Method for controlling start-up of power generation system and device for controlling start-up of power generation system

Abstract

In this method for controlling the starting of a power generation system, at the starting of a power generation system including an internal combustion engine which is a motive power source, a power generator, and a motive power transmission mechanism for transmitting motive power between the internal combustion engine and the power generator, the power generator is driven by electric power supplied from a battery, and rotation speed control is executed to make the rotation speed of the power generator match a target rotation speed. In this method for controlling the starting of a power generation system, electric power that can be output by the battery is acquired and the rotation speed of the power generator is acquired. In addition, a filtering process is performed on the rotation speed of the power generator to reduce a resonance frequency band component of a spring-mass system constituted of the internal combustion engine, the power generator, and the motive power transmission mechanism. Furthermore, an upper limit torque, which is an upper limit for the torque of the power generator, is calculated on the basis of the filtered rotation speed and the electric power that can be output. The rotation speed control is then executed under the limitation provided by this upper limit torque.

Description

[Technical Field]

[0001] The present invention relates to a start-up control method and a start-up control device for a power generation system. [Background technology]

[0002] JP2021-124058A discloses an engine start control device that, when starting an engine (internal combustion engine) mounted on a vehicle as a driving force source, rotates the engine using a motor whose rotation speed can be controlled. Summary of the Invention

[0003] Some modern vehicles are equipped with a power generation system that includes an engine as a power source, a generator, and a power transmission mechanism that transmits power between the engine and the generator. When starting a power generation system equipped in a vehicle, the generator is driven by power supplied from a battery, causing the engine to idle (so-called motoring). For example, in so-called series hybrid vehicles, control is typically performed in which the engine speed is increased to a predetermined rotational speed by motoring, and then the engine is ignited to start power generation. When the rotational speed of the generator or the like is within the resonant frequency band of the power generation system, the power generation system oscillates. To reduce such oscillation, a starting method is employed in which the rotational speed is quickly increased to a rotational speed higher than the resonant frequency band by motoring, as described above.

[0004] However, when starting a power generation system, if the battery's output power is insufficient to drive the generator, motoring cannot quickly increase the engine speed to the speed required to start power generation. In this case, the rotation speed of the generator, etc., remains in the resonant frequency band for a long time, which is a problem in that oscillations of the power generation system are not reduced. Furthermore, if motoring at startup is performed by rotation speed control that matches the generator rotation speed to a target rotation speed, this exacerbates the rotation speed fluctuations of the generator, etc., and the time that the generator remains in the resonant frequency band is likely to be particularly long.

[0005] The present invention aims to provide a startup control method for a power generation system, and a startup control device for a power generation system, which can quickly increase the rotation speed of a generator or the like to a rotation speed exceeding the resonant frequency band by motoring, even if the power that the battery can output when starting the power generation system is small.

[0006] One aspect of the present invention is a startup control method for a power generation system including an internal combustion engine as a power source, a generator, and a power transmission mechanism that transmits power between the internal combustion engine and the generator. When starting the power generation system, the method drives the generator with power supplied from a battery and performs rotation speed control to match the rotation speed of the generator to a target rotation speed. In this power generation system startup method, the battery's available output power is obtained, and the generator rotation speed is obtained. A filtering process is then performed on the generator rotation speed to reduce components in the resonant frequency band of a spring mass system formed by the internal combustion engine, the generator, and the power transmission mechanism. Furthermore, an upper limit torque, which is an upper limit for the torque of the generator, is calculated based on the filtered generator rotation speed and the battery's available output power. Then, rotation speed control is performed under the restriction imposed by this upper limit torque. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a block diagram showing the configuration of a vehicle equipped with a power generation system. [Figure 2] FIG. 2 is an explanatory diagram showing the start mode of the power generation system according to the engine temperature and the battery's available output power. [Figure 3] FIG. 3 is an explanatory diagram showing the change in the generator rotation speed and the engine ignition timing in the first cryogenic temperature start mode. [Figure 4] FIG. 4 is an explanatory diagram showing the relationship between the SOC, temperature, and available output power of the battery. [Figure 5] FIG. 5 is a graph showing the relationship between engine oil temperature and absolute viscosity of engine oil. [Figure 6]FIG. 6 is an explanatory diagram showing changes in the generator rotation speed, the engine ignition timing, and the generator torque in the second cryogenic temperature start mode. [Figure 7] FIG. 7 is an explanatory diagram showing engine torque and generator torque when the rotation speed control is performed in the second cryogenic temperature start mode. [Figure 8] FIG. 8 is a flowchart relating to the selection of the starting mode. [Figure 9] FIG. 9 is a flowchart of the rotation speed control in the second cryogenic temperature start mode. [Figure 10] FIG. 10 is a graph of a comparative example showing torque and rotation speed when start control in the second cryogenic temperature start mode is performed using an upper limit torque that has not been filtered in a cryogenic temperature environment. [Figure 11] FIG. 11 is an example graph showing torque and rotation speed when starting a power generation system in a cryogenic environment using the second cryogenic start mode. [Figure 12] FIG. 12 is a graph showing the available output power of the battery and the actual power consumption by the generator. [Figure 13] FIG. 13 is an explanatory diagram showing the effect of a margin set for the available output power of a battery. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0009] FIG. 1 is a block diagram showing the configuration of a vehicle 100 equipped with a power generation system 10. As shown in FIG. 1, the vehicle 100 of this embodiment is a series-type hybrid vehicle equipped with the power generation system 10, a battery 11, a motor 12, and a vehicle controller 13 that controls these components in an integrated manner. That is, the vehicle 100 charges the battery 11 with electric power generated by the power generation system 10. The vehicle 100 then travels by driving the drive motor 12 with electric power from the battery 11. However, the present invention can also be suitably implemented in other types of hybrid vehicles as long as the vehicle is equipped with the power generation system 10. The present invention can also be applied to power generation systems other than the power generation system 10 installed in the vehicle 100.

[0010] The power generation system 10 includes an engine 14 , a generator 15 , and a power transmission mechanism 16 .

[0011] The engine 14 is a so-called internal combustion engine, and is the power source of the power generation system 10. The rotation speed of the engine 14 (hereinafter referred to as engine rotation speed N E ), torque (hereinafter referred to as engine torque T E Various parameters representing the operating state of the engine 14, such as the temperature of the engine 14, can be detected or acquired as appropriate by sensors (not shown) or calculations. In this embodiment, the temperature of the engine 14 is determined as the temperature of the engine oil (hereinafter referred to as the engine oil temperature T oil ) is obtained.

[0012] When the power generation system 10 generates power, the engine 14 generates an engine torque T E is the target value according to the amount of power generation and power generation efficiency (hereinafter referred to as the engine torque target value T E * The control for making the torque coincide with the target torque is called torque control. The torque control of the engine 14 is performed, for example, by controlling the actual engine torque T E and engine torque target value T E *This is achieved by feedback control such as PI control (Proportional-Integral Control) based on the above.

[0013] Depending on the actual configuration of the vehicle 100, the engine 14 may input power to the drive motor 12 instead of inputting power to the generator 15, and may become a power source that drives the vehicle 100. For simplicity, in this embodiment, the engine 14 is driven only when necessary to generate power, and the power is input to the generator 15.

[0014] The generator 15 generates electricity using the power output by the engine 14, and charges the battery 11 with the electricity. When the power generation system 10 is started, the generator 15 is driven using the power of the battery 11, causing the engine 14 to idle (hereinafter referred to as motoring). The rotational speed of the generator 15 (hereinafter referred to as generator rotational speed N G ) and torque (hereafter referred to as generator torque T G Various parameters indicating the operating state of the generator 15, such as the above, can be detected or obtained as appropriate by sensors, calculations, etc. (not shown).

[0015] At least when the power generation system 10 generates power, the generator 15 rotates at a generator rotation speed N G is the target value according to the power generation amount and power generation efficiency (hereinafter simply referred to as the target rotation speed N G * Therefore, when generating power, the generator rotation speed N G The engine speed N E is determined. The control for matching the rotation speed with the target rotation speed as described above is called rotation speed control. In this embodiment, the generator 15 is controlled by the rotation speed control, especially when the power generation system 10 is started. The rotation speed control of the generator 15 is performed, for example, by adjusting the actual generator rotation speed N G and target rotation speed N G * This is achieved by feedback control such as PI control based on the

[0016] The power transmission mechanism 16 is a mechanical mechanism that connects the engine 14 and the generator 15, and transmits power between the engine 14 and the generator 15. The power transmission mechanism 16 is configured, for example, by a damper, a reducer, a transmission, or a combination of these. In any case, the power transmission mechanism 16 functions as a spring element, a damping element, or a spring element and a damping element with respect to the transmission of power. Therefore, the engine 14, the generator 15, and the power transmission mechanism 16 (i.e., the power generation system 10) constitute a so-called spring-mass system, and a specific resonant frequency ω depends on the specific configuration of the system. p (not shown). Therefore, the engine speed N E and generator rotation speed N G However, this resonant frequency ω p or the frequency band nearby (hereinafter referred to as the resonant frequency band B RF When the engine 14, the generator 15, and the power transmission mechanism 16 are stagnant, large vibrations may occur in the power generation system 10. In the following, the resonance frequency ω p and resonance frequency band B RF and the resonant frequency ω of the power generation system 10. p , and the resonant frequency band B of the power generation system 10 RF That's what they say.

[0017] The battery 11 is a secondary battery and is rechargeable. The battery 11 is typically a lithium-ion battery. The battery 11 supplies power to drive the motor 12. When the power generation system 10 is started, the battery 11 also supplies power to drive the generator 15. In principle, the battery 11 is charged with power generated by the power generation system 10. However, the battery 11 can also be charged with power generated by the motor 12 through so-called regenerative control. The battery 11 also supplies power to the accessories 17. The accessories 17 are devices that require power, such as lights, speakers, a car navigation system, and an air conditioner of the vehicle 100.

[0018] SOC (State of Charge), temperature, and available output power P of battery 11out , and the available input power P in The various parameters representing the state of the battery 11, such as the above, can be detected or obtained as appropriate by sensors (not shown) or calculations, etc. The SOC is a parameter that serves as an index of the state of charge (charge amount) of the battery 11.

[0019] The motor 12 is a driving electric motor, and generates a driving force for the vehicle 100 by the torque it outputs. The motor 12 is connected to the driving wheels 20 via a gear 18 and a driving shaft 19. Therefore, the torque output by the motor 12 generates a driving force for the driving wheels 20. The rotation speed of the motor 12 (hereinafter referred to as the motor rotation speed N M ) and torque (hereinafter referred to as motor torque T M Various parameters indicating the operating state of the motor 12, such as the rotation speed (rpm) and rotation speed (rpm), can be detected or obtained as appropriate by sensors, calculations, etc. (not shown).

[0020] The vehicle controller 13 is a control device that performs overall control of each part of the vehicle 100 using an engine controller 21, a generator controller 22, a motor controller 23, a battery controller 24, etc. These controllers are configured with one or more computers and are programmed to control each part of the vehicle 100 at a predetermined control cycle. These controllers may also include circuits, sensors, etc. for controlling each part of the vehicle 100 as necessary. In this embodiment, for example, the generator controller 22 includes an inverter that controls the power input and output to the generator 15.

[0021] Furthermore, all or some of these controllers constitute a control device that controls devices or systems of specific parts of the vehicle 100. For example, the vehicle controller 13, the engine controller 21, and the generator controller 22 constitute a control device for the power generation system 10. In particular, the vehicle controller 13, the engine controller 21, and the generator controller 22 constitute a start control device that performs start control of the power generation system 10. Furthermore, the vehicle controller 13 and the motor controller 23 constitute a drive control device that controls the drive of the vehicle 100.

[0022] The vehicle controller 13 acquires parameters that indicate the operating state of each part of the vehicle 100, and controls each part of the vehicle 100 using these parameters.

[0023] Specifically, the vehicle controller 13 detects the engine oil temperature T oil , engine speed N E , generator rotation speed N G , engine torque T E , generator torque T G , the SOC of the battery 11, the output power P of the battery 11 out , and the inputtable power P of the battery 11 in The vehicle controller 13 then controls the start-up and power generation of the power generation system 10 based on these parameters.

[0024] When generating power in the power generation system 10, the vehicle controller 13 calculates the amount of power generation required of the power generation system 10 (hereinafter referred to as the required power generation amount) based on the SOC of the battery 11, etc. Then, the vehicle controller 13 determines the engine torque target value T E * and target rotation speed N G * Calculate the engine torque target value T E * is input to the engine controller 21, and the target rotation speed N G * is input to the generator controller 22. As a result, the engine controller 21 inputs the engine torque T E is the engine torque target value T E * The torque of the engine 14 is controlled so that it coincides with the generator rotation speed N G is the target rotation speed N G * The rotation speed of the generator 15 is controlled so that it coincides with the required power generation amount. As a result, the power generation system 10 generates power according to the required power generation amount and charges the battery 11.

[0025] When starting power generation when the power generation system 10 is in a stopped state, the vehicle controller 13 executes start-up control to start the power generation system 10 prior to the above-described power generation control. In the start-up control, the vehicle controller 13 executes a start-up control to start the power generation system 10. G * The resonance frequency band B RF The generator controller 22 then sets the generator rotation speed N G is a predetermined value set in advance. G * The engine speed is controlled to match the engine speed, thereby motoring the engine 14. Thereafter, the vehicle controller 13 ignites the engine 14 by giving permission to ignite the engine 14 to the engine controller 21, and the control sequence of the power generation system 10 is shifted from start-up control to power generation control.

[0026] When the start control is executed, the vehicle controller 13 controls the generator rotation speed N G and the output power P of the battery 11 out Based on this, an upper limit value for the torque of the generator 15 (hereinafter referred to as upper limit torque ULT G Then, the vehicle controller 13 sets the upper limit torque ULT G The torque target value (hereinafter referred to as the generator torque target value T G * Therefore, the rotation speed control of the generator 15 in the start control is performed by setting the generator torque T G is the upper limit torque ULT G Do not exceed the upper limit torque ULT G In this embodiment, the vehicle controller 13 is particularly configured to detect the resonant frequency band B RF (resonant frequency ω p ) filtered according to the upper limit torque ULT G-flt The start-up control of the power generation system 10, particularly the resonant frequency band B RFUpper limit torque ULT filtered to reduce the G-flt The start control performed under the above restrictions will be described in detail later.

[0027] The vehicle controller 13 also determines the accelerator opening A po and motor rotation speed N M Specifically, the vehicle controller 13 controls the driving of the vehicle 100 based on the accelerator opening A po and motor rotation speed N M Based on the above, the motor torque target value T M * and inputs the result to the motor controller 23. The motor controller 23 determines whether the output torque of the motor 12 reaches the motor torque target value T M * Torque control is performed so that the throttle opening A po The vehicle 100 is driven by the driving force required by the accelerator opening A po is a parameter that indicates the amount of operation of an accelerator pedal (not shown), and is suitably detected using a sensor (not shown) or the like.

[0028] The battery controller 24 controls the input and output of power to the battery 11 in response to requests from the vehicle controller 13, etc. The battery controller 24 also controls the SOC and available output power P out , and the available input power P in etc. are measured and input to the vehicle controller 13.

[0029] Among the various types of control described above, the start-up control of the power generation system 10 will be described in detail below.

[0030] [Start-up control of power generation systems] FIG. 2 shows the temperature of the engine 14 (engine oil temperature T oil ) and the outputtable power P of the battery 11 out 2 is an explanatory diagram showing the start-up modes of the power generation system 10 according to the above. As shown in FIG. 2, the start-up modes of the power generation system 10 include a normal start-up mode SN and cryogenic start mode S LT There is.

[0031] Normal start mode S N is the temperature of the engine 14, i.e., the engine oil temperature T oil is a predetermined temperature TH oil This is the start mode that is selected when the engine is running at a higher speed. N is the generator rotation speed N G (and engine speed N E ) is the resonant frequency band B of the power generation system 10 RF A predetermined rotation speed TH that is higher than the rotation speed TH and is unlikely to generate noise or vibration in parts other than the power generation system 10. NGn This is a start mode in which the engine 14 is ignited after motoring until the engine speed reaches 1000 rpm. The frequency band (rotation speed band) in which noise and vibration occur in parts other than the power generation system 10 is usually within the resonant frequency band B RF It is in a higher frequency range than

[0032] Cryogenic start mode S LT is the engine oil temperature T oil is the predetermined temperature TH oil This is the start mode that is selected when the engine oil temperature is below T oil is the predetermined temperature TH oil The temperature at which the temperature is below 100°C.

[0033] Also, cryogenic start mode S LT The first cryogenic start mode S LT1 and the second cryogenic start mode S LT2 First cryogenic start mode S LT1 and the second cryogenic start mode S LT2 is the outputtable power of the battery 11 required to drive the generator 15 during start-up control (hereinafter referred to as required power NP out ) and the actual output power P of the battery 11 out Either one is selected depending on the relationship between

[0034] First cryogenic start mode S LT1 is the output power P of the battery 11.out The required power is NP out First cryogenic start mode S is selected when LT1 is the generator rotation speed N G (and engine speed N E ) is the resonant frequency band B of the power generation system 10 RF A predetermined rotation speed TH higher than NG1 This is a start mode in which the engine 14 is ignited after motoring up to the temperature. LT1 At a given rotation speed TH NG1 is set within a range that would cause noise and vibration in parts other than the power generation system 10. NGn >TH NG1 and normal start mode S N Compared to the first cryogenic start mode S LT1 is a start-up mode in which the power generation system 10 is started up while ignoring the sound and vibration reduction request for parts other than the power generation system 10 .

[0035] Second cryogenic start mode S LT2 is the output power P of the battery 11. out The required power is NP out The second cryogenic start mode S is selected when LT2 When the power of the battery 11 is insufficient, the generator rotation speed N G (and engine speed N E ) in the resonant frequency band B of the power generation system 10 RF Selected when motoring to a higher speed than 0 is not possible. Alternatively, the second cryogenic start mode S LT2 is the resonant frequency band B RF Target RPM N higher than G * This is selected when motoring up to the maximum temperature would take a long time. LT2 So, resonant frequency band B RF Lower than the specified rotation speed TH NG2 The engine 14 is then ignited. Thus, the second cryogenic start mode S LT2is at a cryogenic temperature and in the resonant frequency band B RF Lower than the specified rotation speed TH NG2 This is the "low rotation start mode" that motors up to 1000rpm.

[0036] Figure 3 shows the first cryogenic start mode S LT1 generator rotation speed N G Changes in the ignition timing of engine 14 F FIG. 10 is an explanatory diagram showing the first cryogenic start mode S LT1 In scenarios where this is selected, even in extremely low temperature environments, the battery 11 requires only NP out Therefore, as shown in FIG. 3, from the start of the power generation system 10, the resonant frequency band B RF A predetermined rotation speed TH NG1 Resonant frequency band B RF Motoring is performed to pass through as quickly as possible, and then the engine 14 is ignited.

[0037] However, in an extremely low temperature environment, the output power P of the battery 11 is usually out The engine oil temperature T oil As the viscosity of the battery 11 increases, the required power NP out may not be able to meet the above requirements.

[0038] FIG. 4 shows the SOC and temperature T LB , and the available output power P out 4 is an explanatory diagram showing the relationship between the available output power P out Therefore, in an extremely low temperature environment, the performance of the battery 11 is particularly deteriorated, and the required power NP out The output power P out may decrease.

[0039] Figure 5 shows the engine oil temperature T oil and the absolute viscosity of engine oil V absAs shown in FIG. 5, the relationship between the engine oil temperature T oil When the absolute viscosity of the engine oil decreases, V abs increases exponentially. Therefore, in an extremely low temperature environment, the friction resistance of the engine 14 may increase extremely. In an extremely low temperature environment, the engine 14 must be motored against such friction resistance, so the engine oil temperature T oil As the required power NP decreases, out The required power NP of the battery 11 increases exponentially (see Figure 2). out When it is not possible to supply the second cryogenic start mode S LT2 A low-speed start using the

[0040] Figure 6 shows the second cryogenic start mode S LT2 generator rotation speed N G Change in engine 14 ignition timing t F , and generator torque T G FIG. 6(A) is an explanatory diagram showing the change in the second cryogenic start mode S LT2 generator rotation speed N G Changes in the ignition timing of engine 14 F Also, FIG. 6(B) shows the second cryogenic start mode S LT2 The generator torque T G Shows the change in

[0041] As shown in Figures 6(A) and 6(B), the second cryogenic start mode S LT2 There are three control stages: a first stage Ph1, a second stage Ph2, and a third stage Ph3.

[0042] The first stage Ph1 is the resonant frequency band B RF Lower than the specified rotation speed TH NG2 In this first stage Ph1, the engine 14 is motored until the predetermined rotation speed TH NG2 At such a low rotation speed, engine torque T EThe starting (driving) of the engine 14 is assisted by motoring so that the engine 14 can output the torque.

[0043] The second stage Ph2 is the motoring by the generator 15 and the engine torque T generated by the combustion of the engine 14. E (Compression reaction force) and the resonance frequency band B RF In this embodiment, the second phase Ph2 is a control phase exceeding the first cryogenic start mode S LT1 The rotation speed TH to be reached when NG1 Up to generator rotation speed N G and engine speed N E Increases.

[0044] The third phase, Phase 3, is the second cryogenic start mode S. LT2 This is the control stage where the start control is shifted from the start control by the inverter to the normal power generation control.

[0045] The dashed line in Figure 6(B) represents the generator torque T G Upper limit torque ULT G The overall change in the upper limit torque ULT is shown in the figure. G is the output power P of the battery 11. out , generator rotation speed N G , and a predetermined conversion coefficient C, is used to calculate the upper limit torque ULT G is the output power P of the battery 11. out The maximum generator torque T that the generator 15 can output is G Represents.

[0046]

number

[0047] Required power NP out The output power P of the battery 11 out If is large enough, the upper limit torque ULT G is controlled by the generator speed N GTherefore, the first cryogenic start mode S LT1 In such cases, the upper limit torque ULT G The generator torque T G However, the second cryogenic start mode S LT2 As in the scene where out If is small, the upper limit torque ULT G The upper limit torque ULT G is controlled by the generator speed N G is close to the range in which the generator torque T G is the upper limit torque ULT G may be limited by

[0048] In particular, the second stage Ph2 is G and engine speed N E Since this is a control step to increase the generator rotation speed N G Therefore, as shown in FIG. 6(B), the generator torque T G and upper limit torque ULT G are particularly close to each other, and the generator torque T G is the upper limit torque ULT G The upper limit torque ULT G Generator torque T G is a response delay in the rotation speed control. Therefore, by controlling the rotation speed, the generator rotation speed N G As a result, the generator speed N G and engine speed N E is the resonant frequency band B RF and quickly shifts to resonance frequency band B. RF Therefore, the second stage Ph2 is longer. G is the upper limit torque ULT G If the power generation system 10 is limited by this, vibrations are likely to occur.

[0049] Figure 7 shows the second cryogenic start mode S LT2 When controlling the engine speed, the engine torque T E and generator torque T G FIG. 7(A) is an explanatory diagram showing the second cryogenic start mode S LT2 The ideal engine torque T when controlling the rotation speed is E and generator torque T G As shown in Fig. 7(A), the engine torque T E and generator torque T G has a predetermined phase difference determined by the characteristics of the power transmission mechanism 16, etc. FIG. 7(B) shows the second cryogenic start mode S LT2 Actual engine torque T when controlling the rotation speed E and generator torque T G As shown in Fig. 7(B), the actual generator torque T G The upper limit torque ULT G is the generator rotation speed N that oscillates due to rotation speed control G Since it is calculated using the generator rotation speed N G Therefore, the second cryogenic start mode S LT2 At the upper limit torque ULT G and generator torque T G When these two approach each other, the generator torque T G is the upper limit torque ULT G and upper limit torque ULT G Therefore, as mentioned above, the generator rotation speed N G The fluctuation of the resonant frequency band B is promoted and RF , and vibrations occur in the power generation system 10.

[0050] Therefore, in this embodiment, the second cryogenic start mode S LT2 (Especially in the second stage Ph2), the upper limit torque ULT G Instead of the resonant frequency band B RF Upper limit torque ULT filtered to reduce the G-flt(Hereafter, simply referred to as upper limit torque ULT G-flt This upper limit torque ULT G-flt The rotational speed of the generator 15 is controlled under the limit of the filtered upper limit torque ULT G-flt is calculated according to the following formula (2).

[0051]

number

[0052] As shown in equation (2), the upper limit torque ULT G-flt is the upper limit torque ULT calculated by equation (1) G Instead of filtering the generator rotation speed N G That is, the vehicle controller 13 calculates the generator rotation speed N G Resonant frequency band B RF By applying filtering to reduce the component of G-flt (Hereafter, simply the generator rotation speed N G-flt Then, the vehicle controller 13 calculates the generator rotation speed N G-flt and the outputtable power P of the battery 11. out Based on the upper limit torque ULT G-flt Calculate the following.

[0053] [Effect] The operation of the start-up control of the power generation system 10 in the vehicle 100 configured as described above will be described below.

[0054] 8 is a flowchart showing the selection of the starting mode. As shown in FIG. 8, in step S11, the vehicle controller 13 determines whether the engine oil temperature T oil , and the outputtable power P of the battery 11 out In step S12, the vehicle controller 13 acquires the engine oil temperature T oil is the predetermined temperature TH oilDetermine whether the engine oil temperature T oil is the predetermined temperature TH oil If so, the process proceeds to step S13, and the vehicle controller 13 enters the normal start mode S N The power generation system 10 is started.

[0055] On the other hand, in step S12, the engine oil temperature T oil is the predetermined temperature TH oil If it is determined that the engine oil temperature T oil Based on the required power NP out The vehicle controller 13 calculates the engine oil temperature T oil and required power NP out Therefore, the vehicle controller 13 can calculate the required electric power NP from the engine oil temperature Toil by referring to this map. out Calculate the following.

[0056] In step S15, the vehicle controller 13 calculates the required power NP out The output power P of the battery 11 out Determine whether the required power NP is greater than out is the output power P of the battery 11. out The resonant frequency band B is equal to or less than the power of the battery 11. RF If it is determined that sufficient motoring exceeding the first cryogenic start mode S is possible, the process proceeds to step S16. LT1 The power generation system 10 is started.

[0057] On the other hand, in step S15, the required power NP out is the output power P of the battery 11. out The resonant frequency band B is smaller than the RFIf it is determined that sufficient motoring exceeding the second cryogenic start mode S cannot be performed, the process proceeds to step S17. LT2 The power generation system 10 is started.

[0058] Figure 9 shows the second cryogenic start mode S LT2 9 is a flowchart of the rotation speed control by the vehicle controller 13. As shown in FIG. out Based on this, the available output power P out The maximum torque that can be output from the generator 15 within the range of GM In step S22, the vehicle controller 13 calculates the available output power P of the battery 11. out and generator rotation speed N G Based on the upper limit torque ULT G-flt That is, the vehicle controller 13 calculates the obtained generator rotation speed N G Resonant frequency band B RF The generator rotation speed N G-flt is calculated and used to calculate the upper limit torque ULT according to equation (2). G-flt Then, in step S24, the vehicle controller 13 calculates the maximum powering torque T GM Upper limit torque ULT G-flt The torque limited within the range is set as the generator torque target value T G * In step S25, the vehicle controller 13 sets the target rotation speed N G * The resonance frequency band B RF First target rotation speed N lower than G1 * In this embodiment, the first target rotation speed N G1 * is the predetermined rotation speed TH NG2 In this way, the vehicle controller 13 determines the generator torque target value T G * and target rotation speed N G* By setting G is the upper limit torque ULT G-flt Within the range not exceeding the generator rotation speed N G is the first target rotation speed N G1 * The rotation speed is controlled so that it matches the

[0059] In step S26, the vehicle controller 13 controls the generator rotation speed N G is the first target rotation speed N G1 * Then, it is determined whether the generator rotation speed N G is the first target rotation speed N G1 * If it is determined that the engine torque target value T has been reached, then in step S27, the vehicle controller 13 permits fuel injection into the engine 14 and starts the engine 14. Note that in step S27, the vehicle controller 13 E * The engine torque target value for starting T E1 * (not shown). Then, in step S28, the vehicle controller 13 sets the engine torque T E By monitoring the engine torque T E Whether or not the output is stable, i.e., whether or not the output is stable. E The control up to this point is the second cryogenic start mode S LT2 Then, in step S28, the engine torque T E is stably output, the vehicle controller 13 transitions to the control of the second stage Ph2.

[0060] As shown in step S29, in the control of the second stage Ph2, the vehicle controller 13 sets the target rotation speed N G * , the generator rotation speed N G is the resonant frequency band B RF a higher rotation speed (for example, the aforementioned predetermined rotation speed THNG1 ) to the second target rotation speed N G2 * In step S30, the vehicle controller 13 sets the resonant frequency band B RF In order to quickly pass through the target engine torque T E * The engine torque target value T E2 * This sets the generator rotation speed N G and engine speed N E is the second target rotation speed N G2 * In step S31, the vehicle controller 13 increases the generator rotation speed N G or engine speed N E is the second target rotation speed N G2 * In this embodiment, the vehicle controller 13 determines whether the engine rotation speed N E Monitor the engine speed N E is the second target rotation speed N G2 * The control up to this point is the second cryogenic start mode S LT2 In step S31, the engine speed N E (or generator rotation speed N G ) is the second target rotation speed N G2 * When it is determined that the power consumption has reached the third stage, the vehicle controller 13 executes the third stage control, that is, the transition control to the power generation control.

[0061] As shown in step S32, in the control of the third stage Ph3, the vehicle controller 13 sets the target rotation speed N G * The third target rotation speed N G3 * In step S33, the vehicle controller 13 sets the engine torque target value T E *Then, in step S34, the vehicle controller 13 reduces the engine torque target value T E * Finally, the engine torque target value T E * The engine torque target value T E3 * This sets the second cryogenic start mode S LT2 The start control by the ignition is terminated and the system shifts to normal power generation control.

[0062] Figure 10 shows the upper limit torque (ULT) without filtering in a cryogenic environment. G Using the second cryogenic start mode S LT2 10A is a graph showing the torque and rotation speed when the start control is executed. G The dashed line indicates the upper limit torque ULT G In addition, Fig. 10(B) shows the generator rotation speed N G The dashed line indicates the target rotation speed N G * Shows.

[0063] As shown in Figure 10(A), the second cryogenic start mode S LT2 In the scene where is selected, the upper limit torque ULT G is the generator torque T G Therefore, as shown by the downward arrow, the generator torque T G is the upper limit torque ULT G Here, the generator torque T G Upper limit torque ULT G As shown by the upward arrow in Fig. 10(B), the generator torque T G is the upper limit torque ULT G As a result, the generator speed N G As a result, the time required for the second stage Ph2 is t A It is as follows.

[0064] Figure 11 shows the upper limit torque (ULT) after filtering in an extremely low temperature environment. G-flt Using the second cryogenic start mode S LT2 11A is a graph showing the torque and rotation speed when the start control is executed. G The dashed line indicates the upper limit torque ULT G-flt In addition, in Fig. 11(B), the solid line indicates the generator rotation speed N G The dashed line indicates the target rotation speed N G * Shows.

[0065] As shown by the downward arrow in Fig. 11(A), the filtered upper limit torque ULT G-flt Even when using the generator torque T G This upper limit torque ULT G-flt Here, the generator torque T G Upper limit torque ULT G However, as shown by the upward arrow in Figure 11(B), the upper limit torque ULT G-flt When using the generator torque T G is the upper limit torque ULT G-flt Even though the generator speed is limited to N G As a result, the time required for the second stage Ph2 is reduced by the unfiltered upper limit torque ULT G Time t when using A A short time t compared to B It is as follows.

[0066] As mentioned above, the filtered upper limit torque ULT G-flt Second cryogenic start mode S using LT2 According to the above, the output power P of the battery 11 in an extremely low temperature environment is out Insufficient power supply is required, and simple motoring reduces the resonant frequency band B of the power generation system 10. RFEven if it is not possible to quickly pass through the resonant frequency band B, RF As a result, vibrations occurring in the power generation system 10 are reduced or suppressed.

[0067] Also, the generator rotation speed N G and engine speed N E is the resonant frequency band B of the power generation system 10 RF When the generator speed stagnates at N G and engine speed N E The phase difference between the two torques increases, and may exceed the allowable limits of the dampers and other components of the power transmission mechanism 16. However, as described above, the filtered upper limit torque ULT G-flt Second cryogenic start mode S using LT2 According to the RF Since the air can pass through the air, the occurrence of such problems is reduced or suppressed.

[0068] [Variations] Hereinafter, the second cryogenic start mode S according to the above embodiment will be described. LT2 A modification of the start control will be described.

[0069] In the above embodiment, in the rotation speed control of the generator 15, the resonant frequency band B RF Upper limit torque ULT filtered to reduce the G-flt However, the upper limit torque ULT G-flt When the actual power consumption by the generator 15 is calculated using the output power P out may be exceeded.

[0070] FIG. 12 shows the outputtable power P out 12A is a graph showing the actual power consumption by the generator 15 and the upper limit torque ULT G 12(B) shows the change in power consumption of the generator 15 when the upper limit torque ULT G-flt1 shows the change in power consumption of the generator 15 when the

[0071] As shown in FIG. 12(A), the rotation speed of the generator 15 is controlled by using an upper limit torque ULT G When the generator 15 is used, the power consumption of the generator 15 is approximately equal to the output power P out The output power P of the battery 11 changes within the following range. out On the other hand, as shown in FIG. 12(B), the rotational speed of the generator 15 is controlled by using the filtered upper limit torque ULT G-flt When the power consumption of the generator 15 is 1 / 2 times the output power P out For example, the generator speed N G When the change in the output power P is steep, or when the output power P is low due to an abnormality in the battery 11, out When the power consumption of the generator 15 suddenly changes, the power outputtable power P of the battery 11 out The power consumption of the generator 15 may exceed the output power P of the battery 11. out If the voltage exceeds this limit, it may cause deterioration or damage to the battery 11. Furthermore, a relay circuit (not shown) may cut off the power supply from the battery 11.

[0072] Therefore, as shown in the following equation (3), the outputtable power P of the battery 11 out A predetermined margin δ M Set the upper limit torque ULT G-flt It is desirable to calculate

[0073]

number

[0074] In this way, the output power P of the battery 11 out Margin δ M By setting the above, the power consumption of the generator 15 can be more reliably controlled to the outputtable power P of the battery 11. outThat is, the output power P of the battery 11 can be kept within the following range. out Margin δ M By setting the second cryogenic start mode S LT2 The start control of the resonant frequency band B is RF can be passed through quickly.

[0075] FIG. 13 shows the outputtable power P out The margin δ to be set for M As shown in FIG. 13, the margin δ M The upper limit torque ULT is calculated by setting G-flt is the unfiltered upper limit torque ULT G More roughly margin δ M Therefore, the power consumption of the generator 15 is surely reduced by the amount of the outputtable power P of the battery 11. out It will be within the range.

[0076] In this modification, the margin δ M is a predetermined fixed value, but the margin δ M is the temperature of the engine 14 (engine oil temperature T oil As described above, the lower the temperature of the engine 14, the lower the required power NP out increases exponentially, the lower the temperature of the engine 14, the greater the actual power consumption of the generator 15. Therefore, the margin δ M is set to a variable value according to the temperature of the engine 14, and is set to increase exponentially as the temperature of the engine 14 decreases, thereby ensuring safety regardless of the temperature of the engine 14.

[0077] As described above, the start-up control method for the power generation system according to the embodiment is a method for controlling the start-up of the power generation system (10) including the internal combustion engine (14) as a power source, the generator (15), and the power transmission mechanism (16) for transmitting power between the internal combustion engine (14) and the generator (15), by driving the generator (15) with electric power supplied from the battery (11) and controlling the rotation speed (N G ) to the target rotation speed (N G * In this power generation system start-up control method, the rotation speed is controlled to match the outputtable power (P out ) is obtained, and the rotation speed (N G ) is acquired. Also, the rotation speed (N G ) and the resonance frequency band (B RF ) is filtered to reduce the rotational speed (N G-flt ) and available output power (P out ) and based on this, the torque (T G ) is the upper limit of the upper limit torque (ULT G-flt ) is calculated. Then, this upper limit torque (ULT G-flt The rotation speed control is performed under the restriction of

[0078] In this way, the upper limit torque ULT G-flt By executing the start control of the second cryogenic temperature start mode using out Even if there is a shortage of RF As a result, the vibrations occurring in the power generation system 10 are reduced or suppressed. RF By allowing the flow of the fluid to pass through, the occurrence of problems such as exceeding the allowable limits of the dampers and the like that constitute the power transmission mechanism 16 is reduced or suppressed.

[0079] In particular, in the start-up control method for the power generation system according to the above-described modified example, the available output power (P out ) with margin (δ M ) and set the filtered generator (15) rotation speed (N G-flt ) and available output power (P out ) to margin (δ M ) and subtract the deviation (P out -δ M ) and the upper limit torque (ULT G-flt In this way, the available output power P of the battery 11 is calculated. out Margin δ M By setting the above, the power consumption of the generator 15 is set to the outputtable power P of the battery 11. out In other words, the start-up control method for the power generation system according to the above modification ensures safety and quickly reaches the resonant frequency band B RF can be passed through.

[0080] In the start-up control method for the power generation system according to the above modification, the margin (δ M ) is a variable value depending on the temperature of the internal combustion engine (14). M is a variable value depending on the temperature of the internal combustion engine (14), thereby ensuring particular safety regardless of the specific temperature of the engine (14).

[0081] The start-up control method for the power generation system according to the above-described embodiment and modification includes at least a step of controlling the temperature of the internal combustion engine (14) to a predetermined temperature (TH oil ) or less, and the output power (P out ) is the power (NP) required to drive the generator (15). out ), the filtered upper limit torque (ULT G-flt ) is limited by the second cryogenic start mode S. LT2 In the filtered upper limit torque ULT G-flt As described above, the second cryogenic start mode SLT2 In particular, the control period of the second stage Ph2 is prolonged and the generator rotation speed N G and engine speed N E is the resonant frequency band B RF Therefore, as mentioned above, the rotation speed control is G-flt In other words, the start control method for the power generation system according to the above embodiment and modified example is executed under the restriction of the second cryogenic start mode S LT2 It is particularly effective when implemented in

[0082] In the start control method for the power generation system according to the above embodiment and the modified example, the target rotation speed (N G * ) is the resonant frequency band (B RF ) is a lower rotation speed than the first target rotation speed (N G1 * ), and the internal combustion engine (14) is ignited. After this ignition, when the internal combustion engine (14) starts to output torque by combustion, the target rotation speed (N G * ) is the first target rotation speed (N G1 * ) to the rotation speed (N G ) into the resonant frequency band (B RF ) to a higher RPM than the second target RPM (N G2 * ) and at least the target rotation speed (N G * ) is the second target rotation speed (N G2 * ), the filtered upper limit torque (ULT G-flt ) The rotation speed control is performed under the restriction of at least the second cryogenic start mode S LT2 In the second stage Ph2 control, the filtered upper limit torque ULT G-flt As mentioned above, the second cryogenic start mode S LT2The second stage, Ph2, is the unfiltered upper limit torque ULT G The generator torque T G is limited, and the generator rotation speed N G and engine speed N E is the resonant frequency band B RF Therefore, as described above, in at least the second stage Ph2 control, the filtered upper limit torque ULT G-flt By using the generator rotation speed N G and engine speed N E is the resonant frequency band B RF That is, the start control method for the power generation system according to the above embodiment and the modified example is particularly effective in the second cryogenic start mode S LT2 It is most effective when implemented in the second phase, Phase 2.

[0083] The start control device of the power generation system according to the above embodiment and modified example drives the generator (15) with electric power supplied from the battery (11) and controls the rotation speed (N G ) to the target rotation speed (N G * The controller (13) controls the number of revolutions of the battery (11) to match the available power output (P out ) and the rotation speed (N G ) and the controller (13) acquires the rotation speed (N G ) and the resonance frequency band (B RF ) component. Furthermore, the controller (13) performs filtering to reduce the filtered rotation speed (N G-flt ) and available output power (P out ) and based on this, the torque (T G) is the upper limit of the upper limit torque (ULT G-flt Then, the controller (13) calculates the upper limit torque (ULT G-flt ) to execute the rotation speed control.

[0084] The above describes embodiments of the present invention, but the configurations described in the above embodiments and each modified example only show some of the application examples of the present invention and are not intended to limit the technical scope of the present invention.

Claims

1. A startup control method for a power generation system, the method comprising, when starting the power generation system including an internal combustion engine as a power source, a generator, and a power transmission mechanism that transmits power between the internal combustion engine and the generator, driving the generator with electric power supplied from a battery, and executing rotation speed control to match the rotation speed of the generator to a target rotation speed, obtain the available output power of the battery; The rotation speed is acquired, calculating a first upper limit torque, which is an upper limit value for the torque of the generator, based on the rotational speed and the available output power; performing a filtering process on the rotational speed to reduce components of a resonance frequency band of a spring mass system constituted by the internal combustion engine, the generator, and the power transmission mechanism; calculating a second upper limit torque, which is an upper limit value for the torque of the generator, based on the filtered rotational speed and the available output power; when the temperature of the internal combustion engine is higher than a predetermined temperature, or when the available output power is equal to or greater than the power required to drive the generator, the rotation speed control is performed under the restriction of the first upper limit torque; when the temperature of the internal combustion engine is equal to or lower than the predetermined temperature and the available output power is smaller than the power required to drive the generator, the rotation speed control is executed under the restriction of the second upper limit torque. A method for controlling the start-up of a power generation system.

2. 2. A startup control method for a power generation system according to claim 1, comprising: setting a margin for the available output power; calculating the second upper limit torque based on the filtered rotation speed and a deviation obtained by subtracting the margin from the available output power; A method for controlling the start-up of a power generation system.

3. 3. A startup control method for a power generation system according to claim 2, comprising: the margin is a variable value depending on the temperature of the internal combustion engine. A method for controlling the start-up of a power generation system.

4. 2. A startup control method for a power generation system according to claim 1, comprising: setting the target rotation speed to a first target rotation speed that is lower than the resonance frequency band; Ignite the internal combustion engine; after the ignition, when the internal combustion engine starts to output torque through combustion, the target rotation speed is set to a second target rotation speed that increases the rotation speed from the first target rotation speed to a rotation speed that is higher than the resonance frequency band; At least when the target rotation speed is set to the second target rotation speed, the rotation speed control is executed under the restriction of the second upper limit torque. A method for controlling the start-up of a power generation system.

5. A start control device for a power generation system, the start control device including a controller that drives the generator with electric power supplied from a battery when starting the power generation system including an internal combustion engine as a power source, a generator, and a power transmission mechanism that transmits power between the internal combustion engine and the generator, and that executes rotation speed control to match the rotation speed of the generator to a target rotation speed, The controller: obtain the available output power of the battery; The rotation speed is acquired, calculating a first upper limit torque, which is an upper limit value for the torque of the generator, based on the rotational speed and the available output power; performing a filtering process on the rotational speed to reduce components of a resonance frequency band of a spring mass system constituted by the internal combustion engine, the generator, and the power transmission mechanism; calculating a second upper limit torque, which is an upper limit value for the torque of the generator, based on the filtered rotational speed and the available output power; when the temperature of the internal combustion engine is higher than a predetermined temperature, or when the available output power is equal to or greater than the power required to drive the generator, the rotation speed control is performed under the restriction of the first upper limit torque; when the temperature of the internal combustion engine is equal to or lower than the predetermined temperature and the available output power is smaller than the power required to drive the generator, the rotation speed control is executed under the restriction of the second upper limit torque. A start control device for a power generation system configured as follows.

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