Vehicle drive control device and method thereof

Abstract

A vehicular driving control device comprises: an electric power conversion circuit that is connected to a DC power source and that supplies electric power of the DC power source to an electric motor in accordance with a voltage command; a filter circuit configured to be interposed between the DC power source and the DC side of the electric power conversion circuit and to have a reactor and a capacitor; a variation detection unit for detecting a varying component of the electrical quantity regarding the filter circuit; a torque control unit for generating the voltage command applied to the electric motor in accordance with a torque command or a current command; and a damping control unit for operating the electric power conversion circuit so as to suppress the varying component. The damping control unit operates the electric power conversion circuit in accordance with a damping operation amount based on a first operation amount calculated in accordance with the torque command or the current command and the varying component and a second operation amount calculated in accordance with the varying component and rotation rate information relating to the electric motor. Accordingly, it is possible to provide a vehicular driving control device that performs damping control at a fixed attenuation, regardless of the voltage of DC wires or operating point of the electric motor, with respect to oscillation of capacitor voltage.

Description

[Technical field]

[0001] The present invention relates to a vehicle drive control device and a method thereof. [Background technology]

[0002] The technology of controlling the output torque of electric motors is widely used in industry. In electric railways, a configuration in which an inverter device using a DC overhead line as a power source controls the torque of an electric motor is also widely used.

[0003] In DC railway vehicles (hereinafter also referred to as "vehicles"), a filter circuit consisting of a reactor and a capacitor is generally provided to prevent the harmful effect of harmonic currents flowing out from the DC side of the inverter device. However, it is known that the combination of this filter circuit and the inverter device forms an unstable resonance system, which causes the capacitor voltage to oscillate, making the control of the motor unstable.

[0004] Damping control is a control that suppresses this oscillation phenomenon and is essential for the stable operation of DC electric railcars. In addition, properly attenuating the oscillation of the capacitor voltage through damping control is important for reducing induced interference caused by return current.

[0005] Patent Document 1 discloses a method of calculating the rate of fluctuation of the capacitor voltage, manipulating the current command or torque command of the vector control unit using a damping control amount corresponding to that rate of fluctuation, and controlling the inverter current in a direction that suppresses the fluctuation of the capacitor voltage. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] International Publication No. 2008 / 026249 Summary of the Invention [Problem to be solved by the invention]

[0007] However, the damping control of Patent Document 1 has a problem in that when the torque command is large, the damping of the fluctuation of the capacitor voltage becomes strong, and when the torque command is small, the damping becomes weak. The present invention has been made in consideration of the above problem, and an object of the present invention is to provide a vehicle drive control device capable of damping control that provides a constant damping to the vibration of the capacitor voltage regardless of the voltage of the DC overhead line or the operating point of the electric motor. [Means for solving the problem]

[0008] The present invention, which solves the above-mentioned problems, is a vehicle drive control device that includes a power conversion circuit connected to a DC power source and supplying power from the DC power source to an electric motor in response to a voltage command, a filter circuit interposed between the DC side of the power conversion circuit and the DC power source and configured with a reactor and a capacitor, a fluctuation detection unit that detects a fluctuation component of an electrical quantity related to the filter circuit, a torque control unit that generates a voltage command to be applied to the electric motor in response to a torque command or a current command, and a damping control unit that operates the power conversion circuit to suppress the fluctuation component, wherein the damping control unit operates the power conversion circuit in response to a damping operation amount that is based on a first operation amount calculated in response to the torque command or current command and the fluctuation component, and a second operation amount calculated in response to rotational speed information of the electric motor and the fluctuation component. Effect of the Invention

[0009] According to the present invention, it is possible to provide a vehicle drive control device capable of performing damping control to provide a constant damping to the oscillations of the capacitor voltage, regardless of the voltage of the DC overhead line or the operating point of the motor. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a functional block diagram showing an outline of a vehicle drive control device (hereinafter, referred to as "the device") 10A according to a first embodiment of the present invention. [Diagram 2]2 is a detailed control circuit diagram of a damping control unit 11 in FIG. 1. FIG. [Diagram 3] FIG. 10 is a functional block diagram showing a vehicle drive control device (also referred to as "the device") 10B according to a second embodiment of the present invention. [Figure 4] 4 is a detailed control circuit diagram of the damping control unit 111 of FIG. 3. [Diagram 5] FIG. 11 is a functional block diagram showing an outline of a vehicle drive control device (also referred to as "the device") 10C according to a third embodiment of the present invention. [Figure 6] 6 is a detailed control circuit diagram of the damping control section 211 of FIG. 5. [Figure 7] FIG. 11 is a schematic circuit diagram of a fluctuation detection unit 330 according to a fourth embodiment of the present invention. [Figure 8] FIG. 11 is a schematic circuit diagram of a fluctuation detection unit 430 according to a fifth embodiment of the present invention. [Figure 9] FIG. 6 is a diagram showing only parts of a vehicle drive control device (also referred to as "the device") 10F according to a sixth embodiment of the present invention that differ from the first embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS EXAMPLES

[0011] 1 is a functional block diagram showing an outline of a device 10A according to a first embodiment. The device 10A supplies power taken in from a DC overhead line 1 to an induction motor 5. The device 10A mainly includes an inverter 4, a filter circuit consisting of a reactor 2 and a capacitor 3, a damping control unit 11, a vector control unit 20, and a fluctuation detection unit 30.

[0012] In addition to the device 10A of the first embodiment, the devices 10B to 10F of the second to sixth embodiments will each have their own characteristics, which will be described later, but will be collectively referred to as the device 10 unless there is a need to distinguish between them. The reactor 2 is connected in series between the DC overhead line 1 and the DC side of the inverter 4, and the capacitor 3 is connected in parallel to the DC side of the inverter 4, to prevent harmonic currents generated on the DC side of the inverter 4 from flowing out to the DC overhead line 1.

[0013] In the device 10A of the first embodiment, a case where an induction motor 5 is combined with an inverter 4 will be described, but a synchronous motor may be used after appropriately modifying the configuration of the vector control unit. Also, torque control may be performed by combining a DC motor with a chopper circuit. Furthermore, if the torque and rotation speed in the following description are replaced with thrust and speed, the present invention is also useful when a linear motor is used.

[0014] The inverter 4 is a circuit that converts a DC voltage into a three-phase AC voltage of any frequency and any amplitude, and is capable of both power running operation, in which power is supplied from the DC side to the induction motor 5 on the AC side, and regenerative operation, in which power is supplied from the induction motor 5 on the AC side to the DC side.

[0015] The fluctuation detection unit 30 mainly detects the capacitor voltage E cf The fluctuation component of e cf The characteristic of the bandpass filter 31 may be provided with phase lead compensation in consideration of the operation delay of the vector control unit 20.

[0016] Also, instead of a band-pass filter, a different filter such as a high-pass filter may be used, and when there is a known disturbance at a specific frequency, the filter may have the characteristic of selectively blocking the component of that frequency.

[0017] The damping control unit 11 controls the voltage E cf The damping control amount τ to suppress the vibration of D * The adder 12 generates a torque command τ0 which the device 10 receives from a higher-level control system (not shown) in order to generate a driving force required to accelerate or decelerate the vehicle. * The damping control unit outputs the damping operation amount τ D * The torque command τ1 is given to the vector control unit 20. * Calculate.

[0018] The vector control unit 20 determines whether the torque τ output by the induction motor 5 is equal to the torque command τ1 * This vector control unit 20 performs control calculations in a rotating coordinate system consisting of a d-axis whose direction coincides with the rotor flux linkage of the induction motor 5 and a q-axis perpendicular to the d-axis, as is well known as vector control.

[0019] The vector control unit 20 receives a d-axis magnetic flux command φ * 2d and torque command τ * 1 and the three-phase current I flowing through the induction motor 5 U ,I V ,I W and the rotation speed ω of the induction motor 5 r and the three-phase voltage command V * U ,V * V ,V * W The vector control unit 20 in FIG. 1 may be considered to include a torque control unit (not shown).

[0020] This torque control section is configured to control the torque command τ0 * , τ1 * , or current command I * 1d ,I ** 1q In response to this, the voltage command V applied to the motor 5 is * U ,V * V ,V * W The torque control unit generates the torque command τ0 when the output torque τ of the motor 5 or the current flowing through the motor 5 is greater than the torque command τ0. * , τ1 * or current command I * 1d ,I ** 1q The voltage command V * U ,V * V ,V *W Any vector control system that generates the above formula is sufficient.

[0021] The vector control unit 20 is made up of a current command calculation unit 21, a current control unit 22, a slip frequency calculation unit 23, a PWM waveform generation unit 25, a phase calculation unit 24, and a coordinate conversion unit 26.

[0022] The vector control unit 20 of the first embodiment controls the rotation speed ω r The vector control unit 20 calculates the rotation speed ω of the induction motor 5 based on various information within the vector control unit 20, such as the three-phase current flowing through the induction motor 5, the terminal voltage of the induction motor 5, and the like. r Alternatively, the control may be performed using an estimated value.

[0023] The configuration of the vector control unit 20 will be described below. A current command calculation unit 21 receives a d-axis magnetic flux command φ * 2d , torque command τ * 1, the d-axis current command I * 1d and q-axis current command I * 1q where s is the Laplace operator, L2 is the rotor self-inductance of the induction motor 5, R2 is the rotor resistance of the induction motor 5, M is the mutual inductance of the induction motor 5, and N p is the number of pole pairs of the induction motor 5.

[0024]

number

[0025] The current control unit 22 controls the d-axis current I 1d and the q-axis current I 1q are the d-axis current command I * 1d and the q-axis current command I * 1qIn order to match this, the d-axis voltage command V d * and the q-axis voltage command V q * Generate.

[0026] where L1 is the stator self-inductance of the induction motor 5, R1 is the stator resistance of the induction motor 5, and ω inv is the angular velocity of the three-phase AC voltage output by the inverter 4, ω acr is the response angular frequency of the current control unit 22. Also, σ is a leakage coefficient calculated from the circuit constants of the induction motor 56 by the following equation (3).

[0027]

number

[0028] In order to match the direction of the d-axis with the direction of the rotor interlinkage magnetic flux of the induction motor 5, the slip frequency calculation unit 23 calculates the rotational angular velocity of the rotor interlinkage magnetic flux of the induction motor 5 and the angular velocity ω inv The slip frequency calculation unit 23 estimates the slip frequency, which is the difference between the d-axis magnetic flux command φ * 2d and the q-axis current command I * 1q From the circuit constants of the induction motor 5, the slip frequency estimate ω * s Calculate.

[0029]

number

[0030] The phase calculation unit 24 calculates the phase angle θ of the three-phase AC voltage output from the inverter 4. The phase calculation unit 24 calculates the rotation speed ω r and the slip frequency estimate ω * s The phase angle θ of the three-phase AC voltage is calculated according to the following equation (7).

[0031]

number

[0032] The PWM waveform generating unit 25 calculates the phase angle θ of the three-phase AC voltage output by the inverter 4 and the d-axis voltage command V d * and q-axis voltage command V q * Depending on the three-phase switching signal V * U ,V * V ,V * W The coordinate transformation unit 26 outputs the three-phase current I U ,I V ,I W Using the following equation (8), the d-axis current I 1d and q-axis current I 1q Such an operation of the vector control unit 20 is a method widely known as indirect vector control.

[0033]

number

[0034] 2 is a detailed control circuit diagram of the damping control unit 11 in FIG. 1. The damping control unit 11 mainly controls the capacitor voltage E cf DC component of E cf The control circuit 10 includes a low pass filter (LPF) 50 that extracts an input signal, an adder 51, a first manipulated variable calculation unit 60, and a second manipulated variable calculation unit 70. The first manipulated variable calculation unit 60 includes a divider 61 and a multiplier 62.

[0035] The first operation amount calculation unit 60 calculates the torque command τ * Capacitor voltage E to 0 cf The fluctuation component of e cf Multiplying by, the capacitor voltage Ecf DC component (with underline) E cf This value is the first manipulated variable τ * D1 The second operation amount calculation unit 70 calculates the capacitor voltage E cf DC component (with underline) E cf and the capacitor voltage E cf The fluctuation component of e cf The proportional constant 71 is multiplied by the rotation speed ωr of the induction motor 5 to calculate a value. This value is the second operation amount τ * D2 It is.

[0036] First manipulated variable τ * D1 and the second control variable τ * D2 The damping operation amount τ * D The proportionality constant 71 used for multiplication in the second manipulated variable calculation unit 70 may be a constant value at all times, or may be a variable value that takes into account the operational delays of the inverter 4 and the vector control unit 20.

[0037] The second operation amount calculation unit 70 may switch the value of the proportionality constant 71 depending on whether the inverter 4 is in a powering operation or a regenerative operation. * D1 and the second control input τ * D2 They may be used in a state where at least one of them is disabled, or in a state where both are enabled.

[0038] When the DC voltage is known, the device 10A converts the voltage into the capacitor voltage E cf DC component (with underline) E cf A specific example of such a case is when the device 10A receives DC power from a power conversion device that performs constant voltage control, instead of the DC overhead line 1.

[0039] Before describing the effects of the first embodiment, the capacitor voltage E cfThis section describes the principle of occurrence of the vibration phenomenon and the theoretical basis of vibration suppression by the configuration of Example 1. The resonant frequency of a filter circuit consisting of a reactor 2 and a capacitor 3 that is the target of damping control is usually 10 Hz to 20 Hz, and therefore the period is about 50 to 100 ms.

[0040] In such a time period of the resonance period of the filter circuit, the vehicle speed does not change suddenly. Also, in the same time period, the torque command τ * The rotation speed ω of the induction motor 5 is not 0, and does not change suddenly. r and torque command τ * 0 and can be treated as constants.

[0041] Here, the torque command τ * 0 and torque command τ * 1 is equal to the torque command τ * If it is equal to 1, the number of pole pairs of the induction motor 5 is N. p Then, the mechanical output ω of the induction motor 5 is r τ / N p If we ignore the losses inside the device 10A and the induction motor 5, the power P inv is the mechanical output ω of the induction motor 5 r τ / N p and therefore is also constant, and the following equation (9) holds:

[0042]

number

[0043] The current that inverter 4 draws from the DC side is I inv Then, the following equation (10) holds.

[0044]

number

[0045] Based on the above equations (9) and (10), the capacitor voltage E cf The fluctuation component of e cf For I inv The fluctuation component i inv The ratio is calculated as the following formula (11). Here, the DC component of the current drawn by the inverter 4 from the DC side is (underlined) I inv It was decided.

[0046]

number

[0047] Here, the fluctuation component e of the voltage of DC overhead line 1 is s From the above, the capacitor voltage E cf The fluctuation component of e cf When the closed loop transfer function is calculated, it becomes a second-order transfer function as shown in the following equation (12).

[0048]

number

[0049] This is the resonant angular frequency ω n and rewriting it using the damping coefficient ζ gives the following equation (13).

[0050]

number

[0051] By comparing the first-order coefficients of s in the denominators of the above equations (12) and (13), we obtain the following.

[0052]

number

[0053] It is generally known that the vibration phenomenon of the secondary system is attenuated when the damping coefficient ζ is positive, continues when it is 0, and expands when it is negative. Therefore, when the induction motor 5 is in power running operation (with an upper line), inv When becomes positive, the damping coefficient ζ becomes negative, and the capacitor voltage E cf The vibration increases over time, leading to control instability.

[0054] To prevent this from happening, inv / e cf In other words, the capacitor voltage E cf The fluctuation component of e cf According to the torque command τ * 1, and the mechanical output ω of the induction motor 5 r τ / N p The inverter 4 draws power P from the DC side. inv To solve this problem, a damping control can be performed to vary the

[0055] Based on the above, the capacitor voltage E cf The damping coefficient ζ of the vibration of * In order to make the vibration equal to the vibration of the vehicle, the type of damping control required is derived, and the theoretical basis for vibration suppression according to the first embodiment is shown.

[0056] The fluctuation amount of the output torque τ of the induction motor 5 due to the damping control is τ D Then, the capacitor voltage E cf The fluctuation component of e cf Let the proportional constant be K D Then, the following equation (15) holds.

[0057]

number

[0058] Ignoring losses inside the device 10 and the induction motor 5, the power P drawn by the inverter 4 from the DC side is inv The component p that varies due to damping control invDUsing this, E cf The fluctuation component of e cf I inv The fluctuation component i inv The ratio is calculated as shown in the following formula (17).

[0059]

number

[0060] Using the above equation (17), the fluctuation component e of the voltage of DC overhead line 1 s From the above, the capacitor voltage E cf The fluctuation component of e cf When the closed loop transfer function is calculated, it becomes a second-order transfer function as shown in the following equation (18).

[0061]

number

[0062] The damping coefficient ζ of this second-order system is the desired positive value ζ * When this equation is true, the following equation (19) holds.

[0063]

number

[0064] proportionality constant K D By rearranging, we obtain the following equation (20).

[0065]

number

[0066] If we ignore losses inside the device 10 and the induction motor 5, the power P drawn by the inverter 4 from the DC side is inv and the mechanical output ω of the induction motor 5 r τ / N p The DC components of and are equal. In other words, the following equation (21) holds.

[0067]

number

[0068] Using the above equation (21), the proportionality constant K D This is calculated as the following equation (22).

[0069]

number

[0070] Using the above equations (15) and (22), the fluctuation amount τ of the output torque τ of the induction motor 5 due to damping control is calculated. D The amount of fluctuation in the following equation (23) is τ D By varying the output torque τ of the induction motor 5 in accordance with the above, the object of the present device 10A can be achieved.

[0071]

number

[0072] The first term in the above equation (23) is the torque command τ * 0 and the capacitor voltage E cf The fluctuation component of e cf The second term of the above equation (23) is proportional to the rotation speed ω r These are inversely proportional to the first operation amount τ * D1 and the second control input τ * D2 This is the basis for calculating

[0073] First manipulated variable τ * D1 The first operation amount calculation unit 60 calculates the torque command τ * Capacitor voltage E to 0 cf The fluctuation component of e cf Multiplying by, the capacitor voltage E cf DC component (with underline) Ecf In other words, the first manipulated variable τ * D1 is the torque command τ0 * , τ1 * , or current command I * 1d ,I ** 1q and the capacitor voltage E cf The fluctuation component of e cf It is calculated according to.

[0074] Second control variable τ * D2 The second operation amount calculation unit 70 calculates the capacitor voltage E cf DC component (with underline) E cf and the capacitor voltage E cf The fluctuation component of e cf The second manipulated variable τ is a value obtained by multiplying the second manipulated variable τ by a proportional constant 71 and dividing the result by the rotation speed ωr of the induction motor 5. In other words, the second manipulated variable τ * D2 is the rotation speed ω of the electric motor 5 r and the capacitor voltage E cf The fluctuation component of e cf It is calculated according to.

[0075] The purpose of this device 10A is to measure the capacitor voltage E cf The object of the present invention is to obtain a certain damping characteristic for the vibration of the torque command τ * As a result, the device 10A calculates the damping characteristic of the damping control by using the voltage of the DC overhead line 1 and the torque command τ * 0 and the rotation speed ω of the induction motor 5 r It is no longer affected by any of these variable factors.

[0076] In other words, the present device 10A can obtain a constant damping characteristic that is not dependent on the operating points of each of the conventional fluctuation factors, and can realize stable control. This is theoretically derived from the above formula (23). In this way, according to the present device 10A of the first embodiment, the voltage of the DC overhead line 1 and the torque and rotation speed ω rThe capacitor voltage E cf As a result, in an electric railway to which the device 10A is applied, induction interference due to return current can be reduced, and the reactor 2 and capacitor 3 used in the filter circuit can be made smaller and lighter.

[0077] Furthermore, this alleviates restrictions on the mounting position due to the weight balance within and between vehicles when the device 10A is mounted under the vehicle floor, improving the freedom of design of the entire vehicle. EXAMPLES

[0078] FIG. 3 is a functional block diagram showing the device 10B according to the second embodiment, and shows only the differences from the device 10 in FIG. 1. Therefore, the same reference numerals are used for the parts common to the first embodiment in FIG. 1 and FIG. 2, and the description thereof is omitted. The device 10A in the first embodiment receives a torque command τ * 0 and d-axis magnetic flux command Φ * 2d On the other hand, the device 10B of the second embodiment receives a d-axis current command I * 1d and the q-axis current command I * 1q Receive.

[0079] The damping control unit 11, the adder 12, the current command calculation unit 21, the current control unit 22, and the slip frequency calculation unit 23 in the first embodiment are replaced with a damping control unit 111, an adder 112, a magnetic flux command calculation unit 121, a current control unit 122, and a slip frequency calculation unit 123, respectively. The magnetic flux command calculation unit 121 calculates a d-axis current command I * 1d From the circuit constants of the induction motor 5, the d-axis magnetic flux command Φ is calculated according to the following equation (24). * 2d Calculate the following.

[0080]

number

[0081] The damping control unit 111 controls the voltage E cf Damping control amount I to suppress vibration * qd The adder 112 generates a q-axis current command I that the device 10A receives from a higher-level control system (not shown) in order to generate a driving force required to accelerate or decelerate the vehicle. * 1q The damping control unit outputs the damping operation amount I * qD The q-axis current command I ** 1q Calculate.

[0082] The current control unit 122 controls the d-axis current I 1d and the q-axis current I 1q are the d-axis current command I * 1d and the q-axis current command I ** 1q In order to match this, the d-axis voltage command V d * and the q-axis voltage command V q * Generate.

[0083]

number

[0084] In order to match the direction of the d-axis with the direction of the rotor interlinkage magnetic flux of the induction motor 5, the slip frequency calculation unit 123 calculates the rotational angular velocity of the rotor interlinkage magnetic flux of the induction motor 5 and the angular velocity ω inv The slip frequency calculation unit 123 estimates the slip frequency, which is the difference between the d-axis magnetic flux command Φ * 2d and the q-axis current command I ** 1q From the circuit constants of the induction motor 5, the slip frequency estimate ω *s Generate.

[0085]

number

[0086] 4 is a detailed control circuit diagram of the damping control section 111 in FIG. 3. The damping control section 111 mainly controls the capacitor voltage E cf DC component of (with underline) E cf The control circuit 100 includes a low pass filter (LPF) 150 that extracts the input signal, an adder 151, a first manipulated variable calculation unit 160, and a second manipulated variable calculation unit 170. The control circuit 100 includes a divider 161 and a multiplier 162.

[0087] The first operation amount calculation unit 160 calculates the q-axis current command I * 1q The capacitor voltage E cf The fluctuation component of e cf Multiplying by, the capacitor voltage E cf DC component of (with underline) E cf This value is the first control variable I * qD1 The second operation amount calculation unit 170 calculates the capacitor voltage E cf DC component of (with underline) E cf and the capacitor voltage E cf The fluctuation component of e cf Multiplying this by the proportional constant 171 gives the rotation speed ω r Then, the d-axis magnetic flux command value M / L2Φ is calculated by dividing the * 2d This value is the second control variable I * qD2 It is.

[0088] The second operation amount calculation unit 170 calculates the rotation speed ω r and the stator-converted d-axis magnetic flux command value M / L2Φ * 2d Instead of division by q-axis voltage command V q *The damping control unit 111 may calculate the second manipulated variable by dividing the first manipulated variable I * qD1 and the second control variable I * qD2 By adding these values ​​in the adder 151, the damping operation amount I * qD is calculated.

[0089] In the drive control device, when the vector control of the induction motor 5 is established, the q-axis current I 1q It is generally known that the q-axis current command I * 1q On the other hand, when the damping operation amount is added, the same effect as in the first embodiment can be obtained. EXAMPLES

[0090] FIG. 5 is a functional block diagram showing an outline of a vehicle drive control device (this device) 10C according to a third embodiment of the present invention, and shows only the differences from the device in FIG. 1. Therefore, the same reference numerals are used for the parts common to the first embodiment in FIG. 1 and FIG. 2, and the description is omitted. In the first embodiment, the damping operation amount is set to a torque command τ0 * and is given to the vector control unit 20, whereas in the third embodiment, the damping operation amount is the q-axis voltage command V q * is added to.

[0091] 1 includes a damping control unit 11, an adder 12, a current command calculation unit 21, a current control unit 22, a slip frequency calculation unit 23, a phase calculation unit 24, and a PWM waveform generator 25. As if correspondingly replaced by these, a present device 10C in the third embodiment of FIG. 5 includes a damping control unit 211, an adder 212, a current command calculation unit 221, a current control unit 222, a slip frequency calculation unit 223, a phase calculation unit 224, and a PWM waveform generator 225.

[0092] The damping control unit 211 controls the voltage E cf The damping operation amount V to suppress the vibration of qD * The adder 212 generates the q-axis voltage command V q * For the damping operation amount V qD * Adding this, the q-axis voltage command V q ** and provides it to the PWM waveform generating unit 225.

[0093] The current control unit 122 controls the d-axis current I 1d and the q-axis current I 1q are the d-axis current command I * 1d and the q-axis current command I ** 1q In order to match this, the d-axis voltage command V d * and the q-axis voltage command V q * The current control unit 222, the slip frequency calculation unit 223, and the phase calculation unit 224 in FIG. 5 are similar to the current control unit 22, the slip frequency calculation unit 23, and the phase calculation unit 24 in FIG. 1, respectively. The PWM waveform generation unit 225 generates the q-axis voltage command V q * Instead of q-axis voltage command V q ** This is similar to the PWM waveform generating unit 25 except that it uses the following:

[0094] Fig. 6 is a detailed control circuit diagram of the damping control unit 211 in Fig. 5. The damping control unit 211 is mainly composed of a q-axis current manipulated variable calculation unit 250 and a multiplier 251. The q-axis current manipulated variable calculation unit 250 has a similar configuration to the damping control unit 111 and calculates the q-axis current manipulated variable I * qD The multiplier 251 generates the q-axis current control amount I * qD Substituting the circuit constants of the induction motor 5 into the following equation (28), the primary conversion resistance R σ Multiplying by this, the damping operation amount V qD** Calculate.

[0095]

number

[0096] The damping operation amount V in the damping control unit 211 qD * The calculation of may be a simple multiplication by the multiplier 251 as in the third embodiment, or the q-axis current control amount I * qD The transient response may be improved by adding a time derivative of the above.

[0097] In the third embodiment, the damping control unit 211 controls the damping operation amount V qD * However, taking into consideration the electromagnetic interference between the d-axis and q-axis quantities inside the induction motor 5, the d-axis voltage command V d * The damping control amount to be added to the output of the PWM waveform generating unit 225 may be output.

[0098] In addition, taking into consideration the effect of damping control on the slip frequency of the induction motor 5, the slip frequency estimate value ω * s Alternatively, the damping control unit 224 may output a damping control amount to be added to the phase angle θ of the three-phase AC voltage and provide it to the PWM waveform generation unit 225. 1d and the q-axis current I 1q In consideration of the influence on the d-axis current I 1d and the q-axis current I 1q Alternatively, the compensation amount to be added to the current control unit 222 may be calculated and provided to the current control unit 222.

[0099] As in Example 3, the q-axis voltage command V q * Even if the damping operation amount is added to the damping operation amount V qD * The q-axis current I caused by1q The change in the q-axis current control amount I * qD If they match, the same effect as in the first embodiment can be obtained based on the same principle as in the second embodiment.

[0100] In the first and second embodiments, the response angular frequencies ω acr is the resonant angular frequency ω of the filter circuit. n When the response angular frequency ω of the current control unit 222 is not sufficiently higher than the response angular frequency ω of the current control unit 222, the response delay of the output torque τ of the induction motor 5 cannot be ignored, and it may be difficult to ensure the control stability. acr This is particularly useful because it provides damping control independent of the EXAMPLES

[0101] 7 is a schematic circuit diagram of a fluctuation detection unit 330 according to a fourth embodiment of the present invention, and shows only the differences from the fluctuation detection unit 30 of the device 10A in FIG. 1. Therefore, the same reference numerals are used for the common parts with the first embodiment in FIG. 1 and FIG. 2, and the description is omitted. In the first embodiment, the capacitor voltage E cf The fluctuation component of e cf In contrast, in Example 4, the reactor current I s The fluctuation component i s Extract.

[0102] The fluctuation detection unit 30 in the first embodiment is replaced with a fluctuation detection unit 330. The fluctuation detection unit 330 mainly detects the reactor current I s The fluctuation component i s The characteristics of the bandpass filter 331 may be the same as those of the bandpass filter 31, or may be a filter that extracts the fluctuation component i s The amplitude and phase of the capacitor voltage E cf The fluctuation component of e cf The characteristic may be such that the value is converted to a value equivalent to EXAMPLES

[0103] 8 is a schematic circuit diagram of a fluctuation detection unit 430 according to a fifth embodiment of the present invention, and shows only the differences from the fluctuation detection unit 30 of the device 10A in FIG. 1. Therefore, the same reference numerals are used for the common parts with the first embodiment shown in FIG. 1 and FIG. 2, and the description is omitted. In the first embodiment, the capacitor voltage E cf The fluctuation component of e cf In contrast, in Example 5, the reactor voltage V L The fluctuation component of v L Extract.

[0104] The fluctuation detection unit 30 in the first embodiment is replaced with a fluctuation detection unit 430. The fluctuation detection unit 430 mainly detects the reactor voltage V L The fluctuation component of v L The characteristics of the bandpass filter 431 may be the same as those of the bandpass filter 31, or may be a filter that extracts the fluctuation component v of the reactor voltage. L The amplitude and phase of the capacitor voltage E cf The fluctuation component of e cf The characteristic may be such that the value is converted to a value equivalent to EXAMPLES

[0105] FIG. 9 is a diagram showing only the parts of a drive control device (present device) 10F according to the sixth embodiment that are different from the present device 10A of the first embodiment shown in FIG. Explanation of the parts common to the first embodiment will be omitted. The present device 10A of the first embodiment has a first manipulated variable τ * D1 and the second control input τ * D2 By adding these values ​​by an adder 51, the damping operation amount τ * D In contrast, the present device 10F of the sixth embodiment uses a pre-calculated table to calculate the first manipulated variable τ * D1 and the second control variable τ * D2 By referring to the damping operation amount τ * D Get the.

[0106] In the device 10F of the sixth embodiment, the adder 51 in the first embodiment shown in FIG. 1 is replaced with a table reference unit 551. The table reference unit 551 calculates a first manipulated variable τ * D1 and the second control input τ * D2 The device 10F refers to the table data 552 according to each value. Based on the reference value, the device 10F determines the damping operation amount τ * D The table data 552 calculates the first manipulated variable τ * D1 The damping control amount may have either a characteristic of simply adding the first control amount and the second control amount, or a characteristic of limiting the value of the damping control amount so that it does not exceed a predetermined upper limit or lower limit.

[0107] Furthermore, multiple types of table data 552 may be prepared and switched depending on the section the vehicle travels on. Alternatively, when multiple vehicles are coupled for operation, multiple types of table data 552 may be switched depending on the number and type of the coupled vehicles. Table reference unit 551 may perform simple linear interpolation processing on table data 552, or may perform interpolation processing such as higher-order polynomial interpolation, or may not perform any interpolation processing at all.

[0108] The present device 10 can be summarized as follows. [1] This device 10 is a vehicle drive control device that drives an electric motor 5 by controlling a power conversion circuit 4 connected to a DC power source 1 with a vector control unit 20. This device 10 includes a filter circuit, a fluctuation detection unit 30, 330, 430, a torque control unit (not shown), the power conversion circuit 4, and a damping control unit 11, 111, 211.

[0109] The filter circuit is interposed between the DC power source 1 and the DC side of the power conversion circuit 4. This filter circuit is configured with a reactor 2 and a capacitor 3, and prevents the outflow of harmonics. The fluctuation detection unit 30, 330, 430 detects the fluctuation component e of the electric quantity of the filter circuit. cfThe main function of the vector control unit 20 in FIG. 1 is a torque control unit (not shown). The torque control unit detects a torque command τ0 * , τ1 * , or current command I * 1d ,I ** 1q In response to this, the voltage command V applied to the motor 5 is * U ,V * V ,V * W Generate.

[0110] The power conversion circuit 4 outputs a voltage command V * U ,V * V ,V * W In response to the above equation (23), the damping control unit 11, 111, 211 converts the power of the DC power supply 1 into three-phase AC, forms a desired rotating magnetic field, and supplies it to the electric motor 5. * D1 and the second control input τ * D2 The sum of damping operation amount τ * D By operating the power conversion circuit 4 in accordance with cf Suppress.

[0111] First manipulated variable τ * D1 Before the addition process 51 in FIG. * D1 As shown in the figure, the torque command τ0 * , τ1 * Or, current command I * 1d ,I ** 1q and the fluctuation component e cf The second operation amount τ * D2 Before the addition process 51 in FIG. * D2 As shown in the figure, the rotation speed information of the electric motor 5 and the fluctuation component e cf Calculated according to:

[0112] The first term in the above equation (23) is the torque command τ * 0 and the capacitor voltage E cf The fluctuation component of e cf The second term of the above equation (23) is proportional to the rotation speed ω r These are inversely proportional to the first operation amount τ * D1 , and the second manipulated variable τ * D2 It is.

[0113] That is, the present device 10 is * D1 and the second control input τ * D2 Both of these are used as the torque command τ * By adding it to 0, the capacitor voltage E cf This constant damping is achieved by the damping control, which provides a constant damping to the vibration of the DC overhead line 1 and the torque command τ * 0 and rotation speed ω r As a result, the present device 10 can achieve stable damping control without being affected by changes in the driving state of the vehicle or the voltage environment.

[0114] [2] In the above [1], the damping operation amount τ * D The first operation amount τ is calculated from pre-calculated table data 552 as shown in FIG. * D1 and the second manipulated variable τ * D2 The second is the reference value obtained according to the first manipulated variable τ * D1 and the second manipulated variable τ * D2 is the sum of the above.

[0115] The device 10 can easily realize ideal damping control by executing a program stored in the memory of a computer. The computer may be a one-chip microcomputer or a personal computer, and may be used for other purposes. It is also preferable that the table data 552 stored in the memory is updatable.

[0116] [3] In the above [1], the amount of electricity may be at least one of the following three types. The first type is the basic type shown in Figures 1 and 2, and the amount of electricity is the voltage E of the capacitor 3. cf The second electrical quantity is the current flowing through the reactor 2 as shown in FIG. 7. The third electrical quantity is the voltage across the reactor 2 as shown in FIG. 8. In the present device 10, the capacitor voltage E cf The vibration phenomenon is caused by the current of reactor 2, the voltage across it, or the voltage E of capacitor 3. cf Since the fluctuation detection units 30, 330, and 430 perform detection over the shortest wiring distance, more accurate damping control can be easily achieved.

[0117] [4] In the above [1], the first manipulated variable τ * D1 If at least one of the following two conditions is true, the fluctuation component e cf The first is the first control amount τ * D1 The torque command τ0 * , τ1 * or current command I * 1d ,I ** 1q and the fluctuation component e cf As a result, the vector control unit 20 can perform damping control in a direction that counters the magnitude of the fluctuation cause and suppresses it. The second is that, as shown in the division process 61 in FIG. 2, the first manipulated variable τ * D1 The voltage E of capacitor 3 cf DC component (with underline) E cf As a result, the device 10 makes the capacitor voltage Ecf It is possible to perform damping control in a direction that suppresses the vibration phenomenon itself.

[0118] [5] In the above [1], as shown in the multiplication process 72 of FIG. 2, the second manipulated variable τ * D2 The first one is a fluctuation component e inversely proportional to the rotation speed information of the electric motor 5, including the sensorless type. cf The second is proportional to the voltage command V * U ,V * V ,V * W is inversely proportional to the fluctuation component e cf The third is proportional to the voltage E of capacitor 3. cf DC component (with underline) E cf In the device 10, the vector control unit 20 is configured to make the voltage command V * U ,V * V ,V * W is small, and the capacitor voltage E cf The greater the vibration or the cause of the fluctuation, the greater the effect of the fluctuation. Therefore, damping control is possible to counteract the magnitude of the fluctuation and suppress it.

[0119] [6] In the above [1], the second operation amount calculation unit 70 calculates the second operation amount τ * D2 The proportional constant 71 used in the calculation of the capacitor voltage E may be always a constant value, or may be switched according to the operation delay of the inverter 4 and the vector control unit 20, taking into account such a control delay. cf This enables agile damping control with little control delay for vibrations.

[0120] [7] In the above [1] to [6], the motor 5 may be an AC motor 5, and the power conversion circuit 4 may be an inverter 4 that converts the voltage of the DC power supply 1 into a three-phase AC voltage. Furthermore, the torque control unit controls the output torque τ of the motor 5 or the current flowing through the motor 5 to be equal to or greater than the torque command τ0. * , τ1 * or current command I * 1d ,I ** 1q The voltage command V * U ,V * V ,V * W Such a device 10 has good compatibility, compatibility with existing resources and existing technologies, and is easy to maintain, so it is highly practical and easy to maintain high performance. [Explanation of symbols]

[0121] 1: DC overhead line (DC power source), 2: reactor, 3: capacitor, 4: inverter, 5: induction motor 5, 10: vehicle drive control device (this device), 11, 111, 211: damping control unit, 12, 112, 212: adder, 20: vector control unit, 21, 221: current command calculation unit, 121: magnetic flux command calculation unit, 22, 122, 222: current control unit, 23, 123, 223: slip frequency calculation unit, 24, 224: phase calculation unit, 25, 225: PWM waveform generator, 26: coordinate transformation unit unit), 30, 330, 430: fluctuation detection unit, 31, 331, 431: band pass filter, 50, 150: low pass filter, 250: q-axis current manipulated variable calculation unit, 51, 151: adder (addition process), 251: multiplier, 60, 160, 560: first manipulated variable calculation unit, 61, 161: divider, 62, 162: multiplier, 70, 170, 570: second manipulated variable calculation unit, 71, 171: proportional constant, 72, 73, 172, 173: multiplier, 551: table reference unit, 552: table data, E cf : Capacitor voltage, (with underline) E cf :(Capacitor voltage E cf ) DC component, e cf :(Capacitor voltage E cf ) fluctuation component, e s : Fluctuation component (of the voltage of DC overhead line 1), I * 1d :d-axis current command, I * 1q:q-axis current command, I U ,I V ,I W :Phase current, K D :(Capacitor voltage E cf and its fluctuation component e cf proportionality constant, L1, L2: rotor self-inductance, M: mutual inductance, M / L2Φ * 2d : d-axis magnetic flux command value, N p : Number of pole pairs, P inv : (power drawn from the DC side by inverter 4), R1R2: rotor resistance, s: Laplace operator, τ: output torque, τ0 * , τ1 * : Torque command, τ D * : damping operation amount, τ * D1 : the first manipulated variable, τ * D2 : The second control variable, V * U ,V * V ,V * W : Voltage command, Φ * 2d : d-axis magnetic flux command, ζ: damping coefficient, σ: leakage coefficient, ω acr : Response angular frequency (of current control section 22), ω inv : Angular velocity (output from inverter 4), ω n : (filter circuit) resonant angular frequency, ω r :rotation speed, ω r τ / N p : Mechanical output, ω * s : Estimated slip frequency

Claims

1. a power conversion circuit connected to a DC power source and configured to supply power from the DC power source to an electric motor in response to a voltage command; a filter circuit interposed between a DC side of the power conversion circuit and the DC power supply, the filter circuit including a reactor and a capacitor; a fluctuation detection unit for detecting a fluctuation component of an electric quantity related to the filter circuit; a torque control unit that generates the voltage command to be applied to the electric motor in response to a torque command or a current command; a damping control unit that operates the power conversion circuit so as to suppress the fluctuation component; A vehicle drive control device comprising: The damping control unit is a first manipulated variable calculated in accordance with the torque command or the current command and the fluctuation component; a second manipulated variable calculated in accordance with rotation speed information of the electric motor and the fluctuation component; and operating the power conversion circuit according to a damping operation amount based on the A drive control device for a vehicle.

2. The damping operation amount is A reference value obtained from pre-calculated table data according to the first operation amount and the second operation amount; an added value of the first operation amount and the second operation amount; At least one of the following: The vehicle drive control device according to claim 1 .

3. The electrical quantity is at least one of a voltage of the capacitor, a current flowing through the reactor, and a voltage across the reactor.

3. The vehicle drive control device according to claim 1 or 2.

4. the first operation amount is proportional to the torque command or the current command and the fluctuation component, or is inversely proportional to a DC component of the voltage of the capacitor; The vehicle drive control device according to any one of claims 1 to 3.

5. The second operation amount is The fluctuation component is inversely proportional to the rotation speed information of the electric motor, and A case in which the fluctuation component is inversely proportional to the voltage command and proportional to the fluctuation component. The case where the capacitance is proportional to the DC component of the voltage of the capacitor, At least one of the following: The vehicle drive control device according to any one of claims 1 to 4.

6. a proportionality constant used in calculating the second manipulated variable is switched depending on a control delay of the torque control unit; The vehicle drive control device according to any one of claims 1 to 5.

7. the electric motor is an AC electric motor, the power conversion circuit is an inverter that converts the voltage of the DC power supply into a three-phase AC voltage, and the torque control unit is a vector control system that generates the voltage command so that the output torque of the electric motor or the current flowing through the electric motor coincides with the torque command or the current command. The vehicle drive control device according to any one of claims 1 to 6.

8. A filter circuit including a reactor and a capacitor is used, The filter circuit is interposed between a DC side of a power conversion circuit linked to a DC power source and the DC power source to prevent outflow of harmonics; the power conversion circuit supplies power from the DC power supply to an electric motor in response to a voltage command; a fluctuation detection unit detects a fluctuation component of an electric quantity related to the filter circuit; a torque control unit that generates the voltage command to be applied to the electric motor in response to a torque command or a current command; A damping control unit operates the power conversion circuit so as to suppress the fluctuation component, A vehicle drive control method for driving the electric motor, comprising: The damping control unit is a first manipulated variable calculated in accordance with the torque command or the current command and the fluctuation component; a second manipulated variable calculated in accordance with rotation speed information of the electric motor and the fluctuation component; and operating the power conversion circuit according to a damping operation amount based on the A drive control method for a vehicle.

9. The damping control unit is Regarding the damping operation amount, A reference value obtained from pre-calculated table data according to the first operation amount and the second operation amount; an added value of the first operation amount and the second operation amount; Using at least one of Controlling the power conversion circuit.

9. The vehicle drive control method according to claim 8.

10. The electrical quantity is at least one of a voltage of the capacitor, a current flowing through the reactor, and a voltage across the reactor.

10. The vehicle drive control method according to claim 8 or 9.

11. the first operation amount is proportional to the torque command or the current command and the fluctuation component, or is inversely proportional to a DC component of the voltage of the capacitor; The vehicle drive control method according to any one of claims 8 to 10.

12. The second operation amount is The fluctuation component is inversely proportional to the rotation speed information of the electric motor, and A case in which the voltage is inversely proportional to the voltage command and proportional to the fluctuation component. The case where the capacitance is proportional to the DC component of the voltage of the capacitor, At least one of the following: The vehicle drive control method according to any one of claims 8 to 11.

13. a proportionality constant used in calculating the second manipulated variable is switched depending on a control delay of the torque control unit; The vehicle drive control method according to any one of claims 8 to 12.

14. The electric motor is an AC electric motor, the power conversion circuit is an inverter that converts the voltage of the DC power supply into a three-phase AC voltage, and the torque control unit is a vector control system that generates the voltage command so that the output torque of the electric motor or the current flowing through the electric motor coincides with the torque command or the current command. The vehicle drive control method according to any one of claims 8 to 13.

Images