JP2014153058A - Engine test device and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an engine test device and method capable of improving responsiveness of temperature control of an engine.SOLUTION: An engine test device 10 comprises: a heat exchanger 62 which adjusts a temperature of cooling water circulating to and from an engine 12; and a temperature control unit 70 which controls the temperature of the engine 12 by operating the heat exchanger 62. The temperature control unit 70 has: an operation amount map 76 showing a relation between a state of the engine 12 and an operation amount of the heat exchanger 62; a wasted time map showing wasted time from when a state of the engine 12 is changed until when the temperature of the engine 12 starts to change with respect to the state of the engine 12; and a time delay map showing a time delay variable for a temperature change of the engine 12 with respect to the state of the engine 12. The temperature control unit 70 performs control on the basis of these maps 76 to 78.

Description

  The present invention relates to an engine test apparatus and method, and more particularly to an engine test apparatus and method for performing a test by controlling the temperature of the engine.

  An engine bench is known as an engine test apparatus for testing whether a test engine developed and manufactured has a predetermined performance. The engine bench is a device for connecting a dynamometer to the output shaft of the engine and performing a test while controlling the load of the engine with the dynamometer, and measures the engine speed, torque, combustion gas, and the like.

  In such an engine bench, in recent years, it has been required to accurately control the temperature of the engine during the test. Therefore, a heat exchanger is provided on the engine bench, and the test is performed while circulating cooling water whose temperature is controlled by the heat exchanger to the engine (see, for example, Patent Document 1).

  PID control is generally performed as a temperature control method using a heat exchanger. That is, when the temperature of the cooling water deviates from the target temperature, the valve of the heat exchanger is adjusted to perform control so that the cooling water reaches the target temperature. However, since PID control is feedback control, there is a problem that it takes time until the temperature is stabilized at a constant temperature. In the engine test, many tests are performed in various environments with different conditions such as engine speed and torque value. Therefore, if one test time is long, the entire test time becomes very long. A problem occurs.

  Thus, it has been proposed to calculate the amount of heat generated by the engine and the amount of cooling of the heat exchanger by calculation, and to control the heat exchanger based on the calculated value. According to this method, since the temperature of the cooling water is quickly adjusted according to the state of the engine, the responsiveness of engine temperature control can be improved. However, the engine under development differs in shape and structure from engine to engine, and it is difficult to calculate accurately, so the responsiveness of temperature control cannot be improved reliably.

  As another method for improving the responsiveness of temperature control, a temperature control method using a map can be considered. In this method, an appropriate operation amount (usually the valve opening of the heat exchanger) is obtained in advance in various environments, and an operation amount map is created. During the test, an appropriate operation amount is determined from this operation amount map. Thus, feedforward control is performed.

JP2011-127904A

  However, in practice, even if the temperature control is performed using the manipulated variable map, there is a limit in improving the responsiveness, and there is a problem that appropriate temperature control is difficult. As the main factor, for example, it is conceivable that the start timing is deviated between the heat generated by the engine and the cooling by the heat exchanger, or the temperature change rate is different between the two. Therefore, in the conventional test apparatus, the responsiveness could not be sufficiently improved even if the temperature control is performed by the operation amount map.

  The present invention has been made in view of such circumstances, and an object thereof is to provide an engine test apparatus and method capable of improving the responsiveness of engine temperature control.

  In order to achieve the above-mentioned object, the invention according to claim 1 controls the temperature of the engine by operating the heat exchanger and a heat exchanger that adjusts the temperature of cooling water circulating between the engine and the engine. And a temperature control device that controls to a target value. The temperature control device includes an operation amount map in which an operation amount of the heat exchanger is indicated with respect to a state of the engine, The dead time map from the change in state until the engine temperature starts to change shows the dead time map shown for the engine state, and the time delay variable related to the engine temperature change becomes the engine state. A time delay map shown for the engine, and controlling the engine temperature based on the manipulated variable map, the dead time map, and the time delay map. To provide an engine testing apparatus according to.

  According to the present invention, since not only the operation amount map but also the dead time map and the time delay map are provided, an error that occurs when control is performed only by the operation amount of the operation amount map can be eliminated. Responsiveness and accuracy can be reliably increased. Further, according to the present invention, since the same parameter (engine state) is used in the operation amount map, the dead time map, and the time delay map, all maps can be created at once. The time delay variable is a value for adjusting the operation amount by multiplying the operation amount by 1 / (1 + τs) when the variable is τ.

  According to a second aspect of the present invention, in the first aspect of the invention, the temperature control device performs a pre-test by feedback control under a plurality of conditions by changing the state of the engine. A time map and the time delay map are created. According to the present invention, since a pre-test is performed using an engine that is actually used for the test and a map is created based on the data, an appropriate map can be created for each engine. That is, there is no error for each type of engine as in the case of control with an arithmetic expression, and accurate temperature control can be performed.

  According to a third aspect of the present invention, there is provided an engine test method for testing the engine in a state in which the temperature of the engine is controlled by a heat exchanger in order to achieve the object. A test by feedback control under conditions, a pre-test step for obtaining data on the operation amount of the heat exchanger and the temperature of the engine, and the operation amount of the heat exchanger is determined based on the obtained data. A manipulated variable map shown for the state, a dead time map shown for the engine state after the engine state changes, and a dead time until the engine temperature starts to change, A map creation step for creating a time delay map in which time delay variables related to engine temperature changes are indicated for said engine state; The engine state is input to the manipulated variable map, the dead time map, and the time delay map, and the heat exchanger is operated based on the determined manipulated variable, the dead time, and the time delay variable. And a main test step for testing the engine.

  According to the present invention, a pre-test is performed using an actual engine to be tested, an operation amount map, a dead time map, and a time delay map are created, and the main test is performed while controlling the temperature of the engine based on these maps. I do. Therefore, since temperature control is performed based on actual engine data, the engine temperature can be controlled quickly and accurately.

  According to a fourth aspect of the present invention, in the invention of the third aspect, the map creating step simulates an engine temperature using a model simulating the engine test device, and the simulation result and the pre-test step are obtained. The time delay variable is determined by comparing the engine temperature change data.

  According to the load cell of the present invention, not only the operation amount map, but also a dead time map and a time delay map are provided, so that an error in controlling with the operation amount of the operation amount map can be eliminated, and the engine temperature control Responsiveness and accuracy can be improved with certainty. Further, according to the present invention, since the same parameter (engine state) is used for all maps, both maps can be created at once.

Schematic configuration diagram of the engine test apparatus of the present embodiment Model illustration Block diagram showing the configuration of the temperature controller Flow chart in the engine test apparatus of the present embodiment Diagram explaining map creation The figure which shows an example of the operation amount map Figure showing an example of a dead time map Figure showing an example of the delay time map The figure explaining the effect of this Embodiment

Hereinafter, preferred embodiments of an engine test apparatus according to the present invention will be described with reference to the accompanying drawings. FIG. 1 is a schematic configuration diagram of an engine test apparatus according to the present embodiment.
The engine test apparatus 10 shown in the figure is an apparatus for measuring and evaluating the performance of the engine 12 to be tested, and mainly includes a dynamometer 20, an engine / dynamo control unit 30, an operation management unit 40, a cooling device 60, and temperature control. The apparatus 70 is configured.

  The engine 12 is fixed to the gantry 14 via a holding mechanism. A combustion chamber (not shown) is provided inside the engine 12, air sucked from an intake pipe (not shown) is supplied to the combustion chamber, burned, and then exhausted from an exhaust pipe (not shown). . The intake pipe is provided with a throttle (not shown), and the amount of air inflow is adjusted by the throttle. On the other hand, the exhaust pipe is provided with a catalyst mounting portion (not shown), and the exhaust gas is purified by the catalyst mounted on the catalyst mounting portion.

  The output shaft of the engine 12 is connected to the dynamometer 20 via the shaft 22. The shaft 22 is configured by connecting a plurality of shaft members such as a main shaft, and a universal joint is interposed in the connecting portion. Further, an intermediate bearing 24 is provided between the engine 12 and the dynamometer 20, and the shaft 22 is rotatably supported by the intermediate bearing 24. A torque meter 26 is attached to the shaft 22, and the torque of the shaft 22 is measured by the torque meter 26. In the present embodiment, the torque is measured by the torque meter 26. However, the present invention is not limited to this. For example, the torque may be detected from the output of the dynamometer 20. In addition, a clutch, a transmission, various connecting means, and the like may be inserted according to the purpose, and further, the state of the engine 12 other than the torque, for example, the temperature of the exhaust gas may be measured.

  The dynamometer 20 is a device that applies a predetermined load torque to the engine 12, and can set the load torque by varying the current and voltage. As the dynamometer 20, it is preferable to use a low inertia dynamometer. By using a low inertia dynamometer, a stable output corresponding to a sudden change in the rotational speed from low speed rotation to high speed rotation can be obtained.

  The engine 12 and the dynamometer 20 described above are connected to an engine / dynamo control unit 30. The engine / dynamo control unit 30 has a function of controlling the drive of the engine 12 by giving control parameters such as a throttle opening and an ignition advance angle to the engine 12. This engine drive control function is usually realized by an ECU or an engine control circuit in which a bypass circuit is added to the ECU. You may implement | achieve by DSP (Digital Signal Processor) called virtual ECU instead of ECU. The engine / dynamo control unit 30 gives a control parameter (for example, throttle opening) to the engine 12. As a result, the engine 12 rotates, and the rotation is transmitted to the dynamometer 20 via the shaft 22. The control parameters given from the engine / dynamo control unit 30 include the engine speed, throttle opening, fuel injection amount, air injection amount, fuel / air mixture ratio, ignition time (in the case of a gasoline engine), fuel There are various parameters such as the injection control method (in the case of a diesel engine).

  The engine / dynamo control unit 30 has a function of variably controlling the current / voltage applied to the dynamometer 20, and the load torque of the engine 12 connected to the dynamometer 20 by variably controlling the current / voltage. Is controlled. In the present embodiment, the engine / dynamo control unit 30 has been described, but it may be divided into an engine control unit and a dynamo control unit.

  The engine / dynamo control unit 30 is connected to the operation management unit 40. The operation management unit 40 is a means for outputting a control signal to the engine / dynamo control unit 30 based on the operation pattern and the model 50 (see FIG. 2), and mainly includes a storage unit 42, an execution unit 44, a measurement unit 46, and system control. A portion 48 is provided.

  The operation pattern and the model 50 are input in the storage unit 42 in advance. The driving pattern shows the driving plan (test plan) of the engine 12, and for example, the relationship between the speed and time of the vehicle on which the engine 12 is mounted is shown as a pattern. Specifically, in the 10.15 mode or the JC08 mode. The corresponding pattern is shown. On the other hand, the model 50 expresses a relationship (transfer characteristic) intervening between an arbitrary input and output by an expression, a graph, and the like, and a virtual version of the operation of the engine 12 is stored in the storage unit 42 in advance. The type and form of the model 50 are not particularly limited, but it is necessary to use a model that can output at least the rotational speed of the engine 12 and the accelerator opening from the information shown in the operation pattern, for example, as shown in FIG. The driver model 52, the engine model 54, and the vehicle model 56 are used in combination. In the figure, a driver model 52 is a model in which the driver's movement is hypothesized. The information from the driving pattern and the vehicle speed that is the output of the vehicle model 56 described later are input values, and the accelerator opening of the vehicle is the output value. It is said. The engine model 54 is a model in which the operation of the engine 12 is virtualized. The accelerator opening from the driver model 52 and the torque from the vehicle model 56 are input values, and the rotation speed of the engine 12 is an output value. The engine model 54 includes a virtual state of a steady state (a state in which a parameter value is stabilized at a constant value, for example, a test state in which the parameter is changed stepwise), or a transient state (a parameter is changed over time). In this case, a virtual one that is continuously changed) is appropriately selected. The vehicle model 56 is a model imagining the operation of the vehicle on which the engine 12 is mounted. The accelerator opening from the engine model 54 is an input value, and the torque applied to the engine 12 and the vehicle speed are output values. By executing a simulation by combining these models 52, 54, and 56, it is possible to obtain predicted values of the accelerator opening, the number of revolutions of the engine 12, torque, and vehicle speed. Although this embodiment will be described using an example of using a model created in advance, a model is created from data obtained by testing, or the created model is verified with data and corrected. Also good.

  The execution unit 44 is a part that executes a simulation using the model 50. The simulation is executed so as to be in the state shown in the operation pattern, and each parameter is output. Of the output values shown in FIG. 2, the rotational speed and torque of the engine 12 are output as command values to the engine / dynamo control unit 30, and the engine 12 and the dynamometer 20 are controlled according to the output values. Further, the accelerator opening and the rotational speed are output to a temperature control device 70 described later, and the cooling device 50 is controlled based on the output value.

  The measuring unit 46 shown in FIG. 1 is a means for performing various signal processing on the data indicating the measured values, and data indicating the operating state of the engine 12 is input from the engine / dynamo control unit 30 or the torque meter 26 or the like. Then, signal processing such as noise removal and various calculations is performed on these data.

The system control unit 48 is a means for performing various controls and has a function of setting (defining) various conditions of measurement contents, such as accelerator opening, fuel injection timing, ignition advance, injection time, VVT, EGR, etc. control parameters and the inlet air temperature, exhaust temperature, fuel injection amount, the air injection amount, NO _X density, HC density, CO concentration, CO ₂ concentration, the fuel consumption, the measurement parameters such as temperature, the presence or entrance of the input and output The output range can be set. In addition, setting conditions that are frequently used are registered in advance as standard actions. For example, settings for changing the input conditions in a rectangular wave shape or gradually changing the input conditions in steps are registered in advance. The operator can easily set the measurement conditions by selecting from these standard actions. The system control unit 48 has a function of freely creating a sequence in addition to a standard action set in advance. The sequence creation means is not particularly limited. For example, it is created by using a MATLAB-registered m-file or Simulink (registered trademark). By creating a sequence in this way, the operator can freely set the simulation conditions. It should be noted that the input setting at the time of definition is preferably set based on the experimental design method (DOE) or the central composite design (CCF). At that time, it is preferable to set so that the response surface can be sufficiently obtained by the output value. Further, an operation at the time of definition is performed using an operation unit 59 including a keyboard and a plurality of operation buttons, and the defined conditions are stored in the storage unit 42.

  Furthermore, the system control unit 48 has a function of executing measurement, and is configured to execute measurement based on a defined condition (or sequence). The system control unit 48 may include an automatic search function that automatically searches for a boundary value of a boundary error (for example, knocking or misfire). Further, an analysis device may be connected to the system control unit 48, an optimum point of the parameter measurement value may be formulated by the analysis device, and an ECU map may be created. At this time, the optimal point is not particularly limited, and for example, the optimal point may be determined by creating a response surface using the least square method.

  A display unit 58 is connected to the operation management unit 40 described above. The display unit 58 displays various data stored in a memory (not shown), various virtual models, various calculation results, and various simulation results. The display unit 58 displays various images such as a relationship graph, a trajectory, a frequency distribution table, and a standard deviation graph of a plurality of data. By displaying the simulation result in a graph on the display unit 58, the robustness can be checked. The display unit 58 may simultaneously display a plurality of items such as data, maps, and graphs on the same screen.

  By the way, the engine 12 described above is covered with a jacket (not shown), and the engine 12 is configured to be cooled by flowing cooling water through the jacket. Further, a pump (not shown) is provided inside the engine 12, and the cooling water in the jacket can be circulated by driving the pump. In general, the discharge amount of the pump varies according to the rotation speed of the engine 12, and the discharge amount increases as the rotation speed of the engine 12 increases.

  A cooling device 60 is connected to the engine 12, and cooling water (secondary refrigerant) is supplied from the cooling device 60 to the engine 12. The configuration of the cooling device 60 is not particularly limited. For example, the cooling device 60 includes a heat exchanger 62 that cools the cooling water with industrial water (primary refrigerant). An industrial water pipe 66 is connected to the heat exchanger 62, and industrial water is supplied to the heat exchanger 62 through the industrial water pipe 66. A cooling water pipe 64 is connected to the heat exchanger 62, and cooling water from the engine 12 is supplied through the cooling water pipe 64. In the heat exchanger 62, the industrial water and the cooling water exchange heat, whereby the cooling water is cooled and circulated and supplied to the engine 12.

  A sensor 65 is disposed in the vicinity of the outlet of the engine 12 in the cooling water pipe 64, and the temperature of the cooling water immediately after flowing out of the engine 12 is measured as the temperature of the engine 12 by the sensor 65. The sensor 65 is connected to a temperature control device 70 to be described later, and a measurement value signal is output to the temperature control device 70.

  Further, a bypass pipe 67 is connected to the cooling water pipe 64 before the heat exchanger 62 so that a part of the cooling water flows to the bypass pipe 67 without flowing to the heat exchanger 62. At the connection position, a three-way valve 68 is arranged. By adjusting the flow rate with this valve 68, the flow rate of the cooling water flowing to the heat exchanger 62 is adjusted, and the temperature of the cooling water is adjusted. The The valve 68 is connected to a valve controller 69, and the opening degree of the valve 68 is adjusted by the valve controller 69.

  According to the cooling device 60 configured as described above, the cooling water is cooled by the industrial water in the heat exchanger 62. And the engine 12 is cooled by supplying the cooled cooling water to the jacket in the engine 12.

  The valve controller 69 is connected to the temperature control device 70. The temperature control device 70 is a device that obtains an operation amount (that is, a command value of the opening degree) of the valve 68, and outputs a control signal to the valve controller 69 in response thereto. As shown in the block diagram of FIG. Unit 74 and FF control unit 72.

  The target temperature from the operation management unit 40 and the FB temperature (cooling water temperature) from the sensor 65 are input to the PI control unit 74, and the valve 68 is set so that the difference between the two decreases. Is controlled in feedback.

  On the other hand, the rotational speed and torque (throttle opening) of the engine 12 from the operation management unit 40 are input to the FF control unit 72. The FF control unit 72 stores an operation amount map 76, a dead time map 77, and a delay time map 78.

  The operation amount map 76 stores an appropriate operation amount (opening degree of the valve 68) of the heat exchanger 62 in relation to torque for each number of revolutions of the engine 12. For example, the map shown in FIG. 6 is stored. The By inputting the rotation speed and torque (throttle opening) of the engine 12 to the operation amount map 78, an appropriate operation amount of the heat exchanger 62 is output.

  The dead time map 77 indicates the time (hereinafter referred to as dead time) from when the state of the engine 12 (rotation speed, torque) is changed until the temperature of the engine 12 (measured value of the sensor 65) starts to change. For example, a map shown in FIG. 7 is stored. When the rotation speed and torque of the engine 12 are input to the dead time map 77, the dead time Δt is output. The timing of heat generation of the engine 12 and the timing of cooling by the heat exchanger 62 can be matched by shifting the output signal from the aforementioned operation amount map 76 by the dead time Δt.

  The delay time map 78 shows a variable related to the temperature gradient when the engine 12 generates heat in relation to the torque for each number of revolutions of the engine 12. For example, the map shown in FIG. 8 is stored. When the engine speed and torque of the engine 12 are input to the delay time map 78, a delay time variable τ is output and multiplied by 1 / (1 + τs). Thereby, the inclination of the operation amount is corrected, and the cooling amount is controlled according to the inclination of the heat generation amount.

  According to the FF control unit 74 configured as described above, an appropriate operation amount is output from the operation amount map 76 only by inputting the rotational speed and torque of the engine 12, and a dead time map 77 and a delay time map 78 are further output. Output dead time and delay time. Therefore, the operation amount, timing, and inclination of the heat generation of the engine 12 and the cooling by the heat exchanger 62 can be matched. That is, the heat exchanger 62 can be cooled in accordance with the heat generated by the engine 12, and the time until the temperature becomes stable can be shortened.

  Next, an operation method of the engine test apparatus 10 of the present embodiment will be described. FIG. 4 shows an operation flow of the engine test apparatus 10.

  As shown in the figure, first, the engine 12 is set on the gantry 14. (Step S1)

  Next, in order to obtain data for creating a map, a pre-test is performed (step S2). In the pre-test, by inputting the rotation speed and torque of the engine 12 and performing feedback control, data of a temperature change curve until the temperature of the engine 12 becomes stable (see FIG. 5) and heat when the temperature is stabilized. Stores the operating amount of the exchanger. Then, the same test is repeated while changing the operating condition by changing one (or both) of the rotational speed and the torque. At that time, the rotation speed and the torque are changed at predetermined intervals, and are changed so as to form a lattice when a graph with two parameters is created. By performing a number of steady tests in this manner, manipulated variable data and temperature change curve data are obtained for each engine speed and torque.

  Next, parameters of the engine model 54 are determined from data such as the rotation speed, torque, and temperature obtained in the pre-test, and the engine model 54 is created (step S3).

  Next, various maps 76, 77, and 78 are created from the manipulated variable and temperature change curve data obtained in the pre-test (step S4). For example, the operation amount map 76 is created by inputting an operation amount for each rotation speed and torque of the engine 12.

  To create the dead time map 77, first, the dead time Δt is obtained from the temperature change curve. Specifically, in the temperature change curve shown in FIG. 5, when the state of the engine 12 changes at time a and the temperature of the engine 12 starts to rise at time b, Δt from time a to time b is used as a dead time. And A dead time map 77 is created by inputting this for each rotation speed and torque of the engine 12.

  In order to create the delay time map 78, first, a delay time variable τ is obtained for each rotation speed and torque of the engine 12 from the temperature change curve. Specifically, first, a simulation is performed based on the engine model 54 stored in the storage unit 42 of the operation management unit 40, and the rotational speed and accelerator opening (torque) of the engine 12 are obtained. Then, the amount of heat generation is obtained from the rotational speed and torque of the engine 12, and the simulation result of the temperature change curve of the engine 12 is obtained. The value of the variable τ is searched and determined so that the temperature change curve of the simulation result thus obtained matches the temperature change curve of the pre-test (FIG. 5). A delay time map 78 is created by inputting the determined variable τ for each rotation speed and torque of the engine 12.

  After creating the various maps 76, 77, 78, a normal main test is performed (step S5). At that time, the target temperature of the engine 12 and the engine speed and torque data are input from the operation management unit 40 to the temperature controller 70, and the coolant temperature at the outlet of the engine 12 is input from the temperature sensor 65 to the temperature controller 70. Is entered. The temperature control device 70 performs FF control based on the various maps 76, 77, and 78 and performs FB control based on the deviation between the target temperature and the outlet temperature so that the temperature of the engine 12 becomes the target temperature. To do. Thereby, various tests of the engine 12 can be performed in a state where the temperature of the engine 12 is controlled.

  FIG. 9 shows the effect of the present invention. FIG. 9A shows the change over time in the opening command value, and FIG. 9B shows the change over time in the temperature sensor. In these drawings, the solid line indicates the case of the present embodiment, and the dotted line indicates the case of the comparative example. In the comparative example, only the operation amount map 76 is used, and the FF control is performed without using the dead time map 77 and the time delay map 78.

  As can be seen from these figures, in the case of the comparative example, the valve opening command value fluctuates more than necessary, and the temperature fluctuates also. This seems to be because the timing and inclination of heat generation and cooling do not match because there is no dead time map 77 and time delay map 78.

  On the other hand, in the present embodiment, the valve opening command value does not fluctuate more than necessary, and the fluctuation in temperature is much smaller than in the comparative example.

  As described above, according to the present embodiment, since the FF control is performed using not only the operation amount map 76 but also the dead time map 77 and the delay time map 78, the responsiveness and accuracy of the temperature control of the engine 12 are improved. be able to. That is, when the FF control is performed only by the operation amount map 76, the timing of heat generation and cooling is shifted by the waste time Δt, or the slope of heat generation and cooling is shifted by the delay time. In the present embodiment, since these deviations are corrected in advance and the heat exchanger 62 is controlled, the temperature of the engine 12 can be quickly and accurately controlled to the target temperature.

  In addition, according to the present embodiment, a pre-test is performed using the engine 12 for the main test, and various maps 76, 77, and 78 are created. There is no error every time the type is changed. Therefore, temperature control can be accurately performed in all the engines 12.

  In the above-described embodiment, both the dead time map 77 and the delay time map 78 are used. However, the present invention is not limited to this, and when the influence of one of the devices is small, the dead time map 77 is used. Or only the delay time map 78 may be used.

DESCRIPTION OF SYMBOLS 10 ... Engine bench, 12 ... Engine, 20 ... Dynamometer, 30 ... Engine dynamo control part, 40 ... Operation management part, 42 ... Memory | storage part, 44 ... Execution part, 50 ... Model, 52 ... Driver model, 54 ... Engine Model, 56 ... Vehicle model, 60 ... Cooling device, 62 ... Heat exchanger, 68 ... Valve, 69 ... Valve controller, 70 ... Temperature controller, 72 ... FF controller, 74 ... PID controller, 76 ... Heat value map , 77 ... Waste time map, 78 ... Delay time map

Claims (4)

An engine test apparatus comprising: a heat exchanger that adjusts a temperature of cooling water that circulates between the engine; and a temperature control device that controls the temperature of the engine to a temperature target value by operating the heat exchanger. In
The temperature control device includes an operation amount map showing an operation amount of the heat exchanger with respect to a state of the engine,
A dead time map showing the dead time until the temperature of the engine starts to change after changing the state of the engine;
A time delay map in which time delay variables for engine temperature changes are shown for the engine condition;
An engine test apparatus that controls the temperature of the engine based on the manipulated variable map, the dead time map, and the time delay map.   The temperature control device performs a pre-test by feedback control under a plurality of conditions by changing the state of the engine, and creates the manipulated variable map, the dead time map, and the time delay map. The engine test apparatus according to claim 1. In the engine test method for testing the engine in a state where the temperature of the engine is controlled by a heat exchanger
Performing a test by feedback control under a plurality of conditions by changing the state of the engine, and a pre-testing step for obtaining data on the operation amount of the heat exchanger and the temperature of the engine;
Based on the obtained data, the operation amount map in which the operation amount of the heat exchanger is shown with respect to the state of the engine, and until the temperature of the engine starts to change after the state of the engine changes. A map creation step of creating a dead time map in which the dead time is indicated with respect to the engine state, and a time delay map in which a time delay variable related to the temperature change of the engine is indicated with respect to the engine state. When,
The engine state is input to the manipulated variable map, the dead time map, and the time delay map, and the heat exchanger is operated based on the determined manipulated variable, the dead time, and the time delay variable. A main test process for testing the engine;
An engine test method comprising: The map creating step simulates the engine temperature using a model simulating the engine test device, and compares the simulation result with the temperature change data of the engine obtained in the pre-test step. 4. The engine test method according to claim 3, wherein the time delay variable is determined.

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