the fuel is consumed;
A storage tank for storing the liquid and circulating the liquid to and from the heat exchanger;
A valve that is arranged on a circulation path between the storage tank and the heat exchanger of the liquid, is adjusted in opening degree under control, and adjusts a supply flow rate of the liquid to the heat exchanger;
A first temperature sensor for measuring the temperature of fuel delivered from the heat exchanger toward the engine;
A second temperature sensor for measuring the temperature of the liquid in the storage tank;
A controller that controls the opening of the valve so that the first temperature measurement value measured by the first temperature sensor approaches a first temperature control target value that is a fuel temperature control target value;
The control unit is
Based on the first temperature control target value and the first temperature measurement value, the first control value for valve opening control corresponding to the heating control for heating the fuel by the heat exchanger, and the heat exchanger A control value generating unit that generates both control values for the second control value for valve opening control corresponding to the cooling control for cooling the fuel;
Based on the first temperature control target value and the second temperature measurement value measured by the second temperature sensor, it is determined which of the heating control and cooling control should be performed, When the heating control is to be performed, the valve opening is adjusted based on the first control value. When the cooling control is to be performed, the valve opening is adjusted based on the second control value. And a valve adjusting unit that performs the above operation.

  Since the fuel temperature control apparatus of the present invention has a configuration for monitoring whether the heating control or the cooling control is to be performed and switching the heating control / cooling control adaptively, the temperature control system is Even with a single system, accurate control is possible.

Here, in the fuel temperature control device of the present invention,
The storage tank has been fed via a supply path different from the circulation path, and receives supply of liquid having a temperature lower than the first temperature control target value,
A second valve that is arranged on the supply path and is adjusted under control to adjust the supply flow rate to the liquid storage tank;
A heater for warming the liquid in the storage tank,
The controller controls the opening of the second valve and the heater so that the second temperature measurement value measured by the second temperature sensor approaches the second temperature control target value that is the liquid temperature control target value. It is preferable to further include a liquid temperature controller that controls both the amount of heating heat.

  Thus, by controlling the temperature of the liquid in the storage tank to be constant, the temperature of the fuel can be adjusted with higher accuracy.

  Here, in the case of the configuration including the liquid temperature control unit, the valve adjustment unit uses the second temperature control target value instead of the second temperature measurement value, and uses the first temperature control target value and the first temperature control target value. Based on the second temperature control target value, it may be determined which of the heating control and the cooling control should be performed.

  In the case of the configuration including the liquid temperature control unit, the second temperature measurement value substantially coincides with the second temperature control target value. Therefore, the second temperature control target value is set in place of the second temperature measurement value. It may be adopted.

Further, in the fuel temperature control device of the present invention, in the configuration including the liquid temperature control unit, the control unit further includes:
The second temperature control target value is set to an initial target value corresponding to the first temperature control target value, and the valve adjustment unit is configured to adjust the opening of the first valve to a predetermined fixed opening,
Until the first temperature measurement value approaches the first temperature control target value within a predetermined deviation, the second value is set by a value corresponding to the difference between the first temperature control target value and the first temperature measurement value. Repeat the adjustment of the temperature target value,
When the first temperature measurement value approaches the first temperature control target value within a predetermined deviation, the second temperature control target value is fixed to the second temperature control target value at that time, and the valve Liquid temperature target value calculation unit for causing the adjustment unit to switch the opening of the first valve from the fixed opening to the opening adjustment based on one of the first control value and the second control value It is preferable to provide.

  When the liquid temperature target value calculation unit described above is provided, the second temperature control target value, that is, the temperature control target value of the liquid in the storage tank, may be various conditions at that time, for example, the temperature of the fuel flowing into the heat exchanger, It is automatically set appropriately according to the temperature control target value (first temperature control target value) of the fuel flowing out from the heat exchanger.

  As described above, according to the present invention, accurate temperature control is possible regardless of one system.

It is a systematic diagram of the flow of the fuel and LLC (long life coolant: antifreeze) in the fuel temperature control apparatus of one embodiment. It is a block diagram which shows the structure of the control part of the fuel temperature control apparatus of this embodiment. It is a block diagram which shows the internal structure of a valve adjustment part. It is a flowchart which shows the calculation content in a constant temperature water temperature target value calculating part. It is the figure which showed the temperature stability of the supply fuel when T1 target value is set to 5 degreeC. It is the figure which showed the temperature stability of the supply fuel when T1 target value is set to 30 degreeC. It is the figure which showed the temperature stability of the supply fuel when T1 target value is set to 55 degreeC.

  Embodiments of the present invention will be described below.

  FIG. 1 is a system diagram of the flow of fuel and LLC (long life coolant; antifreeze) in the fuel temperature control apparatus of one embodiment.

  FIG. 1 shows a first heat exchanger 10, a second heat exchanger 20, and a third heat exchanger 30. FIG. 1 also shows a first valve 40 and a second valve 50, a first temperature sensor 60 and a second temperature sensor 70, a constant temperature water tank 80, a flow meter 90, and an engine 100. . The constant temperature water tank 80 is provided with a heater 81.

  The fuel is supplied from a fuel tank (not shown), passes through the first heat exchanger 10, the flow meter 90, and the second heat exchanger 20, and its temperature is measured by the first temperature sensor 60. Supplied to the engine 100. The engine 100 is a type of engine having a return fuel in which a part of the fuel supplied to the engine is returned, such as an electronic fuel injection engine. The returned fuel from the engine 100 returns to the inlet side of the second heat exchanger 20 through the third heat exchanger 30 and merges with new fuel that has passed through the first heat exchanger 10. And again passes through the second heat exchanger 20.

  Moreover, LLC is supplied to the constant temperature water tank 80 through the supply path L1 of LLC. A second valve 50 is disposed on the supply path L1. The second valve 50 is a variable opening type valve that receives an input of a control signal representing an opening from the outside and is controlled to an opening corresponding to the control signal. The LLC supplied to the constant temperature water tank 80 through the supply path L1 is an LLC sufficiently cooled to about 2 ° C. to 3 ° C., for example. The constant temperature water tank 80 is provided with a heater 81, and the LLC supplied into the constant temperature water tank 80 is heated to a desired temperature. Details will be described later. The temperature of the LLC in the constant temperature water tank 80 is measured by the second temperature sensor 70. The LLC adjusted to a desired temperature in the constant temperature water tank 80 circulates between each of the first heat exchanger 10, the second heat exchanger 20, and the third heat exchanger 30. Between the first heat exchanger 10 and the third heat exchanger 30, the LLC circulates at a constant flow rate. On the other hand, the first valve 40 is disposed on the circulation path L2 between the second heat exchanger 20 and circulates at a flow rate corresponding to the opening degree of the first valve 40. Similar to the second valve 50, the first valve 40 is a variable opening type valve that receives an input of a control signal representing the opening from the outside and is controlled to an opening corresponding to the control signal. . In the present embodiment, the first valve 40 is configured such that, of the LLC circulation path L2 between the constant temperature water tank 80 and the second heat exchanger 20, the LLC performs the second heat exchange from the constant temperature water tank 80. It is arranged on the outward path toward the vessel 20. However, the first valve 40 may be disposed on the return path where the LLC returns from the second heat exchanger 20 to the constant temperature water tank 80.

  The constant temperature water tank 80 is always filled with a certain amount of LLC, and the LLC exceeding the certain amount is drained from the drainage channel L3.

  The role of the fuel temperature adjusting device is to make the temperature of the fuel measured by the first temperature sensor 60 coincide with the target temperature.

  The temperature of the fuel supplied from the fuel tank (not shown) is adjusted by the first heat exchanger 10 so as to approach the target temperature. The first heat exchanger 10 is for coarse adjustment for reducing the burden of temperature adjustment of the second heat exchanger 20 and finely adjusting the temperature of the fuel with high accuracy by the second heat exchanger 20. is there.

  The fuel whose temperature has been roughly adjusted by the first heat exchanger 10 passes through the flow meter 90, and the flow rate of the fuel flowing therethrough is measured. This flow meter 90 is a positive displacement flow meter, and if the temperature differs greatly, an error occurs in the measured flow rate due to the volume change, but here the flow rate of the fuel in a temperature state almost approaching the target temperature is measured. The high-precision flowmeter side, that is, high-precision fuel consumption measurement is possible.

  The temperature of the fuel that has passed through the flow meter 90 is finely adjusted by the second heat exchanger 20 this time. This fine adjustment can be achieved by adjusting the opening of the first valve 40. Details will be described later. The temperature of the fuel that has passed through the second heat exchanger 20 is monitored by the first temperature sensor 60 and supplied to the engine 100.

  Since the return fuel from the engine 100 is warmed by the engine 100, the temperature thereof is roughly adjusted by the third heat exchanger 30, and the fuel whose temperature is roughly adjusted by the first heat exchanger 10 They are merged, finely adjusted again by the second heat exchanger 20, and supplied to the engine 100.

  Here, in terms of the temperature control of the fuel, the first heat exchanger 10 and the third heat exchanger 30 reduce the burden on the second heat exchanger 20 by the second heat exchanger 20. This is for carrying out highly accurate temperature control. Therefore, the first heat exchanger 10 and the third heat exchanger 30 are heat exchangers that do not necessarily need to be installed by adopting a larger capacity heat exchanger as the second heat exchanger 20. .

  That is, the second heat exchanger 20 is a heat exchanger corresponding to an example of a heat exchanger that is an essential requirement of the present invention. Moreover, the constant temperature water tank 80 shown in FIG. 1 respond | corresponds to an example of the storage tank said to this invention.

  FIG. 2 is a block diagram illustrating a configuration of a control unit of the fuel temperature adjusting device of the present embodiment.

  The overall role of the control unit 200 is to make the fuel temperature measurement value (T1 measurement value) obtained by the first temperature sensor 60 shown in FIG. 1 coincide with the fuel temperature control target value (T1 target value). In addition, the opening degree of the first valve 40 is adjusted.

  The control unit 200 includes a control value generation unit 210, a valve adjustment unit 220, a constant temperature water temperature control unit 230, and a constant temperature water temperature target value calculation unit 240.

  The control value generator 210 monitors the fuel temperature measurement value (T1 measurement value) by the first temperature sensor 60, receives the setting of the temperature control target value (T1 target value), and performs TID measurement value by PID control. The control value of the opening degree of the first valve is generated so that becomes close to the T1 target value.

  Here, for example, when the measured T1 value exceeds the T1 target value, and in the cooling control for cooling the fuel, the cooling capacity in the second heat exchanger 20 is increased by slightly increasing the opening of the first valve 40. Will be raised. On the other hand, even under the same condition that the measured T1 value exceeds the T1 target value, the second heat exchange is performed by slightly lowering the opening degree of the first valve 40 in the heating control for heating the fuel. The heating capacity in the vessel 20 will be lowered. That is, even if the relationship between the measured T1 value and the T1 target value is the same, whether the first valve 40 is moved further in the opening direction or the closing direction is different between the cooling control and the heating control. It will be.

  Therefore, in the control value generation unit 210, both the opening degree of the first valve 40 corresponding to the heating control and the opening degree of the first valve 40 corresponding to the cooling control are obtained. For example, when the measured T1 value exceeds the T1 target value, when the opening degree of the first valve 40 has been, for example, 52%, the control value for the heating control is the second heat exchanger 20. In order to lower the heating capacity slightly, a heating control value corresponding to the opening degree of 50% is generated so that the opening degree of the first valve 40 is reduced to, for example, 50%. Similarly, in the control value generation unit 210, the opening degree of the first valve 40 is set to 54%, for example, in order to slightly increase the cooling capacity in the second heat exchanger 20 as a control value for cooling control. A cooling control value corresponding to the opening degree of 54% is generated so as to increase.

  The heating control value and the cooling control value generated by the control value generation unit 210 are input to the valve adjustment unit 220.

  FIG. 3 is a block diagram showing an internal configuration of the valve adjustment unit 220.

  The valve adjustment unit 220 includes a comparison unit 221, a first switching unit 222, and a second switching unit 223.

  Both the heating control value and the cooling control value generated by the control value generation unit 210 and input to the valve adjustment unit 220 are input to the first switching unit 222.

The comparison unit 221 compares the value of the T1 target value with the temperature measurement value (T2 measurement value) of the LLC in the constant temperature water tank 80 measured by the second temperature sensor 70. And
When T1 target value> T2 measured value, it is determined that the cooling control should be performed, and a control signal S1 indicating the determination result is input to first switching unit 222. At this time, the first switching unit 222 controls the opening degree of the first valve 40 with the cooling control value of the heating control value and the cooling control value generated and input by the control value generating unit 210. A control signal (V1 opening) representing the control value is output as a control value. The opening degree of the first valve 40 is adjusted based on this control signal, and the flow rate of the LLC circulating between the constant temperature water tank 80 and the second heat exchanger 20 is adjusted. on the other hand,
When T1 target value <T2 measurement value, the comparison unit 221 determines that the heating control is to be performed, and a control signal S1 representing the determination result is input to the first switching unit 222. At this time, the first switching unit 222 uses the heating control value of the heating control value and the cooling control value as a control value for controlling the opening degree of the first valve 40, and a control signal (V1) representing the control value. Output).

  The heating control value or the cooling control value output from the first switching unit 222 in this manner is then input to the second switching unit 223. The second switching unit 223 also receives a V1 initial control value that is output from the constant temperature water temperature target value calculation unit 240 shown in FIG. 2 and that indicates a fixed opening of the valve (for example, 50% of the valve opening). The The second switching unit 223 is also switched by a fixed / control switching signal S2 output from the constant temperature water temperature target value calculation unit 240, and the valve switching unit 220 is switched by the first switching unit 222. Then, a control signal (V1 opening) representing the heating control value or the cooling control value or the V1 initial control value is output. The opening degree of the first valve 40 is adjusted based on this control signal, and the flow rate of the LLC circulating between the constant temperature water tank 80 and the second heat exchanger 20 is adjusted.

  Returning to the description of the control unit 200 shown in FIG.

  The constant temperature water temperature control unit 230 constituting the control unit 200 shown in FIG. 2 is responsible for the temperature control of the LLC in the constant temperature water tank 80.

  Here, the LLC temperature (T2 measurement value) in the constant temperature water tank 80 measured by the second temperature sensor 70 is input, and the LLC target temperature (T2 target value) in the constant temperature water tank 80 is input. Is set. In the present embodiment, this T2 target value is obtained by calculation in the constant temperature water temperature target value calculation unit 240. Details will be described later. In the constant temperature water temperature control unit 230, the opening degree of the second valve 50 (V2 opening degree) and the current value (heater current) flowing through the heater 81 are PID-controlled so that the measured T2 value matches the T2 target value. .

  In performing fuel temperature control using the fuel temperature control apparatus of the present embodiment, in the present embodiment, the constant temperature water temperature target value calculation unit 240 performs the constant temperature water tank 80 (see FIG. 1) as follows. The temperature control target value (T2 target value) of the constant temperature water is obtained.

  FIG. 4 is a flowchart showing the calculation contents for obtaining the T2 target value in the constant temperature water temperature target value calculation unit 240.

  Here, first, an initial flag indicating the initial control is turned on (step S11), and the second switching unit 223 shown in FIG. 3 is switched to the V1 initial control value side fixed at, for example, a valve opening of 50%. For this purpose, a fixed / control switching signal S2 is output. Then, for example, a control signal indicating 50% V1 opening degree is output from the valve adjusting unit 220, and the first valve 40 is adjusted to 50% opening degree (step S12).

  Further, in step S12, the temperature control target value (T2 target value) of the constant temperature water is set to a value corresponding to the fuel temperature control target value (T1 target value). In the example shown here, the same value as the T1 target value is set. Initially set.

  Thereafter, the process waits until the T2 measurement value, which is the temperature measurement value of the constant temperature water, stably matches the currently set T2 target value (step S13).

  Here, “consistently consistent” means that the T2 measurement value remains within a predetermined minute deviation for a predetermined time or more with respect to the T2 target value. When the T2 measurement value stably matches the T2 target value, the process waits until the T1 measurement value, which is the fuel temperature measurement value, is stabilized (step S14). That the T1 measurement value is stable means that the fluctuation range of the T1 measurement value remains within a predetermined fluctuation range for a predetermined time or more.

  When the T1 measurement value is stabilized, it is next determined whether or not the absolute value | T1 target value−T1 measurement value | of the difference between the T1 target value and the T1 measurement value is less than 0.1 ° C. as an example (step S15). ). Here, an example is given in which the T1 measurement value is adjusted within ± 0.1 ° C. with respect to the T1 target value.

  If it is determined in step S15 that the absolute value | T1 target value−T1 measured value | is not less than 0.1 ° C., the T2 target value is changed to (T1 target value−T1 measured value). ) Is added (step S16), and steps S13 to S15 are repeated.

  If it is determined in step S15 that the absolute value | T1 target value−T1 measured value | is less than 0.1, the process proceeds to step S17 to determine whether or not the initial flag is on. When the initial flag is on, the fixed / control switching signal for switching the second switching unit 223 to the first switching unit 222 side is switched to the valve adjustment unit 220 after the initial flag is turned off (step S18). S2 is output. Thereby, the 1st valve 40 is adjusted from the fixed opening degree (for example, opening degree 50%) to the opening degree according to the heating control value or cooling control value produced | generated by the control value production | generation part 210 (step S19).

  The current T2 target value is obtained through the steps up to here. Thereafter, the fuel consumption of the engine 100 (see FIG. 1) is measured. In the present embodiment, it is monitored whether or not the absolute value | T1 target value−T1 measured value | remains below 0.1 ° C. during the measurement (step S20). When the absolute value | T1 target value−T1 measured value | is outside the condition of less than 0.1 ° C., the T2 target value is changed to the T2 target value up to that time (T1 target value−T1 measured value) as in step S16. ) Is added (step S21), and the processing of each step after step S13 is repeated. However, in this case, since the initial flag is off, steps S18 and S19 are skipped, and the first valve 40 is continuously adjusted to the opening degree corresponding to the heating control value or the cooling control value.

  However, the process proceeds from step S20 to step S21 when the T1 measurement value slightly fluctuates and the absolute value | T1 target value−T1 measurement value | <0.1 ° C. is slightly deviated. If the target value is reset again, a new initial setting is started from step S11.

  In this embodiment, the constant temperature water temperature target value calculation unit 240 is provided and the T2 target value is obtained by calculation according to the flowchart shown in FIG. 4. However, the constant temperature water temperature target value calculation unit 240 is provided. It is not always necessary, and the T2 target value may be obtained by the operator performing the same adjustment as in the flowchart of FIG.

  In the present embodiment, as described above, since the heating control and the cooling control are switched according to the magnitudes of the T1 target value and the T2 measurement value, the fuel temperature adjustment system is one system. Heating control and cooling control are adaptively switched to perform accurate temperature control.

  In this embodiment, switching between the heating control and the cooling control is performed according to the magnitude of the T1 target value and the T2 measured value, but the T2 measured value is controlled so as to match the T2 target value. Therefore, even if the T2 target value is adopted instead of the T2 measurement value, accurate temperature control is similarly performed.

  Next, the temperature stability measurement result of the fuel supplied to the engine 100 in the embodiment shown in FIGS.

  FIG. 5 shows the temperature stability of the supplied fuel when the T1 target value is set to 5 ° C. and the allowable control temperature range is set to ± 0.1 ° C.

  At this time, the fuel temperature (T1 measurement value) supplied to the engine 100 needs to be within a range of 5 ° C. ± 0.1 ° C. Here, temperature fluctuations are observed when the fuel flow rate is changed stepwise as time [s] elapses. Specifically, the fuel flow rate is gradually increased from 10 [L / h] to 100 [L / h], and then gradually decreased from 100 [L / h] to 10 [L / h]. ing. As shown in FIG. 5, it can be seen that the fuel temperature is stable within 5 ° C. ± 0.1 ° C. even when the flow rate is changed in this way.

  FIG. 6 shows the temperature stability of the supplied fuel when the T1 target value is set to 30 ° C. and the allowable control temperature range is set to ± 0.2 ° C.

  At this time, the temperature of the fuel supplied to engine 100 needs to be controlled within an allowable temperature of 30 ° C. ± 0.2 ° C.

  Similar to the case of FIG. 5, even if the flow rate is changed stepwise, the fuel temperature is stably controlled within the allowable temperature range of 30 ° C. ± 0.2 ° C.

  FIG. 7 shows the temperature stability of the supplied fuel when the T1 target value is set to 55 ° C. and the allowable control temperature range is set to ± 0.3 ° C.

  At this time, the temperature of the fuel supplied to engine 100 needs to be controlled within an allowable temperature of 55 ° C. ± 0.3 ° C. Even if the fuel flow rate is changed stepwise from 10 [L / h] to 100 [L / h], the temperature of the fuel is stably controlled within the allowable temperature range of 55 ° C. ± 0.3 ° C.

DESCRIPTION OF SYMBOLS 10 1st heat exchanger 20 2nd heat exchanger 30 3rd heat exchanger 40 1st valve 50 2nd valve 60 1st temperature sensor 70 2nd temperature sensor 80 Constant temperature water tank 81 Heater 90 Flow meter 100 Engine 200 Control unit 210 Control value generation unit 220 Valve adjustment unit 221 Comparison unit 222 First switching unit 223 Second switching unit 230 Constant temperature water temperature control unit 240 Constant temperature water temperature target value calculation unit L1 Supply path L2 Circulation Road L3 Drainage channel

Claims (4)

A heat exchanger that adjusts the temperature of the fuel by heat exchange between the fuel and the liquid for heat exchange and sends the fuel toward the engine where the fuel is consumed;
A storage tank for storing the liquid and circulating the liquid with the heat exchanger;
A first valve that is disposed on a circulation path between the storage tank and the heat exchanger, adjusts an opening degree of the liquid under control, and adjusts a supply flow rate of the liquid to the heat exchanger. When,
A first temperature sensor for measuring the temperature of the fuel sent from the heat exchanger toward the engine;
A second temperature sensor for measuring the temperature of the liquid in the storage tank;
A control unit that controls the opening of the first valve so that the first temperature measurement value measured by the first temperature sensor approaches a first temperature control target value that is a temperature control target value of the fuel. And
The control unit is
Based on the first temperature control target value and the first temperature measurement value, a first control value for opening control of the valve corresponding to heating control for heating the fuel by the heat exchanger; A control value generator for generating both control values for the valve opening degree control corresponding to the cooling control for cooling the fuel by the heat exchanger;
Which of the heating control and the cooling control should be performed based on the first temperature control target value and the second temperature measurement value measured by the second temperature sensor And when the heating control is to be performed, the opening of the first valve is adjusted based on the first control value, and when the cooling control is to be performed, the second control is performed. And a valve adjusting unit that adjusts the opening of the first valve based on the control value. The storage tank has been fed via a supply path different from the circulation path, and receives the supply of the liquid at a temperature lower than the first temperature control target value,
A second valve that is arranged on the supply path and is adjusted under control to adjust the supply flow rate of the liquid to the storage tank;
A heater for warming the liquid in the storage tank,
The opening degree of the second valve so that the control unit approaches a second temperature control target value, which is a temperature control target value of the liquid, by the second temperature measurement value measured by the second temperature sensor. The fuel temperature control device according to claim 1, further comprising a liquid temperature control unit that controls both of the amount of heat generated by the heater and the amount of heat generated by the heater.   The valve adjustment unit uses the second temperature control target value instead of the second temperature measurement value, and based on the first temperature control target value and the second temperature control target value, 3. The fuel temperature adjusting device according to claim 2, wherein it is determined which of the heating control and the cooling control should be performed. The control unit further includes:
The second temperature control target value is set to an initial target value corresponding to the first temperature control target value, and the opening degree of the first valve is adjusted to a predetermined fixed opening degree in the valve adjustment unit. Let
A value corresponding to a difference between the first temperature control target value and the first temperature measurement value until the first temperature measurement value approaches a predetermined deviation from the first temperature control target value. The adjustment of the second target temperature value is repeated,
When the first temperature measurement value falls within the predetermined deviation from the first temperature control target value, the second temperature control target value is changed to the second temperature control target value at the time. In addition to fixing, the opening of the first valve is adjusted based on one of the first control value and the second control value from the fixed opening. 4. The fuel temperature adjustment device according to claim 2, further comprising a liquid temperature target value calculation unit for switching to adjustment.

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