PROPULSION CONTROL DEVICE

Abstract

Propulsion control device (1) which controls a power converter device (2) which supplies power to an electric motor (120) which drives an electric vehicle, wherein the propulsion control device (1) has a torque command calculation unit (30) for calculating a torque to be generated by the electric motor (120), wherein the moment command calculation unit (30) has: a target value calculation unit (32) for calculating a first moment (τ1) based on an operating instruction; and a rate-of-change control unit (34) for calculating and outputting a second moment (τ2), wherein the second moment (τ2) is a moment obtained by suppressing a rate of change of the first moment (τ1) with reference to a received voltage (V) r ) is obtained, whereby the received voltage (V r) is a voltage at which the power converter device (2) receives a power input, where, if the first moment (τ1) is a power path moment, the rate of change control unit (34) performs a control such that, the smaller the received voltage (V) r ) is, the smaller the rate of change of the second moment ((τ2) is.

Description

Area

[0001] The present invention relates to a propulsion control device that controls a power converter device that supplies power to an electric motor that drives an electric vehicle. background

[0002] Generally, electric vehicles are configured to draw power from an overhead line through a power collection device. This power is then used to drive an electric motor with a power converter, such as an inverter, thus propelling the electric vehicle. When a vehicle is used to exert a tractive force, known as power driving operation, the process takes place, consuming power supplied from the overhead line to drive the electric motor. When braking is applied to the vehicle, known as regenerative braking control, the process takes place, with the electric motor operating regeneratively to generate a braking force.

[0003] However, if the capacity of a substation supplying power to the overhead line is small, or if there is a large voltage drop in the overhead line due to a large distance between the substation and the electric vehicle, there are cases where the voltage received by the electric vehicle decreases and cases where the voltage received increases during the electric motor's power operation.

[0004] In the event of a noticeable decrease in the received voltage, the power converter may shut down due to low voltage, or other vehicles receiving power from the same overhead line may be unable to proceed. Therefore, if the received voltage decreases, a control mechanism is implemented to reduce the electric motor's torque and thus conserve power.

[0005] Conversely, if the received voltage increases, and if the increase is noticeable, various devices connected to the overhead line may shut down due to the overvoltage, or the devices may be damaged. Therefore, if the received voltage increases, a control mechanism is implemented to reduce the regenerative torque of the electric motor in order to limit the regenerative power output.

[0006] In JP 2002-252902 A1, as described below, a method is disclosed in which it is determined whether an input voltage of a converter satisfies a given voltage condition, and if it is determined that the input voltage of the converter does not satisfy the given voltage condition, an electric motor control current is set to a value corresponding to a filter capacitor voltage.

[0007] Publication JP H11-299 012 A shows that the deviation between the reference voltage of a filter capacitor and the actual voltage of the filter capacitor is processed by a proportional calculator and a first-order delay circuit. The processed value is subtracted from a first torque command value (the selected value of a torque command) to obtain a second torque command value. The gain factor of the proportional calculator is set according to the voltage of the filter capacitor and its rate of change. Furthermore, the time constant of the first-order delay circuit is set based on the rate of change of the filter capacitor voltage and its voltage deviation.

[0008] Publication JP H11-69880A describes an inverter controller consisting of a torque command correction section for voltage rise limitation and a rate-of-change limiting section. The voltage rise limitation torque command correction section outputs the capacitor DC voltage applied to a filter capacitor and the first torque command to control the DC voltage rise by reducing the regenerative torque as the DC voltage increases, using an operating torque command as its input. The rate-of-change limiting section limits the rate of change of the first torque command output by the voltage rise limitation torque command correction section and outputs the second torque command. Therefore, the inverter is controlled to modulate its output according to the voltage across a filter capacitor.It is therefore possible to limit DC voltage vibrations that arise when the torque current rate of change, which is to be changed according to the voltage of the filter capacitor, is large. Brief description of the technical problem

[0009] The output voltage of a generator located within or upstream of the substation is controlled to maintain a constant value, even when the load changes. Accordingly, a control system that maintains a constant substation output voltage perceives a change in the electric vehicle's operating state as a disturbance. If the electric vehicle's operating state is constant, the substation output voltage is also controlled to maintain a constant value. However, the more significant the change in the electric vehicle's driving or regenerative power, the greater the transient fluctuations in the substation's output voltage. This tendency becomes more pronounced the smaller the difference between the substation's power capacity and the power required by the electric vehicle.

[0010] It goes without saying that if the substation's output voltage fluctuates, the electric vehicle's received voltage will also fluctuate, necessitating increased control over reducing the electric vehicle's power-driving torque or regenerative torque. This means that, due to the influence of transient changes in the substation's output voltage, the electric vehicle will operate in a way that reduces torque more than necessary when initiating power-driving or regeneration.

[0011] In JP 2002-252902 A1, the amount of electrical power from the electric motor is controlled so that the power input voltage does not exceed a limit, and an operating state is achieved by allowing the power drive or regeneration to continue. However, the method in JP 2002-252902 A1 does not take into account the influence of the transient fluctuation of the substation's output voltage during torque ramp-up.

[0012] The present invention was made in view of the foregoing, and it is an object of the present invention to provide a propulsion control device which is capable of throttling an unnecessary amount of torque reduction while throttling a transient fluctuation of a received voltage of an electric vehicle. Solution to the problem

[0013] To solve the aforementioned problems and achieve the objective, propulsion control devices according to independent claims 1, 2, 3, 4 and 7 are provided in accordance with aspects of the present invention. Advantageous effects of the invention

[0014] The present invention achieves an effect of suppressing or throttling an unnecessary amount of torque reduction while suppressing or throttling a transient fluctuation of a received voltage of an electric vehicle. Brief description of the drawings Fig. Figure 1 shows a configuration diagram of a drive system for an electric vehicle which has a propulsion control device according to a first embodiment. Fig. Figure 2 shows a vector diagram illustrating the power input voltage and the received voltage in a steady state when a propulsion control device of the Fig. 1 power consumed. Fig. Figure 3 shows a vector diagram illustrating the power input voltage and the received voltage in a steady state when the thrust control device is in Fig. 1. Power regenerated. Fig. Figure 4 shows a configuration diagram of a drive system for an electric vehicle in a form different from the Fig. 1 shown. Fig. Figure 5 shows a configuration diagram of a drive system of an electric vehicle in a case where a rectifier is included in a configuration of Fig. 4 is considered part of a service supply. Fig. Figure 6 shows a configuration diagram of a drive system of an electric vehicle in a form different from those in the Fig. 1 and Fig. 5 shown. Fig. Figure 7 shows a block diagram representing a configuration of a moment instruction calculation unit in the first embodiment. Fig. Figure 8 shows a block diagram illustrating an example configuration of a rate-of-change control unit in the first embodiment. Fig. Figure 9 shows a diagram illustrating an example of a change quantity limit table, which is found in Fig. 8 is shown. Fig. Figure 10 shows a diagram to explain how the rate of change of a second moment changes under control of the rate of change control unit in a case where a first moment is a power driving torque. Fig. Figure 11 shows a diagram to explain how the rate of change of the second moment changes under the control of the rate of change control unit in a case where the first moment is a regenerative moment. Fig. Figure 12 shows a diagram to explain a function of a rate-of-change control unit in a second embodiment. Fig. Figure 13 shows a block diagram illustrating an example configuration of the rate of change control unit in the second embodiment. Fig. Figure 14 shows a diagram illustrating an example of a time constant table, which is in Fig. 13 is shown. Fig. Figure 15 shows a block diagram illustrating a configuration of a moment instruction calculation unit in a third embodiment. Fig. Figure 16 shows a diagram representing an example configuration of a limiter processing unit, which is located in Fig. 15 is shown. Fig. Figure 17 shows a diagram that presents an example of a power limiter table, which is in Fig. 16 is shown. Fig. Figure 18 shows a diagram to explain a state in which power limiting is enabled and a stabilization filter is switched between on and off. Fig. Figure 19 shows a block diagram representing a configuration of a moment instruction calculation unit in a fourth embodiment. Fig. Figure 20 shows a block diagram illustrating an example of a hardware configuration for implementing the moment instruction calculation unit in each of the first to fourth embodiments. Fig. Figure 21 shows a block diagram that illustrates another example of the hardware configuration for implementing the moment instruction calculation unit in each of the first to fourth embodiments. Description of embodiments

[0015] A propulsion control device according to embodiments of the present invention is described in detail below with reference to the drawings. The present invention is not limited to the following embodiments. First embodiment.

[0016] Fig. Figure 1 shows a configuration diagram of a drive system for an electric vehicle 100, which includes a propulsion control device 1 according to a first embodiment. The propulsion control device 1 is a device used for controlling the propulsion of an electric vehicle (not shown). Fig. 1 represents a power supply 110 which has a power supply device 106 which is capable of supplying alternating current power to the drive control device 1 and has an alternating current overhead line 108 for supplying the alternating current power generated by the power supply device 106 to the drive control device 1.

[0017] The propulsion control device 1 includes a power converter device 2, which receives the alternating current power supplied by the power supply 110 and uses the received power to supply power to an electric motor 120 to propel the electric vehicle. The power converter device 2 includes a rectifier 20, which rectifies an applied alternating current voltage to convert the alternating current voltage into a direct current voltage, and an inverter 22, which converts a direct current voltage output from the rectifier 20 into an alternating current voltage. Such a configuration, including the rectifier 20 and the inverter 22, is a general configuration of a propulsion control device installed in an electric vehicle.The electric motor 120, which is a load of the inverter 22, is driven by the output voltage of the inverter 22. The rectifier 20 can be either a self-commutated inverter or a diode rectifier.

[0018] The propulsion control device 1 further comprises a control unit 3, which controls the power converter device 2. The control unit 3 generates a pulse width modulation (PWM) signal for PWM control of the inverter 22.

[0019] If rectifier 20 is a self-commutated converter, control unit 3 can control rectifier 20. Documentation on PWM control is available, but a detailed description is omitted here.

[0020] The meaning of the in Fig. The symbols shown in section 1 are as follows. V f : Power supply voltage Vr : received voltage i L : Load current Z L : Impedance element

[0021] The power supply voltage V f is an output voltage of the power supply unit 106. The input voltage V r is a voltage received by the power converter device 2 via the AC overhead line 108. This means that the received voltage V r a voltage applied to the power converter device 2. The load current i L is a current that flows between the power supply 110 and the power converter device 2. The load current i L can be converted into a current flowing into the power converter device 2 from the power supply 110 or a current flowing from the power converter device 2 to the power supply 110.

[0022] The impedance element Z Lrepresents an aggregation of the impedance of the power supply equipment 106 and the impedance of the AC overhead line 108. An action of the impedance element Z L will be with reference to the Fig. 2 and Fig. 3 described.

[0023] Fig. Figure 2 shows a vector diagram indicating the power supply voltage V f and the received voltage V r in a steady state, indicating when the propulsion control device consumes 1 power. Fig. Figure 3 shows a vector diagram representing the power supply voltage V f and the receiving voltage V r in a steady state, indicating when the propulsion control device 1 regenerates power. In the Fig. 2 and Fig. 3 is a resistance component of the impedance element Z L denoted by "r" and a reactance component of the impedance element Z L is indicated by "x". This definition allows us to define the impedance element Z.L represented by using a symbol “j”, which represents an imaginary part, by a formula “Z L =r+jx".

[0024] When the propulsion control device 1 consumes power to drive the electric motor 120, the power supply voltage V f and the received voltage V r and the load current i L a in Fig. The ratio shown in section 2 is shown. Fig. 2. “θ”, see page 9, line 10, is called a load power factor angle. The load power factor angle θ is an angle determined by the received voltage V. r and the load current i L is formed. Additionally, in Fig. 2. “δ”, see page 9, line 12, is called a phase difference angle. The phase difference angle δ is an angle determined by the power supply voltage V. f and the received voltage V r is formed.

[0025] When the propulsion control device 1 consumes power to drive the electric motor 120, the received voltage V r smaller than the power supply voltage V f , because a voltage drop exists across an impedance element r+jx, and a voltage difference vector Δv, as shown in the figure, is generated. As shown in the figure, the voltage difference vector Δv can be divided into a component “ri L “ parallel to the load current i L and a component “xi” L “ orthogonal to the load current i” L be disassembled.

[0026] When the propulsion control device 1 accepts regenerative power from the electric motor 120, the power supply voltage V f , the received voltage V r and the load current i L one in Fig. The ratio shown in section 3 is also shown. At the same time, the received voltage V is measured. r greater than the power supply voltage Vf , because a voltage across the impedance element r+jx increases and a voltage difference vector Δv is generated as shown in the figure. This is similar to the case in Fig. 2. The stress difference vector Δv can be divided into a component “ri”. L “ parallel to the load current i L and a component “xi” L “ orthogonal to the load current i” L be disassembled.

[0027] The Fig. 2 and Fig. 3 represent the received voltage V r and the power supply voltage V f This is represented in the steady state when the propulsion control device 1 continuously consumes, regenerates, or generates a certain amount of power. During this steady state, alongside this steady state, a transient fluctuation occurs in the power supply voltage V. f as described in the section “Technical Problem”.

[0028] The reason why the power supply voltage V fThe transient fluctuations that occur when the load power changes can be described as follows.

[0029] First, in the present invention, although the form of the power supply 110 is not specifically limited, it is assumed that a rotary generator (not shown) is present on a power supply path. The generator is controlled so that the output voltage becomes constant by setting an excitation current of a field winding and by setting a machine input to the generator. However, there is a response delay even in a control system that keeps the output voltage constant; therefore, the output voltage fluctuates somewhat when the load power fluctuates. In addition, the steeper the fluctuation of the load power, the greater the fluctuation in the output voltage. Accordingly, when the power supply voltage V f As the voltage decreases, the received voltage V decreases. rThis occurs naturally. The present invention takes this phenomenon into account.

[0030] Fig. Figure 4 shows a configuration diagram of a drive system for an electric vehicle 100A in a form different from the one in Fig. 1 shown. Fig. Figure 4 shows a general configuration of an electric vehicle that utilizes a diesel-electric system. A power supply 110 A includes a diesel engine 111 and a generator 112, which generates AC power by utilizing the output of the diesel engine 111. The power from the generator 112 is supplied to the inverter 22 via the rectifier 20, and the electric motor 120 is driven by the inverter 22. Similar to an electric vehicle receiving power from an AC overhead line, the rectifier 20 can be either a self-commutated inverter or a diode rectifier. There is a difference in the degree of influence of the impedance element Z. L However, the one in Fig. 4. Configuration shown is similar to the one in Fig. 1 shown; therefore, a thrust control device 1A, which is in Fig. 4 shows an effect of applying the present invention similar to the propulsion control device 1, which is described in Fig. 1 is shown.

[0031] Fig. Figure 5 shows a configuration diagram of a drive system 100B for an electric vehicle in a case where the rectifier 20 is in a configuration of Fig. 4 is considered part of the power supply. In a case where the rectifier 20 is a diode rectifier 20B, the diode rectifier 20B can be considered part of a power supply 110B and included as a component of the power supply 110B, as shown in the figure. In that case, the received voltage V r for a propulsion control device 1B a DC voltage, but the received voltage V r changes depending on an input voltage V aof the diode rectifier 20B. Therefore, the propulsion control device 1B, which is in Fig. Figure 5 shows an effect of applying the present invention similar to the propulsion control device 1A, which is shown in Fig. 4 is shown.

[0032] Fig. Figure 6 shows a configuration diagram of a 100C drive system for an electric vehicle in one of the configurations shown in the Fig. 1 and Fig. The 5 depicted forms are of different shapes. Fig. Figure 6 represents a general configuration of an electric vehicle that travels by receiving a power supply from a DC overhead line, meaning that the electric vehicle is of a DC power supply type.

[0033] In a DC power supply case, a substation uses diodes to convert power received from an AC distribution system to DC power and supplies it to a power supply system. Therefore, as in Fig. As shown in Figure 6, a diode rectifier 20C, provided in the substation, can be considered a component of a power supply 110C. As a result, a power control device has a drive control device 1C, as shown in Figure 6. Fig. 6 shows the same configuration as the thrust control device 1B, which is shown in Fig. 5 is shown.

[0034] The received voltage V r The propulsion control device 1C requires a direct current voltage. The received voltage V r changes depending on the input voltage V a of the rectifier. Therefore, the propulsion control device 1C, which is in Fig. Figure 6 shows an effect of applying the present invention similar to the propulsion control device 1B, which is shown in Fig. Figure 5 is shown. However, the regenerative power of the electric vehicle does not flow to an AC power supply side as seen from the diode rectifier 20C. Therefore, the regenerative power of the electric vehicle is only consumed by other vehicles in the same section. Accordingly, in regenerative operation, there are no transient fluctuations in the power supply voltage V. f , which are taken into consideration in the present invention.

[0035] Fig. Figure 7 shows a block diagram illustrating a configuration of a torque command calculation unit 30 in the first embodiment. The torque command calculation unit 30 is a calculation unit configured within the control device 3. As shown in Fig. As shown in Figure 7, the moment command calculation unit 30 has a target value calculation unit 32 and a rate of change control unit 34.

[0036] The target value calculation unit 32 calculates an initial torque τ1, which is a target value of a torque to be generated by the electric motor 120, based on an operating command. The operating command contains vehicle information such as information about a gear selected by the driver, information about the vehicle load, and speed information about the electric vehicle. In many cases, a lighting characteristic is added to the initial torque τ1 output by the target value calculation unit 32 to prevent a torque shock. The lighting characteristic is a characteristic that increases or decreases an output depending on the time.In the present embodiment, as well as in other embodiments described below, a lighting characteristic is applied such that the first moment τ1 changes constantly over a period of time until it reaches the final target value from an initial value. Alternatively, a lighting characteristic can be applied such that the first moment τ1 changes at a constant rate of change over a period of time until it reaches the final target value from the initial value.

[0037] Based on the first moment τ1 and the recorded voltage V rThe rate-of-change control unit 34 calculates the second moment τ2, which is a moment obtained by suppressing or throttling the rate of change of the first moment τ1. The rate-of-change control unit 34 outputs the calculated second moment τ2 to the output side of the rate-of-change control unit 34. In the configuration of the Fig. 7. The second torque τ2, generated by the rate-of-change control unit 34, becomes a torque instruction τ*, generated by the torque instruction calculation unit 30. If the power supply is an alternating current, either an amplitude value of the AC voltage or an RMS value of the AC voltage can be used as the received voltage V. r can be used. The received voltage V r It can be a voltage that is subjected to a low-pass filtering process for the purpose of noise removal, or a voltage that is subjected to a moving average process.

[0038] As a method for controlling the torque of the electric motor 120, a vector control is widely used, in which a three-phase current value in a stationary coordinate system is decomposed into a d-axis current id, which is a current value of a flux axis component in a rotating orthogonal two-axis rotational coordinate system (i.e., a dq-axis coordinate system), and a q-axis current iq, which is a current value of a torque axis component in the dq-axis coordinate system, and then controlled. Since the configuration of the vector control is well known, a detailed description of it is omitted here. In the first embodiment, a current command value in the vector control is calculated based on the second torque τ2.

[0039] Fig. Figure 8 shows a block diagram illustrating an example configuration of the rate-of-change control unit 34 in the first embodiment. As shown in Fig. As shown in Figure 8, the rate of change control unit 34 comprises a differentiator 34a, a quantity of change limiting table 34b, a selection unit 34c, a delay unit 34d, and a summing unit 34e. What is meant by “z -1 The term written in the block of delay unit 34d means "a delay corresponding to one calculation cycle." This means, with respect to the second moment τ2, that delay unit 34d holds a value obtained in a previous calculation cycle; that is, it is a directly preceding value of the second moment τ2, and outputs this value to both the differentiator 34a and the summator 34e.

[0040] In the differentiator 34a, a deviation τ1-τ2' between the first moment τ1 and the immediately preceding value τ2' of the second moment τ2 is calculated and output to the selection unit 34c. The received voltage V rThe change quantity limit is taken from the change quantity limit table 34b and a moment change quantity limit value Δτ, which is a control input for limiting the change quantity in a moment, is obtained. The moment change quantity limit value Δτ is one limit value per calculation cycle.

[0041] In selection unit 34c, a smaller value of the deviation between the first moment τ1 and the immediately preceding value τ2' of the second moment τ2 and the moment change quantity limit value Δτ is selected and output to summing unit 34e. In summing unit 34e, the second moment τ2 is updated by adding the immediately preceding value τ2' of the second moment τ2 to the output of selection unit 34c, and the current second moment τ2 is output.

[0042] If the deviation τ1-τ2' between the first moment τ1 and the immediately preceding value τ2' of the second moment τ2 is smaller than the moment change quantity limit value Δτ in the selection unit 34c operation, the deviation τ1-τ2' is selected in selection unit 34c. Therefore, the first moment τ1, obtained by adding the immediately preceding value τ2' of the second moment τ2 to the deviation τ1-τ2', is output by the summer 34e.

[0043] On the other hand, if the deviation τ1-τ2' between the first moment τ1 and the immediately preceding value τ2' of the second moment τ2 is greater than the moment change quantity limit value Δτ in the operation of selection unit 34c, the moment change quantity limit value Δτ in selection unit 34c is selected. Therefore, a moment command that has a value obtained by adding the moment change quantity limit value Δτ to the immediately preceding value τ2' of the second moment τ2 is output by summer 34e.

[0044] Fig. Figure 9 shows a diagram illustrating an example of a change quantity limit table 34b, which is found in Fig. 8 is shown. On the left side of the Fig. Figure 9 shows a table in a case where a torque command is a power driving torque, as a graph. On the right side of the Fig. Figure 9 is a table in a case where the command moment is a regenerative moment, presented as a graph.

[0045] In the case where the first moment τ1 is a power driving torque, a fixing is carried out such that the smaller the received voltage V r The smaller the moment change quantity limit value Δτ is, as shown in the diagram on the left side of the Fig. 9 is shown. Specifically, in the case where the received voltage V r As the voltage decreases, a first fixed value Δτ1 is obtained until the received voltage V r a first threshold V th1 reached. When the received voltage V r below the first threshold V th1 As the torque falls, the limit value Δτ for the quantity of changes in torque is reduced until the received voltage V r a second threshold V th2 reached. The second threshold V th2is smaller than the first threshold V th1 Then, when the received voltage V r the second threshold V th2 Once this threshold is reached, a second fixed value Δτ2 is applied, which is a limit value for the quantity of moment changes at the second threshold V. th2 is, then received.

[0046] In the case where the first moment τ1 is a regenerative moment, a fixing is carried out such that the greater the received voltage V r The smaller the moment change quantity limit value Δτ is, as shown in the diagram on the right side of the Fig. 9 is shown. Specifically, in the case where the received voltage V r As the voltage increases, a third fixed value Δτ3 is obtained until the received voltage V r a third threshold V th3 reached. When the received voltage V r the third threshold V th3If the limit value for the amount of moment change is exceeded, it is reduced until the received voltage V is reached. r a fourth threshold V th4 reached. The fourth threshold V th4 is greater than the third threshold V th3 Then, when the received voltage V r the fourth threshold V th4 Once this threshold is reached, a fourth fixed value Δτ4 is applied, which is a limit value for the quantity of moment changes at the fourth threshold V. th4 is, then received.

[0047] Fig. Figure 10 shows a diagram to illustrate how the rate of change of the second torque τ2 changes under the control of the rate-of-change control unit 34 in the case where the first torque τ1 is a power-driving torque. Fig. 10 shows how the power torque changes, illustrated on the top page, and how the received voltage V changes. r Changes are displayed on the lower page.

[0048] Next, the waveforms will be discussed in Fig. 10 described. To simplify the description, it is assumed that the electric vehicle travels at a certain speed.

[0049] First, as in the upper part of the Fig. Figure 10 shows a power command AN at time t0. From time t0 to time t1, the power consumption and the received voltage V increase. r It decreases. However, at this point, the first moment τ1 and the second moment τ2 still coincide. The period from time t1 to time t2 is described below.

[0050] From time t2 to time t3, the power torque is controlled at a constant value. During this time, the power consumption becomes constant and the transient fluctuation of the power supply voltage V is reduced. f decreases; therefore, the received voltage V decreases. reasily as indicated by the waveform K2. A value of the steady state of the received voltage V r At that time, it depends on the impedance element Z. L and the size of the power consumption.

[0051] From time t3 to time t4, a control operation is carried out to halve a target torque value via the operating command. During this time, the power consumption decreases and the received voltage V decreases. r increases. Immediately after time t3, the power torque is output and the received voltage V is measured. r is smaller than the first threshold V th1 However, the rate of change of the first moment τ1 is not controlled, and the first moment τ1 and the second moment τ2 coincide. The same applies even after the received voltage V r the first threshold V th1The rate of change of the first moment τ1 is not controlled, and the first moment τ1 and the second moment τ2 coincide. The reason why the first moment τ1 and the second moment τ2 coincide is described as follows.

[0052] As described above, from time t3 to time t4, the control is carried out to halve the target torque value. In that case, according to the control system of the Fig. 7, the first moment τ1 is controlled first, thereby controlling the second moment τ2. Accordingly, the second moment τ2 changes in such a way that it follows the change in the first moment τ1. Therefore, in the configuration of Fig. 8 is an output of the differentiator 34a, which calculates a difference value between the first moment τ1 and the immediately preceding value τ2' of the second moment τ2, a negative value or zero. As in Fig. As shown in Figure 9, a value of zero or more is specified in the change quantity limit table 34b. Therefore, the difference between the first moment τ1 and the immediately preceding value τ2' of the second moment τ2, which is a negative value or zero, is selected as the output of the selection unit 34c and the output to the summing unit 34e. Then, in the summing unit 34e, the difference between the first moment τ1 and the immediately preceding value τ2' of the second moment τ2 is added to the immediately preceding value τ2' of the second moment τ2; thus, the first moment τ1 is output. As a result, the second moment τ2 coincides with the first moment τ1.

[0053] After time t4, the power consumption becomes constant, the transient fluctuation of the power supply voltage decreases, and the received voltage V r decreases slightly. Then the received voltage V is transmitted. r stable.

[0054] A waveform K1, indicated by a broken line from time t1 to time t2, is a waveform of the received voltage V. r In a case where the rate-of-change control unit 34, described above, is not present and a current command value in the vector control is calculated based on the first moment τ1, as shown in the figure, a transient decrease in the received voltage V occurs. r the change continues until it ends at time t2'. Accordingly, the waveform K2, represented by a solid line, is a waveform of the received voltage V. r in a case where a current command value is calculated in the vector control using the second moment τ2, which is the output of the rate of change control unit 34.

[0055] As shown in the figure, waveform K2 is a different curve than waveform K1 at time t1. Here, at time t1, the received voltage V reaches r the first threshold V th1 , as in the Fig. Figure 9 illustrates this. From time t1 to time t3, the rate of change of the second moment τ2 is controlled by the rate-of-change control unit 34. At that time, as is clearly understood by comparing waveform K2 and waveform K1, the decrease in the received voltage V r suppressed. Accordingly, by implementing a control such that the received voltage V is smaller. r The smaller the rate of change of the second moment τ2 during the power drive of the electric vehicle, the smaller it is possible to observe a decrease in the received voltage V. r to suppress it when the power delivery torque increases.

[0056] As described above, the rate-of-change control unit 34 in the first embodiment is configured such that, in a power-drive control scenario, if the first torque τ1 becomes equal to or less than the second torque τ2, or falls below the second torque τ2, the rate-of-change control of the first torque τ1 is not performed. The reason for this is as follows: When the power-drive torque decreases, the received voltage V decreases rtoo close to a normal voltage at no load or a nominal voltage; therefore, there is no particular interest in suppressing the rate of change of the torque command value. Another reason is that, from a safety standpoint, it is undesirable to suppress the rate of change of the first torque τ1, despite the fact that the first torque τ1 decreases, and a decrease in the torque generated in the electric motor 120 delays operation while the electric vehicle is under load. Accordingly, with a configuration in which the first torque τ1 becomes equal to or less than the second torque τ2, or falls below the second torque τ2, control of the rate of change of the first torque τ1 is not performed; the torque generated in the electric motor 120 can decrease rapidly during operation in which a command to reduce the load torque is issued by the operating command.

[0057] Fig. Figure 11 shows a diagram to illustrate how the rate of change of the second moment τ2 changes under the control of the rate-of-change control unit 34 in the case where the first moment τ1 is a regenerative moment. Fig. Figure 11 shows the upper part how the regenerative moment changes, and the lower part shows how the received voltage V changes. r changes. In the case where the first moment τ1 is a regenerative moment, as in the Fig. As shown in 11, the received voltage V changes. r in a direction opposite to that in the case of the performance run.

[0058] Next, the waveforms will be analyzed in Fig. 11 described. It is assumed that the electric vehicle is traveling at a certain speed in a similar manner to the time when the power driving torque is output.

[0059] First, as in the upper part of the Fig. Figure 11 shows that when the electric vehicle is driving around at a certain speed, a regeneration command is sent at time t0. From time t0 to time t1, the regenerative power increases, as does the received voltage V. r It increases. However, at this point, the first moment τ1 and the second moment τ2 still coincide. The time t1 to time t2 will be described later.

[0060] From time t2 to time t3, the regenerative torque is controlled with a constant value. During this time, the regenerative power becomes constant, and the transient fluctuation of the power supply voltage V is reduced. f falls; therefore, the received voltage V decreases. r something, as indicated by waveform K4. A steady-state value of the received voltage V r At that time, it depends on the impedance element Z. L The amount of regenerative power is determined.

[0061] From time t3 to time t4, a control operation is carried out to halve a target torque value via the operating command. At that time, the regenerative power decreases and the received voltage V decreases. r decreases. Immediately after time t3, the regenerative moment is output and the received voltage V is measured. r is greater than the third threshold V th3 , but the rate of change of the first moment τ1 is not controlled, and the first moment τ1 and the second moment τ2 coincide. The same applies after the received voltage V r below the third threshold V th3 The rate of change of the first moment τ1 is not controlled, and the first moment τ1 and the second moment τ2 coincide. The reason why the first moment τ1 and the second moment τ2 coincide is as follows.

[0062] As described above, from time t3 to time t4, the control is carried out to halve the target torque value. In that case, according to the control system of the Fig. 7, the first moment τ1 is controlled first, and thereby the second moment τ2 is controlled. Accordingly, the second moment τ2 changes in such a way that the change in the first moment τ1 follows. Therefore, in the configuration of Fig. 8, the output of the differentiator 34a, which calculates a difference value between the first moment τ1 and the immediately preceding value τ2' of the second moment τ2, is a negative value or zero. As in the Fig. As shown in Figure 9, a value of zero or more is specified in the change quantity limit table 34b. Therefore, the difference between the first moment τ1 and the immediately preceding value τ2' of the second moment τ2, which is a negative value or zero, is selected as the output of the selection unit 34c and output to the summing unit 34e. Then, in the summing unit 34e, the difference between the first moment τ1 and the immediately preceding value τ2' of the second moment τ2 is added to the immediately preceding value τ2' of the second moment τ2; thus, the first moment τ1 is output. As a result, the second moment τ2 and the first moment τ1 coincide.

[0063] After time t4, the regenerative power becomes constant, the transient fluctuation of the power supply voltage V f drops and the received voltage V r decreases slightly. Therefore, the received voltage V decreases. r stable.

[0064] A waveform K3, represented by a dashed line from time t1 to time t2, is a waveform of the recorded voltage V. r In a case where the rate-of-change control unit 34, described above, is not included, and a current command value in the vector control is calculated based on the first moment τ1, as shown in the figure, a transient increase in the received voltage V occurs. r the change continues until it ends at the first moment τ1 at time t2'. Accordingly, waveform K4 is indicated by a solid line and is a waveform of the received voltage V. rIn a case where a current command value is calculated in the vector control using the second moment τ2, which is an output of the rate-of-change control unit 34. As shown in the figure, waveform K4 is a curve different from waveform K1 at time t1. Here, at time t1, the received voltage V reaches r the third threshold V th3 , as in the Fig. Figure 9 is shown. From time t1 to time t3, the rate of change of the second moment τ2 is controlled by the rate-of-change control unit 34. At that time, as can be clearly seen by comparing waveform K4 and waveform K3, there is an increase in the received voltage V. r suppressed. Accordingly, by implementing a control such that the higher the received voltage V rThe smaller the rate of change in the second moment τ2 during the regeneration of the electric vehicle, the more likely it is that there will be an increase in the received voltage V. r to suppress it as the regeneration moment increases.

[0065] As described above, in the first embodiment, the rate-of-change control unit 34 is configured such that if the first torque τ1 becomes equal to or less than the second torque τ2, or if the second torque τ2 decreases in a case of regenerative control, the rate of change of the first torque τ1 is not controlled. The reason for this is as follows: When the regenerative torque decreases, the received voltage V decreases rand approaches the usual no-load voltage or a nominal voltage; therefore, there is no particular interest in suppressing the rate of change of the torque command value. Another reason is that, during the regeneration of the electric vehicle, the smaller the difference between the first torque τ1 and the second torque τ2, the more accurately the braking and stopping position of the electric vehicle can be set; and therefore, the duration during which the rate of change of the second torque τ2 is suppressed is desirable to be as short as possible.Accordingly, with a configuration in which, if the first torque τ1 becomes equal to or less than the second torque τ2 or falls below the second torque τ2, the control of the rate of change of the first torque τ1 is not carried out, and a torque generated in the electric motor 120 can be quickly reduced in an operation when a command to reduce the regenerative torque is issued by the operating command.

[0066] As described above, according to the propulsion control device of the first embodiment, the second moment is calculated by executing, on the basis of the received voltage V rIn an electric vehicle, a process of limiting the rate of change of the first torque, which is calculated based on the operating command, and the electric motor is controlled based on the second torque, is employed. Therefore, it is possible to suppress unnecessary torque reduction while mitigating transient fluctuations in the received voltage V. r the electric vehicle is suppressed. Second embodiment.

[0067] In a second embodiment, a further example configuration of the rate-of-change control unit 34 is described. Configurations of components other than the rate-of-change control unit 34 are the same as or equivalent to those of the first embodiment and are omitted here.

[0068] Fig. Figure 12 shows a diagram illustrating the function of a rate-of-change control unit in the second embodiment. In the second embodiment, a first-order delay filter is applied to a rate-of-change suppression function of the rate-of-change control unit. A transfer function G(s) of the first-order delay filter can be expressed by the following formula, where a time constant T f , which is a constant for determining a frequency response of a first-order delay filter process, is a parameter. [Formula 1] G(s)=11+sTf

[0069] Fig. 12 represents a waveform of a step response when the time constant T f is used as a parameter. As shown in the figure, the larger the time constant T fThe smaller the value, the smaller the increase in output. Accordingly, by applying the first-order delay filter to the first moment τ1 and making the time constant T variable. f depending on the perceived voltage V r The rate of change of the second moment τ2 can be controlled.

[0070] Next, if a discrete time duration is divided by T s If the input is denoted by u, the output by y, and the first-order delay filter is discretized, then the following differential equation holds. [Formula 2] y=z−1y+(Tf / Ts)z−1(u−y)

[0071] Fig. Figure 13 shows a block diagram illustrating an example configuration of a rate-of-change control unit 34A of a second embodiment. In the block diagram of the Fig. 13 is the input u in the differential equation (2) as above, replaced by the first moment τ1, and the output y therein is replaced by the second moment τ2. This means that the rate-of-change control unit 34A can be configured to have a delay unit 34A1, a time constant table 34A2, a differentiator 34A3, a divider 34A4, a multiplier 34A5, a summer 34A6, a delay unit 34A7, and a selection unit 34A8.

[0072] In the delay unit 34A1, an immediately preceding value τ1' of the first moment τ1 is selected at the time when the first moment τ1 is entered and is output to the differentiator 34A3. The time constant table 34A2 is configured such that the time constant T f according to the received voltage V r is selected. The selected time constant T f will be output to the 34A4.

[0073] In the delay unit 34A7, the immediately preceding value τ2' of the second moment τ2 is selected at the time the second moment τ2 is input and output to the differentiator 34A3 and the summator 34A6. In the differentiator 34A3, a deviation τ1'-τ2' between the immediately preceding value τ1' of the first moment τ1 and the immediately preceding value τ2' of the second moment τ2 is generated and output to the divider 34A4. In the divider 34A4, the deviation τ1'-τ2' between the immediately preceding value τ1' of the first moment τ1 and the immediately preceding value τ2' of the second moment τ2 is divided by the time constant T. f In the multiplier 34A5, the output of the divisor 34A4 is multiplied by the discrete time period T. sIn the summing unit 34A6, the output of the multiplier 34A5 and the output of the delay unit 34A7 are added together and output to the selection unit 34A8.

[0074] In the block diagram of Fig. 13, corresponds to "z -1 y” in the first term on the right-hand side of the preceding formula (2) corresponds to the output of the delay unit 34A7. Additionally, “z” corresponds to -1 (uy)” in the second term on the right-hand side of the preceding formula (2) corresponds to the output of the differentiator 34A3. Furthermore, “(T f / T s )z -1 (uy)“ in the second term on the right-hand side of the preceding formula (2) of the output of the multiplier 34A5.

[0075] The selection unit 34A8 switches the output value depending on the magnitude ratio between the first moment τ1 and the immediately preceding value τ2' of the second moment τ2. Specifically, if the first moment τ1 is equal to or less than the immediately preceding value τ2' of the second moment τ2, the first moment τ1 is selected. Conversely, if the first moment τ1 is greater than the immediately preceding value τ2' of the second moment τ2, the summing unit 34A6 is selected. This configuration is used to avoid suppressing the rate of change of the second moment τ2 during operation when the first moment τ1 is decreasing. The effect is the same as, or equivalent to, that of the first embodiment, meaning the effect of the rate-of-change control unit 34 in the first embodiment.

[0076] Fig. Figure 14 shows a diagram that presents an example of the time constant table 34A2, which is in Fig. 13 is shown. On the left side of the Fig. Figure 14 is a table for a case where the torque command is a power-driving torque, represented as a graph. On the right side of the Fig. Figure 14 is a table in a case where the command moment is a regenerative moment, represented as a graph.

[0077] In the case where the first moment τ1 is a power driving torque, a fixing is carried out such that the smaller the received voltage V r The larger the time constant T f is, as shown in the diagram on the left side of the Fig. Figure 14 illustrates this. Specifically, in the case where the received voltage V r As the value decreases, a first fixed value T is determined. f1 received until the received voltage V r the first threshold V th1reached. When the received voltage V r below the first threshold V th1 As the value of the time constant T decreases f to until the received voltage V r the second threshold V th2 reached. The second threshold V th2 is smaller than the first threshold V th1 Then, when the received voltage V r the second threshold V th2 Once this value is reached, a second fixed value T is determined. f2 , which is a fixed value of the time constant at the second threshold V th2 is, then received.

[0078] In the case where the first moment τ1 is a regenerative moment, a fixing is carried out such that the greater the received voltage V r The larger the time constant T f is, as shown in the diagram on the right side of the Fig. Figure 14 is shown. Specifically, in the case where the received voltage V rAs the value increases, a third fixed value T is used. f3 received until the received voltage V r the third threshold V th3 reached. When the received voltage V r the third threshold V th3 If the value of the time constant T exceeds the value of the time constant T f increased until the received voltage V r the fourth threshold V th4 reached. The fourth threshold V th4 is greater than the third threshold V th3 Then, when the received voltage V r the fourth threshold V th4 Once reached, a fourth fixed value T is set. f4 , which is a fixed value of the time constant at the fourth threshold V th4 is, then received.

[0079] The first threshold V th1, the second threshold V th2 , the third threshold V th3 and the fourth threshold V th4 in the time constant table of the Fig. 14 can be set to the same values ​​as those in the change quantity limit table of the Fig. 9 or can be set independently.

[0080] As described above, according to the propulsion control device of the second embodiment, it is possible to achieve a function equivalent to that of the rate-of-change control unit 34 in the first embodiment by adding the rate-of-change control unit 34A to the torque command calculation unit 30. This makes it possible to achieve an effect similar to that of the first embodiment.

[0081] Third embodiment.

[0082] In a third embodiment, a further example configuration of the moment command calculation unit 30 is described. Fig. Figure 15 shows a block diagram illustrating a configuration of a torque command calculation unit 30A in the third embodiment. The torque command calculation unit 30A further includes a limiter processing unit 36, which is located on a downstream side of the rate-of-change control unit 34 in the configuration of the torque command calculation unit 30, which is shown in Fig. Figure 7 is shown. Other configurations are the same as or equivalent to those shown in the Fig. Figure 7. The rate-of-change control unit 34A, described in the second embodiment, can be used instead of the rate-of-change control unit 34. Configurations of components other than the torque instruction calculation unit 30A are the same as or equivalent to those of the first embodiment, and their descriptions are omitted here.

[0083] As described in the first and second embodiments, the transient increase and decrease of the received voltage V can be r This can be suppressed by suppressing the rate of change of the first moment τ1. However, the voltage drop due to the impedance element Z can be suppressed. L in a steady state, that is, the difference between the power supply voltage V f and the received voltage V r not be completely eliminated. Accordingly, in a preferred embodiment, a control to reduce the power driving torque is implemented when the received voltage V r decreases and a control to reduce the regenerative torque is executed when the received voltage V r increases. To implement these types of control, the limiter processing unit 36 ​​is provided in the third embodiment.

[0084] In Fig. 15 become the second moment τ2, which is the output of the rate of change control unit 34, the received voltage V r , the speed information ω m The speed information ω was entered into the limiter processing unit 36. m This is information representing the rotational speed of the electric motor 120. Inverter frequency or speed information for the electric vehicle can be input to the limiter processing unit 36 ​​instead of the rotational speed of the electric motor 120. The limiter processing unit 36 ​​generates and outputs, in addition to a third torque τ3 based on the second torque τ2, the applied voltage V r and the speed information ω m In the configuration of Fig. In the third embodiment, the third torque τ3 is generated by the limiter processing unit 36 ​​and becomes a torque command τ*, which is generated by the torque command calculation unit 30A. This means that in the third embodiment, a current command value in a vector control is calculated based on the third torque τ3.

[0085] Fig. Figure 16 shows a diagram representing an example configuration of the limiter processing unit 36, which is described in Fig. 15 is shown. As in the Fig. As shown in Figure 16, the limiter processing unit 36 ​​includes a power limiter table 36a, a divider 36b, a selection unit 36c, a stabilization filter 36d, comparators 36e and 36g, filter control units 36f and 36i and a delay unit 36h.

[0086] The power limiter table 36a is configured to receive, as an input, the received voltage V rand configures a power limit value P for this purpose L to be output. The power limit value P L The output is sent to divisor 36b. An upper moment limit value τ is stored in divisor 36b. L calculated. The upper moment limit value τ L is obtained by dividing the power limit value P L through the speed information ω m In selection unit 36c, a smaller value is determined by the second moment τ2 and the upper moment limit value τ. LThe second moment τ2 is selected and output to the stabilization filter 36d. In the comparator 36e, the second moment τ2 is compared with the output of the divider 36b, and the result of the comparison is output to the filter control unit 36f. In the delay unit 36h, an immediately preceding value τ3' of the third moment τ3 is selected at the time the third moment τ3 is input and output to the comparator 36g. In the comparator 36g, the second moment τ2 is compared with the immediately preceding value τ3' of the third moment τ3, and the result of the comparison is output to the filter control unit 36i. The operation of the stabilization filter 36d and the filter control units 36f and 36i is described later.

[0087] Fig. Figure 17 shows a diagram illustrating an example of the power limiter table 36a, which is found in Fig. 16 is shown. On the left side of the Fig. Figure 17 is a table representing a case where a command torque is a power driving torque, as a graph. On the right side of the Fig. Figure 17 is a table in a case where the command moment is a regenerative moment, represented as a graph.

[0088] In the case where the first moment τ1 is a power driving torque, a fixing is carried out such that the smaller the received voltage V r The smaller the power limit value P L is as shown in the diagram on the left side of the Fig. 17. Specifically, in the case where the received voltage V r as the power limit decreases, a first power limit value P is set. L1 received until the received voltage V r a fifth threshold V th5 reached. When the received voltage V r below the fifth threshold V th5 The power limit value P falls Lreduced until the received voltage V r a sixth threshold V th6 reached. The sixth threshold V th6 is smaller than the fifth threshold V th5 Then, when the received voltage V r the sixth threshold V th6 Once this value is reached, a second power limit value P is applied. L2 , which is a fixed value of the power limitation value P L at the sixth threshold V th6 is, then received.

[0089] In the case where the first moment τ1 is a regenerative moment, a fixing is carried out such that, the greater the received voltage V r The smaller the power limit value P L is, as shown in the diagram on the right side of the Fig. 17 shown. Specifically in the case where the received voltage V r As the power limit increases, a third limit value P is applied. L3received until the received voltage V r a seventh threshold V th7 reached. When the received voltage V r the seventh threshold V th7 if the power limit value P is exceeded L reduced until the received voltage V r an eighth threshold V th8 reached. The eighth threshold V th8 is less than the seventh threshold V th7 Then, when the received voltage V r the eighth threshold V th8 Once this value is reached, a fourth power limit value P is applied. L4 , which is a fixed value of the power limitation value P L at the eighth threshold V th8 is, received.

[0090] The fifth threshold V th5 , the sixth threshold V th6 , the seventh threshold V th7 and the eighth threshold V th8 in the performance limiter table of the Fig. 17 can be set to the same values ​​as those specified in the change quantity limit table in Fig. 9 or the time constant table in Fig. 14 are displayed, or they can be set independently.

[0091] In the description of the Fig. 16 described that the selection unit 36c selects the smaller of the second moment τ2 and the upper moment limit value τ L . selects and outputs the value to the stabilization filter 36d. However, if the upper moment limit value τ L is smaller than the second moment τ2, that is, if the power limitation is allowed, the following problem occurs. (1) The third moment τ3 changes depending on the received voltage V r . (2) An actual torque of this electric motor 120 is controlled so that it coincides with the third torque τ3. (3) When the torque or power of the electric motor 120 changes, a voltage drop due to the impedance element Z changes. L and the power supply voltage V f It also fluctuates transiently. (4) The received voltage V r changes and the third moment τ3 changes.

[0092] There is a possibility that the received voltage oscillates due to the repetition of processes (1) to (4). To avoid this problem, the stabilization filter 36d is used in the third embodiment. It is assumed that the frequency response characteristic of the stabilization filter 36d exhibits at least low-pass characteristics. This characteristic achieves the effect of stabilizing the received voltage V. r by damping the oscillation of the received voltage V r , which is caused by an interaction under the power supply 110, the impedance element Z Land is effected by the propulsion control device 1.

[0093] However, assuming that the stabilization filter 36d is primarily configured to exhibit low-pass characteristics, even when power limiting is not enabled, that is, when the second moment τ2 is equal to or less than the moment limit value τ L If the moment τ3 is delayed with respect to the second moment τ2, the stabilization filter 36d is interposed and configured as follows.

[0094] If τ2>τ L The following condition is met: the stabilization filter 36d is switched on.

[0095] If τ2≤τ2' is satisfied: the stabilization filter 36d is switched off.

[0096] The function described above can be achieved by the stabilization filter 36d and the filter control units 36f and 36i, as shown in Fig. As shown in section 16, this can be implemented. What is meant by "the filter is switched off" is that "the input value is output as it is".

[0097] Fig. Figure 18 shows a diagram to illustrate a state in which the power limiter is switched on and the stabilization filter is switched between on and off. Fig. Figure 18 represents a thick dashed line for the first moment τ1, a thick solid line represents the moment τ2, and a solid line represents the moment τ3. A section common to the first moment τ1, the second moment τ2, and the third moment τ3 is also shown as a solid line. A dashed line represents the upper moment limit τ L .

[0098] The moment limit value τ begins at time t0. L to decrease. The moment limit value τ Lbegins to decrease because the received voltage V r decreases and the fifth threshold of V th5 in the performance limiter table 36a.

[0099] Time t1 is the time when the received voltage V r has decreased further and reached the first threshold V th1 in the change quantity limitation table 34b or the time constant table 34A2. Accordingly, the second moment τ2, which has a different value than the first moment τ1, is generated after time t1.

[0100] At time t2, the second moment τ2 occurs with the moment limiting value τ. L together and after time t2, the second moment τ2 exceeds the moment limit value τ LAccordingly, the power limitation control is started and at the same time the stabilization filter 36d is switched on. Since the stabilization filter 36d is switched on, the oscillation of the torque limit value τ L , which are caused by the fluctuation of the received voltage V r is caused, as in Fig. 18 shown; suppressed. This means that by switching on the stabilization filter 36d, the fluctuation of the received voltage V is suppressed. r is suppressed.

[0101] At time t3, the second moment τ2 occurs with the moment limiting value τ. L together and after time τ3 the second moment τ2 falls below the moment limit value τ LAccordingly, selection unit 36c selects one with a smaller value from among the inputs. Therefore, the second moment τ2 is output by selection unit 36c. Almost simultaneously, the second moment τ2 falls below the third moment τ3; therefore, the stabilization filter 36d is switched off. Consequently, after time t3, the second moment τ2 and the third moment τ3 coincide, as shown in the figure.

[0102] As described above, according to the propulsion control device of the third embodiment, the torque command calculation unit 30A includes the limiter processing unit 36. Therefore, together with the effects of the first and second embodiments, an effect of stabilizing the received voltage V can be achieved. r can be obtained. Fourth embodiment.

[0103] In a fourth embodiment, a further example configuration of the moment command calculation unit 30 is described. Fig. Figure 19 shows a block diagram illustrating a configuration of a torque command calculation unit 30B in the fourth embodiment. The torque command calculation unit 30B further includes a sliding control unit 38, which is provided on the downstream side of the limiter processing unit 36 ​​in the configuration of the torque command calculation unit 30A, which is shown in Fig. Figure 15 is shown. Other configurations are the same as or equivalent to those shown in the Fig. Figure 15 illustrates this. The rate-of-change control unit 34A, described in the second embodiment, can be used instead of the rate-of-change control unit 34. Configurations of components other than the torque instruction calculation unit 30B are the same as or equivalent to those of the first embodiment, and their description is omitted here.

[0104] The sliding control unit 38 has the function of detecting a slip state of the wheels of an electric vehicle or a grip state of the wheels. The sliding control unit 38 further has the function of reducing the torque of the electric motor 120 when wheel slip of the electric vehicle is detected in order to restore grip to the wheels, and restoring the torque of the electric motor 120 after the wheels regain grip. Various configurations of the sliding control unit 38 have been proposed and are publicly known; therefore, a detailed description is omitted here.

[0105] As shown in the figure, the glide control unit 38 generates and outputs a fourth moment τ4, which is obtained by controlling the increase or decrease of a moment on the third moment τ3 for the purpose of glide control. In the configuration of the Fig. In the fourth embodiment, the fourth moment τ4, generated by the sliding control unit 38, becomes a moment command τ*, generated by the moment command calculation unit 30B. This means that, in the fourth embodiment, a current command value is calculated in the vector control based on the fourth moment τ4. If the moment command calculation unit 30B does not have the limiter processing unit 36, the sliding control unit 38 can receive the second moment τ2 as an input.

[0106] With the configuration of Fig. 19, the calculation result of the sliding control unit 38 is immediately reflected in the actual torque of the electric motor 120. This allows a conventional sliding control algorithm to function adequately. Assume that the sliding control unit 38 is provided upstream of the rate-of-change control unit 34. With this configuration, the rate of change is also suppressed by the rate-of-change control unit 34 with respect to the calculation result of the sliding control unit 38. It is further assumed that the sliding control unit 38 is provided upstream of the limiter processing unit 36. With this configuration, the torque limit value τ L . output for a period of time during which the power limit is switched on; therefore, the calculation result of the sliding control unit 38 is ignored.

[0107] As described above, according to the propulsion control device of the fourth embodiment, the torque command calculation unit 30B includes the sliding control unit 38. Therefore, it is possible to achieve an effect that allows its conventional sliding control algorithm to function sufficiently, as does the effect of the first embodiment, the second embodiment, and the third embodiment.

[0108] Ultimately, a hardware configuration for realizing the function of the torque instruction calculation units 30, 30A and 30B in the first to fourth embodiments is defined with respect to the Fig. 20 and Fig. 21 described.

[0109] In a case of implementing the functions of the moment instruction calculation units 30, 30A and 30B, as described above, a configuration can be used that has a central processing unit (CPU) 200 that performs calculations, a memory 202 that stores a program to be read by the CPU 200, and an interface 204 that inputs / outputs signals, as shown in Fig. Figure 15 illustrates this. The CPU 200 can be a computing unit such as a microprocessor, a microcomputer, a processor, or a digital signal processor (DSP). The memory 202 corresponds to a non-volatile or volatile semiconductor memory such as random access memory (RAM), read-only memory (ROM), flash memory, erasable programmable ROM (EPROM), or electrical EPROM (EEPROM).

[0110] Specifically, memory 202 stores programs for executing the functions of the torque instruction calculation units 30, 30A and 30B. The CPU 200 performs various calculation operations, described in the first to fourth embodiments, by exchanging necessary information via interface 204.

[0111] The CPU 200 and the memory 202, which are in the Fig. The 20 shown can be processed by a processing circuit 203, as shown in the Fig. 21 shown, can be replaced. The processing circuit 203 corresponds, for example, in the individual circuit, in the compound circuit, to a programmed processor, a parallel programmed processor, an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or combinations thereof.

[0112] The configurations described in the preceding embodiments are merely examples of one aspect of the present invention and can be combined with other known technologies, and parts thereof can be omitted or modified without departing from the scope of protection of the present invention. Reference symbol list

[0113] 1, 1A, 1B, 1C Propulsion control device; 2 Power converter device; 3 Control device; 20 Rectifier; 20B, 20C Diode rectifier; 22 Inverter; 30, 30A, 30B Torque command calculation unit; 32 Target value calculation unit; 34a, 34A3 Differentiator; 34b Change quantity limit table; 34c, 34A8, 36c Selection unit; 34d, 34A1, 34A7, 36h Delay unit; 34e, 34A6 Summer; 34, 34A Rate of change control unit; 34A2 Time constant table; 34A4, 36b Divider; 34A5 Multiplier; 36 Limiter processing unit; 36a Power limiter table; 36d Stabilization filter; 36f, 36i Filter control unit; 36e, 36g Comparator; 38 Sliding control unit; 100, 100A, 100B, 100C Electric vehicle drive system; 106 Power supply equipment; 108 AC overhead line; 110, 110A, 110B, 110C Power supply; 111 Diesel engine; 112 Generator; 120 Electric motor; 200 CPU; 202 Memory; 203 Processing circuit; 204 Interface.

Claims

[1] Propulsion control device (1) which controls a power converter device (2) which supplies power to an electric motor (120) which drives an electric vehicle, wherein the propulsion control device (1) comprises a torque command calculation unit (30) for calculating a torque to be generated by the electric motor (120), wherein the moment command calculation unit (30) has: a target value calculation unit (32) for calculating a first moment (τ1) based on an operating instruction; and a rate-of-change control unit (34) for calculating and outputting a second moment (τ2), wherein the second moment (τ2) is a moment obtained by suppressing a rate of change of the first moment (τ1) with reference to a received voltage (V) r ) is obtained, whereby the received voltage (V r) is a voltage at which the power converter device (2) receives a power input, where, if the first moment (τ1) is a power path moment, the rate of change control unit (34) performs a control such that, the smaller the received voltage (V) r ) is, the smaller the rate of change of the second moment ((τ2) is. [2] Propulsion control device (1) which controls a power converter device (2) which supplies power to an electric motor (120) which drives an electric vehicle, wherein the propulsion control device (1) comprises a torque command calculation unit (30) for calculating a torque to be generated by the electric motor (120), wherein the moment command calculation unit (30) has: a target value calculation unit (32) for calculating a first moment (τ1) based on an operating instruction; and a rate-of-change control unit (34) for calculating and outputting a second moment (τ2), wherein the second moment (τ2) is a moment obtained by suppressing a rate of change of the first moment (τ1) with reference to a received voltage (V) r ) is obtained, whereby the received voltage (V r ) is a voltage at which the power converter device (2) receives a power input, where, if the first moment (τ1) is a regenerative moment, the rate of change control unit (34) performs a control such that the larger the received voltage (V) r ) is, the greater the rate of change of the second moment (τ2) is, where, if the first moment (τ1) is equal to or less than the second moment (τ2), the rate of change control unit (34) does not control the rate of change of the second moment (τ2). [3] Propulsion control device (1) which controls a power converter device (2) which supplies power to an electric motor (120) which drives an electric vehicle, wherein the propulsion control device (1) has a torque command calculation unit (30) for calculating a torque to be generated by the electric motor (120), wherein the moment command calculation unit (30) has: a target value calculation unit (32) for calculating a first moment (τ1) based on an operating instruction; and a rate-of-change control unit (34) for calculating and outputting a second moment (τ2), wherein the second moment (τ2) is a moment obtained by suppressing a rate of change of the first moment (τ1) with reference to a received voltage (V) r ) is obtained, whereby the received voltage (V r) is a voltage at which the power converter device (2) receives a power input, wherein the rate of change control unit (34) sets a rate of change limit value (Δτ) of a second moment (τ2) per calculation cycle based on the received voltage (V r ) calculates a deviation between the first moment (τ1) and the second moment (τ2') in a previous calculation cycle, and adds the smaller of the change quantity limit value (Δτ) and the deviation to the second moment (τ2') in the one previous calculation cycle to update the second moment (τ2). [4] Propulsion control device (1) controlling a power converter device (2) which supplies power to an electric motor (120) which drives an electric vehicle, wherein the propulsion control device (1) comprises a torque command calculation unit (30) for calculating a torque to be generated by the electric motor (120), wherein the moment command calculation unit (30) has: a target value calculation unit (32) for calculating a first moment (τ1) based on an operating instruction; and a rate-of-change control unit (34) for calculating and outputting a second moment (τ2), wherein the second moment (τ2) is a moment obtained by suppressing a rate of change of the first moment (τ1) with reference to a received voltage (V) r ) is obtained, whereby the received voltage (V r ) is a voltage at which the power converter device (2) receives a power input, wherein the rate of change control unit (34) sets a limit value of a change quantity of a second moment (τ2) per unit time based on the received voltage (V) r) calculated, and controls the second moment (τ2) such that the rate of change of the second moment (τ2) per unit of time does not exceed the limiting value. [5] Propulsion control device (1) according to one of claims 1 to 2, wherein the rate of change control unit (34A) performs a filtering operation on the first moment (τ1) in order to calculate the second moment (τ2), and a constant for determining a frequency response of the filtering process based on the received voltage (V) r ) is calculated. [6] Propulsion control device (1) according to any one of claims 1 to 5, wherein the propulsion control device (1) calculates a current command value in vector control on a basis of the second moment (τ2). [7] Propulsion control device (1) controlling a power converter device (2) which supplies power to an electric motor (120) which drives an electric vehicle, wherein the propulsion control device (1) has a torque command calculation unit (30) for calculating a torque to be generated by the electric motor (120), wherein the moment command calculation unit (30) has: a target value calculation unit (32) for calculating a first moment (τ1) based on an operating instruction; and a rate-of-change control unit (34) for calculating and outputting a second moment (τ2), wherein the second moment (τ2) is a moment obtained by suppressing a rate of change of the first moment (τ1) with reference to a received voltage (V) r ) is obtained, whereby the received voltage (V r) is a voltage at which the power converter device (2) receives a power input, where the torque instruction calculation unit (30A) has a limiter processing unit (36), the limiter processing unit (36) has a stabilization filter (36d) which has at least a low-pass characteristic in a frequency response, and the limiter processing unit (36) generates and outputs a third moment (τ3) which is calculated by calculating a moment limit value (τ L ) based on a speed of the electric vehicle or a rotational speed of the electric motor (120) and the received voltage (V r ) was obtained, and performing a process through the stabilization filter (36d) on the smaller of the second moment (τ2) and the moment limit value (τ L ). [8] Propulsion control device (1) according to claim 7, wherein the propulsion control device (1) calculates a current command value in vector control on a basis of the third moment (τ3). [9] Propulsion control device (1) according to any one of claims 1 to 5, wherein the moment command calculation unit (30B) has a sliding control unit (38), and the sliding control unit (38) generates and outputs a fourth moment (τ4) which is obtained by performing a control of increasing or reducing a moment on the second moment (τ2), depending on a slip state of a wheel of the electric vehicle or a grip state of the wheel. [10] Propulsion control device (1) according to claim 7, wherein the moment command calculation unit (30B) has a sliding control unit (38), and the sliding control unit (38) generates and outputs a fourth moment (τ4) which is obtained by performing a control of increasing or reducing a moment to the third moment (τ3), depending on a slip state of a wheel of the electric vehicle or a grip state of the wheel. [11] Propulsion control device (1) according to claim 9 or 10, wherein the propulsion control device (1) calculates a current command value in vector control on a basis of the fourth moment (τ4).

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