JP6532546B2 - Controller of rotating electric machine drive system - Google Patents

Description

  The present invention relates to a control device of a rotary electric machine drive system that controls a rotary electric machine by an inverter circuit.

Electric vehicles such as hybrid cars, electric cars, and fuel cell cars have rotating electric machines for driving, and there is an increasing demand for lower voltage and smaller size and higher output of the electric machines.
Generally, the normal current applied to the rotating electrical machine mainly includes the current density and calorific value of the stator coil, the magnetic saturation of the stator core and the rotor core, the capacity of the power device of the inverter circuit and the calorific allowance, etc. It is limited to a preset maximum rating in consideration of the calorific value, its safety factor and the allowable duration. Then, an excessive current exceeding the maximum rating is temporarily applied from the inverter circuit to the rotating electrical machine to increase the rotational torque.

  According to Patent Document 1, when receiving a large torque generation command requiring generation of a rotational torque larger than the maximum rating of sinusoidal wave drive, control to shift to the non-sinusoidal wave drive mode to increase the rotational torque of the rotating electrical machine Technology is shown.

JP, 2009-303289, A

It is necessary to appropriately protect the power device of the inverter circuit from heat and surge voltage generated when an excessive current is applied from the inverter circuit to the rotating electrical machine.
The present invention has been made in view of the above-described point, and an object of the present invention is to provide a rotation device capable of appropriately protecting a power device of an inverter circuit when an excessive current is applied to the rotating electric machine from the inverter circuit. It is providing a control device of an electric machine drive system.

  A controller for a rotary electric machine drive system according to the present invention, which solves the above-mentioned problems, comprises: a rotary electric machine having a stator formed of N (N is an integer of 3 or more) phase coils; An inverter circuit having a power device for applying a voltage, the control device of a rotary electric machine drive system comprising: a control unit for performing PWM control of the power device, the inverter circuit including an input terminal of the power device and the power A clamp circuit that is energized when a voltage higher than a predetermined voltage is applied between the device and the gate terminal of the device, and the control unit performs the PWM control before the energized state when the clamp circuit is energized. The frequency of the PWM control in the current-carrying state is lower than the frequency of the frequency.

  According to the present invention, the power device of the inverter circuit can be appropriately protected from heat or surge voltage generated when an excessive current is applied from the inverter circuit to the rotating electrical machine. In addition, the subject except having mentioned above, a structure, and an effect are clarified by description of the following embodiment.

FIG. 6 is an output diagram of a three-phase alternating current rotating electric machine when the rotational torque is increased to achieve high output. System block diagram of a hybrid vehicle. The figure which shows the inverter circuit of 3 phase alternating current. The figure which shows an example of a clamp circuit. The figure which shows an example of a rotary electric machine. The figure which extracted one part of the stator iron core which the multiphase stator coil was wound in the elements on larger scale of FIG. Operation | movement figure of a power device when inputting an excessive current into an inverter circuit, without attaching a clamp circuit. Operation | movement progress figure of a power device when an excessive current is input into the inverter circuit which attached the clamp circuit. The figure which showed that the influence of the surge voltage at the time of using a clamp circuit when the carrier wave is high frequency remains. The figure which showed that the influence of the surge voltage at the time of using a clamp circuit can be minimized, when a carrier wave is low frequency. The flowchart which demonstrates the operation | movement series of this invention. Operation determination circuit diagram of the clamp circuit. Fig. 5 is a flow chart illustrating a process for responding to an acceleration request while making application decisions of the present invention.

  FIG. 1 is an output diagram of a three-phase alternating current rotating electric machine when the rotational torque is increased to achieve high output. There are two methods to increase the rotational torque of the three-phase AC rotating electrical machine: increasing the amount of magnets and increasing the current, but we would like to avoid the method of increasing the amount of magnets. This is because it is desirable to avoid an increase in the induced voltage during driving from the viewpoint of voltage reduction requirements. Therefore, a method of increasing the torque by increasing the current supplied from the inverter circuit to the rotating electrical machine is employed.

  In general, the rotational torque of the rotary electric machine 300 is limited to the maximum rating 301 as shown by the solid line in FIG. Factors affecting the limitation are the current density and calorific value of the stator coil 311 of the rotating electrical machine 300, the magnetic saturation of the stator core 312 and the rotor core 321, and the capacity and calorific allowance of the power device 201 of the inverter circuit 200. Etc, mainly the calorific value and its safety factor and the permissible duration.

  In order to obtain the critical rating 303 of the critical rating area 302 shown in FIG. 1 beyond the maximum rating 301, it is necessary to apply an overcurrent. The critical rating area 302 is mainly expected to be an auxiliary application at the time of vehicle start. The reason is that there is a risk that too strong rotational torque will be generated when used during normal acceleration. Therefore, the use duration time of the critical rating area 302 assumes a few seconds immediately after the start as the main use range.

  Then, the measures against heat generation and protection method of the power device 201 of the inverter circuit 200 against the heat generated when the excessive current is applied are the major problems. That is, the subject of the present invention is measures against heat generation and protection method of the power device 201 at the time of excessive current input.

FIG. 2 is a system block diagram of a hybrid vehicle.
The present invention is an invention that is particularly applicable to the rotating electrical machine 300 for driving the hybrid vehicle 101.

  The hybrid vehicle 101 shown in FIG. 2 has a parallel type drive system capable of transmitting at least one rotational torque to the drive wheels 504 by coordination of the rotating electrical machine 300 and the fuel injection type engine 500. However, the present invention is not limited to the application to the parallel hybrid vehicle 101. The present invention can be widely used in electric vehicles (hybrid vehicles, electric vehicles, fuel cell vehicles) using a rotating electrical machine.

  Hybrid vehicle 101 starts traveling with, for example, the rotational torque of rotating electric machine 300 as the main power. At this time, the clutch 501 is in the connected state. Then, when the vehicle speed increases, the fuel injection engine 500, which is an internal combustion engine, starts. Thereafter, the hybrid vehicle 101 can continue traveling with the rotational torque generated by the fuel injection type engine 500 as a main driving force.

  The rotational torque generated by the rotating electrical machine 300 and the fuel injection type engine 500 is transmitted to the drive wheel 504 via the transmission 502 and the differential gear 503. The rotary electric machine 300 may generate a rotational torque so as to assist the rotational torque of the fuel injection type engine when high rotational torque is required, such as acceleration or climbing.

  During the regenerative braking operation, the rotary electric machine 300 generates AC power based on the rotational torque transmitted from the drive wheel 504. The generated AC power is converted into DC power by the inverter circuit 200 and charged in the power supply source 204. Then, the power charged in the power supply source 204 is used again as traveling energy.

  The inverter circuit 200 is electrically connected to the power supply source 204 via the power cable 205. Then, the exchange of electric power is performed between the electric power supply source 204 and the inverter circuit 200. When operating the rotating electrical machine 300 as a motor, the inverter circuit 200 converts DC power supplied from the power supply source 204 via the power cable 205 into AC power, and supplies the AC power to the rotating electrical machine 300.

FIG. 3 is a diagram for explaining the configuration of the drive system of the rotating electrical machine.
The rotating electrical machine drive system includes an inverter circuit 200, a rotating electrical machine 300, and a control device 400. The inverter circuit 200 has, for example, a three-phase alternating current inverter circuit shown in FIG.

  The inverter circuit 200 has a power device 201 that applies an N-phase AC voltage to the stator. The power device 201 used in the inverter circuit 200 can be divided into a MOS field effect transistor (MOS-FET) and an insulated gate bipolar transistor (IGBT) depending on the breakdown voltage and the applied voltage. However, this does not exclude the use of other power devices.

  The leg 206 per phase of the inverter circuit 200 includes a power device and a diode (hereinafter, power device for upper arm or power device) operating as an upper arm, and a power device and a diode (hereinafter, below) operating as a lower arm. It is comprised by series connection of the power device for arms, or power device) 201b.

  The inverter circuit 200 includes the legs 206 respectively corresponding to three phases of U-phase, V-phase, and W-phase of AC power to be output. These three phases correspond to the three-phase windings of the stator coil 311 of the rotary electric machine 300 (see FIG. 5).

  Each of the three-phase legs 206 outputs an alternating current from each of the intermediate electrodes 207 to each phase winding of the rotary electric machine 300 via the power cable 205 or an AC bus bar (not shown). The terminal of the upper arm power device 201 a not connected to the intermediate electrode 207 is electrically connected to the positive electrode bus 208. A terminal of the lower arm power device 201 b not connected to the intermediate electrode 207 is electrically connected to the negative electrode bus 209.

  The positive electrode bus 208 and the negative electrode bus 209 are electrically connected to the smoothing capacitor 210. Furthermore, the positive electrode bus 208 and the negative electrode bus 209 are connected to the power supply source 204 via the power cable 205 or the like. The control device 400 is configured of a gate driver circuit 211 and a control circuit 212. Control device 400 receives a control command from higher-level control device 213 that determines, for example, the operation state of the driver of the vehicle.

  The control circuit 212 includes a control unit (microcomputer, also referred to as a microcomputer) (not shown) for performing arithmetic processing on the switching timing of each power device 201. The input information to the control unit includes, for example, a target rotation torque value required for the rotating electrical machine 300, a current value supplied from the inverter circuit 200 to the rotating electrical machine 300, and a magnetic pole position of the rotor 320 of the rotating electrical machine 300 There is.

  The control unit calculates the voltage command values of the U phase, the V phase, and the W phase based on the received control command and the sensed physical value. Then, the control unit generates a pulse-like modulation wave from the comparison between the fundamental wave (sine wave) and the carrier wave (triangle wave) based on the voltage command value of each phase, and generates the generated modulation wave by PWM (pulse width modulation). Signal) to the gate driver circuit 211 (PWM control).

  The gate driver circuit 211 generates drive pulses for controlling the power device 201 of each phase based on the PWM signal input from the control circuit 212 and supplies the drive pulse to the power device 201 of each phase.

  The power device 201 of each phase conducts and shuts off based on the drive pulse, converts the DC power supplied from the power supply source 204 into three-phase AC power, and supplies it to each phase of the rotary electric machine 300.

FIG. 4 is a diagram showing an example of the clamp circuit.
The clamp circuit 250 is provided in the vicinity of the power device 201. The clamp circuit 250 is energized when a voltage higher than a predetermined voltage is applied between the input terminal 202 and the signal input terminal 203 of the power device 201. The clamp circuit 250 has a role of suppressing a surge voltage generated when the power device 201 of the inverter circuit 200 switches. In addition to the above, the inverter circuit 200 includes an electromagnetic noise reduction filter (abbreviated as Y capacitor) (not shown) for a star-connected capacitor.

  The clamp circuit 250 has a recovery diode 215 and a zener diode for the clamp circuit. The input terminal 202 is connected to the positive electrode bus 208 when the power device 201 is the upper arm power device, and is connected to the intermediate electrode 207 disposed at one position for each phase in the lower arm power device. ing. The signal input terminal 203 is connected to the gate driver circuit 211. The output terminal 214 is connected to the intermediate electrode 207 when the power device 201 is a power device for the upper arm, and is connected to the negative electrode bus 209 in the power device for the lower arm.

FIG. 5 is a diagram showing an example of a rotating electrical machine.
The rotary electric machine 300 is a permanent magnet synchronous motor, and a permanent magnet synchronous motor using a magnet 322 such as neodymium is suitable. However, this does not exclude the use of other rotating electrical machines.

  The present invention can be widely applied to an induction motor, a reluctance torque motor, a generator, and the like. The rotary electric machine 300 not only generates rotational torque according to the driving method, but also has a function of converting mechanical energy externally applied to the rotary electric machine 300 into electric power.

The rotating electrical machine 300 shown in FIG. 5 is, for example, a concentrated winding type rotating electrical machine 305. However, this does not exclude winding systems other than concentrated winding. The rotating electrical machine 300 has a stator 310 and a rotor 320. The stator 310 is constituted by a phase coil of N (N is an integer of 3 or more) phase, and has a stator core 313.

  FIG. 6 is a partially enlarged view 306 of FIG. 5, and is a view in which a portion of the stator core 313 having the multiphase stator coil 311 wound is extracted. A multiphase stator coil 311 is wound around the stator core 313 one or more times. In the multiphase stator coil 311 wound a plurality of times around the stator core 313, one end 311a of the end is connected to any one of the U phase, V phase and W phase of the inverter device, and the other 311b is the other It is connected with the stator coil of the phase, and is collected as a neutral point (not shown). An insulating member 314 is inserted between the stator core 313 and the multiphase stator coil 311. The insulating member 314 corresponds to, for example, a resin-based component or an insulating paper.

  The rotor 320 is formed of a rotor core 321, a magnet 322 and a rotating shaft 323. The rotor core 312 is made of, for example, a silicon steel plate, and is responsible for fixing the magnet 322 and fastening with the rotation shaft 323. Magnet 322 is, for example, a permanent magnet, and is a magnet such as a ferrite magnet or neodymium.

  The stator 310 and the rotor 320 are housed, for example, in an aluminum casing or the like, and constitute a rotating electrical machine. The stator 310 and the rotor 320 are fastened to the vehicle body of the automobile through the aluminum casing. The rotary electric machine 300 is cooled by an air cooling system, a water cooling system, an oil cooling system, or a combination thereof.

  The current input to the power device 201 in the critical rating area 302 shown in FIG. 1 is a value exceeding the allowable current value of each power device 201. However, if the duration is extremely short, the durability of the power device 201 is not affected.

  FIG. 7 is an operation progress diagram of the power device 201 when an excessive current is input to the inverter circuit 200 without the clamp circuit 250 being attached.

  Generally, when the current is input to the power device 201 and switching off (power device off) occurs, a surge voltage 263 is generated in the voltage 262 between the input and output of the power device. The magnitude of the surge voltage 263 is proportional to the blocking input current 261. If the surge voltage 263 exceeds the allowable voltage limit 265 of the power device 201, the power device 201 may be damaged.

The reason for breaking the power device by interruption is electromagnetic energy of the wiring inductance. For example, if the input current limit rating 303 three times larger than the current maximum rating 301, the electromagnetic energy ratio becomes nine times (from Li ^2/2 (L is the inductance of the AC bus bar)).

  As shown in FIG. 7, turning off the power device generates a loss 266 but is not regarded as important for a short time or possibility of breakage of the power device 201.

  FIG. 8 is an operation progress diagram of the power device 201 when an excessive current is input to the inverter circuit 200 to which the clamp circuit 250 is attached.

  The surge voltage 264 generated in the input-output voltage 262 of the power device 201 is limited by the clamp circuit 250 at an upper limit, and therefore the voltage does not become enough to damage the power device 201.

  The clamp circuit 250 generates a loss 267 by the product of voltage, current and time. Therefore, the loss 267 of the clamp circuit 250 becomes larger as the duration time becomes longer. And since the power device 201 is heated by the loss 267, it may be thermally damaged.

  Therefore, in order to reduce the loss 267, the clamp circuit 250 is used, and the carrier wave (carrier frequency) is lowered. The switching loss caused by the carrier is because the carrier is smaller at lower frequencies. From the above, the loss 267 can be reduced to the loss 268.

  FIG. 9 is a diagram showing that the influence of the surge voltage remains when the clamp circuit is used when the carrier wave has a high frequency.

  Applying the clamp circuit 250 extends the time that the power device 201 is completely turned off. Therefore, as shown in FIG. 9, with the high frequency of the carrier wave, the effect of the surge voltage 264 suppressed by the clamp circuit 250 may remain at the time of the previous switching as the rotating electrical machine 300 has a higher rotation.

  However, if the carrier wave is low frequency, as shown in FIG. 10, it is possible to obtain a time in which the influence of the surge voltage 264 suppressed by the clamp circuit 250 can be minimized. Thus, the clamp circuit 250 can suppress the excessive increase of the voltage 262 between the input and the output of the power device, and can suppress the switching loss by reducing the carrier frequency, thereby minimizing the loss of the power device 201 and preventing the damage. When the clamp circuit 250 is in the conductive state, the control unit performs control to lower the frequency of the PWM control in the conductive state than the frequency of the PWM control before the conductive state.

  The present invention can be applied to all the rotating electrical machine drive systems in which the inverter circuit 200 using a carrier wave and the rotating electrical machine 300 are combined.

  FIG. 11 is a flow chart for explaining control for executing or canceling the reduction of the carrier frequency. In the following, when the clamp circuit 250 is in the energized state, a sequence for lowering the frequency of PWM control in the energized state compared to the frequency of PWM control in the energized state is defined as an on sequence, and the frequency of the PWM control is A sequence approaching the frequency of the PWM control before the energized state is defined as an off sequence.

  This process is applied only when an excessive current is applied to the rotary electric machine 300. The reason for limiting the region is that the low carrier frequency is a factor that deteriorates the vibration noise characteristics of the rotary electric machine 300. The on sequence 271 for reducing the carrier frequency is as follows. Each process switching determination is performed by the control unit, but may be configured using a logic circuit.

  When an excessive current is applied to the rotary electric machine 300, the control unit detects the excessive current based on, for example, a result of sensing by a current sensor (not shown) (272). The clamp circuit 250 is automatically operated when the voltage 262 between the input and output of the power device, which is fluctuated by the switching operation, exceeds a predetermined threshold.

  However, the control unit can not detect the start of the operation of the clamp circuit 250. Therefore, a circuit that causes the control unit to detect the operation of the clamp circuit 250 is required. For example, a circuit 252 illustrated in FIG. 12 is an operation determination circuit of the clamp circuit 250.

  In the circuit, a logic circuit is built so as to satisfy the truth table 254 from the signals at both ends of the buffer circuit 253 provided at the signal input terminal 203 of the power device 201. When the clamp circuit 250 is in operation, A is low and B is high. The logic circuit is constructed such that C is High at this condition. The result of C is taken into the control unit via, for example, a D / A converter (not shown). Then, the control unit determines that the clamp circuit 250 is in operation (273). As a result, an on sequence for lowering the frequency of the carrier wave is established (274).

Next, the triggering condition of the off sequence 275 will be specifically described.
First, the control unit detects the temperature of the power device 201 (276). The temperature of the power device 201 is an actual measurement temperature or an estimated temperature. The estimated temperature corresponds to, for example, a value calculated by a heat estimation model or an observer. The control unit compares the detected temperature with a predetermined temperature (e.g., a value obtained by subtracting the likelihood from the maximum operating temperature of the control unit).

  The control unit determines, based on the temperature information of the power device 201, whether or not the frequency of the PWM control approaches the frequency of the PWM control before the energized state of the clamp circuit 250. When the power device temperature is higher than a predetermined temperature, the control unit reduces the current flowing to the power device 201 by applying current limit to protect the power device 201. Then, the control unit warns the driver of the overheat signal. Then, the carrier frequency is changed to the carrier frequency at the time of normal control, which is determined according to the rotational speed of the rotary electric machine 300 (278).

  If the temperature of the power device 201 is lower than a predetermined temperature, the rotational torque of the critical rating area 302 is kept outputting for as long as possible. Therefore, the control unit does not change to the carrier frequency at the time of normal control until the activation condition of the off sequence 275 is satisfied in advance. Then, when the condition is satisfied, the carrier frequency (carrier frequency at the time of normal control) is calculated based on the current rotational speed of the rotary electric machine, and is returned to the calculated carrier frequency.

  An example of the triggering condition of the off-sequence 275 is shown below.

<Condition 1>
Condition example 1 is a method of using the operation determination circuit 252 of the clamp circuit.
First, the control unit confirms that the clamp circuit 250 is off. It is determined from the following method that the clamp circuit 250 is not operating. When the C column becomes low in the truth table 254, it is determined that the clamp circuit 250 is not operating.

  If it is determined that the clamp circuit is not operating, it is determined that the condition is satisfied (277). When the condition is satisfied, the control unit calculates the carrier frequency based on the current rotation speed of the rotary electric machine 300. Then, the control unit changes to the calculated carrier frequency and shifts to normal control (278). If the condition is not met, the process continues until the condition is met.

<Condition 2>
Condition example 2 is a method of using the operation determination circuit 252 of the clamp circuit.
The difference from Condition Example 1 is a determination method of determining that the clamp circuit 250 is not operating.

  First, the control unit detects the current input to the rotating electrical machine 300. The control unit compares the detected current with the current of the maximum rating 301. If the detected current is smaller than the current of the maximum rating 301, it is determined that the clamp circuit 250 is not operating. If it is determined that the clamp circuit is not operating, it is determined that the condition is satisfied (277). When the condition is satisfied, the control unit calculates the carrier frequency based on the current rotation speed of the rotary electric machine 300. Then, the control unit changes to the calculated carrier frequency and shifts to normal control (278). If the condition is not met, the process continues until the condition is met. Although not described, a hysteresis comparator may be used in the comparison determination.

<Condition 3>
Condition example 3 is a method using a timer.
The timer is, for example, incorporated as a program in the control unit. The timer starts counting up to N seconds at the moment when the operation of the clamp circuit 250 is detected or the carrier is changed to low frequency (N is a value of 0 or more).

  The control unit determines whether the frequency of the PWM control approaches the frequency of the PWM control before the energized state of the clamp circuit 250 based on the elapsed time from the start of the energized state of the clamp circuit 250. For example, when N seconds have elapsed, the control unit redetects the temperature of the power device 291. If the power device temperature is equal to or higher than the predetermined temperature, it is determined that the condition is satisfied (277). When the condition is satisfied, the control unit calculates the carrier frequency based on the current rotation speed of the rotary electric machine 300. Then, the control unit changes to the calculated carrier frequency and shifts to normal control (278). If the condition is not satisfied, the timer counts N seconds again from the moment when it is determined that the condition is not satisfied. When N seconds have elapsed, the control unit performs the same detection and comparison as described above.

<4>
Condition example 4 is a method using no load induced voltage.
For example, it is assumed that the application of the critical rating area 302 is the assist of the rotational torque of the fuel injection type engine 500 at the initial start. In this case, if the initial startup period of the fuel injection type engine 500 has passed, the rotational torque assist by the rotary electric machine 300 is unnecessary.

  When there is no powering command to the rotary electric machine 300 and the fuel injection type engine 500 is rotated from the outside, no load driving is performed. Therefore, the control unit can detect the no-load induced voltage from the terminal (not shown) of each phase of the rotary electric machine 300. The control unit determines from the rotational speed of the rotary electric machine 300 whether the rotational speed of the fuel injection type engine 500 is equal to or more than the rotational speed that can be stably driven from the no-load induced voltage. Alternatively, the rotational speed of the fuel injection type engine 500 may be directly detected and determined.

  The control unit determines whether the frequency of the PWM control approaches the frequency of the PWM control before the energized state of the clamp circuit 250, based on the rotational speed of at least one of the rotary electric machine 300 or the fuel injection type engine 500. The control unit determines that the condition is satisfied when the number of revolutions of the fuel injection type engine 500 can be stably driven or more (277). When the condition is satisfied, the control unit calculates the carrier frequency based on the current rotation speed of the rotary electric machine 300. Then, it changes to the calculated carrier frequency, and shifts to normal control (278). If the condition is not met, the process continues until the condition is met.

  FIG. 13 is a flow chart diagram illustrating the process of responding to high rotational torque output while making application decisions of the present invention.

  A high rotational torque request may come from the driver continuously. Under conditions of continuous high rotational torque output demand, the power device 201 may have already reached a high temperature after the second time.

  When detecting the high rotational torque request, the control unit calculates a necessary rotational torque command value (281). Then, it is determined whether the calculated rotational torque command value is in the limit rated area 302 (282). If the rotational torque command value is equal to or less than the maximum rating 301, the high rotational torque request is met without the application of the present invention.

  On the other hand, when the rotational torque command value is higher than the maximum rating 301, it is determined that the rotational torque in the critical rating area 302 has been requested. Next, the control unit determines whether low carrier frequency control is applied (283). This determination is made from the current carrier frequency or the operation determination circuit 252 of the clamp circuit. When the low carrier frequency control is not applied, the on sequence 271 of FIG. 11 is promptly executed (284).

  After the low carrier frequency control is applied, the control unit performs the execution determination of the off sequence 275 in FIG. 11 (285). When the power device 201 is already at high temperature, it immediately shifts to the off sequence 275. This can prevent an excessive temperature rise of the power device 201. If the off sequence 275 is not performed immediately, then it will still respond to the high torque demand.

  Even when the off-sequence 275 is executed and the high rotational torque request from the driver continues even after the carrier wave is increased in frequency, the rotational torque of the maximum rating 301 or less is detected while the temperature of the power device 201 is detected. Corresponding (286). That is, the control unit continues the off sequence 275 (286) if the condition of the on sequence 271 is satisfied while the off sequence 275 is being executed (285).

  When the high rotational torque request ends, the normal control is immediately shifted to even if any of the present processes are being executed. At this time, if the off sequence 275 is not executed, the off sequence 275 is executed and then the control shifts to the normal control.

  According to the above-described controller of the rotating electrical machine drive system, the power device of the inverter circuit can be appropriately protected from heat or surge voltage generated when an excessive current is applied from the inverter circuit to the rotating electrical machine.

  As mentioned above, although the embodiment of the present invention was explained in full detail, the present invention is not limited to the above-mentioned embodiment, and various designs are possible in the range which does not deviate from the spirit of the present invention described in the claim. It is possible to make changes. For example, the above-described embodiment has been described in detail in order to explain the present invention in an easy-to-understand manner, and is not necessarily limited to one having all the described configurations. Further, part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Furthermore, with respect to a part of the configuration of each embodiment, it is possible to add / delete / replace other configurations.

100 · · · rotating electrical machine drive system 101 · · · hybrid vehicle 200 · · · inverter circuit 201 · · · power device 201a · · · power device that operates as the upper arm and diode 201b · · · power device that operates as the lower arm And diode 202 ... input terminal 203 of power device ... signal input terminal 203 of power device
204: power supply source 205: power cable 206: leg 207 per phase: intermediate electrode (one for each phase)
208 ... positive electrode bus 209 ... negative electrode bus 210 ... smoothing capacitor 211 ... gate driver circuit 212 ... control circuit 213 ... superordinate controller 214 ... output terminal 215 of power device · · · Recovery diode 250 · · · clamp circuit 251 · · · Zener diode 252 for clamp circuit · · · · Operation determination circuit 253 for clamp circuit · · · buffer circuit 254 · · · Truth table 261 · · · · input of the power device Current 262: Voltage between power device input and output 263: Surge voltage (without clamp circuit)
264 ・ ・ ・ Surge voltage (without clamp circuit)
265: Allowable voltage limit of power device 266: Loss of power device (without clamp circuit)
267 ... Loss of power device (with clamp circuit)
268 ... Loss of power device (applicable to clamp circuit and low carrier frequency)
271: ON sequence 272: Excess current detection sequence 273: Clamp circuit operation determination sequence 274: Carrier frequency reduction sequence 275: OFF sequence 276: Power device temperature Detection sequence 277 ... confirmation sequence of activation condition of off sequence 278 ... transition sequence to normal control 281 ... calculation of rotational torque command value 282 ... determination sequence of limit rated area 283 ... Application determination sequence for low carrier frequency control 284 ... immediate execution sequence of on sequence 285 ... execution sequence for off sequence 286 ... correspondence sequence with rotational torque less than the maximum rating 300 ... rotating electrical machine 301 · · Maximum rating 302 · · · limit rating area 303 · · Critical rating 304 · · · Maximum rated operating area 305 · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · stator stator coil 311 · · · · stator coil 311a · · · stator coil End 311b of stator coil end of stator coil 312 stator core 313 stator core 314 insulation member 320 rotor 321 rotor core 322 magnet 323 ... Rotating shaft 400 ... Control device 500 ... Fuel injection type engine 501 ... Clutch 502 ... Transmission 503 ... Differential gear 504 ... Drive wheel

Claims (7)

A rotating electrical machine having a stator configured of phase coils of N (N is an integer of 3 or more) phases;
An inverter circuit having a power device for applying an N-phase AC voltage to the stator;
Control device for a rotating electrical machine drive system comprising:
A control unit that performs PWM control of the power device;
The inverter circuit has a clamp circuit that is energized when a voltage higher than a predetermined voltage is applied between an input terminal of the power device and a gate terminal of the power device,
In the rotating electrical machine drive system, the control unit lowers the frequency of the PWM control in the energized state compared to the frequency of the PWM control before the energized state when the clamp circuit is in the energized state. Control device.   The control unit determines whether the frequency of the PWM control approaches the frequency of the PWM control before the energization state of the clamp circuit based on temperature information of the power device. The control apparatus of the rotary electric machine drive system of Claim 1.   The control unit determines whether or not the frequency of the PWM control approaches the frequency of the PWM control before the energized state of the clamp circuit based on the number of rotations of the rotating electrical machine. The control apparatus of the rotary electric machine drive system of Claim 2.   The rotary electric machine according to any one of claims 1 to 3, wherein the control unit reduces the current supplied to the power device when the temperature of the power device is higher than a predetermined temperature. Drive system control device.   The control unit determines whether the frequency of the PWM control approaches the frequency of the PWM control before the energized state of the clamp circuit based on an elapsed time from the start time of the energized state of the clamp circuit. The control device of the rotary electric machine drive system according to claim 1, wherein: The rotating electrical machine drive system is driving in coordination with the engine,
The control unit determines whether the frequency of the PWM control approaches the frequency of the PWM control before the energization state of the clamp circuit based on the number of revolutions of the engine. The control device of the rotary electric machine drive system according to 1. When the clamp circuit is in the conductive state, a sequence for lowering the frequency of the PWM control in the conductive state than the frequency of the PWM control before the conductive state is defined as an on sequence.
A sequence for bringing the frequency of the PWM control close to the frequency of the PWM control before the energized state of the clamp circuit is defined as an off sequence,
The control device of a rotary electric machine drive system according to claim 1, wherein the control unit continues the off sequence when the condition of the on sequence is satisfied while executing the off sequence.

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