Regulation system and power conversion device

Abstract

An adjustment system (80) is provided with a power conversion device (1) and a signal generation device (75). The signal generation device (75) is provided outside the power conversion device (1). The power conversion device (1) includes a switching element (Q), a drive circuit (30), and a signal generation unit (45). The drive circuit (30) drives the switching element (Q). The signal generation unit (45) generates a drive signal (Vin) for controlling the switching timing of the switching element (Q). The signal generation device (75) is configured to generate an adjustment signal (Vref) for adjusting the switching speed of the switching element (Q) in accordance with the measurement result of the physical quantity of the power conversion device (1). The power conversion device (1) further includes a terminal (T2). The terminal (T2) is configured to receive the adjustment signal (Vref) from the signal generation device (75). The drive circuit (30) drives the switching element (Q) in accordance with the drive signal (Vin) and the adjustment signal (Vref).

Description

[Technical Field]

[0001] The present disclosure relates to regulation systems, power conversion devices, and methods. [Background technology]

[0002] BACKGROUND ART In recent years, semiconductor elements such as metal-oxide-semiconductor field-effect transistors (MOSFETs) and insulated gate bipolar transistors (IGBTs) have become widespread. These semiconductor elements can be mounted as switching elements in power conversion devices.

[0003] Japanese Patent Application Laid-Open Publication No. 2022-48884 (Patent Document 1) discloses a semiconductor module. This semiconductor module includes a switching element and a drive unit. The drive unit drives the switching element in response to a control signal for controlling the switching (on / off) of the switching element. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2022-48884 Summary of the Invention [Problem to be solved by the invention]

[0005] The magnitude of loss or noise of a power conversion device may deviate from the desired range (value) due to variations in parts during mass production, changes in the installation environment of the electrical equipment in which the device is installed, or deterioration of the device's parts over time. In such cases, after the power conversion device is manufactured, it is very time-consuming to replace the parts of the device or to reproduce another power conversion device so that the magnitude of loss or noise is the desired value.

[0006] The present disclosure has been made to solve the above-mentioned problems, and its purpose is to adjust the magnitude of loss or noise of a power conversion device to a desired magnitude using a simple method. [Means for solving the problem]

[0007] The adjustment system of the present disclosure includes a power conversion device and a signal generating device. The signal generating device is provided external to the power conversion device. The power conversion device includes a switching element, a drive circuit, and a signal generating unit. The drive circuit drives the switching element. The signal generating unit generates a first signal for controlling the switching timing of the switching element. The signal generating unit is configured to generate a second signal for adjusting the switching speed of the switching element in accordance with a measurement result of a physical quantity of the power conversion device. The power conversion device further includes an input terminal. The input terminal is configured to receive the second signal from the signal generating device. The drive circuit drives the switching element in accordance with the first signal and the second signal. [Effects of the Invention]

[0008] With the above configuration, a signal generator provided outside the power conversion device generates a second signal based on the measurement results of the physical quantities of the power conversion device. The second signal is input from the signal generator to the input terminal and used to drive the switching elements by the drive circuit. This allows the switching speed to be appropriately adjusted by the signal input from the signal generator without replacing or reproducing parts of the power conversion device. As a result, even if the magnitude of loss, noise, etc. of the power conversion device is not the desired magnitude after manufacturing, the magnitude of loss, noise, etc. can be easily adjusted to the desired magnitude. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a diagram illustrating an example of a configuration of a power conversion system according to an embodiment. [Figure 2] FIG. 1 is a diagram illustrating an example of a configuration of a power conversion device. [Figure 3] FIG. 2 is a diagram illustrating an example of a hardware configuration of a control device. [Figure 4] FIG. 2 is a diagram showing the basic configuration of a switching element, a main driving device, and a control device. [Figure 5] 10 is a diagram illustrating an example of the relationship between the voltage value of an adjustment signal and the voltage value of a drive capability signal. [Figure 6] FIG. 2 is a diagram illustrating an example of the configuration of a drive unit. [Figure 7] FIG. 7 is a diagram illustrating a configuration example of a resistance adjusting circuit shown in FIG. [Figure 8] FIG. 2 is a diagram illustrating an example of the configuration of a drive unit. [Figure 9] 9 is a diagram illustrating a configuration example of a current adjusting circuit illustrated in FIG. 8. FIG. [Figure 10] FIG. 10 is a diagram illustrating another example of the configuration of the drive unit. [Figure 11] 6 is a flowchart illustrating an example of processing executed by the signal generating device in the first example. [Figure 12] 10 is a flowchart illustrating an example of processing executed by the signal generating device in the second example. [Figure 13] 10 is a flowchart illustrating an example of processing executed by the signal generating device in the third example. [Figure 14] 10 is a flowchart illustrating an example of processing executed by a signal generating device in the fourth example. [Figure 15] FIG. 10 is a diagram illustrating an example of the configuration of an adjustment system according to a second embodiment. [Figure 16] 10 is a diagram for explaining the state of the power conversion device when the power line, the measuring device, and the signal generating device are removed. FIG. [Figure 17] FIG. 2 is a diagram illustrating an example of a circuit configuration of a signal generating unit. [Figure 18] FIG. 10 is a diagram illustrating another example of the configuration of the power conversion device according to the second embodiment. [Figure 19] 10 is a diagram showing an example of the configuration of a power conversion device after a resistive element is attached to a land. FIG. [Figure 20]10 is a flowchart illustrating an example of processing executed by the adjustment system in the second embodiment. [Figure 21] FIG. 10 is a diagram illustrating an example of the configuration of an adjustment system in a modification of the first and second embodiments. [Figure 22] 10 is a timing diagram for explaining an example of the timing at which a drive capability signal is generated (updated). FIG. [Figure 23] FIG. 10 is a diagram illustrating another example of the configuration of the adjustment system according to the modified example of the first and second embodiments. [Figure 24] FIG. 11 shows an example of a configuration of an adjustment system according to a third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. The same or corresponding parts in the drawings will be denoted by the same reference numerals, and the description thereof will not be repeated. The embodiments and their modifications may be combined with each other as appropriate.

[0011] Embodiment 1 Fig. 1 is a diagram showing an example of the configuration of a power conversion system according to the first embodiment. Referring to Fig. 1, power conversion system 100 includes a power source 10 and an air conditioner 20 (outdoor unit). Air conditioner 20 is shown as an example of a heat pump device (air conditioning cooling and heating device), but may be replaced by other types of heat pump devices such as a refrigeration / freezer.

[0012] The power supply 10 supplies power to the air conditioner 20. The power supply 10 is an AC power supply (AC system), and is typically a commercial power supply.

[0013] The air conditioner 20 includes a power conversion device 1, a motor 7, and a compressor 9. The power conversion device 1 includes a substrate SB, a main conversion circuit 2, a main drive device 3, and a control device 4. The main conversion circuit 2, the main drive device 3, and the control device 4 are each provided on the substrate SB.

[0014] The main conversion circuit 2 is electrically connected between the power supply 10 and the motor 7. The main conversion circuit 2 converts power supplied from the power supply 10 into AC power and supplies the converted power to the motor 7. The main conversion circuit 2 includes a semiconductor module 201. The semiconductor module 201 includes a plurality of switching elements (for example, switching elements Q1 to Q6 in FIG. 2). Each of the switching elements Q1 to Q6 is a power semiconductor element such as a MOSFET, an IGBT, a MESFET (Metal-Semiconductor Field-Effect Transistor), or a bipolar transistor. The main driver 3 drives the semiconductor module 201. The controller 4 controls the main driver 3.

[0015] The motor 7 is a three-phase AC motor mounted on the air conditioner 20 and driven by power supplied from the main conversion circuit 2. The compressor 9 is an example of a load of the motor 7, and is configured to compress the refrigerant of the air conditioner 20 and supply the refrigerant to the refrigerant circuit.

[0016] 2 is a diagram showing an example of the configuration of the power conversion device 1. In this example, the power source 10 is a three-phase AC power source and supplies AC power to the main conversion circuit 2 via three AC input terminals Ta, Tb, and Tc. The motor 7 receives AC power from the main conversion circuit 2 via three AC output terminals Tu, Tv, and Tw. The main conversion circuit 2 includes a rectifier circuit 21, a DC power line PL (a high-potential side DC bus), a DC power line NL (a low-potential side DC bus), an inverter circuit 22, a reactor L1, and a capacitor C.

[0017] The rectifier circuit 21 is, for example, a full-wave rectifier circuit and includes six diodes 211 to 216. The diode 211 has a cathode connected to the DC power line PL and an anode connected to the AC input terminal Ta. The diode 212 has a cathode connected to the AC input terminal Ta and an anode connected to the DC power line NL. The diode 213 has a cathode connected to the DC power line PL and an anode connected to the AC input terminal Tb. The diode 214 has a cathode connected to the AC input terminal Tb and an anode connected to the DC power line NL. The diode 215 has a cathode connected to the DC power line PL and an anode connected to the AC input terminal Tc. The diode 216 has a cathode connected to the AC input terminal Tc and an anode connected to the DC power line NL.

[0018] The inverter circuit 22 is, for example, a two-level three-phase full-bridge circuit and includes switching elements Q1 to Q6 and freewheel diodes D1 to D6. The freewheel diodes D1 to D6 are connected in anti-parallel to the switching elements Q1 to Q6, respectively. The switching elements Q1 and Q2 are connected in series to form a U-phase arm 22U of the full-bridge circuit. The switching element Q2 operates in a complementary manner with the switching element Q1. The switching elements Q3 and Q4 are connected in series to form a V-phase arm 22V of the full-bridge circuit. The switching element Q4 operates in a complementary manner with the switching element Q3. The switching elements Q5 and Q6 are connected in series to form a W-phase arm 22W of the full-bridge circuit. The switching element Q6 operates in a complementary manner with the switching element Q5. Each of the switching elements Q1 to Q6 is connected between the DC power line PL and the DC power line NL.

[0019] Each of the switching elements Q1 and Q2 is connected to the U phase of the motor 7. Each of the switching elements Q3 and Q4 is connected to the V phase of the motor 7. Each of the switching elements Q5 and Q6 is connected to the W phase of the motor 7. In this manner, each switching element is connected to a corresponding phase of the motor 7. Each switching element is connected between the DC power line PL and the DC power line NL. Each phase arm is connected between the DC power line PL and the DC power line NL. The U phase arm, the V phase arm, and the W phase arm are connected to the AC output terminals Tu, Tv, and Tw, respectively.

[0020] The main driving device 3 includes driving circuits 31 to 36. The driving circuits 31 to 36 drive the switching elements Q1 to Q6, respectively. The configuration of each driving circuit 31 to 36 will be described with reference to FIG. 4 and subsequent figures. The control device 4 generates a driving signal Vinj (j=1 to 6) for each of the driving circuits 31 to 36. The driving signal Vinj is generated, for example, by PWM (Pulse Width Modulation) control based on a comparison between a triangular wave carrier signal and a voltage command value.

[0021] Reactor L1 is provided on DC power line PL between rectifier circuit 21 and inverter circuit 22. Capacitor C is connected between DC power line PL and DC power line NL.

[0022] 3 is a diagram showing an example of the hardware configuration of the control device 4. The control device 4 includes a processor 41, a memory 42, a storage device 43, an input device 44a, and a display device 44b.

[0023] The processor 41 is an arithmetic processing device such as a CPU (Central Processing Unit) or an MPU (Micro Processing Unit) and executes various types of arithmetic processing. The processor 41 may be replaced by a dedicated processing circuit such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array). The memory 42 includes a ROM (Read Only Memory) 42a and a RAM (Random Access Memory) 42b. The ROM stores programs including computer-readable codes executed by the processor 41. The RAM 42b functions as a working memory. The storage device 43 stores various types of information used for controlling the power conversion device 1.

[0024] The input device 44a is an operation button or the like and receives operations by the user. This operation includes an operation for temporarily stopping the power conversion device 1. The display device 44b is a monitor or the like and displays the progress and results of the calculation processing by the processor 41 to the user.

[0025] FIG. 4 is a diagram showing the basic configuration of switching element Q, main driving device 3, and control device 4. Each of driving circuits 31 to 36 shown in FIG. 4 operates in the same way for a corresponding switching element among switching elements Q1 to Q6. Therefore, the following drawings only show switching element Q and driving circuit 30 as a representative. Switching element Q is one of six switching elements Q1 to Q6. The following mainly describes an example in which switching element Q is a MOSFET. Switching element Q includes a drain D, a source S, and a gate G (control electrode). Driving circuit 30 is a driving circuit among driving circuits 31 to 36 corresponding to switching element Q and is configured to drive switching element Q.

[0026] The control device 4 is connected to the power supply node PNA and includes a signal generating unit 45. The power supply node PNA constitutes the power supply for the power conversion device 1. The voltage at the power supply node PNA is also referred to as voltage VccA. The signal generating unit 45 generates a drive signal Vin. The drive signal Vin is a signal for controlling the switching (on / off) timing of the switching element Q. The signal generating unit 45 may be a dedicated processing circuit (not shown) such as an ASIC or FPGA, or may be realized as a function performed by the processor 41 executing a program in the ROM 42a.

[0027] The drive circuit 30 is connected to a power supply node PN and ground GND. The potential of ground GND is used as a reference potential of the drive circuit 30. The voltage of the power supply node PN is also referred to as a power supply voltage Vcc. The reference potential and power supply voltage Vcc of the drive circuits 31, 33, and 35 (upper arm drive circuits) are different from the reference potential and power supply voltage Vcc of the drive circuits 32, 34, and 36 (lower arm drive circuits).

[0028] The drive circuit 30 drives the switching element Q in accordance with the drive signal Vin and the adjustment signal Vref. The adjustment signal Vref is a signal for adjusting the switching speed of the switching element Q. The adjustment signal Vref will be described in detail later. The drive circuit 30 includes terminals T1 to T3, an adjustment unit 302, and a drive unit 301.

[0029] Terminal T1 is an input terminal configured to receive drive signal Vin from control device 4. As described above, the reference potential and power supply voltage Vcc of the upper arm drive circuit may differ from the reference potential and power supply voltage Vcc of the lower arm drive circuit, and therefore an interface (level shift circuit, isolator, etc.) (not shown) is provided between terminal T1 of each of drive circuits 31, 33, 35 and control device 4. Terminal T2 is an input terminal configured to receive adjustment signal Vref from a signal generating device 75 (described later) external to power conversion device 1 via power line LN.

[0030] The adjustment unit 302 generates a drive capability signal Vcap in accordance with the adjustment signal Vref and outputs the drive capability signal Vcap to the drive unit 301. The drive capability signal Vcap is a signal for determining an adjustment value for the drive capability (switching speed) of the switching element Q. Specifically, this adjustment value is determined by the signal value (voltage value in this example) of the drive capability signal Vcap. The adjustment unit 302 is, for example, a dedicated processing circuit such as an ASIC or FPGA.

[0031] In the embodiment, the switching element Q is driven by the driving unit 301 at a switching speed determined in response to the output of the driving capability signal Vcap. This makes it possible to adjust (change) the switching speed at an appropriate timing using the driving capability signal Vcap.

[0032] FIG. 5 is a diagram showing an example of the relationship between the voltage value of the adjustment signal Vref and the voltage value of the drive capability signal Vcap. Referring to FIG. 5, in this example, for ease of understanding, it is assumed that the voltage value of the drive capability signal Vcap is the same as the voltage value of the adjustment signal Vref. The voltage value of the adjustment signal Vref is a value for controlling the switching speed of the switching element Q. The switching speed increases as this voltage value increases. Basically, this voltage value is within a predetermined range (for example, a range of 0V to 5V). An example in which the drive capability signal Vcap is different from the adjustment signal Vref will be described in a modified example below.

[0033] Referring again to FIG. 4, the measuring device 70 is provided outside the power conversion device 1 and measures a physical quantity of the power conversion device 1. This physical quantity is also referred to as a "physical quantity of interest." The physical quantity of interest is, for example, the switching time of the switching element Q. In this case, the measuring device 70 is, for example, an oscilloscope. The switching time is a time used as an index representing the length of time required for switching, and may be, for example, any of the turn-on time, turn-off time, rise time, and fall time. The switching time becomes shorter as the switching speed increases, and longer as the switching speed decreases.

[0034] The target physical quantity may be the leakage current of the power conversion device 1, the power conversion efficiency (output power / input power) or heat generation of the power conversion device 1, the electromagnetic noise of the power conversion device 1 (electromagnetic noise from the switching element Q), or the volume of the power conversion device 1 (volume of operating noise). In this case, the measuring device 70 is, for example, a clamp meter, a power analyzer, a calorimeter, a spectrum analyzer, or a volume meter (sound level meter). Hereinafter, electromagnetic noise will also be simply referred to as "noise." The leakage current is an AC current that flows from the power conversion device 1 to a ground node (not shown) through its stray capacitance. The leakage current decreases as the switching speed decreases. The higher the switching speed, the higher the conversion efficiency and the lower the heat generation. The noise decreases as the switching speed decreases. The volume of the power conversion device 1 decreases as the switching speed decreases.

[0035] The signal generating device (adjusting device) 75 is provided outside the power conversion device 1 and configured to communicate with the measuring device 70 via wired or wireless communication. The signal generating device 75 includes a dedicated processing circuit such as an ASIC or FPGA. The signal generating device 75 generates an adjusted signal Vref. The signal generating device 75 is configured to generate the adjusted signal Vref so that its voltage value falls within a reference range (in this example, within a range of 0 V to 5 V). In the following explanation, the case where the voltage value is Vk (= k [V]) (k = 0, 1, 2, 3, 4, 5) will be mainly explained. The function of the signal generating device 75 will be explained in detail later. The power conversion device 1, the measuring device 70, and the signal generating device 75 are also referred to as an "adjustment system 80."

[0036] The driver 301 drives the switching element Q by generating a gate signal Sg in accordance with the drive signal Vin and the drive capability signal Vcap. The gate signal Sg is provided to the gate G of the switching element Q via terminal T3. This drives the switching element Q in accordance with the gate signal Sg. The driver 301 adjusts the drive signal Vin in response to the drive capability signal Vcap, and outputs the adjusted drive signal Vin to the gate G as the gate signal Sg. This changes the waveform of the gate signal Sg in accordance with the drive capability signal Vcap, and the switching element Q is driven at a switching speed determined in accordance with the adjustment signal Vref (drive capability signal Vcap).

[0037] Below, we will explain three typical configuration examples of the driving unit 301. However, the configuration of the driving unit 301 is not limited to the following configurations as long as the switching speed of the switching element Q can be adjusted.

[0038] 6 is a diagram showing an example of the configuration of a drive unit. Drive unit 301A is configured to change the gate resistance included in drive unit 301. Drive unit 301A includes a control circuit 51 and a resistance adjustment circuit 52.

[0039] The resistance adjustment circuit 52 includes, for example, a plurality of series circuits. Each series circuit includes a resistance element 521 and a switch 522 connected in series. The switch 522 is controlled to be turned on and off in response to a control signal from the control circuit 51. The control circuit 51 drives the resistance adjustment circuit 52 based on a drive signal Vin and a drive capability signal Vcap. More specifically, the control circuit 51 determines the drive timing of the resistance adjustment circuit 52 based on the drive signal Vin. The control circuit 51 selects, from the plurality of resistance elements 521 included in the resistance adjustment circuit 52, a resistance element to be controlled (which resistance element to connect and which resistance element to disconnect) based on the drive capability signal Vcap. The control circuit 51 can adjust the gate resistance of the switching element Q by switching on and off each switch 522.

[0040] Fig. 7 is a diagram showing an example of the configuration of the resistance adjusting circuit 52 shown in Fig. 6. The resistance adjusting circuit 52 includes a plurality of (eight in this example) P-channel MOSFETs 610 to 617 connected in parallel with each other, and a plurality of (eight in this example) N-channel MOSFETs 620 to 627 connected in parallel with each other.

[0041] The eight P-channel MOSFETs 610-617 have different gate widths (more specifically, gate widths that double from Wp to 128Wp). The same applies to the eight N-channel MOSFETs 620-627. The P-channel MOSFETs 610-617 and N-channel MOSFETs 620-627 are each controlled to turn on and off in response to signals (Hp[0]-Hp[7], Hn[0]-Hn[7]) from the control circuit 51. The common source of the P-channel MOSFETs 610-617 and the common drain of the N-channel MOSFETs 620-627 are connected to the gate G of the switching element Q. By employing this circuit configuration, the gate resistance of the switching element Q can be adjusted in stages (256 stages in this example). Although the switching element Q is a MOSFET in this example, it may also be an IGBT.

[0042] 8 is a diagram showing an example of the configuration of the drive unit. The drive unit 301B is configured to change the base current of the switching element Q. The drive unit 301B includes a control circuit 53 and a current adjustment circuit .

[0043] The current adjustment circuit 54 includes a switch 541 connected to the base of the switching element Q, and an operational amplifier 542. The operational amplifier 542 changes the current flowing through the switch 541 (the base current of the switching element Q) so as to follow the drive capability signal Vcap input from the adjustment unit 302. The control circuit 53 controls the on / off of the current flowing through the switch 541 by switching the switch 541 in accordance with the drive signal Vin.

[0044] Fig. 9 is a diagram showing an example of the configuration of the current adjustment circuit 54 shown in Fig. 8. The current adjustment circuit 54 includes a current mirror circuit 63, an error amplifier circuit 64, and a switch 65.

[0045] The current mirror circuit 63 includes a pair of transistors (P-channel MOSFETs in this example) 631 and 632 with a transistor size ratio of 1:x (for example, x=100). The gates of the transistors 631 and 632 are connected to each other. The sources of the transistors 631 and 632 are connected in parallel to a power supply voltage Vcc. The drain of the transistor 631 is connected to the common gate of the transistors 631 and 632. The current mirror circuit 63 passes a current Ib, which is proportional to a current Ia flowing through the transistor 631 on the input side, through the transistor 632 on the output side.

[0046] The error amplifier circuit 64 includes a transistor (in this example, an N-channel MOSFET) 641 for varying the magnitude of the current Ia flowing through the input-side transistor 631, a resistor 642 for generating a voltage Va corresponding to the current Ia, and an operational amplifier 643. The drain and source of the transistor 641 and the resistor 642 are connected in series between the drain of the transistor 631 of the current mirror circuit 63 and ground GND. The non-inverting input terminal of the operational amplifier 643 is connected to a node that receives a drive capability signal Vcap from the adjustment unit 302. The inverting input terminal of the operational amplifier 643 is connected to the source of the transistor 641. The error amplifier circuit 64 detects the current Ia flowing through the input side of the current mirror circuit 63 and generates a corresponding voltage Va. The error amplifier circuit 64 varies the current Ia so that the voltage Va follows the drive capability signal Vcap. By employing this circuit configuration, the base current of the switching element Q (the current Ib on the output side of the current mirror circuit 63) can be adjusted in accordance with the drive capability signal Vcap.

[0047] 10 is a diagram showing another example of the configuration of the driver. Driver 301C is configured to change the gate voltage applied to driver 301. Driver 301C includes a voltage adjustment circuit 55 and a driver circuit 56. Driver circuit 56 includes, for example, an NPN bipolar transistor 561 and a PNP bipolar transistor 562 connected in series between a power supply voltage Vcc and ground GND. The gates of bipolar transistors 561 and 562 are connected to a common node.

[0048] The voltage adjustment circuit 55 includes a voltage amplifier 551 (for example, an operational amplifier circuit). The voltage adjustment circuit 55 outputs a drive signal Vin amplified by the voltage amplifier 551 to the gates of bipolar transistors 561 and 562. The amplification factor of the voltage amplifier 551 is adjusted by a drive capability signal Vcap. This makes it possible to adjust the gate voltage when switching on and off the bipolar transistors 561 and 562 of the drive circuit 56. Note that although the switching element Q is a MOSFET in this example, it may also be an IGBT.

[0049] The higher the switching speed of each switching element, the smaller the switching loss, while the lower the switching speed, the smaller the electromagnetic noise (switching noise) from the switching element. Electromagnetic noise includes radiated noise (e.g., 30 MHz to 1 GHz) and conducted noise (e.g., 150 MHz to 1 GHz). The allowable amount of radiated noise (allowable amount of radiated noise) and the allowable amount of conducted noise (allowable amount of conducted noise) are each determined by a predetermined noise standard. By reducing the electromagnetic noise, it is preferable to keep the amount of radiated noise and the amount of conducted noise below their allowable amounts. Adjusting the switching speed of each switching element in the power conversion device 1 is important for reducing loss or noise in the power conversion device 1 when the motor 7 is driven.

[0050] The magnitude of noise, loss, etc. of the power conversion device 1 may deviate from a desired range (value) due to component variations (individual variations) during mass production. When individual variations are large, the power conversion device 1 is more likely to not meet quality standards in terms of noise, loss, etc. (noise, loss, etc. are outside the desired range). As a result, the yield on the production line may decrease. The noise, loss, etc. of the power conversion device 1 may deviate from the desired range due to changes in the installation environment of the electrical equipment (in this example, air conditioner 20) in which the power conversion device 1 is installed, aging deterioration of the parts of the power conversion device 1, etc. After manufacturing (assembling) the power conversion device 1, replacing the parts of the power conversion device 1 or reproducing a different power conversion device so that the magnitude of loss, noise, etc. is within the desired range requires a lot of effort and increases costs.

[0051] 4 again, adjustment system 80 according to the first embodiment has a configuration for dealing with such a problem. Specifically, signal generating device 75 of adjustment system 80 acquires measurement information MI indicating the measurement result of the target physical quantity from measurement device 70, and generates adjustment signal Vref in accordance with the measurement information MI.

[0052] With this configuration, an adjustment signal Vref is generated based on the measurement result of the target physical quantity of the power conversion device 1. The adjustment signal Vref is supplied to the drive circuit 30 and used by the drive circuit 30 to drive the switching element Q. This allows the switching speed to be appropriately adjusted by inputting the adjustment signal Vref without replacing or reproducing parts of the power conversion device 1. As a result, even if the power conversion device 1 does not meet quality standards in terms of noise or loss magnitude after its manufacture (assembly), the noise or loss magnitude can be easily adjusted (optimized) in a subsequent inspection process. Therefore, the quality of the power conversion device 1 can be assured using a simple method. Adjusting the switching speed using the signal generator 75 in this way is effective, for example, in an inspection process after manufacture of the power conversion device 1. Note that adjusting the switching speed in this manner is also effective in processes other than the inspection process. This point will be described later.

[0053] Hereinafter, first to fifth examples will be described regarding how the signal generating device 75 generates the adjustment signal Vref according to the measurement information MI.

[0054] In a first example, the target physical quantity is a switching time, and the signal generator 75 generates the adjustment signal Vref (for example, by feedback control) so that the switching time approaches a reference value. For example, if the switching time is longer than the reference value, the signal generator 75 generates the adjustment signal Vref so that the switching speed (voltage value) increases. If the switching time is shorter than the reference value, the signal generator 75 generates the adjustment signal Vref so that the switching speed decreases. The reference value is a range in this example, but may also be a value. Information indicating the reference value is stored in the memory of the signal generator 75.

[0055] This configuration makes it possible to prevent the switching time from becoming too short or too long compared to the reference time, thereby preventing excessive increases in loss or noise in the power conversion device 1 and optimizing the balance between loss and noise.

[0056] 11 is a flowchart showing an example of processing executed by the signal generating device 75 in the first example. This flowchart is executed at predetermined time intervals.

[0057] 11, the signal generating device 75 acquires measurement information MI including a measurement value of the switching time from the measuring device 70 (S105). The signal generating device 75 determines whether the switching time is outside its reference range according to the measurement information MI (S110). If the switching time is within the reference range (NO in S110), the process proceeds to RETURN. If the switching time is outside the reference range (YES in S110), the signal generating device 75 determines whether the switching time is longer than the upper limit of the reference range (S112).

[0058] If the switching time is longer than the upper limit of the reference range (YES in S112), the signal generating device 75 generates the adjustment signal Vref so that the switching speed (voltage value) increases (S115).

[0059] If the switching time is not longer than the upper limit of the reference range, i.e., if the switching time is shorter than the lower limit of the reference range (NO in S112), the signal generating device 75 generates the adjustment signal Vref so as to decrease the switching speed (S120). After S115 or S120, the process returns to RETURN. As a result, the switching speed is adjusted (changed) until the switching time falls within the reference range (NO in S110).

[0060] In a second example, the target physical quantity is the leakage current of the power conversion device 1, and the signal generating device 75 generates the adjustment signal Vref so that the switching speed is reduced when the leakage current is greater than a reference value. The reference value is a range in this example, but may be a value. Information indicating the reference value is stored in the memory of the signal generating device 75.

[0061] This configuration reduces the leakage current due to a decrease in switching speed, thereby preventing the leakage current from increasing excessively.

[0062] 12 is a flowchart showing an example of processing executed by the signal generating device 75 in the second example. This flowchart is executed at predetermined time intervals.

[0063] 12, the signal generating device 75 acquires measurement information MI including a measurement value of the leakage current from the measuring device 70 (S205). The signal generating device 75 determines whether the leakage current is greater than the upper limit of its reference range according to the measurement information MI (S210).

[0064] If the leakage current is smaller than the upper limit of the reference range, for example, if it is within the reference range (NO in S210), the process proceeds to RETURN. If the leakage current is larger than the upper limit of the reference range (YES in S210), the signal generating device 75 generates the adjustment signal Vref so that the switching speed is reduced (S215). Thereafter, the process proceeds to RETURN. As a result, the switching speed is adjusted (reduced) until the leakage current is within the reference range (NO in S210).

[0065] In a third example, the target physical quantity is the power conversion efficiency or heat generation amount of the power conversion device 1, and the signal generating device 75 generates the adjustment signal Vref so that the switching speed increases when the power conversion efficiency is lower than the reference value or when the heat generation amount is higher than the reference value. Each of these reference values ​​is a range in this example, but may also be a value. Information indicating these reference values ​​is stored in the memory of the signal generating device 75.

[0066] With the above configuration, the power conversion efficiency increases and the amount of heat generated decreases due to the increased switching speed, thereby preventing an excessive decrease in power conversion efficiency and overheating of the power conversion device 1.

[0067] 13 is a flowchart showing an example of processing executed by the signal generating device 75 in the third example. This flowchart is executed at predetermined time intervals. In this example, the target physical quantity is power conversion efficiency.

[0068] 13, the signal generating device 75 acquires measurement information MI including a measurement value of the power conversion efficiency from the measuring device 70 (S305). The signal generating device 75 determines whether the power conversion efficiency is lower than the lower limit of its reference range according to the measurement information MI (S310).

[0069] If the power conversion efficiency is equal to or greater than the lower limit of the reference range, for example, if it is within the reference range (NO in S310), the process proceeds to RETURN. If the power conversion efficiency is lower than the lower limit of the reference range (YES in S310), the signal generating device 75 generates the adjustment signal Vref so that the switching speed increases (S315). Thereafter, the process proceeds to RETURN. As a result, the switching speed is adjusted (increased) until the power conversion efficiency falls within the reference range (NO in S310).

[0070] In a fourth example, the target physical quantity is noise (more specifically, the amount of noise in a certain frequency range) of the power conversion device 1 (switching element Q), and the signal generating device 75 generates the adjustment signal Vref so as to reduce the switching speed when the noise is greater than a reference value. The noise may be either radiated noise or conducted noise. The noise reference is a range in this example, but may also be a value. This value is, for example, the value of the allowable amount of radiated noise or the allowable amount of conducted noise described above. Information indicating the noise reference is stored in the memory of the signal generating device 75.

[0071] The above configuration reduces noise due to a slower switching speed, thereby preventing excessive noise increases and making it easier to ensure compliance with electromagnetic noise standards.

[0072] 14 is a flowchart showing an example of processing executed by the signal generating device 75 in the fourth example. This flowchart is executed at predetermined time intervals.

[0073] 14, the signal generating device 75 acquires measurement information MI including a noise measurement value from the measuring device 70 (S405). The signal generating device 75 determines whether the noise is greater than the upper limit of its reference range according to the measurement information MI (S410).

[0074] If the noise is equal to or less than the upper limit of the reference range, for example, within the reference range (NO in S410), the process proceeds to RETURN. If the noise is greater than the upper limit of the reference range (YES in S410), the signal generating device 75 generates the adjustment signal Vref so that the switching speed is reduced (S415). Thereafter, the process proceeds to RETURN. As a result, the switching speed is adjusted (reduced) until the noise is within the reference range (NO in S410).

[0075] In a fifth example, the target physical quantity is the volume of the power conversion device 1 (the volume of operating noise generated by this device), and the signal generating device 75 generates the adjustment signal Vref so that the switching speed decreases when the volume is greater than a reference value. The reference value is a range in this example, but may also be a value. Information indicating the reference value is stored in the memory of the signal generating device 75.

[0076] The above configuration reduces the operating noise caused by a decrease in the switching speed, thereby preventing an excessive increase in operating noise. As a result, the quietness of the power conversion device 1 can be ensured.

[0077] The procedure of the process executed by the signal generating device 75 in the fifth example is expressed by the flowchart in FIG. 14, where "noise" is replaced with "operating sound."

[0078] As described above, according to the first embodiment, the adjustment signal Vref is input from the signal generating device 75 to the power conversion device 1, and the switching speed is appropriately adjusted. As a result, even if the power conversion device 1 does not satisfy the quality standard, the magnitude of noise or loss can be easily adjusted in a subsequent inspection process. Therefore, the quality of the power conversion device 1 can be guaranteed by a simple method. As a result, the yield in the manufacturing line can be improved.

[0079] Adjusting the switching speed using the signal generating device 75 may be performed after the installation of the air conditioner 20 on which the power conversion device 1 is mounted. For example, if loss reduction (overheat prevention) is required at the installation location of the air conditioner 20, the signal generating device 75 increases the voltage value of the adjustment signal Vref. This increases the switching speed, making it possible to easily meet such a requirement. Alternatively, if noise reduction is required at the installation location of the air conditioner 20, the signal generating device 75 decreases the voltage value of the adjustment signal Vref. This decreases the switching speed, making it possible to easily meet such a requirement.

[0080] Adjusting the switching speed using the signal generating device 75 is also effective during maintenance of the power conversion device 1. This makes it easy to deal with increases in loss or noise in the power conversion device 1 due to aging of the components of the power conversion device 1.

[0081] In order to deal with individual variations in the power conversion device 1, derating may be performed for noise, loss (heat generation), surge voltage, etc. Even in such cases, the derating can be reduced by adjusting the switching speed using the signal generating device 75. As a result, the performance of the various components of the power conversion device 1 can be fully exhibited.

[0082] Embodiment 2 FIG. 15 is a diagram illustrating an example of the configuration of an adjustment system according to the second embodiment. Referring to FIG. 15, an adjustment system 80A differs from the adjustment system 80 (FIG. 4) according to the first embodiment in that the adjustment system 80A includes a drive circuit 30A instead of the drive circuit 30, and the power conversion device 1 further includes a signal generating unit 46 and a voltage sensor 47. The adjustment system 80A also differs from the adjustment system 80 in that the storage device 43 of the power conversion device 1 stores voltage value information (signal value information) 43c. In other respects, the adjustment system 80A is basically the same as the adjustment system 80 unless otherwise noted. The drive circuit 30A differs from the drive circuit 30 in that it further includes a terminal T2A.

[0083] The signal generating unit 46 generates a signal equivalent to the adjustment signal Vref when the input of the adjustment signal Vref from the signal generating device 75 to the power conversion device 1 is stopped (for example, when the power line LN, the measuring device 70, and the signal generating device 75 are removed).

[0084] Voltage sensor 47 detects the voltage value of adjustment signal Vref transmitted from signal generator 75 via terminals T2 and T2A. Voltage value information 43c indicates the voltage value detected by voltage sensor 47. Voltage value information 43c is updated and read out by control device 4 as appropriate in accordance with the value detected by voltage sensor 47.

[0085] FIG. 16 is a diagram for explaining the state of the power conversion device 1 when the power line LN, the measuring device 70, and the signal generating device 75 are removed. Referring to FIG. 16, the signal generating unit 46 generates a signal VrefA in accordance with the voltage value information 43c. In this example, the signal VrefA is a signal corresponding to the adjustment signal Vref (FIG. 15), and the voltage value of the signal VrefA is equal to the voltage value indicated by the voltage value information 43c. In other words, the signal VrefA is a signal that reproduces the adjustment signal Vref (hereinafter also referred to as a "reproduced signal"). The signal VrefA is provided to the adjusting unit 302 via a terminal T2A. The signal generating unit 46 corresponds to an example of a "reproduced signal generating unit" in the present disclosure.

[0086] The adjustment unit 302 generates the drive capability signal Vcap in accordance with the voltage value information 43c (in accordance with the signal VrefA instead of the adjustment signal Vref). As a result, the switching speed is adjusted in the same manner as when the adjustment signal Vref is input from the signal generating device 75 to the power conversion device 1. Therefore, even if the input of the adjustment signal Vref from the signal generating device 75 to the power conversion device 1 is stopped, the switching element Q can continue to be driven at an appropriate switching speed.

[0087] 17 is a diagram showing an example of a circuit configuration of signal generating unit 46. Referring to FIG.

[0088] The voltage divider circuit 48 divides the voltage VccA and generates, as an output signal, a signal VrefA having a divided voltage value equal to the value of the divided voltage DV of the voltage VccA. The voltage divider circuit 48 includes relays RLa1 to RLa5 and resistors Ra1 to Ra4 and Rb. The relays RLa1 to RLa4 are connected to the resistors Ra1 to Ra4, respectively.

[0089] The voltage dividing circuit control unit 49 controls the voltage dividing circuit 48. Specifically, the voltage dividing circuit control unit 49 switches the relays RLa1 to RLa5 on and off according to the detection value of the voltage sensor 47. For example, the voltage dividing circuit control unit 49 controls all of the relays RLa1 to RLa5 to the off state, or controls only one of these relays to the on state.

[0090] When the adjustment signal Vref is input from the signal generating device 75 to the terminal T2, the voltage dividing circuit control unit 49 turns off all relays. As a result, the signal VrefA is not generated. In other words, the voltage value of the signal VrefA is V0 (=0V). The voltage dividing circuit control unit 49 can determine whether the adjustment signal Vref is being input based on the detection value of the voltage sensor 47.

[0091] When the input of the adjustment signal Vref from the signal generating device 75 to the terminal T2 is stopped (when the detected value of the voltage sensor 47 drops to zero), the voltage divider circuit control unit 49 controls only one of the relays RLa1 to RLa4 to the ON state. As a result, a current flows from the power supply node PNA to the ground through the resistor connected to that relay and the resistor Rb. As a result, a signal VrefA having the value of the divided voltage DV as its divided voltage value is generated and input from the signal generating unit 46 to the adjustment unit 302 via the terminal T2A.

[0092] When the detected value of the voltage sensor 47 drops to zero, the voltage divider circuit control unit 49 reads the voltage value indicated by the voltage value information 43c immediately before the detected value dropped to zero and determines which relay to turn on based on this voltage value. For example, when the voltage value information 43c indicates that the voltage value of the adjustment signal Vref was Vk (1≦k≦5), the voltage divider circuit control unit 49 controls the relay RLak to be in the on state (DV=Vk). In other words, when the input of the adjustment signal Vref is stopped, the voltage divider circuit control unit 49 controls the voltage divider circuit 48 to supply the drive circuit 30 with a signal VrefA having the divided voltage value indicated by the voltage value information 43c via the terminal T2A.

[0093] The adjusting unit 302 generates the driving capability signal Vcap in accordance with the signal VrefA (the voltage value indicated by the voltage value information 43c) supplied from the voltage dividing circuit .

[0094] The signal generating unit 46 may be a dedicated processing circuit (not shown), such as an ASIC or FPGA, or may be implemented as a function performed by the processor 41 executing a program stored in the ROM 42a. Even in such a case, when the signal generating unit 46 detects that the detected value of the voltage sensor 47 has dropped to zero, it reads the voltage value indicated by the voltage value information 43c and automatically generates the signal VrefA according to this voltage value. This causes the adjusting unit 302 to generate the drive capability signal Vcap. Alternatively, the driving circuit 30A may further include a storage unit (not shown) that stores the same voltage value information as the voltage value information 43c. When the detected value of the voltage sensor 47 drops to zero, the adjusting unit 302 reads the voltage value information stored in the storage unit immediately before the detected value dropped to zero and generates the drive capability signal Vcap according to this voltage value information instead of the adjustment signal Vref.

[0095] Fig. 18 is a diagram illustrating another configuration example of the power conversion device according to the embodiment 2. Referring to Fig. 18, the power conversion device 1 may have a land LND1, a land LND2, and a wiring pattern PTN on a substrate SB.

[0096] Each of the lands LND1 and LND2 is a bonding electrode that enables electrical connection with a resistive element, and is formed of, for example, copper foil. Each of the lands LND1 and LND2 is formed on the substrate SB outside the control device 4 (voltage divider circuit 48) in the power conversion device 1. The land LND1 is connected to the power supply node PNA and is configured to allow attachment of the resistive element 50_1. The land LND2 is connected to the power supply node PNA via the land LND1 and is configured to allow attachment of the resistive element 50_2. The land LND2 is also connected to the ground GND.

[0097] The wiring pattern PTN interconnects the lands LND1 and LND2 and is provided between the lands LND1 and LND2 and the drive circuit 30A (terminal T2). The wiring pattern PTN is formed of, for example, copper foil. When the resistive elements 50_1 and 50_2 are attached to the lands LND1 and LND2, respectively, the wiring pattern PTN functions as an electrical path that electrically connects the power supply node PNA to the drive circuit 30A.

[0098] FIG. 19 is a diagram illustrating a configuration example of the power conversion device 1 after the resistive elements 50_1 and 50_2 are attached to the lands LND1 and LND2. Referring to FIG. 19, the resistive elements 50_1 and 50_2 generate a signal VrefB (voltage-divided signal) having a divided voltage value of the voltage VccA. The divided voltage value is determined according to the ratio (resistance ratio) between the resistance value of the resistive element 50_1 and the resistance value of the resistive element 50_2. The wiring pattern PTN transmits the signal VrefB to the terminal T2. Thereafter, the signal VrefB is input to the adjustment unit 302 and used for adjusting the switching speed in the same manner as the signal VrefA.

[0099] For example, once a desired switching speed is achieved using the adjustment signal Vref, the power conversion device 1 is temporarily stopped by a user. Then, the signal generating device 75 is removed from the power conversion device 1 (the input of the adjustment signal Vref is stopped). Then, for example, the user selects resistor elements 50_1 and 50_2 capable of generating a signal VrefB having the same divided voltage value as the voltage value of the adjustment signal Vref immediately before the power conversion device 1 was stopped. The selected resistor elements 50_1 and 50_2 are attached to lands LND1 and LND2, respectively, by, for example, soldering. This allows the signal VrefB to be used to adjust the switching speed to a desired speed even after the input of the adjustment signal Vref is stopped. For example, during development of the power conversion device 1, the switching speed is adjusted using the adjustment signal Vref from the signal generating device 75, and an optimal resistance ratio is determined based on the results of the adjustment. The resistor elements 50_1 and 50_2 are then attached during mass production of the power conversion device 1. Like signal VrefA, signal VrefB is an example of the aforementioned "reproduced signal."

[0100] When the switching speed is adjusted using the signal VrefB in this manner, the control device 4 does not necessarily need to include the signal generating unit 46. As a result, the reproduction signal can be generated with a simpler configuration, thereby reducing costs. The resistive elements 50_1 and 50_2, the lands LND1 and LND2, and the wiring pattern PTN correspond to an example of a "reproduction signal generating unit" in the present disclosure.

[0101] Note that when the resistive elements 50_1 and 50_2 generate the signal VrefB, the control device 4 does not need to generate the signal VrefA to be input to the terminal T2A. Therefore, in this case, it is preferable that the control device 4 executes processing to open the signal line from itself to the terminal T2A. On the other hand, when the control device 4 includes the voltage value of the signal VrefB (the detected value of the voltage sensor 47) in the read voltage value information 43c, the control device 4 may maintain the connection between the control device 4 and the terminal T2A without opening the signal line so that the signal VrefB is input to the control device 4 through the terminals T2 and T2A.

[0102] 20 is a flowchart illustrating an example of processing executed by the adjustment system 80A in the embodiment 2. This flowchart illustrates the steps of a method for driving the switching element Q, which starts when the signal generating device 75 is attached to the power conversion device 1.

[0103] Referring to FIG. 20, the signal generating unit 45 of the power conversion device 1 generates the drive signal Vin (S105).

[0104] The signal generating device 75 generates the adjustment signal Vref in accordance with the measurement result of the target physical quantity (S210). The adjustment signal Vref continues to be generated and input to the power conversion device 1 as long as the signal generating device 75 is attached to the power conversion device 1 (NO in S225). The generation of the adjustment signal Vref stops when the signal generating device 75 is detached from the power conversion device 1 (YES in S225).

[0105] Terminal T2 of power conversion device 1 receives adjustment signal Vref from outside power conversion device 1 (specifically, signal generating device 75) (S115). Drive circuit 30 of power conversion device 1 drives switching element Q in accordance with drive signal Vin and adjustment signal Vref (S120). Switching element Q is driven in a state where signal generating device 75 is connected to power conversion device 1.

[0106] If the input of the adjustment signal Vref from the signal generator 75 to the terminal T2 continues (NO in S125), the process returns to S105.

[0107] When the input of the adjustment signal Vref is stopped (YES in S125), the power conversion device 1 generates a reproduction signal (S130). This reproduction signal may be either the signal VrefA or the signal VrefB. For example, when the reproduction signal is the signal VrefA, the signal VrefA is automatically generated by the signal generating unit 46. When the reproduction signal is the signal VrefB, the user selects the resistive elements 50_1 and 50_2 having a resistance ratio for reproducing the optimum switching speed, and then the resistive elements 50_1 and 50_2 are attached to the lands LND1 and LND2 by soldering or the like to generate the signal VrefB. The reproduction signal is generated in a state where the signal generating device 75 is detached from the power conversion device 1 (a state where the generation of the adjustment signal Vref is stopped). The drive circuit 30 drives the switching element Q in accordance with the drive signal Vin and the reproduction signal (S135).

[0108] As described above, according to the second embodiment, the drive circuit 30 drives the switching element Q in accordance with the drive signal Vin and the adjustment signal Vref or the reproduced signal (for example, the signal VrefA or the signal VrefB). As a result, even if the input of the adjustment signal Vref from the signal generating device 75 to the power conversion device 1 is stopped, the switching element Q can continue to be driven at an appropriate switching speed using the reproduced signal. Furthermore, since the power supply node PNA (voltage VccA) can be used to adjust the switching speed, component costs can be reduced.

[0109] Modification of embodiments 1 and 2. The voltage value of the drive capability signal Vcap does not necessarily have to be the same as the voltage value of the adjustment signal Vref. In this modification, the adjustment unit 302 generates (updates) the drive capability signal Vcap in accordance with the adjustment signal Vref when a predetermined trigger condition is met.

[0110] Fig. 21 is a diagram illustrating an example of the configuration of an adjustment system in this modified example. Referring to Fig. 21, an adjustment system 80A1 differs from the adjustment system 80A (see Fig. 15) in that an adjustment unit 302 receives an output signal RS1 from a delay circuit 305. Note that the signal generation unit 46, the voltage sensor 47, and the terminal T2A are not essential. The adjustment system 80A1 may further include lands LND1 and LND2 and a wiring pattern PTN.

[0111] The delay circuit 305 receives the drive signal Vin as an input signal. The delay circuit 305 generates the output signal RS1 by delaying this input signal. The delay time given to the drive signal Vin is determined by the time constant of the delay circuit 305. This delay time is, for example, within a range from the order of single to double nanoseconds. In this example, the delay circuit 305 is included in the drive circuit 30A, but it may be provided outside the drive circuit 30A as long as it is included in the power conversion device 1.

[0112] In this example, the trigger condition is met when the output signal RS1 changes. In other words, the adjustment unit 302 generates (updates) the drive capability signal Vcap after a delay time from the time when the drive signal Vin changes (specifically, the time when the drive signal Vin rises or falls).

[0113] 22 is a timing diagram illustrating an example of the timing at which the drive capability signal Vcap is generated (updated). Referring to FIG. 22, the horizontal axis represents elapsed time. The vertical axis represents, from top to bottom, the adjustment signal Vref, the drive capability signal Vcap, and the drive signal Vin.

[0114] The control device 4 generates (updates) the drive capability signal Vcap in accordance with the adjustment signal Vref at a timing (e.g., time t11d, t12d, t13d) when a delay time td has elapsed since the rising edge of the drive signal Vin (e.g., time t11, t12, t13). The control device 4 may also generate the drive capability signal Vcap at a timing when a delay time td has elapsed since the falling edge of the drive signal Vin.

[0115] Noise may occur at the rising or falling edges of the drive signal Vin. If the drive capability signal Vcap is generated at such timing, the signal level (voltage value) of the drive capability signal Vcap may unintentionally change due to the influence of the noise. In this case, the switching speed of the switching element Q may unintentionally change. This is undesirable.

[0116] In this modification, the output signal RS1 changes after a delay time td from the rising or falling edge of the drive signal Vin. This establishes a trigger condition, and the drive capability signal Vcap is generated (updated). As a result, the drive capability signal Vcap is prevented from being generated at that timing. This prevents the switching speed from unintentionally changing, or from changing to an unintended switching speed at the intended timing.

[0117] Fig. 23 is a diagram showing another example of the configuration of an adjustment system according to this modification. Referring to Fig. 23, an adjustment system 80A2 differs from the adjustment system 80A (see Fig. 15) in that it further includes a voltage detection unit 304 and the adjustment unit 302 receives an output signal RS2 from a delay circuit 310. Note that the signal generation unit 46, the voltage sensor 47, and the terminal T2A are not essential. The adjustment system 80A2 may further include lands LND1 and LND2 and a wiring pattern PTN.

[0118] The voltage detection unit 304 is a power-on reset IC (Integrated Circuit) that detects the power supply voltage Vcc (i.e., power-on to the drive circuit 30A). When power is turned on to the drive circuit 30A, the voltage detection unit 304 generates a power-on reset signal POR. The power-on reset signal POR indicates that power is being turned on to the drive circuit 30A.

[0119] The delay circuit 310 receives the power-on reset signal POR as an input signal. The delay circuit 305 generates the output signal RS2 by delaying this input signal. The delay time of the delay circuit 310 is, for example, the same as the delay time td. In this example, the delay circuit 310 is included in the drive circuit 30A, but it may be provided outside the drive circuit 30A as long as it is included in the power conversion device 1.

[0120] In this example, the trigger condition is met when the output signal RS2 changes. In other words, after a delay time from the time when the power-on reset signal POR changes (the time when power is turned on), the adjustment unit 302 generates (updates) the drive capability signal Vcap according to the adjustment signal Vref.

[0121] Noise may occur when power is applied to the drive circuit 30A, so it is preferable that the drive capability signal Vcap be generated at a timing other than this timing.

[0122] In this example, the output signal RS2 changes after the delay time from the timing of power-on. This triggers the establishment of the trigger condition, and the drive capability signal Vcap is generated (updated). As a result, the drive capability signal Vcap is prevented from being generated at the timing of power-on. This prevents the switching speed from unintentionally changing.

[0123] Thus, in this modification, the power conversion device 1 further includes a delay circuit. This delay circuit generates an output signal by delaying its input signal (for example, the drive signal Vin or the power-on reset signal POR). The trigger condition is met when this output signal changes. This makes it possible to prevent the switching speed from being affected by noise and changing unintentionally.

[0124] Embodiment 3 Fig. 24 is a diagram showing an example of the configuration of an adjustment system according to Embodiment 3. Referring to Fig. 24, adjustment system 85 differs from each of adjustment systems 80, 80A, 80A1, and 80A2 in that adjustment system 85 includes an information terminal 77 instead of measuring device 70. In other respects (for example, the functions of signal generating unit 45, driving unit 301, and adjustment unit 302), adjustment system 85 is basically the same as each of adjustment systems 80 to 80A2 unless otherwise specified.

[0125] The information terminal 77 is provided outside the power conversion device 1 and stores reference information 79. The reference information 79 indicates a reference range (target range) of a target physical quantity such as the switching time of the switching element Q, the leakage current of the power conversion device 1, the power conversion efficiency or heat generation amount of the power conversion device 1, or the noise (volume) of the power conversion device 1. The reference range may be replaced by a reference value (target value).

[0126] The signal generating device 75 is configured to communicate with an information terminal 77 via wire or wirelessly. The signal generating device 75 stores a map 76. The map 76 represents a correspondence relationship between a numerical range of the value of the target physical quantity and a voltage value of the adjustment signal Vref. Specifically, this relationship represents a numerical range that the value of the target physical quantity can take when the voltage value of the adjustment signal Vref is Vk (1≦k≦5). The map 76 is determined in advance, for example, by experiment.

[0127] The signal generating device 75 acquires the reference information 79 from the information terminal 77, and uses the map to generate the adjustment signal Vref in accordance with the reference information 79. Specifically, the signal generating device 75 determines, based on the map, the voltage value of the adjustment signal Vref that corresponds to the numerical range including the reference range indicated by the reference information 79, and generates the adjustment signal Vref having the determined voltage value.

[0128] As a result, similarly to the first and second embodiments and their modifications, even when the target physical quantity deviates from the reference range, the switching speed of the switching element Q can be appropriately adjusted so that the target physical quantity falls within the reference range. As a result, loss or noise of the power conversion device 1 can be appropriately adjusted. In this case, in the description of the first and second embodiments and their modifications, the measurement information MI can be appropriately read as reference information 79.

[0129] The adjustment system 85 may further include a signal generating unit 46 and a voltage sensor 47. In this case, the storage device 43 stores voltage value information 43c. The adjustment system 85 may further include a delay circuit 305. Alternatively, the adjustment system 85 may further include a voltage detecting unit 304 and a delay circuit 310. In these examples, the functions of the signal generating unit 45, the driving unit 301, and the adjustment unit 302 are basically the same as those in the second embodiment and the modifications of the first and second embodiments. The adjustment system 85 may further include lands LND1 and LND2 and a wiring pattern PTN.

[0130] Other variations. In the above, the signal generating device 75 generates the adjustment signal Vref whose voltage value changes discretely, but it may also be configured to generate the adjustment signal Vref whose voltage value changes continuously.

[0131] The trigger condition may be set to be satisfied periodically (specifically, at predetermined time intervals), which can simplify the control for generating the drive capability signal Vcap.

[0132] If the adjustment unit 302 does not receive the adjustment signal Vref from the signal generating device 75, or if the voltage value of the adjustment signal Vref is outside the range of 0 to 5 V, the adjustment unit 302 may generate the drive capability signal Vcap so that the switching speed is adjusted to a predetermined speed.

[0133] With this configuration, even if the input of the adjustment signal Vref from the signal generating device 75 to the drive circuit 30 is stopped or the adjustment signal Vref is not generated properly, the switching element Q is driven at a predetermined switching speed. This prevents the switching speed from becoming excessively high or low. As a result, it is possible to reliably prevent noise or loss from becoming unintentionally large.

[0134] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0135] 1 power conversion device, 4 control device, 45, 46 signal generation unit, 70 measuring device, 75 signal generation unit, 77 information terminal, 80, 80A, 80A1, 80A2, 85 adjustment system, 301, 301A, 301B, 301C drive unit, 302 adjustment unit, Q, Q1, Q2, Q3, Q4, Q5, Q6 switching elements.

Claims

1. A power conversion device; a signal generating device provided outside the power conversion device, The power conversion device is A switching element; a drive circuit for driving the switching element; a signal generating unit that generates a first signal for controlling the switching timing of the switching element, the signal generating device is configured to generate a second signal having a discrete signal value for adjusting a switching speed of the switching element in accordance with a measurement result of a physical quantity of the power conversion device; the power converter further includes an input terminal configured to receive the second signal from the signal generator; the drive circuit drives the switching element in accordance with the first signal and the second signal; The drive circuit a drive unit that drives the switching element; an adjusting unit that generates a third signal having a discrete signal value for determining an adjustment value of the switching speed according to the second signal, and outputs the third signal to the driving unit; the driver adjusts the first signal in response to the third signal and outputs the adjusted first signal to the gate of the switching element as a gate signal of a discrete signal value; the physical quantity includes a switching time of the switching element, The signal generator generates the second signal so that the switching time approaches the reference.

2. A power conversion device; a signal generating device provided outside the power conversion device, The power conversion device is A switching element; a drive circuit for driving the switching element; a signal generating unit that generates a first signal for controlling the switching timing of the switching element, the signal generating device is configured to generate a second signal having a discrete signal value for adjusting a switching speed of the switching element in accordance with a measurement result of a physical quantity of the power conversion device; the power converter further includes an input terminal configured to receive the second signal from the signal generator; the drive circuit drives the switching element in accordance with the first signal and the second signal; The drive circuit a drive unit that drives the switching element; an adjusting unit that generates a third signal having a discrete signal value for determining an adjustment value of the switching speed according to the second signal, and outputs the third signal to the driving unit; the driver adjusts the first signal in response to the third signal and outputs the adjusted first signal to the gate of the switching element as a gate signal of a discrete signal value; the physical quantity includes a leakage current of the power conversion device, The signal generating device generates the second signal so that the switching speed is reduced when the leakage current is greater than the reference value.

3. the adjustment unit generates the third signal according to the second signal when a condition is met; The adjustment system according to claim 1 or 2, wherein the condition is met periodically.

4. the adjustment unit generates the third signal according to the second signal when a condition is met; the power conversion device further includes a delay circuit that generates an output signal by delaying an input signal; the input signal includes the first signal or a signal indicating power-on of the drive circuit; 3. The adjustment system according to claim 1, wherein the condition is met when the output signal of the delay circuit changes.

5. A power conversion device; a signal generating device provided outside the power conversion device, The power conversion device is A switching element; a drive circuit for driving the switching element; a signal generating unit that generates a first signal for controlling the switching timing of the switching element, the signal generating device is configured to generate a second signal having a discrete signal value for adjusting a switching speed of the switching element in accordance with a measurement result of a physical quantity of the power conversion device; the power converter further includes an input terminal configured to receive the second signal from the signal generator; The drive circuit a drive unit that drives the switching element; an adjustment unit that generates a third signal having a discrete signal value for determining an adjustment value of the switching speed in accordance with the second signal when the second signal is input from the signal generating device to the input terminal, and outputs the third signal to the drive unit; the driver adjusts the first signal in response to the third signal and outputs the adjusted first signal to the gate of the switching element as a gate signal of a discrete signal value; The power conversion device is a storage unit that stores a signal value of the second signal; a voltage divider circuit configured to divide a power supply voltage of a power supply node that constitutes a power supply of a control device of the power conversion device and generate a voltage signal having a divided voltage value; a voltage divider circuit control unit that controls the voltage divider circuit so as to supply the voltage signal having the signal value stored in the storage unit as the divided voltage value to the drive circuit when the input of the second signal from the signal generating device to the input terminal is stopped, an adjustment system, wherein the adjustment unit generates the third signal according to the voltage signal supplied from the voltage divider circuit when input of the second signal from the signal generating device to the input terminal is stopped.

6. A power conversion device, A switching element; a drive circuit for driving the switching element; a signal generating unit that generates a first signal for controlling the switching timing of the switching element; an input terminal configured to receive a second signal from outside the power conversion device; the second signal is generated according to a measurement result of a physical quantity of the power conversion device, and has a discrete signal value for adjusting a switching speed of the switching element; the drive circuit drives the switching element in accordance with the first signal and the second signal or a reproduced signal obtained by reproducing the second signal; The drive circuit a drive unit that drives the switching element; an adjusting unit that generates a third signal having a discrete signal value for determining an adjustment value of the switching speed according to the second signal or the reproduced signal, and outputs the third signal to the driving unit; the driver adjusts the first signal in response to the third signal and outputs the adjusted first signal to the gate of the switching element as a gate signal of a discrete signal value; The power conversion device is a storage unit that stores a signal value of the second signal; a voltage dividing circuit configured to divide a power supply voltage of a power supply node that constitutes a power supply of a control device of the power conversion device and generate a voltage signal having a divided voltage value as the reproduction signal; a voltage divider circuit control unit that controls the voltage divider circuit so as to supply the voltage signal having the signal value stored in the storage unit as the divided voltage value to the drive circuit when the input of the second signal from the outside to the input terminal is stopped, The adjustment unit generates the third signal in accordance with the voltage signal supplied from the voltage divider circuit.

7. A power conversion device, A switching element; a drive circuit for driving the switching element; a signal generating unit that generates a first signal for controlling the switching timing of the switching element; an input terminal configured to receive a second signal from outside the power conversion device; the second signal is generated according to a measurement result of a physical quantity of the power conversion device, and has a discrete signal value for adjusting a switching speed of the switching element; the drive circuit drives the switching element in accordance with the first signal and the second signal or a reproduced signal obtained by reproducing the second signal; The drive circuit a drive unit that drives the switching element; an adjusting unit that generates a third signal having a discrete signal value for determining an adjustment value of the switching speed according to the second signal or the reproduced signal, and outputs the third signal to the driving unit; the driver adjusts the first signal in response to the third signal and outputs the adjusted first signal to the gate of the switching element as a gate signal of a discrete signal value; The power conversion device is a land formed on a substrate of the power conversion device, to which a resistive element can be attached; a wiring pattern formed on a substrate of the power conversion device and provided between the land and the drive circuit, When the resistive element is attached to the land, the resistive element generates, as the reproduction signal, a divided voltage signal having a divided voltage value of a voltage of a power supply node that constitutes a power supply of a control device of the power conversion device, The wiring pattern is configured to transmit the voltage-divided signal to the input terminal.

8. The adjustment unit generates the third signal according to the second signal when a condition is met; The power conversion device according to claim 6 or 7, wherein the condition is met periodically.

9. The adjustment unit generates the third signal according to the second signal when a condition is met; the power conversion device further includes a delay circuit that generates an output signal by delaying an input signal; the input signal includes the first signal or a signal indicating power-on of the drive circuit; The power conversion device according to claim 6 or 7, wherein the condition is met when the output signal changes.

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