JP2020165680A - Plasma reactor system - Google Patents

Abstract

To provide a plasma reactor system capable of detecting an electric leakage and a decrease in insulation resistance.SOLUTION: A plasma reactor system 1 comprises a battery 2 and a plasma reactor 3, a power supply device 5, a ground wiring 6, a plasma wiring 7 and a minus wiring 8, a current difference sensor 11, and a control device 12. The current difference sensor 11 comprises a first current sensor 13 electrically connected to a plasma wiring 7 in a housing 51 and a minus wiring 8 in a housing 31. When a pressure rises, the control device 12 determines whether an electric leakage occurs on the basis of the current difference detected by the current difference sensor. When a constant pressure is applied, the control device determines whether insulation resistance decreases on the basis of the current difference detected by the current difference sensor.SELECTED DRAWING: Figure 2

Description

The present invention relates to a plasma reactor system.

Conventionally, a plasma reactor is known as a device for decomposing harmful components such as particulate matter (PM) contained in exhaust gas. In the plasma reactor, electric power is supplied to a pair of electrodes via a control circuit, and a discharge and plasma are generated between the electrodes to decompose harmful components.

As such a control device for a plasma reactor, for example, by controlling a gate drive circuit, the energization from the power supply device for the plasma reactor to the plasma reactor is switched on / off, and the application applied to the discharge electrode of the plasma reactor is applied. A control device for a plasma reactor has been proposed in which the current is monitored by a current sensor and the detection of the current sensor is used to determine whether or not an abnormal discharge has occurred in the plasma reactor (see, for example, Patent Document 1).

JP-A-2017-152341

On the other hand, in such a control device for a plasma reactor, a conductor (metal part, etc.) comes into contact with the circuit between the plasma reactor and the power supply device to form a new circuit (leakage circuit) to prevent leakage. May occur. In such a case, the conductor forming the earth leakage circuit may be damaged by the earth leakage. Further, at the time of electric leakage, if water droplets or carbon adhere to the circuit in the plasma reactor and the insulation resistance is lowered, the electric power leaked becomes large and the degree of damage to the conductor becomes large.

Therefore, when an electric leakage occurs in the plasma reactor, it is required to detect the presence or absence of a decrease in the insulation resistance.

The present invention is a plasma reactor system capable of detecting an electric leakage and a decrease in insulation resistance.

The present invention [1] comprises a battery and a plasma reactor, a power supply device for supplying electric power from the battery to the plasma reactor, the battery, the power supply device, and a ground wiring electrically connected to the plasma reactor, and the power supply device. Detected by the positive and negative wirings that electrically connect the and the plasma reactor, the current difference sensor that detects the difference between the current flowing through the positive wiring and the current flowing through the negative wiring, and the current difference sensor. The current difference sensor includes the positive wiring and / or the control means for determining the presence or absence of a decrease in insulation resistance in the negative wiring from the current difference, and the current difference sensor is the positive wiring and the plasma in the housing of the power supply device. At least a first current difference sensor that is electrically connected to the negative wiring in the housing of the reactor is provided, and the control device receives power from the power supply device to the plasma reactor when the power is supplied to the plasma reactor. The difference between the current flowing through the positive wiring and the current flowing through the negative wiring is detected at the time of boosting when the rate of change of the voltage applied to is equal to or higher than a predetermined value, and the current difference detected by the current difference sensor is obtained. Based on this, the presence or absence of electric leakage is determined, and when it is determined that electric leakage has occurred, the current is applied when a constant pressure is applied so that the rate of change of the voltage applied from the power supply device to the plasma reactor is less than a predetermined value. This is a plasma reactor system that determines whether or not the insulation resistance is reduced based on the current difference detected by the difference sensor.

In such a plasma reactor system, leakage occurs through the stray capacitance generated in the housing of the plasma reactor and the stray capacitance generated in the housing of the power supply device. That is, a stray capacitance (capacitor component) is interposed in the electric circuit (leakage circuit) through which the leaked power flows. A current flows through the stray capacitance (capacitor component) only when the voltage changes (for example, when boosting), and no current flows when a constant pressure is applied. Therefore, leakage occurs only when the voltage changes (for example, when boosting).

On the other hand, when the insulation resistance is lowered due to water droplets or carbon adhering to the electric circuit and causing a short circuit, electric power may leak in the portion where the insulation resistance is lowered. In such a case, the stray capacitance is not interposed in the circuit (resistance reduction circuit) of the portion where the insulation resistance is reduced. Therefore, power leakage through the resistance reduction circuit occurs not only when the voltage changes (for example, when boosting) but also when a constant pressure is applied.

Therefore, in the above plasma reactor system, when power is supplied to the plasma reactor, the difference between the current flowing through the positive wiring and the current flowing through the negative wiring is detected by the current difference sensor. Further, the current difference sensor includes at least a first current difference sensor that is connected to a positive wiring in the housing of the power supply device and a negative wiring in the housing of the plasma reactor and detects the current difference between them.

In such a plasma reactor system, first, at the time of boosting, the difference between the current flowing through the positive wiring and the current flowing through the negative wiring is detected. Then, the presence or absence of electric leakage is determined based on the current difference detected by the current difference sensor. Further, when it is determined that an electric leakage has occurred, the difference between the current flowing through the positive wiring and the current flowing through the negative wiring is detected even when a constant pressure is applied. Then, based on the current difference detected by the current difference sensor, it is determined whether or not the insulation resistance is reduced.

In such a plasma reactor system, if a current difference is detected by the current difference sensor during boosting, it can be determined that an electric leakage has occurred, and when a constant pressure is applied, the current difference is detected by the current difference sensor. Then, it can be determined that the insulation resistance is also lowered.

As described above, in the above plasma reactor system, it is possible to determine whether an electric leakage occurs or a decrease in insulation resistance occurs by detecting a current difference at the time of boosting and when a constant pressure is applied.

The present invention [2] includes the plasma reactor system according to the above [1], wherein the current difference at the time of boosting and the current difference at the time of applying the constant pressure are detected by the same current difference sensor.

In the above plasma reactor system, the current difference at the time of boosting and the current difference at the time of applying a constant pressure are detected by the same first current difference sensor. Therefore, the number of parts can be reduced, and leakage and reduction of insulation resistance can be detected at low cost.

In the present invention [3], the current difference sensor is further electrically connected to the positive wiring in the housing of the power supply device and the negative wiring in the housing of the power supply device, and flows through the positive wiring. A second current difference sensor for detecting the difference between the current and the current flowing through the minus wiring is provided, and the control device is detected by the second current difference sensor at the time of supplying power to the plasma reactor and at the time of boosting. The presence or absence of electric leakage is determined based on the current difference, and when it is determined that electric leakage has occurred, the insulation resistance is reduced based on the current difference detected by the first current difference sensor when a constant pressure is applied. Includes the plasma reactor system of [1] above, which determines the presence or absence of.

In such a plasma reactor system, the current difference at the time of boosting is detected by the second current difference sensor, while the current difference at the time of applying a constant pressure is detected by the first current difference sensor.

In this way, if the current difference at different timings is detected by different current difference sensors, electrical processing such as amplification processing and peak hold processing can be performed on the detected current difference, so that the detection is accurate. The property can be improved, and leakage and decrease in insulation resistance can be detected more reliably.

According to the plasma reactor system of the present invention, it is possible to detect an electric leakage in an electric circuit and a decrease in insulation resistance.

FIG. 1 is a schematic configuration diagram of a vehicle including an embodiment of the plasma reactor system of the present invention. FIG. 2 is a circuit diagram showing a power control system in the plasma reactor system shown in FIG. FIG. 3 is a schematic view showing an example of a current flow at the time of boosting in the power control system shown in FIG. 2 when an electric leakage occurs and an insulation resistance does not decrease. FIG. 4 is a schematic diagram showing an example of a current flow when a constant pressure is applied in the power control system shown in FIG. 2 when an electric leakage occurs and an insulation resistance does not decrease. FIG. 5 is a schematic view showing an example of a current flow at the time of boosting in the power control system shown in FIG. 2 when an electric leakage occurs and an insulation resistance is lowered. FIG. 6 is a schematic view showing an example of a current flow when a constant pressure is applied when an electric leakage occurs and an insulation resistance is lowered in the power control system shown in FIG. FIG. 7 is a schematic configuration diagram of a vehicle comprising another embodiment of the plasma reactor system of the present invention. FIG. 8 is a circuit diagram showing a power control system in the plasma reactor system shown in FIG. 7.

1. 1. Schematic of the plasma reactor system As shown in FIG. 1, the plasma reactor system 1 is mounted on, for example, a vehicle 100.

The vehicle 100 includes an engine 101, an intake system (not shown) for intake air into the engine 101, a fuel injection system (not shown) for supplying fuel to the engine 101, and an exhaust system 103 for exhausting from the engine 101. ..

The exhaust system 103 includes an exhaust pipe 104.

The exhaust pipe 104 is a pipe for exhausting the exhaust gas discharged from the engine 101. The exhaust pipe 104 is connected to the engine 101.

Further, the vehicle 100 includes a plasma reactor system 1.

The plasma reactor system 1 includes a battery 2, a plasma reactor 3, and a power control system 4.

(1) Battery Examples of the battery 2 include known secondary batteries such as lead storage batteries, nickel hydrogen batteries, and lithium ion batteries. The battery 2 is stored in a housing (case) such as a metal housing, for example.

(2) Plasma Reactor The plasma reactor 3 decomposes harmful components (for example, hydrocarbons (HC), nitrogen oxides (NOx), particulate matter (PM), etc.) contained in the exhaust gas discharged from the engine 101. The plasma reactor 3 is interposed in the middle of the exhaust pipe 104.

As shown in FIG. 2, the plasma reactor 3 has, for example, a housing (case) 31 such as a metal housing, and at least one pair of positive electrode panels 32 and negative electrode panels 33 housed in the housing 31. .. The positive electrode panel 32 and the negative electrode panel 33 face each other with a distance from each other. When power is supplied to the plasma reactor 3 via the positive wiring 7 (described later) and the negative wiring 8 (described later), an electric discharge occurs between the positive electrode panel 32 and the negative electrode panel 33. As a result, the gas between the positive electrode panel 32 and the negative electrode panel 33 becomes a plasma state. That is, plasma is generated in the plasma reactor 3.

Then, as shown in FIG. 1, harmful components contained in the exhaust gas flowing into the plasma reactor 3 through the exhaust pipe 104 are decomposed by the plasma in the plasma reactor 3. The exhaust gas that has passed through the plasma reactor 3 is discharged to the outside of the vehicle via the exhaust pipe 104.

Further, in the plasma reactor 3, as shown by a virtual line in FIG. 2, when power (pulse voltage) is supplied to the plasma reactor 3, when the voltage changes, the inside surface of the housing 31 of the plasma reactor 3 A stray capacitance 34 is generated between the positive wiring 7 (described later). That is, conduction is possible between the positive wiring 7 (described later) and the housing 31.

Such stray capacitance 34 occurs in a portion where the positive wiring 7 (described later) and the housing 31 are likely to conduct (for example, a portion where the positive wiring 7 (described later) and the housing 31 are close to each other). In other words, by appropriately designing the arrangement of the positive wiring 7 (described later), the shape of the housing 31, and the like to form a portion where the positive wiring 7 (described later) and the housing 31 can easily conduct with each other, an arbitrary shape can be obtained. A stray capacitance 34 can be generated at a location.

Further, in the plasma reactor 3, when electric power (pulse voltage) is supplied to the plasma reactor 3, when the voltage changes, between the inner surface of the housing 31 of the plasma reactor 3 and the minus wiring 8 (described later), A stray capacitance 35 is generated. That is, conduction is possible between the minus wiring 8 (described later) and the housing 31.

Such a stray capacitance 35 occurs, for example, in a portion where the negative wiring 8 (described later) and the housing 31 are likely to conduct (for example, a portion where the negative wiring 8 (described later) and the housing 31 are close to each other). In other words, by appropriately designing the arrangement of the minus wiring 8 (described later), the shape of the housing 31, and the like to form a portion where the minus wiring 8 (described later) and the housing 31 can easily conduct with each other, an arbitrary shape can be obtained. A stray capacitance 35 can be generated at a location.

In FIG. 1, the positive wiring 7 (described later) and the negative wiring 8 (described later) arranged in the housing 31 of the plasma reactor 3 are shown by broken lines, respectively.

(3) Electric Power Control System The electric power control system 4 is a system that controls the supply and stop of electric power from the battery 2 to the plasma reactor 3.

As shown in FIGS. 1 and 2, the power control system 4 includes a power supply device 5, a ground wiring 6, a positive wiring 7 and a negative wiring 8, a current difference sensor 11, and a control device 12.

(4) Power supply device The power supply device 5 supplies electric power from the battery 2 to the plasma reactor 3. Specifically, the power supply device 5 includes a housing (case) 51 such as a metal housing, a booster circuit (for example, a flyback converter) 52 arranged in the housing 51, and a switch circuit (for example, not shown). It is equipped with a gate drive circuit, etc.).

The power supply device 5 is electrically connected to the battery 2 via the power supply wiring 21. The switch circuit (not shown) is electrically connected to the control device 12 via the signal wiring 22 as shown by the broken line in FIG.

Then, when the control device 12 turns on the switch circuit (not shown), the power supply device 5 supplies electric power from the battery 2 to the plasma reactor 3. Further, when the control device 12 turns off the switch circuit, the power supply device 5 stops the power supply from the battery 2 to the plasma reactor 3.

Further, in the power supply device 5, as shown by a broken line in FIG. 2, when power (pulse voltage) is supplied to the plasma reactor 3, when the voltage changes, the inner surface of the housing 51 of the power supply device 5 is positive. A stray capacitance 54 is generated between the wiring 7 (described later). That is, conduction is possible between the positive wiring 7 (described later) and the housing 51.

Such stray capacitance 54 occurs in a portion where the positive wiring 7 (described later) and the housing 51 are likely to conduct (for example, a portion where the positive wiring 7 (described later) and the housing 51 are close to each other). In other words, by appropriately designing the arrangement of the positive wiring 7 (described later), the shape of the housing 51, and the like to form a portion where the positive wiring 7 (described later) and the housing 51 can easily conduct with each other, an arbitrary shape can be obtained. A stray capacitance 54 can be generated at a location.

Further, in the power supply device 5, when power (pulse voltage) is supplied to the plasma reactor 3, when the voltage changes, between the inner surface of the housing 51 of the power supply device 5 and the minus wiring 8 (described later), A stray capacitance 55 is generated. That is, conduction is possible between the minus wiring 8 (described later) and the housing 51.

Such a stray capacitance 55 occurs, for example, in a portion where the minus wiring 8 (described later) and the housing 51 are likely to conduct each other (for example, a portion where the minus wiring 8 (described later) and the housing 51 are close to each other). In other words, by appropriately designing the arrangement of the minus wiring 8 (described later), the shape of the housing 51, etc., and forming a portion where the minus wiring 8 (described later) and the housing 51 are easily conducted, an arbitrary shape can be obtained. A stray capacitance 55 can be generated at a location.

Further, in the power supply device 5, as shown by a broken line in FIG. 2, when electric power (pulse voltage) is supplied to the plasma reactor 3, stray capacitance 56 is generated in the booster circuit 52 when the voltage changes. More specifically, as shown in FIG. 2, when the booster circuit 52 is a flyback converter, stray capacitance 56 is generated on each of the plus side and the minus side of the pair of coils, and the space between the pair of coils is It becomes conductive.

(5) Ground wiring The ground wiring 6 is a ground (ground) electrically connected to the battery 2, the power supply device 5, and the plasma reactor 3. In the ground wiring 6, for example, the housing of the battery 2 (not shown), the housing 51 of the power supply device 5, and the housing 31 of the plasma reactor 3 are connected in parallel.

More specifically, the ground wiring 6 includes a first ground 61 that electrically connects the ground main line 60, the housing of the battery 2 (not shown), and the ground main line 60, and the housing of the power supply device 5. A second ground 62 that electrically connects the 51 and the ground main line 60, and a third ground 63 that electrically connects the housing 31 of the plasma reactor 3 and the ground main line 60 are provided. As a result, the ground wiring 6 makes it possible to ground the current leaking from the battery 2, the power supply device 5, and the plasma reactor 3.

More specifically, the ground wiring 6 includes, for example, a metal body of the vehicle 100.

That is, by arranging the housing of the battery 2 (not shown), the housing 51 of the power supply device 5, and the housing 31 of the plasma reactor 3 in contact with the metal body of the vehicle 100, the vehicle 100 The metal body can be used as the ground wiring 6.

(6) Positive Wiring and Minus Wiring The positive wiring 7 and the negative wiring 8 are wirings that electrically connect the power supply device 5 and the plasma reactor 3.

Specifically, the positive wiring 7 is electrically connected to the positive terminal of the power supply device 5 in the housing 51 of the power supply device 5, and is electrically connected to the positive electrode panel 32 in the housing 31 of the plasma reactor 3. Be connected.

Further, the negative wiring 8 is electrically connected to the negative terminal of the power supply device 5 in the housing 51 of the power supply device 5, and is electrically connected to the negative electrode panel 33 in the housing 31 of the plasma reactor 3. Will be done.

In FIG. 1, the positive wiring 7 and the negative wiring 8 arranged in the housing 51 of the power supply device 5 are shown by broken lines, respectively.

(7) Current difference sensor The current difference sensor 11 measures the current flowing through the positive wiring 7 and the current flowing through the negative wiring 8, respectively, and determines the current flowing through the positive wiring 7 and the current flowing through the negative wiring 8. It is a sensor that detects the difference (current difference).

The current difference sensor 11 includes at least a first current difference sensor 13. In the embodiment shown in FIGS. 1 and 2, the current difference sensor 11 includes a first current difference sensor 13.

The first current difference sensor 13 has a positive side sensor 17 for measuring the magnitude (current value) of the current flowing through the positive wiring 7, and a negative sensor 13 for measuring the magnitude (current value) of the current flowing through the negative wiring 8. It includes a side sensor 18 and an output unit 19 that outputs a current difference as an electric signal.

The positive side sensor 17 is connected in the housing 51 of the power supply device 5 to a portion downstream of the stray capacitance 54 on the positive wiring 7 side in the flow direction of electricity.

The minus side sensor 18 is connected in the housing 31 of the plasma reactor 3 to a portion downstream of the stray capacitance 33 on the minus wiring 8 side in the flow direction of electricity.

The output unit 19 is electrically connected to the plus side sensor 17 and the minus side sensor 18. That is, the output unit 19 is electrically connected to the positive wiring 7 in the housing 51 of the power supply device 5 and the negative wiring 8 in the housing 31 of the plasma reactor 3. The output unit 19 is electrically connected to the control device 12 via the signal wiring 23 as shown by the broken line in FIG. As a result, the output unit 19 makes a difference between the current flowing through the positive wiring 7 (current value measured by the positive side sensor 17) and the current flowing through the negative wiring 8 (current value measured by the negative side sensor 18). It is possible to output the corresponding electric signal. The electric signal output by the output unit 19 is input to the control device 12 via the signal wiring 23.

(9) Control device The control device 12 is an ECU (Electronic Control Unit) that executes electrical control in the vehicle 100, and includes a CPU, a ROM, a RAM, and the like.

Further, as described above, the control device 12 is electrically connected to the current difference sensor 11. Then, as will be described in detail later, the control device 12 can determine the leakage and the decrease in insulation resistance based on the electric signal output by the current difference sensor 11.

2. Operation of Plasma Reactor System The plasma reactor system 1 operates, for example, to decompose harmful components in the exhaust gas discharged from the exhaust pipe 104 when the engine 101 is driven.

More specifically, when the engine 101 is driven, electric power is supplied from the battery 2 to the plasma reactor 3 via the power supply device 5 under the control of the control device 12 at a predetermined timing. As a result, an electric discharge is generated between the positive electrode panel 32 and the negative electrode panel 33, and the gas between the positive electrode panel 32 and the negative electrode panel 33 is in a plasma state. That is, plasma is generated in the plasma reactor 3. Then, the generated plasma decomposes harmful components in the exhaust gas.

On the other hand, when the plasma reactor 3 is operated as described above, when a conductor such as a metal part comes into contact with the circuit between the plasma reactor 3 and the power supply device 5, an electric leakage circuit 70 is formed and an electric leakage occurs. In such a case, the conductor forming the leakage circuit 70 may be damaged by the leakage. Further, in the case of electric leakage, if water droplets or carbon adhere to the circuits of the plasma reactor 3 or the power supply device 5 and the insulation resistance is lowered, the electric power leaked becomes large and the degree of damage to the conductor becomes large. Become.

Therefore, in the above plasma reactor system 1, the presence / absence of electric leakage and the presence / absence of decrease in insulation resistance are detected based on the current difference detected by the current difference sensor 11 by the following control.

3. 3. Control of Plasma Reactor System The control method for determining whether or not the insulation resistance is reduced on the negative wiring 8 side when an electric leakage occurs on the positive wiring 7 side will be described in detail below.

Specifically, in the above-mentioned plasma reactor system 1, first, a pulse voltage is applied from the power supply device 5 to the plasma reactor 3 under the control of the control device 12, and the plasma reactor 3 is operated.

On the other hand, in this control, the power supply to the plasma reactor 3 is divided into boosting and constant pressure application.

More specifically, when power is supplied to the plasma reactor 3, the frequency of the voltage applied from the power supply device 5 to the plasma reactor 3 is equal to or higher than a predetermined threshold value (for example, 50 Hz or higher, preferably 10 kHz or higher). Time is defined as boosting. On the other hand, the time when the frequency of the voltage is less than the above threshold value is defined as the time when the constant pressure is applied.

Then, in this control, the difference between the current flowing through the positive wiring 7 and the current flowing through the negative wiring 8 during boosting during power supply to the plasma reactor 3 is determined by the current difference sensor 11 (first current difference sensor 13). ) To detect.

That is, in the plasma reactor system 1, leakage occurs through the stray capacitance generated in the housing 31 of the plasma reactor 3 and the stray capacitance generated in the housing 1 of the power supply device 5. That is, a stray capacitance (capacitor component) is interposed in the electric circuit (leakage circuit) through which the leaked power flows. A current flows through the stray capacitance (capacitor component) only when the voltage changes (for example, when boosting), and no current flows when a constant pressure is applied. Therefore, leakage occurs only when the voltage changes (for example, when boosting).

Therefore, at the time of boosting, the magnitude (current value) of the current flowing through the positive wiring 7 is measured by the positive side sensor 17, and the magnitude (current value) of the current flowing through the negative wiring 8 is measured by the negative side sensor 18. Measured by. Then, an electric signal corresponding to the difference between them is output from the output unit 19 to the control device 12 via the signal wiring 23.

At this time, as shown in FIG. 2, when there is no electric leakage between the power supply device 5 and the plasma reactor 3, the current flowing through the positive wiring 7 maintains its magnitude (current value). Then, it flows through the minus wiring 8.

That is, the difference between the current value measured by the plus side sensor 17 and the current value measured by the minus side sensor 18 is 0 (or its error range). In such a case, the control device 12 determines that no electric leakage has occurred.

On the other hand, as shown in FIG. 3, when an electric leakage occurs between the power supply device 5 and the plasma reactor 3, a current leaks to a circuit other than the positive wiring 7 and the negative wiring 8. Therefore, the magnitude of the current (current value) of the positive wiring 7 and the magnitude (current value) of the current of the negative wiring 8 are different from each other.

More specifically, for example, as shown in FIG. 3, when a conductor (metal part or the like) comes into contact with the positive wiring 7 and the ground wiring 6 (metal body or the like), a positive side leakage circuit 70A is formed. Will be done.

At this time, the position of the contact α between the positive side leakage circuit 70A and the positive wiring 7 is usually in the middle of the positive wiring 7, downstream of the positive side sensor 17, and is with the housing 51 of the power supply device 5. , The portion between the plasma reactor 3 and the housing 31.

In such a case, when the plasma reactor 3 is operated, a part of the current supplied from the power supply device 5 passes through the positive side sensor 17 and then leaks (leaks) from the contact α to the positive side leakage circuit 70A. .. Then, the leaked current passes through, for example, the ground wiring 6, the housing 31 of the plasma reactor 3, the housing 51 of the power supply device 5, and returns to the power supply device 5 via the stray capacitance 55.

As an example, FIG. 3 shows a route in which the leaked current returns to the power supply device 5 via the positive side leakage circuit 70A, the ground main line 60, the second ground 62, the housing 51 of the power supply device 5, and the stray capacitance 55. Shown in.

That is, if an electric leakage occurs on the positive wiring 7 side at the time of boosting, the current leaks to the electric leakage circuit 70 after passing through the positive side sensor 17 and returns to the power supply device 5 without passing through the negative side sensor 18.

Therefore, when the positive side leakage circuit 70A is formed, the current flowing through the positive wiring 7 (current value measured by the positive side sensor 17) is the current flowing through the negative wiring 8 (minus side sensor 18) at the time of boosting. The current value measured by) is larger than.

In other words, during boosting, the current flowing through the positive wiring 7 (current value measured by the positive side sensor 17) is larger than the current flowing through the negative wiring 8 (current value measured by the negative side sensor 18). When the difference is equal to or greater than the threshold value of the error range, it is determined that electric leakage occurs on the positive wiring 7 side and the positive side electric leakage circuit 70A is formed. The threshold value of the current difference is, for example, 20 mA or more, preferably 5 mA or more, and for example, 1000 mA or less, preferably 100 mA or less. The current difference detected by the current difference sensor 11 (first current difference sensor 13) can be processed by, for example, an inverting amplifier circuit, a full-wave rectifier circuit, or the like, if necessary.

Subsequently, in this control, the difference between the current flowing through the positive wiring 7 and the current flowing through the negative wiring 8 is determined by the current difference sensor 11 (when power is supplied to the plasma reactor 3 and a constant pressure is applied after boosting. It is detected by the first current difference sensor 13).

That is, when the insulation resistance is lowered due to water droplets or carbon adhering to the electric circuit and causing a short circuit, electric power may leak at the portion where the insulation resistance is lowered. In such a case, the stray capacitance is not interposed in the circuit (resistance reduction circuit) of the portion where the insulation resistance is reduced. Therefore, power leakage through the resistance reduction circuit occurs not only when the voltage changes (for example, when boosting) but also when a constant pressure is applied.

Therefore, in this control, the magnitude of the current flowing through the positive wiring 7 (current value) is measured by the positive side sensor 17 and the magnitude of the current flowing through the negative wiring 8 (current value) even when a constant pressure is applied. The current value) is measured by the minus side sensor 18. Then, an electric signal corresponding to the difference between them is output from the output unit 19 to the control device 12 via the signal wiring 23.

However, when such a constant pressure is applied, electric leakage does not occur through the stray capacitance as described above.

Therefore, as shown in FIG. 4, when the insulation resistance does not decrease between the power supply device 5 and the plasma reactor 3, the current flowing through the positive wiring 7 has a magnitude (current value). Maintain and flow through the minus wiring 8.

That is, the difference between the current value measured by the plus side sensor 17 and the current value measured by the minus side sensor 18 is 0 (or its error range). In such a case, the control device 12 determines that the insulation resistance has not decreased.

On the other hand, as shown in FIG. 5, when both leakage and reduction of insulation resistance occur between the power supply device 5 and the plasma reactor 3, both when boosting and when applying constant pressure, Since current leaks to circuits other than the positive wiring 7 and the negative wiring 8 (leakage circuit and resistance reduction circuit), the magnitude of the current in the positive wiring 7 (current value) and the magnitude of the current in the negative wiring 8 (current). Value) and are different from each other.

More specifically, for example, as shown in FIG. 5, when a conductor (metal part or the like) comes into contact with the positive wiring 7 and the ground wiring 6 (metal body or the like), a positive side leakage circuit 70A is formed. Will be done.

At this time, the position of the contact α between the positive side leakage circuit 70A and the positive wiring 7 is usually in the middle of the positive wiring 7, downstream of the positive side sensor 17, and is with the housing 51 of the power supply device 5. , The portion between the plasma reactor 3 and the housing 31.

Further, in the minus wiring 8, when water droplets or carbon adhere to the minus wiring 8 to cause a short circuit or the like, the minus side resistance lowering circuit 70B is formed.

At this time, the position of the contact β between the negative side resistance reduction circuit 70B and the negative wiring 8 is usually in the middle of the negative wiring 8 and on the downstream side of the negative side sensor 18, and the housing 51 of the power supply device 5 And the portion between the housing 31 of the plasma reactor 3.

In such a case, when the plasma reactor 3 is operated, a part of the current supplied from the power supply device 5 passes through the positive side sensor 17 and then leaks from the contact α to the positive side leakage circuit 70A as described above. (Leak). Then, the leaked current passes through, for example, the ground wiring 6, the housing 31 of the plasma reactor 3, the housing 51 of the power supply device 5, and returns to the power supply device 5 via the stray capacitance 55.

Further, a part of the leaked current passes through the negative resistance lowering circuit 70B and the contact β, and returns to the power supply device 5.

As an example, a route in which the leaked current returns to the power supply device 5 via the positive side leakage circuit 70A, the ground main line 60, the second ground 62, the housing 51 of the power supply device 5, and the floating capacity 55, and the positive side. FIG. 5 shows a route that passes through the earth leakage circuit 70A, the ground main line 60, the negative side resistance reduction circuit 70B, and the contact β, and returns to the power supply device 5.

That is, even when both leakage and a decrease in insulation resistance occur, the current leaks to the leakage circuit 70 after passing through the plus side sensor 17 and does not pass through the minus side sensor 18 to the power supply device. Return to 5.

Therefore, when the positive side leakage circuit 70A is formed, the current flowing through the positive wiring 7 (current value measured by the positive side sensor 17) is measured by the current flowing through the negative wiring 8 (minus side sensor 18). It becomes larger than the current value).

In other words, the current flowing through the positive wiring 7 (current value measured by the positive side sensor 17) is larger than the current flowing through the negative wiring 8 (current value measured by the negative side sensor 18), and the difference is an error. If it is equal to or more than the threshold value in the range, it is determined that electric leakage occurs on the positive wiring 7 side and the positive side electric leakage circuit 70A is formed.

Subsequently, in this control, even when a constant pressure is applied, the magnitude of the current flowing through the positive wiring 7 (current value) is measured by the positive side sensor 17, and the magnitude of the current flowing through the negative wiring 8 is also measured. (Current value) is measured by the minus side sensor 18. Then, an electric signal corresponding to the difference between them is output from the output unit 19 to the control device 12 via the signal wiring 23.

However, when such a constant pressure is applied, electric leakage does not occur through the stray capacitance as described above.

However, on the other hand, even when a constant pressure is applied, power leakage occurs via the negative resistance lowering circuit 70B.

More specifically, in the above electric circuit in which the positive side leakage circuit 70A is formed, when a decrease in insulation resistance occurs on the negative wiring 8 side when a constant pressure is applied, as shown in FIG. After passing through the positive side sensor 17, a part of the current supplied from the power supply device 5 leaks from the contact α to the positive side leakage circuit 70A, and causes the ground main line 60, the negative side resistance reduction circuit 70B, and the contact β. It passes and returns to the power supply device 5.

That is, even when a constant pressure is applied, electric power leaks from the positive wiring 7 side and returns to the power supply device 5 via the negative side resistance reduction circuit 70B without passing through the negative side sensor 18.

Therefore, when the positive side leakage circuit 70A and the negative side resistance reduction circuit 70B are formed, the current flowing through the positive wiring 7 (current value measured by the positive side sensor 17) becomes negative even when a constant pressure is applied. It becomes larger than the current flowing through the wiring 8 (the current value measured by the minus side sensor 18).

In other words, at the time of boosting, the current flowing through the positive wiring 7 (current value measured by the positive side sensor 17) is larger than the current flowing through the negative wiring 8 (current value measured by the negative side sensor 18). When the difference is equal to or greater than the threshold value of the error range, it is determined that the insulation resistance is lowered on the minus wiring 8 side. As the threshold value of the current difference, the threshold value of the current difference is, for example, 20 mA or more, preferably 5 mA or more, and for example, 1000 mA or less, preferably 100 mA or less. The current difference detected by the current difference sensor 11 (first current difference sensor 13) can be processed by, for example, an inverting amplifier circuit, a full-wave rectifier circuit, or the like, if necessary.

Further, when the insulation resistance is lowered, the voltage difference detected when a constant pressure is applied is usually higher than the voltage difference detected when boosting.

As described above, the control device 12 can detect the occurrence of electric leakage and the occurrence of decrease in insulation resistance by detecting the current difference at the time of boosting and at the time of applying constant pressure, respectively. Then, when the control device 12 detects, for example, an electric leakage and / or a decrease in the insulation resistance, the control device 12 executes a safety process such as stopping the plasma reactor 3 as necessary.

4. Action / Effect As described above, in the above plasma reactor system 1, when power is supplied to the plasma reactor 3, the difference between the current flowing through the positive wiring 7 and the current flowing through the negative wiring 7 is detected by the current difference sensor 11. Further, the current difference sensor 11 is connected to at least the positive wiring 7 in the housing 51 of the power supply device 5 and the negative wiring 8 in the housing 31 of the plasma reactor 3, and is the first to detect the current difference between them. The current difference sensor 13 is provided.

In such a plasma reactor system, first, at the time of boosting, the difference between the current flowing through the positive wiring 7 and the current flowing through the negative wiring 8 is detected. Then, the presence or absence of electric leakage is determined based on the current difference detected by the current difference sensor 11. Further, when it is determined that an electric leakage has occurred, the difference between the current flowing through the positive wiring 7 and the current flowing through the negative wiring 8 is detected even when a constant pressure is applied. Then, based on the current difference detected by the current difference sensor 11, it is determined whether or not the insulation resistance is reduced.

In such a plasma reactor system 1, if a current difference is detected by the current difference sensor 11 at the time of boosting, it can be determined that an electric leakage has occurred, and at the time of applying a constant pressure, the current difference is detected by the current difference sensor 11. When is detected, it can be determined that the insulation resistance has also decreased.

As described above, in the above plasma reactor system 1, it is possible to determine whether an electric leakage occurs or a decrease in insulation resistance occurs by detecting a current difference at the time of boosting and when a constant pressure is applied.

Further, in the plasma reactor system 1, the current difference at the time of boosting and the current difference at the time of applying a constant pressure are detected by the same first current difference sensor 13. Therefore, the number of parts can be reduced, and leakage and reduction of insulation resistance can be detected at low cost.

5. Modification example In the above plasma reactor system 1, only the first current difference sensor 13 is used as the current difference sensor 11, and the current difference at the time of boosting and the current difference at the time of applying a constant pressure are the same first current difference sensor. It is detected by 13.

On the other hand, as shown in FIGS. 7 and 8, the current difference sensor 11 may include a second current difference sensor 14 in addition to the first current difference sensor 13 described above.

In this embodiment, the first current difference sensor 13 is the plus side sensor 17 (hereinafter referred to as the first plus side sensor 17A) for measuring the magnitude (current value) of the current flowing through the plus wiring 7 in the same manner as described above. To measure the magnitude (current value) of the current flowing through the minus wiring 8, the minus side sensor 18 (hereinafter referred to as the first minus side sensor 18A) and the output that outputs the current difference as an electric signal. A unit 19 (hereinafter referred to as a first output unit 19A) is provided.

The second current difference sensor 14 measures the magnitude (current value) of the current flowing through the minus wiring 8 and the second plus side sensor 17B for measuring the magnitude (current value) of the current flowing through the plus wiring 7. Therefore, it is provided with a second minus side sensor 18B and a second output unit 19B that outputs a current difference as an electric signal.

The second positive side sensor 17B is connected to a portion downstream of the stray capacitance 54 on the positive wiring 7 side in the housing 51 of the power supply device 5 in the direction of electricity flow. As shown in FIG. 8, as the second plus side sensor 17B, for example, the first plus side sensor 17A can also be used.

The second negative side sensor 18B is connected to a portion downstream of the stray capacitance 33 on the negative wiring 8 side in the electric flow direction in the housing 51 of the power supply device 5.

The second output unit 19B is electrically connected to the second positive side sensor 17B and the second negative side sensor 18B. That is, the second output unit 19B is electrically connected to the positive wiring 7 in the housing 51 of the power supply device 5 and the negative wiring 8 in the housing 51 of the power supply device 5. The second output unit 19 is electrically connected to the control device 12 via the signal wiring 24 as shown by the broken line in FIG. 7. As a result, the second output unit 19B has the current flowing through the positive wiring 7 (current value measured by the second positive side sensor 17B) and the current flowing through the negative wiring 8 (current measured by the second negative side sensor 18B). It is possible to output an electric signal according to the difference from the value). The electric signal output by the second output unit 19B is input to the control device 12 via the signal wiring 24.

Then, in this embodiment, as follows, the current difference at the time of boosting is detected by the second current difference sensor 14 instead of the first current difference sensor 13.

More specifically, as shown in FIG. 8, in this embodiment as well, the positive side leakage circuit 70A and the negative side resistance reduction circuit 70B may be formed as described above. In such a case, when the plasma reactor 3 is operated, at the time of boosting the voltage, a part of the current supplied from the power supply device 5 passes through the positive side sensor 17, and then from the contact α to the positive side leakage circuit 70A. Leakage (leakage). Then, the leaked current passes through, for example, the ground wiring 6, the housing 31 of the plasma reactor 3, the housing 51 of the power supply device 5, and returns to the power supply device 5 via the stray capacitance 55 (see FIG. 5). ).

Further, a part of the leaked current passes through the negative side resistance reduction circuit 70B and the contact β and returns to the power supply device 5 (see FIG. 5).

Therefore, the current value measured by the second plus side sensor 17B is larger than the current value measured by the second minus side sensor 18B.

On the other hand, similarly to the above, if the positive side leakage circuit 70A and the negative side resistance reduction circuit 70B are formed, electricity leaks even when a constant pressure is applied.

More specifically, in the above electric circuit in which the positive side leakage circuit 70A is formed, when a decrease in insulation resistance occurs on the negative wiring 8 side when a constant pressure is applied, as shown in FIG. After passing through the positive side sensor 17, a part of the current supplied from the power supply device 5 leaks from the contact α to the positive side leakage circuit 70A, and causes the ground main line 60, the negative side resistance reduction circuit 70B, and the contact β. It passes and returns to the power supply device 5 (see FIG. 6).

That is, even when a constant pressure is applied, electric power leaks from the positive wiring 7 side and returns to the power supply device 5 via the negative side resistance reduction circuit 70B without passing through the negative side sensor 18.

Therefore, when the positive side leakage circuit 70A and the negative side resistance reduction circuit 70B are formed, the current value measured by the first positive side sensor 17A is measured by the first negative side sensor 18A when a constant pressure is applied. It will be larger than the measured current value.

Therefore, similarly to the above, the control device 12 can detect the occurrence of electric leakage and the occurrence of decrease in insulation resistance by detecting the current difference at the time of boosting and at the time of applying constant pressure, respectively. Then, when the control device 12 detects, for example, an electric leakage and / or a decrease in the insulation resistance, the control device 12 executes a safety process such as stopping the plasma reactor 3 as necessary.

Further, in the above embodiment, the current difference at the time of boosting is detected by the second current difference sensor 14, while the current difference at the time of applying a constant pressure is detected by the first current difference sensor 13.

In this way, if the current difference at different timings is detected by different current difference sensors (first current difference sensor 13 and second current difference sensor 14), the detected current difference is amplified and held. Since electrical processing such as processing can be performed, the accuracy of detection can be improved, and leakage and decrease in insulation resistance can be detected more reliably.

In the above description, the mode in which electric leakage occurs on the positive wiring 7 side and the insulation resistance decreases on the negative wiring 8 side has been described, but electric leakage occurs on the negative wiring 8 side and insulation occurs on the positive wiring 7 side. Similarly, when the resistance is reduced, the leakage and the decrease in the insulation resistance can be detected.

1 Plasma Reactor System 2 Battery 3 Plasma Reactor 5 Power Supply 6 Earth Wiring 7 Plus Wiring 8 Minus Wiring 31 Housing 51 Housing

Claims (3)

With batteries and plasma reactors,
A power supply that supplies power from the battery to the plasma reactor,
A ground wire that is electrically connected to the battery, the power supply, and the plasma reactor.
Positive wiring and negative wiring that electrically connect the power supply device and the plasma reactor,
A current difference sensor that detects the difference between the current flowing through the positive wiring and the current flowing through the negative wiring, and
A control means for determining the presence or absence of a decrease in insulation resistance in the positive wiring and / or the negative wiring from the current difference detected by the current difference sensor is provided.
The current difference sensor is
At least a first current difference sensor that is electrically connected to the positive wiring in the housing of the power supply device and the negative wiring in the housing of the plasma reactor is provided.
The control device
When supplying power to the plasma reactor
The current difference sensor detects the difference between the current flowing through the positive wiring and the current flowing through the negative wiring during boosting when the rate of change of the voltage applied from the power supply device to the plasma reactor is equal to or higher than a predetermined value. Judging the presence or absence of electric leakage based on the current difference detected by
When it is determined that an electric leakage has occurred,
When a constant pressure is applied so that the rate of change of the voltage applied from the power supply device to the plasma reactor is less than a predetermined value, it is determined whether or not the insulation resistance is reduced based on the current difference detected by the current difference sensor. A featured plasma reactor system. The plasma reactor system according to claim 1, wherein the current difference at the time of boosting and the current difference at the time of applying a constant pressure are detected by the same first current difference sensor. The current difference sensor is
Further, it is electrically connected to the positive wiring in the housing of the power supply device and the negative wiring in the housing of the power supply device, and detects the difference between the current flowing through the positive wiring and the current flowing through the negative wiring. Equipped with a second current difference sensor
The control device
When supplying power to the plasma reactor
When boosting, the presence or absence of electric leakage is determined based on the current difference detected by the second current difference sensor, and when it is determined that electric leakage has occurred,
The plasma reactor system according to claim 1, wherein when a constant pressure is applied, the presence or absence of a decrease in insulation resistance is determined based on the current difference detected by the first current difference sensor.

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