JP2019091544A - Control arrangement of plant for vehicle - Google Patents

Abstract

To control a plant for vehicle by using the components resulting from the frequency function values extracted efficiently from the output of the plant for vehicle, when generating an electric signal including the frequency function values as the components, by using the output of the plant for vehicle.SOLUTION: The second ECU of a control arrangement calculates the superposition sinewave value Usin of any one of frequencies Z-nZ (Hz), by a thinned-out method, by using the data group of one set of stored reference sinewave values Usin_b, executes AC superposition control by using the same, calculates a filter value Ifc_F by performing secondary low-pass filtering of the sampled current Ifc, during execution of AC superposition control, and controls a fuel cell device by using the filter value Ifc_F. The cut frequency of the secondary low-pass filtering is set to become higher for the higher frequency of the superposition sinewave value Usin.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a control device for a vehicle plant mounted on a vehicle.

  Conventionally, as a control device, the applicant has proposed one described in Patent Document 1. This control device carries out failure determination of the exhaust gas sensor provided in the exhaust passage of the vehicle, and executes the failure determination process shown in FIG. 3 of the same document.

  In this failure determination processing, when the predetermined detection condition is satisfied, the detection signal value KIDSIN is calculated by adding the offset value to the trigonometric function wave of the predetermined frequency, and this is multiplied by the basic fuel injection amount. As a result, the fuel injection amount IJN is calculated, and the fuel corresponding to the fuel injection amount IJN is supplied to the engine via the injector.

  Then, the detection value KACT of the exhaust gas sensor is subjected to band pass filter processing to calculate the filter value KACT_F, and the absolute value KACT_FA is integrated to calculate the integral value LAF_DLYP. When the integrated value LAF_DLYP is equal to or greater than a predetermined value LAF_DLYP_OK, it is determined that the exhaust gas sensor is not at fault, and otherwise, it is determined that the exhaust gas sensor is at fault.

Patent No. 4459566

  As a control device of a plant, an electric signal including as a component a periodic function value having one frequency selected from a plurality of different frequencies is generated using an output of the plant, and this electric signal is generated to generate There is one which detects the output of the plant at the same time, and controls the plant based on the detection result of the output. When the method of Patent Document 1 is applied to such a control device, if the pass band is inappropriate because band pass filtering is applied to the detection result of the output, the periodic function value is used. The resulting components can not be extracted efficiently, which may reduce the control accuracy of the plant.

  The present invention has been made to solve the above problems, and is efficiently extracted from the output of the vehicle plant in the case of generating an electrical signal including the periodic function value as a component using the output of the vehicle plant. An object of the present invention is to provide a control apparatus for a vehicle plant that can control a vehicle plant using components derived from periodic function values, and can thereby improve the control accuracy of the plant.

  In order to achieve the above object, the invention according to claim 1 is a control device 1 of a plant (fuel cell device 10) for a vehicle mounted on a vehicle 3, which is provided with a predetermined reference frequency (Z Hz) Using a storage unit (second ECU 21 and reference sine wave value calculation unit 50) for storing sets of reference periodic function value data groups, and using one set of reference periodic function value data groups stored in the storage unit, an integer of the reference frequency While being capable of generating n periodic function values each having n (n is an integer) different frequencies from each other, it is possible to select any one of the n periodic function values as a periodic function value It is electrically connected to the periodic function value generation means (the second ECU 21 and the reference sine wave value calculation unit 50) selectively generated as (reference sine wave value Usin_b), and to the vehicle plant (fuel cell device 10). Plant (fuel Electric signal generating means (converter 22) for generating an electric signal including the selected periodic function value as a component using the output (current Ifc) of the pond device 10), and the plant for a vehicle when the electric signal is generated Sampling means (the second ECU 21 and the current sensor 23) for sampling the electric signal value (current Ifc) output from (the fuel cell device 10) at a predetermined sampling period (control period ΔTk) and the electric signal value (current Ifc) Filter value calculation means (the second ECU 21 and the filter value calculation unit 52) for calculating the filter value Ifc_F by applying predetermined filter processing (equations (1) to (3)) and the filter value Ifc_F First control means (second ECU 21) for controlling the plant (fuel cell device 10), and the predetermined filter processing An upper limit value of the predetermined pass band is set to have a higher frequency as the frequency of the selection periodic function value is higher.

  According to this vehicle plant control device, using a set of reference periodic function value data groups stored in the storage means, n different (n is an integer) frequencies of integer multiples of the reference frequency are respectively provided. While being able to generate n periodic function values, any one of the n periodic function values is selectively generated as the selected periodic function value. Then, an electric signal generation unit electrically connected to the vehicle plant generates an electric signal including the generated selection periodic function value as a component using the output of the vehicle plant, and an electric signal is generated. At the same time, the electric signal value output from the vehicle plant is sampled at a predetermined sampling period. Further, the electric signal value is subjected to predetermined filtering to calculate a filter value, and the vehicle plant is controlled using the filter value. In this case, the predetermined filtering process is configured to have a predetermined passband, and the upper limit value of the predetermined passband is set to be higher as the frequency of the selection periodic function value is higher. Therefore, it is possible to obtain the filter value as a value efficiently extracted from the electric signal value only the component attributed to the selection periodic function value while appropriately cutting the noise component. Therefore, control accuracy can be improved by controlling the vehicle plant using such filter values.

  According to the second aspect of the present invention, in the control device 1 of the vehicle plant (fuel cell device 10) according to the first aspect, the periodic function value generation means uses one set of reference periodic function value data group as it is. Generating one of the n periodic function values and periodically thinning out a set of reference periodic function value data groups by n-1 periodic function values other than one periodic function value It is characterized by generating by using.

  According to this vehicle plant control device, by using one set of reference periodic function value data group as it is, one of the n periodic function values is generated, and the one other than one periodic function value is generated. Since the n-1 periodic function values of are generated by periodically thinning out and using the reference periodic function value data group, it is possible to reduce the operation load when generating n periodic function values. . In addition to this, the storage means only needs to have a capacity capable of storing only one set of reference periodic function value data groups, so that the storage capacity can be reduced. Furthermore, in the case of porting functions to another control device, portability can be enhanced because porting can be easily performed by avoiding porting of a large amount of data, thereby enhancing its versatility. As described above, when controlling a vehicle plant, it is possible to enhance versatility and to use periodic function values having n different frequencies from each other while suppressing increases in calculation load and storage capacity, and as a result, the commercial property It can be improved.

  In the invention according to claim 3, in the control device 1 of the vehicle plant (fuel cell device 10) according to claim 1, the periodic function value (reference sine wave value Usin_b) is configured as a sine function value or a cosine function value. And the sampling means samples the AC signal value (current Ifc) as the electric signal value, and acquires the amplitude Aac of the AC signal value based on the gradient value (gradient DIfc) representing the gradient of the AC signal value. (The second ECU 21 and the amplitude calculation unit 53) and the second control means (the second ECU 21) for controlling the vehicle plant (the fuel cell apparatus 10) using the amplitude Aac, and the amplitude acquisition means has the slope value In the gradient DIfc represented by the gradient DIfc having the same sign, the sign D is inverted after the sign is inverted from the continued state after the predetermined number of times (judgment count Njud) or more, When fc continues for a predetermined number of times (judgment count Njud) or more, one of the maximum value (maximum current value Ifc_max) and the minimum value (minimum current value Ifc_min) based on the inversion direction of the sign is the filter value Ifc_F at sign inversion. The amplitude Aac is acquired as the difference between the maximum value (maximum current value Ifc_max) and the minimum value (minimum current value Ifc_min), and the frequency of the selected periodic function value is a predetermined number of times (determination number Njud). The higher the value, the smaller the value set.

  According to this vehicle plant control device, the amplitude of the AC signal value is obtained based on the gradient value representing the gradient of the AC signal value, and the vehicle plant is controlled using this amplitude. In this case, in the gradient represented by the gradient value, the AC signal value at the time of sign inversion when the sign inversion is continued for the predetermined number of times or more after the sign is inverted after the slope of the same code continues for a predetermined number of times or more Is set as one of the maximum value and the minimum value based on the inversion direction of the code, and the amplitude is acquired as the difference between the maximum value and the minimum value, and the predetermined number of times indicates that the frequency of the selection periodic function value is higher Since the value is set to a smaller value, the amplitude can be accurately obtained according to the frequency of the selection periodic function value. Therefore, control accuracy can be further improved by controlling the vehicle plant using such an amplitude.

  In the invention according to claim 4, in the control apparatus 1 for a vehicle plant according to claim 1, the vehicle plant is a fuel cell device 10, and the electrical signal generation means generates an alternating current signal as an electrical signal, The fuel cell apparatus 10 is controlled so that the impedance acquisition means (the second ECU 21 and steps 50 to 53) for acquiring the impedance Zfc of the fuel cell stack when an AC signal is generated, and the impedance Zfc becomes a predetermined target value Zfc_cmd. It further has the 3rd control means (1st ECU11, step 60-63) to control, It is characterized by the above-mentioned.

  According to this vehicle plant control device, since the impedance of the fuel cell stack when the AC signal as the electric signal is generated is acquired, one of the n periodic function values is one. An impedance can be obtained using the selection periodic function value. Therefore, by appropriately selecting the selection cycle function value, the acquisition accuracy of the impedance can be improved, and the control accuracy of the fuel cell device can be improved.

  In the invention according to claim 5, in the control apparatus 1 for a vehicle plant according to claim 4, the impedance acquiring means acquires a plurality of impedances at a plurality of portions of the fuel cell stack when an alternating current signal is generated. It is characterized by

  According to this vehicle plant control device, since a plurality of impedances are obtained at a plurality of portions of the fuel cell stack when an alternating current signal is generated, a failure occurs in any of the plurality of portions of the fuel cell stack If this is the case, it is possible to appropriately identify the failure occurrence point using a plurality of impedances.

FIG. 1 is a view schematically showing a configuration of a control device according to an embodiment of the present invention and a drive system of a vehicle having a fuel cell device to which the control device is applied as a motive power source. It is a block diagram which shows the electric constitution of a control apparatus. It is a block diagram which shows the functional structure of a control apparatus. (A) A diagram showing an example of a reference sine wave value map, and (b) A diagram showing an example of a reference sine wave value Usin_b generated when the frequency command value Fr_cmd = 1. It is a figure which shows an example of reference | standard sine wave value Usin_b produced | generated when frequency instruction value Fr_cmd = 2. It is a table showing a method of reading data from the reference sine wave value map when frequency command value Fr_cmd = 1 to n. It is a figure which shows an example of the map used for calculation of time constant Td. It is a figure for demonstrating the calculation principle of amplitude Aac. It is a figure which shows an example of the map used for calculation of the determination frequency Njud. It is a flow chart which shows exchange superimposition control processing. It is a flow chart which shows superposition sine wave value calculation processing. It is a flow chart which shows amplitude calculation processing. It is a flow chart which shows impedance calculation processing. It is a flowchart which shows FC humidification control processing.

  Hereinafter, a control apparatus for a vehicle plant according to an embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, the control device 1 controls a fuel cell device (referred to as “FC” in the figure) 10 as a plant for a vehicle, and the fuel cell device 10 is a power source for the vehicle 3. It is mounted as. In addition, the structure shown with a broken line in FIG. 1 is a mechanical connection structure.

  The fuel cell apparatus 10 includes a first ECU 11 shown in FIG. 2 in addition to a fuel cell stack, a hydrogen tank, a hydrogen pump, an air pump (all not shown) and the like.

  The first ECU 11 is configured by a microcomputer including a CPU, a RAM, a ROM, an I / O interface (all not shown), etc., and drives the hydrogen pump to drive the hydrogen in the hydrogen tank and the air pump. By driving, air is supplied to the fuel cell stack. Thereby, the water content or impedance in the fuel cell stack is controlled.

  Further, the first ECU 11 calculates control data such as a frequency command value Fr_cmd described later according to the operation state of the vehicle 3 and outputs the calculation result to the second ECU 21 described later.

  The fuel cell stack is formed by stacking a large number of cells, and takes in hydrogen supplied from a hydrogen pump and oxygen in the air, and performs a power generation operation by chemically reacting them. The electric power generated by the fuel cell stack is supplied to the battery 31 or the electric motor 41 via an FC-VCU 20 described later.

  The vehicle 3 includes, in addition to the fuel cell device 10, an FC-VCU 20, a VCU 30, a battery 31, a PDU 40, an electric motor 41, and the like.

  The FC-VCU 20 includes a second ECU 21 and a converter 22 as shown in FIG. The second ECU 21 is configured by a microcomputer similar to the first ECU 11, and controls the generated power of the fuel cell device 10 by driving the converter 22 as described later. In the present embodiment, the second ECU 21 corresponds to storage means, periodic function value generation means, sampling means, first control means, second control means, filter value calculation means, impedance acquisition means, and amplitude acquisition means.

  The converter 22 (electric signal generation means) is of multi-phase converter type, includes many conversion units for converting the electric power generated by the fuel cell device 10 into voltage, and controls on / off of the switching elements of each conversion unit. The generated voltage of the fuel cell device 10 is boosted by (duty control).

  As shown in FIG. 1, a current sensor 23 and a voltage sensor 24 are provided between the fuel cell device 10 and the FC-VCU 20. The current sensor 23 detects an alternating current Ifc flowing from the fuel cell device 10 to the FC-VCU 20, and the voltage sensor 24 detects an output voltage Vfc of the fuel cell device 10. The current Ifc and the voltage Vfc are input to the second ECU 21 via the converter 22. In the present embodiment, the current sensor 23 corresponds to the sampling means, and the current Ifc corresponds to the output of the vehicle plant, the electric signal value, and the AC signal value.

  The second ECU 21 calculates the impedance Zfc of the fuel cell stack based on the current Ifc and the voltage Vfc by a method to be described later, and outputs the calculation result to the first ECU 11. Further, as described later, the second ECU 21 calculates a control input signal value Uduty to be supplied to the converter 22 based on the control data input from the first ECU 11.

  The VCU 30 incorporates a DC / DC converter, and controls transfer of power between the fuel cell device 10 and the electric motor 41 and the battery 31 while executing the step-up / step-down operation. Specifically, the generated electric power of the fuel cell device 10 and the regenerated electric power of the electric motor 41 are stepped down to charge the battery 31, and the electric power of the battery 31 is boosted and supplied to the electric motor 41. The battery 31 is configured of a lithium ion battery type.

  Furthermore, the above-mentioned PDU 40 incorporates an inverter, and converts the direct current from the fuel cell device 10 and / or the battery 31 into an alternating current and supplies it to the electric motor 41 at the time of powering control of the electric motor 41. On the other hand, during regenerative control of the electric motor 41 while the vehicle 3 is decelerating, the alternating current generated by the electric motor 41 is converted into direct current and the battery 31 is charged.

  Further, the electric motor 41 is mechanically connected to the drive wheels 5 and 5 via the transmission 4, and when the electric motor 41 is under powering control, the power of the electric motor 41 is the drive wheels 5 and 5. Transmitted to Thus, the vehicle 3 travels.

  Next, the functional configuration of the control device 1 of the present embodiment will be described with reference to FIG. As shown in FIG. 3, the control device 1 includes a reference sine wave value calculation unit 50, a superimposed amplitude calculation unit 51, a filter value calculation unit 52, an amplitude calculation unit 53, an amplitude FB controller 54, a voltage FB controller 55, and a duty signal. A value calculation unit 56, a multiplier 57, two subtracters 58 and 59, and an adder 60 are provided, and these elements 50 to 60 are all configured by the second ECU 21.

  First, in the reference sine wave value calculation unit 50, the reference sine wave value map stored in the ROM of the second ECU 21 is calculated based on the frequency command value Fr_cmd included in the control data from the first ECU 11 by the method described below. The reference sine wave value Usin_b is calculated using this. The frequency command value Fr_cmd is selectively set to any one of values 1 to n (n is an integer) in the first ECU 11. In the present embodiment, the reference sine wave value calculation unit 50 corresponds to the storage means and the periodic function value generation means, and the reference sine wave value Usin_b corresponds to the periodic function value and the selection periodic function value.

  The data of this reference sine wave value map is set, for example, as shown in FIG. 4 (a). In the case of FIG. 4A, the numbers of data No. (= 1 to 17) and data amplitude values (= −4 to +4) are set to be smaller than the actual values for easy understanding. .

  As shown in FIG. 4A, in this reference sine wave value map, only one set of data group is set, and when the frequency command value Fr_cmd = 1, at a predetermined control cycle ΔTk (for example, 10 msec), The map data of the reference sine wave is read out as it is. Accordingly, as shown in FIG. 4B, when Fr_cmd = 1, a reference sine wave of a predetermined frequency Z (Hz) having the reference sine wave value Usin_b as a component is generated.

  On the other hand, when the frequency command value Fr_cmd = 2, the value of the odd data No. (1, 3, 5...) Is read out at the predetermined control period ΔTk, whereby the diagram as shown in FIG. A reference sine wave whose component is only the data of the reference sine wave value Usin_b of the white circle of 4 (b) is generated. In this case, the reference sine wave is generated at a frequency of 2Z (Hz) by reading out one piece of map data in FIG. 4A. That is, when Fr_cmd = 2, a reference sine wave is generated at a frequency twice that of Fr_cmd = 1 by periodically thinning out the data group of FIG. 4A one by one.

  Further, when the frequency command value Fr_cmd = 3, the reference sine wave is generated at a frequency of 3Z (Hz) by periodically reading out the map data of FIG. 4A with two skipping. That is, when Fr_cmd = 3, a reference sine wave having a frequency three times that of Fr_cmd = 1 is generated from the data group of FIG.

  According to the above principle, when the frequency command value Fr_cmd = n, a reference sine wave generated by periodically reading out the reference sine wave value Usin_b from the map data of FIG. 4A by n-1 skipping. The frequency of is nZ (Hz). That is, when Fr_cmd = n, a reference sine wave with a frequency n times that of Fr_cmd = 1 is generated by periodically thinning out n−1 data groups from the data group of FIG. 4A. The above principle of generation of the reference sine wave is summarized in a table as shown in FIG.

  Further, in the superimposed amplitude calculation unit 51 described above, the superimposed amplitude A_map is obtained by searching a map not shown according to the boosting rate R, the current command value Ifc_cmd and the number of operating phases Nph included in the control data from the first ECU 11. Is calculated. In this case, boosting ratio R is a ratio at which generated voltage Vfc of fuel cell device 10 should be boosted, current command value Ifc_cmd corresponds to a target value of current Ifc, and operating phase number Nph is FC-VCU 20. It corresponds to the number of conversion units to be operated.

  Next, the multiplier 57 multiplies the reference sine wave value Usin_b by the superimposed amplitude A_map to calculate a superimposed sine wave value Usin (= Usin_b · A_map).

  On the other hand, in the filter value calculation unit 52 (filter value calculation means) described above, the filter value Ifc_F is calculated by the method described below using the current Ifc and the frequency command value Fr_cmd.

  Specifically, the filter value Ifc_F is calculated by the second-order low-pass filter algorithm shown in the following equations (1) to (3).

  Ts in the above equation (1) is a predetermined settling time. Further, Td is a time constant, and is calculated by searching a map shown in FIG. 7 according to the frequency command value Fr_cmd. Xα in the figure is a predetermined value, and as shown in the figure, the time constant Td is set to a smaller value in inverse proportion to the frequency command value Fr_cmd. This is due to the following reasons.

  That is, the filter value Ifc_F is calculated as a value obtained by cutting the high frequency noise component in the current Ifc using the above-described second-order low-pass filter algorithm in order to extract the component caused by the superimposed sine wave value Usin with high accuracy. On the other hand, since the superimposed sine wave value Usin is generated as a higher frequency value as the frequency command value Fr_cmd is larger, as described above, the cut frequency of the low pass filter is correspondingly higher. It is to set to. Further, as shown in FIG. 7, the processing can be simplified by mapping the time constant Td.

  Note that each discrete data with the symbol (k) in the above equations (1) to (3) indicates that it is data calculated (or sampled) in synchronization with the control period ΔTk described above, and the symbol k (K is a positive integer) represents the order of the calculation cycle of each discrete data. For example, symbol k indicates that the current value is calculated at the current calculation timing, and symbol k-1 indicates that the value is the previous value calculated at the previous calculation timing. The same applies to the following discrete data.

  Further, in the above-mentioned amplitude calculation unit 53 (amplitude acquisition means), the amplitude Aac is calculated by the method described below using the filter value Ifc_F and the frequency command value Fr_cmd.

First, the gradient DIfc (gradient value) of the filter value is calculated by the following equation (4) at the control period ΔTk described above, and the sign of the gradient DIfc is determined.

  Then, in the case where the sign of the gradient DIfc is inverted, it is determined whether or not the state of the same sign has continued for the judgment number of times Njud (predetermined number of times) or more before and after that. Then, when the sign of slope DIfc is inverted from positive to negative in the case where the state of the same sign continues more than the judgment number of times Njud before and after the inversion of the sign, the filter value Ifc_F at the time of the inversion is maximum current It is set to the value Ifc_max (maximum value).

  As the filter value Ifc_F at the time of inversion when calculating the maximum current value Ifc_max, the current value Ifc_F (k) and the previous value Ifc_F (k-1) in the calculation formula (4) of the slope DIfc when the sign is inverted Use the larger of the two. As the filter value Ifc_F at the time of inversion, an intermediate value between the current value Ifc_F (k) of the filter value and the previous value Ifc_F (k−1) may be used.

  On the other hand, conversely to the above, when the sign of the gradient DIfc is inverted from negative to positive, the filter value Ifc_F at the time of the inversion is set to the minimum current value Ifc_min (minimum value). As the filter value Ifc_F at the time of inversion when calculating the minimal current value Ifc_min, the current value Ifc_F (k) and the previous value Ifc_F (k-1) in the calculation formula (4) of the slope DIfc when the sign is inverted Use the smaller of the two. As the filter value Ifc_F at the time of inversion, an intermediate value between the current value Ifc_F (k) of the filter value and the previous value Ifc_F (k−1) may be used.

  Further, the determination number Njud described above is calculated by searching the map shown in FIG. 9 according to the frequency command value Fr_cmd. In the figure, ω is a predetermined value, and as shown in the figure, the number of times of determination Njud is set to a larger value in inverse proportion to the smaller frequency command value Fr_cmd. This is because, as described above, since the superimposed sine wave value Usin is generated as a lower frequency value as the frequency command value Fr_cmd is smaller, correspondingly, the number of determination times Njud is set to a larger number of times. It is.

Then, finally, the amplitude Aac is calculated by the following equation (5).

  Furthermore, in the subtractor 58 described above, the amplitude deviation DAac (= Aac_cmd-Aac) is calculated by subtracting the amplitude Aac from the target amplitude Aac_cmd. The target amplitude Aac_cmd is set in the first ECU 11 as control data in accordance with the operation state of the vehicle 3.

  Next, in the above-described amplitude FB controller 54, the amplitude FB input Ufb_a is calculated by a predetermined feedback control algorithm (for example, PID control algorithm) so that the amplitude deviation DAac converges to the value 0.

  On the other hand, in the subtractor 59 described above, the voltage deviation DVfc (= Vfc_cmd−Vfc) is calculated by subtracting the voltage Vfc from the target voltage Vfc_cmd. The target voltage Vfc_cmd is set in the first ECU 11 as control data in accordance with the operation state of the vehicle 3.

  Next, in the voltage FB controller 55 described above, the voltage FB input Ufb_v is calculated by a predetermined feedback control algorithm (for example, a PID control algorithm) so that the voltage deviation DVfc converges to the value 0.

Further, in the adder 60 described above, the final control input Uac is calculated by the following equation (6).

  Further, in the duty signal value calculation unit 56 described above, the duty signal value Uduty having the duty ratio corresponding to the final control input Uac is calculated by a method such as triangular wave comparison.

  Then, the duty signal value Uduty calculated as described above is supplied to the converter 22 so that feedback control is performed so that the generated voltage Vfc of the fuel cell device 10 becomes the target voltage Vfc_cmd, and the amplitude Aac of the current Ifc. Is feedback controlled so that the target amplitude Aac_cmd is obtained. Further, along with this, an alternating current (AC signal) in which an alternating current component including an superimposed sine wave value Usin as a component is superimposed on the current Ifc is generated by the converter 22 (AC superimposed). Then, the impedance Zfc of the fuel cell device 10 is calculated by the alternating current impedance method, as described later, based on the current Ifc and the voltage Vfc during the execution of the alternating current superposition.

  Next, alternating current superimposing control processing will be described with reference to FIG. In the alternating current superimposing control process, the duty signal value Uduty to be supplied to the converter 22 is calculated to generate an alternating current in which the alternating current component is superimposed on the current Ifc in the converter 22 for the purpose of calculating the impedance Zfc of the fuel cell device 10 And is executed by the second ECU 21 in the control cycle ΔTk described above. In the following description, various values calculated / sampled are stored in the RAM of the second ECU 21.

  As shown in the figure, first, at step 1 (abbreviated as “S1” in the figure, the same applies to the following), it is determined whether or not the execution condition of the AC superposition control process is satisfied. In this case, when the fuel cell apparatus 10 or the like is in an operation state capable of executing the AC superposition control process, it is determined that the execution condition of the AC superposition control process is satisfied. When the result of this determination is NO, this processing ends.

  On the other hand, when the determination result in step 1 is YES, the process proceeds to step 2 to execute superimposed sine wave calculation processing. The superimposed sine wave calculation process is to calculate the superimposed sine wave value Usin, and is specifically executed as shown in FIG.

  As shown in the figure, first, in step 20, as described above, the reference sine wave value Usin_b is calculated by reading out the data of the map of FIG. 4A according to the frequency command value Fr_cmd.

  Next, the process proceeds to step 21 and, as described above, the superimposed amplitude A_map is calculated by searching a map (not shown) according to the boosting rate R, the current command value Ifc_cmd and the number of operating phases Nph.

  Next, in step 22, the superimposed sine wave value Usin is set to the product of the reference sine wave value Usin_b and the superimposed amplitude A_map, and then the process is ended.

  Returning to FIG. 10, after calculating the superimposed sine wave value Usin as described above in step 2, the process proceeds to step 3, and it is determined whether or not it is the first control timing at which the execution condition of the alternating current superimposition control processing is satisfied. Determine.

  If the determination result in step 3 is YES and it is the first control timing that the execution condition of the AC superposition control processing is satisfied this time, the process proceeds to step 4 and the voltage FB input Ufb_v is set to the value 0.

  Next, in step 5, the amplitude FB input Ufb_a is set to the value 0. Then, in step 6, the final control input Uac is set to the sum of the superimposed sine wave value Usin and the voltage FB input Ufb_v and the amplitude FB input Ufb_a.

  Next, in step 7, according to the final control input Uac, the duty signal value Uduty is calculated by searching a map (not shown), and then the process is ended.

  On the other hand, if the result of the determination in step 3 described above is NO, and the execution condition of the AC superposition control processing is satisfied at the control timing before the previous time, the process proceeds to step 8 and the voltage deviation DVfc is set between the target voltage Vfc_cmd and the voltage Vfc. It sets to deviation (Vfc_cmd-Vfc).

  Next, the process proceeds to step 9, where the voltage FB input Ufb_v is calculated using a predetermined feedback control algorithm so that the voltage deviation DVfc converges to the value 0.

  Next, in step 10, it is determined whether or not the amplitude FB condition is established. In this case, after updating of the amplitude Aac is performed in step 42 described later, it is determined that the amplitude FB condition is satisfied. When the result of this determination is NO, as described above, after executing steps 5 to 7, the present processing is terminated.

  On the other hand, when the determination result in step 10 is YES and the amplitude FB condition is satisfied, the process proceeds to step 11, and the amplitude deviation DAac is set to the deviation (Aac_cmd-Aac) between the target amplitude Aac_cmd and the amplitude Aac.

  Next, in step 12, the amplitude FB input Ufb_a is calculated using a predetermined feedback control algorithm so that the amplitude deviation DAac converges to the value 0.

  Next, as described above, after executing steps 6 to 7, the present process is ended. As described above, when the AC superimposition control processing is executed, the duty signal value Uduty is supplied to the converter 22, whereby feedback control is performed so that the generated voltage Vfc of the fuel cell device 10 becomes the target voltage Vfc_cmd. The feedback control is performed such that the amplitude Aac of the current Ifc becomes the target amplitude Aac_cmd. Further, along with this, an alternating current in which an alternating current component including the superimposed sine wave value Usin as a component is superimposed on the current Ifc is generated by the converter 22 (AC superimposed).

  Next, the amplitude calculation process will be described with reference to FIG. This amplitude calculation process is for calculating the amplitude Aac of the current Ifc of the fuel cell device 10, and is executed by the second ECU 21 at the control period ΔTk described above.

  As shown in the figure, first, at step 30, it is determined whether or not an execution condition of the amplitude calculation process is satisfied. In this case, for example, when the above-described alternating current superposition control process is being executed and the elapsed time from the start of the execution is equal to or more than a predetermined value, it is determined that the execution condition of the amplitude calculation process is satisfied. When the result of this determination is NO, this processing ends.

  On the other hand, if the determination result in step 30 is YES and the execution condition of the amplitude calculation process is satisfied, the process proceeds to step 31 and it is determined whether the current control timing is the first control timing when the execution condition of the AC superposition control process is satisfied. Determine if If the answer to this question is negative (NO), that is, if the condition for executing the amplitude calculation process is satisfied at control timings before the previous time, then the process proceeds to step 34 described later.

  On the other hand, if the determination result in step 31 is YES, and it is the first control timing that the execution condition of the AC superposition control processing is satisfied this time, the process proceeds to step 32 and the above-described FIG. 7 is executed according to the frequency command value Fr_cmd. The time constant Td is calculated by searching the map.

  Next, the process proceeds to a step 33, where the number of judgments Njud is calculated by searching the above-mentioned map of FIG. 9 according to the frequency command value Fr_cmd.

  In step 34 following step 31 or 33 described above, the filter value Ifc_F is calculated by the above-described equations (1) to (3).

  Next, the process proceeds to a step 35, where the gradient DIfc is calculated by the above-mentioned equation (4).

Next, at step 36, it is judged if the condition for calculating the amplitude Aac holds. In this case, when all of the conditions (f1) to (f3) described below are satisfied, it is determined that the calculation condition of the amplitude Aac is satisfied.
(F1) The sign of the gradient DIfc is inverted.
(F2) In the calculation result before the sign inversion of the gradient DIfc, the calculated value of the same code must continuously exist for the judgment number of times Njud or more.
(F3) In the calculation results after the sign inversion of the gradient DIfc, the calculated value of the same sign must be present continuously for the number of judgments Njud or more.

  When the determination result of this step 36 is NO, this processing ends. On the other hand, if the determination result in step 36 is YES and the condition for calculating the amplitude Aac is satisfied, the process proceeds to step 37, and it is determined whether or not DIfc <0 is satisfied.

  If the answer to this question is affirmative (YES), ie if the gradient DIfc is a negative value, then the process proceeds to a step 38, where a maximum current value Ifc_max is calculated. Specifically, as described above, the maximum current value Ifc_max is set to the filter value Ifc_F at the time of sign inversion of the gradient DIfc.

  On the other hand, when the result of the determination in step 37 is NO and the gradient DIfc is a positive value, the process proceeds to step 39 and the local minimum current value Ifc_min is calculated. Specifically, as described above, the minimum current value Ifc_min is set to the filter value Ifc_F at the time of sign inversion of the gradient DIfc.

  In step 40 following step 38 or 39 described above, it is determined whether two values Ifc_max and Ifc_min have been calculated. When the result of this determination is NO, this processing ends.

  On the other hand, when the determination result in step 40 is YES and two values Ifc_max and Ifc_min have been calculated, the process proceeds to step 41, and the amplitude Aac is calculated by the above-mentioned equation (5).

  Next, in step 42, the amplitude Aac in the RAM is updated to the value calculated in step 41, and then this process ends.

  Next, the impedance calculation process will be described with reference to FIG. This impedance calculation process is for calculating the impedance Zfc of the fuel cell stack of the fuel cell device 10, and is executed by the second ECU 21 at the control period ΔTk described above.

  As shown in the figure, first, at step 50, it is judged whether or not the execution condition of the impedance calculation processing is satisfied. In this case, for example, when the above-described alternating current superposition control process is being executed and the elapsed time from the start of the execution is equal to or more than a predetermined value, it is determined that the execution condition of the amplitude calculation process is satisfied. When the result of this determination is NO, this processing ends.

  On the other hand, if the result of the determination in step 50 is YES, and the execution condition of the impedance calculation process is satisfied, the process proceeds to step 51 and the voltage Vfc is sampled.

  Next, at step 52, the current Ifc is sampled.

  In step 53 following step 52, after the impedance Zfc is calculated by the alternating current impedance method based on the sampled values of the voltage Vfc and the current Ifc, the present process is ended. The impedance Zfc calculated as described above is output from the second ECU 21 to the first ECU 11.

  Next, FC humidification control processing will be described with reference to FIG. The FC humidification control process controls the amount of hydrogen supplied to the fuel cell stack via the hydrogen pump and the amount of air supplied via the air pump, and is executed by the first ECU 11 in a predetermined control cycle. Be done.

  As shown in the figure, first, at step 60, it is judged if the execution condition of the FC humidification control processing is satisfied. Whether the execution condition of the FC humidification control process is satisfied or not is performed based on the operation states of the fuel cell device 10 and the vehicle 3. When the result of this determination is NO, this processing ends.

  On the other hand, if the result of the determination in step 60 is YES, and the condition for executing the FC humidification control process is satisfied, the process proceeds to step 61, and the impedance Zfc input from the second ECU 21 is read.

  Next, the process proceeds to step 62, where the humidification amount ADD_W is calculated such that the impedance Zfc becomes the target value Zfc_cmd.

  Next, at step 63, the humidification control process is executed. Specifically, a control input value is calculated by searching a map (not shown) according to the humidification amount ADD_W, and a control input signal corresponding to this is supplied to the hydrogen pump and the air pump. Thus, the fuel cell stack impedance Zfc is controlled to be the target value Zfc_cmd. As described above, after the humidification control process is performed in step 63, the present process is ended.

  As described above, according to the control device 1 of the present embodiment, in the reference sine wave value calculation unit 50, 1 of the reference sine wave value map (see FIG. 4A) stored in the ROM of the second ECU 21. Using n sets of data groups, n reference sine wave values Usin_b each having n different frequencies Z (Hz) to nZ (Hz) can be calculated, and a frequency command value Fr_cmd can be used. Based on this, a reference sine wave value Usin_b having a frequency of Z to nZ (Hz) is selectively calculated. At that time, when Fr_cmd = 1, the reference sine wave value Usin_b having the frequency of Z (Hz) is calculated by reading out the data of the reference sine wave value map as it is, and when Fr_cmd = 2 to n, FIG. The reference sine wave value Usin_b of 2 to n times the frequency when Fr_cmd = 1 is calculated by periodically thinning out 1 to n-1 each from the data group of (a), so n reference sine waves are generated. The calculation load at the time of calculating wave value Usin_b can be reduced.

  In addition to this, the ROM of the second ECU 21 only needs to have a capacity capable of storing only one set of data in the reference sine wave value map, so that the storage capacity can be reduced. Furthermore, when porting functions to another control device, portability can be enhanced because portability can be facilitated by not having to port a large amount of data. As described above, it is possible to improve the versatility and to calculate the reference sine wave value Usin_b having n different frequencies from each other while reducing the calculation load and the storage capacity, and to improve the productability.

  Further, during execution of the alternating current superimposing control process, the superimposed sine wave value Usin is calculated by multiplying the reference sine wave value Usin_b by the superimposed amplitude A_map, and the duty signal value Uduty calculated using this is supplied to the converter 22. As a result, an alternating current in which an alternating current component including the superimposed sine wave value Usin as a component is superimposed on the current Ifc is generated by the converter 22. Then, in that state, the current sensor 23 detects the current Ifc generated by the fuel cell device 10, and applies the secondary low-pass filter algorithm of Equations (1) to (3) to the current Ifc to obtain the filter value Ifc_F. Is calculated.

  In this case, since the time constant Td in the second order low pass filter algorithm is calculated by searching the above-mentioned map of FIG. 7 according to the frequency command value Fr_cmd, the cut frequency of the second order low pass filter is the frequency command value. As Fr_cmd is larger, the value is set to a higher frequency range. That is, since the cut frequency of the low-pass filter is set to a higher value as the frequency of the superimposed sine wave value Usin is higher, the filter value Ifc_F is attributed to the superimposed sine wave value Usin while appropriately cutting high frequency noise. Can be calculated as the value efficiently extracted from the current Ifc.

  Further, the maximum current value Ifc_max and the minimum current value Ifc_min of the filter value Ifc_F are calculated using the gradient DIfc of the filter value Ifc_F, and the amplitude Aac is calculated by subtracting the latter from the former. In this case, when the positive value gradient DIfc continues for more than the judgment number Njud and the gradient DIfc reverses to a negative value from the continued state, the negative value gradient DIfc continues for the judgment number Njud or more, and the sign of the gradient DIfc is inverted. The filter value Ifc_F is set as the maximum current value Ifc_max, and conversely to the above, since the gradient DIfc is inverted to a positive value from the state where the gradient DIfc of the negative value continues more than the judgment number Njud or more, the gradient DIfc of the positive value is When the number of times of determination Njud or more continues, the filter value Ifc_F at the time of sign inversion of the gradient DIfc is set to the minimum current value Ifc_min. This determination number Njud is set to a larger value as the frequency command value Fr_cmd is smaller, that is, as the frequency of the superimposed sine wave value Usin is lower, as shown in FIG. 9, so the frequency of the superimposed sine wave value Usin is set to Accordingly, the amplitude Aac can be obtained with high accuracy.

  Furthermore, the amplitude FB input Ufb_a is calculated so that the amplitude Aac becomes the target amplitude Aac_cmd, and the fuel cell device 10 is controlled using this. As described above, the fuel cell device 10 can be controlled using the filter value Ifc_F and the amplitude Aac which are accurately calculated, and the control accuracy can be improved.

  Further, since the impedance Zfc is calculated by selectively using the reference sine wave value Usin_b having any frequency from Z to nZ (Hz), it is suitable for calculation of the impedance Zfc as the reference sine wave value Usin_b. By selecting one having a frequency, it is possible to improve the calculation accuracy of the impedance Zfc. As a result, the control accuracy of the fuel cell device 10 can be improved.

  The embodiment is an example in which the fuel cell device 10 is used as a plant for vehicles, but the plant for vehicles of the present invention is not limited thereto, and may be one mounted in a vehicle. For example, a prime mover may be used as a vehicle plant.

  The embodiment is an example using the current Ifc or the impedance Zfc as a parameter representing the operating state of the vehicle plant, but the present invention is not limited thereto, and it is possible to represent the operating state of the vehicle plant Good. For example, when an internal combustion engine is used as a vehicle plant, the air-fuel ratio of the exhaust gas, generated torque or the like may be used.

  Furthermore, although the embodiment is an example using the second-order low-pass filter algorithm of Equations (1) to (3) as the predetermined filter processing, the predetermined filter processing of the present invention is not limited thereto, and a predetermined pass What is necessary is just to have a band. For example, a first order low pass filter algorithm or a band pass filter algorithm may be used. In this case, the cut frequency of the first order low pass filter algorithm or the upper limit value of the pass band of the band pass filter algorithm is larger as the frequency command value Fr_cmd is larger. Should be set to a higher frequency.

  On the other hand, although the embodiment is an example using the gradient DIfc as the gradient value, the gradient value of the present invention is not limited to this, and may be any gradient as long as it represents a gradient. For example, instead of the gradient DIfc, the deviation [Ifc_F (k) −Ifc_F (k−1)] between the current value and the previous value of the filter value may be used as the gradient value.

  Further, the gradient DIfc as the gradient value may be calculated by substituting the current Ifc instead of the filter value Ifc_F in the above-described equation (4).

  Furthermore, the embodiment is an example using the reference sine wave value Usin_b as the periodic function value, but instead of this, even if a cosine wave value whose phase is shifted by 90 ° with respect to the reference sine wave value Usin_b is used Good.

  On the other hand, the embodiment is an example in which the fuel cell device 10 is applied to a four-wheeled vehicle, but instead, the fuel cell device 10 may be applied to a vehicle having three or less wheels or a vehicle having five or more wheels .

  The embodiment is an example in which the impedance Zfc of the entire fuel cell stack of the fuel cell device 10 is calculated using one current sensor 23 and one voltage sensor 24. Instead of these, a plurality of current sensors may be used. And / or a plurality of voltage sensors or the like may be used to measure the impedance at multiple parts of the fuel cell stack.

  When configured in this manner, when a failure occurs in any of the plurality of portions of the fuel cell stack, it is possible to appropriately identify the failure occurrence location using a plurality of impedances. Also, for example, the FC humidification control process may be executed so that the average value of the impedances of a plurality of parts becomes the target value Zfc_cmd.

  Furthermore, in the embodiment, while the impedance Zfc is calculated by the second ECU 21 and the calculated Zfc is output to the first ECU 11, the impedance Zfc may be calculated by the first ECU 11 using the current Ifc and the generated voltage Vfc. In the embodiment, voltage feedback control (steps 6 and 7) using the generated voltage Vfc and the target voltage Vfc_cmd is performed, but current feedback control using the current IFc and the current command value Ifc_cmd may be performed.

1 control device 3 vehicle 10 fuel cell device (plant for vehicle)
11 1st ECU (3rd control means)
21 2nd ECU (storage means, periodic function value generation means, sampling means, filter value calculation means, first control means, amplitude acquisition means, second control means, impedance acquisition means)
22 Converter (electrical signal generation means)
23 Current sensor (sampling means)
50 Reference sine wave value calculation unit (storage means, periodic function value generation means)
52 Filter Value Calculator (Filter Value Calculator)
53 Amplitude calculation unit (amplitude acquisition means)
Usin_b Reference sine wave value (periodic function value, selected periodic function value)
ΔTk control cycle (sampling cycle)
Ifc (Vehicle plant output, electrical signal value, AC signal value)
Ifc_F Filter value DIfc Slope (slope value)
Njud judgment number (predetermined number)
Aac amplitude Ifc_max Maximum current value (maximum value)
Ifc_min Minimum current value (minimum value)
Zfc impedance Zfc_cmd target value

Claims (5)

A control device for a vehicle plant mounted on a vehicle, comprising:
Storage means for storing a set of reference periodic function value data having a predetermined reference frequency;
Using a set of reference periodic function value data groups stored in the storage means, generate n periodic function values each having n (n is an integer) different frequencies that are integer multiples of the reference frequency Periodic function value generation means configured to be capable of selectively generating any one of the n periodic function values as the selected periodic function value;
Electrical signal generation means electrically connected to the vehicle plant and generating an electrical signal including the selected periodic function value as a component using an output of the vehicle plant;
Sampling means for sampling the electric signal value output from the vehicle plant at a predetermined sampling period when the electric signal is generated;
Filter value calculation means for calculating a filter value by subjecting the electric signal value to a predetermined filter process;
First control means for controlling the vehicle plant using the filter value;
Equipped with
The predetermined filtering process is configured to have a predetermined passband, and the upper limit value of the predetermined passband is set to be higher as the frequency of the selection periodic function value is higher. Control device for a vehicle plant characterized in that.   The periodic function value generation means generates one of the n periodic function values by using the set of reference periodic function value data groups as it is, and at the same time, the periodic function values other than the one periodic function value 2. The control system of a vehicle plant according to claim 1, wherein n-1 periodic function values are generated by periodically thinning out and using the set of reference periodic function value data groups. The periodic function values are configured as sine function values or cosine function values,
The sampling means samples an AC signal value as the electric signal value,
Amplitude acquisition means for acquiring the amplitude of the AC signal value based on the gradient value representing the gradient of the AC signal value;
Second control means for controlling the vehicle plant using the amplitude;
In addition,
The amplitude acquiring unit is configured to, when, after the sign is inverted from the state in which the gradient of the same sign continues a predetermined number of times or more in the gradient represented by the gradient value, the gradient with the sign inversion continues a predetermined number of times or more The alternating signal value at the time of the sign inversion is set as one of the maximum value and the minimum value based on the direction of the sign inversion, and the amplitude is acquired as the difference between the maximum value and the minimum value The control system according to claim 1, wherein the number of times is set to a smaller value as the frequency of the selection cycle function value is higher. The vehicle plant is a fuel cell device,
The electrical signal generation means generates an alternating current signal as the electrical signal,
Impedance acquisition means for acquiring the impedance of the fuel cell stack when the AC signal is generated;
Third control means for controlling the fuel cell device such that the impedance becomes a predetermined target value;
The control apparatus of the plant for a vehicle according to claim 1, further comprising:   5. The control system according to claim 4, wherein the impedance acquiring unit acquires a plurality of the impedances at a plurality of portions of the fuel cell stack when the AC signal is generated.

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