JP6375466B1 - Simple emergency power supply device - Google Patents

Abstract

[Objective] The present invention is capable of supplying emergency power with high efficiency using a small gas engine having a displacement of 50 cc to 500 cc and an AC generator even if power outage accidents continue intermittently even multiple times. [Structure] A small LPG gas engine 1, an AC generator 3, and a storage battery 51 are provided. A spark plug 13, an intake valve 15, a spark plug 13, and an exhaust valve 17 are arranged around the cylinder 11 when viewed in plan, and intake air from the intake valve 15 is tangential when the cylinder 11 is viewed in plan. Or configured to flow in a direction approximating a tangent. At the moment when the commercial power supply is lost due to some accident or the like, power is supplied from the storage battery 51 to the power supply side, and during this time, the gas engine 1 is started and the AC generator 3 generates electric power. The supply of power from the storage battery 51 is stopped when the power reaches the value, and the AC power generated by the gas engine 1 is continuously supplied to the indoor circuit. [Selection] Figure 1

Description

  The present invention relates to a simple emergency power supply device that can supply emergency power with high efficiency even when power outage accidents continue intermittently a plurality of times or using a small gas engine and an AC generator.

  There are two types of emergency power supply devices (such as uninterruptible power supply devices) of less than 10 kW that are used for homes and signs in preparation for disasters. The storage battery has advantages such as a short time from power failure to lighting and simpleness, but has a large disadvantage that the mass is increased.

  For example, find the mass of a storage battery when supplying 1kW of power for 72 hours (3 days when it is possible to recover infrastructure destroyed by a disaster). Since 1kW is 1kJ / s, in 72 hours, 1kJ / s x 72 x 3600s = 259200kJ. However, since the storage battery is a direct current, assuming that the efficiency of the inverter that converts this into alternating current is 93%, the storage battery must at least store electrical energy of 259200 kJ / 0.93 = 278710 kJ (≈2797 MJ). Even a lithium ion battery having a large energy density (electric energy per unit mass) is at most 100 Wh / kg, so 100 J / s × 3600 s = 360,000 J = 360 kj, that is, 360 kj per kg. Therefore, the mass of the storage battery is 278710 kJ / (360 kJ / kg) = 774 kg.

  On the other hand, power generation by the engine can generate power as long as the fuel continues, but it takes several tens of seconds to start the engine and supply a stable electrical output, and power outages continue during this time. Furthermore, when the required power (electric load) suddenly increases because the small device has little surplus power as described above, the rotation speed of the engine decreases and the power supply cannot catch up, or the engine stops. Sometimes. As described above, both the storage battery type and the engine generator have a big problem.

  In addition, Patent Document 1 exists as an AC uninterruptible power supply, but this document is not for commercial power supply, but is used in mountainous areas, remote islands, etc. The engine is used in this device, but the configuration is completely different.

  In Patent Document 2, the storage battery and the engine are uninterruptible power supplies, but the capacity of the storage battery is reduced so that power can be supplied by the engine. In the case where the commercial power source is lost, the cited document 2 cannot be dealt with at all.

Japanese Patent Laid-Open No. 5-207684 JP 2001-45681 A

  The problem (technical problem or purpose, etc.) to be solved by the present invention is not a large-scale emergency power generation device, but a small power supply that easily supplies power not only to home use but also to traffic lights, various signs, and surveillance cameras. An emergency power supply apparatus is provided. Moreover, in the event of a power outage, AC power with the same voltage and frequency as the main power supply can be supplied without interruption, and can continue to be supplied for 3 days. It is to realize that it can sufficiently cope with the loss.

  Therefore, as a result of intensive research and studies to solve the above problems, the inventor has achieved the invention of claim 1 with a small LPG gas engine having a displacement of 50 cc to 500 cc and an alternating current that generates electric power by starting the gas engine. A generator, a direct current storage battery for power supply, an engine battery, a plurality of on / off switches, and a general control unit for controlling the on / off switches, and two cylinders of the gas engine The first spark plug, the intake valve, the second spark plug, and the exhaust valve are arranged around the circumference when the cylinder is viewed in plan, and intake air from the intake valve is The cylinder is configured to flow in a tangential direction or a direction approximating the tangent when viewed in a plan view, and in a normal state, the cylinder is commercialized via the on / off switch. The power supply side of the power supply is energized, and at the moment when the commercial power supply is lost due to some accident or the like, the AC power from the storage battery via the inverter is supplied with the same frequency and the same frequency as the commercial power supply. While supplying power to the power supply side, the gas engine having the above-described configuration is started by the engine battery from the moment when the commercial power supply is lost, and the AC power is generated by the AC generator using the starting force. When the gas engine reaches a predetermined number of revolutions, the supply of power from the storage battery is stopped, and at the same time, AC power generated by the gas engine is supplied to the power supply side until the commercial power is restored. The above-described problem has been solved by providing a simple emergency power supply device characterized in that power is continuously supplied only by the power of the gas engine.

  According to a second aspect of the present invention, in the simplified emergency power supply device according to the first aspect, the storage battery and the engine battery can be used regardless of the electric power generated by the gas engine at the time of the accident or the electric power at the normal time. The above-mentioned problem has been solved by providing a simple emergency power supply device characterized in that it provides a charging action. According to a third aspect of the present invention, in the simplified emergency power supply device according to the first or second aspect, the intake valve, the first spark plug, the exhaust valve, and the second spark plug of the gas engine include: The problem was solved by using a simple emergency power supply device characterized by being divided into four equal parts. According to a fourth aspect of the present invention, in the simplified emergency power supply device according to any one of the first, second, and third aspects, the main flow of the air-fuel mixture flowing into the cylinder of the gas engine is an ignition of the spark plug. The above-mentioned problem has been solved by providing a simple emergency power supply device characterized in that it is constructed so that it does not hit a point directly and flows in the vicinity thereof.

  According to a fifth aspect of the present invention, in the simplified emergency power supply device according to any one of the first, second, third and fourth aspects, a flywheel is provided between the gas engine and the AC generator. The above-described problems have been solved by using a simple emergency power supply device characterized by the above. The simplified emergency power supply apparatus according to claim 5, wherein the flywheel and the AC generator are spline-coupled, and As a result, the above problems have been solved. The invention according to claim 7 is the simplified emergency power supply device according to any one of claims 1, 2, 3, 4, 5 or 6, wherein the on / off switch is an on / off relay switch. The above-described problem is solved by using a simple emergency power supply device characterized by the above.

  According to the first aspect of the present invention, the present invention can cope well even when the commercial power supply is lost several times due to a catastrophic disaster or the like. This is because even a power failure can be stored by a gas engine. In addition, by using the storage battery only at the moment of a power failure, its mass is reduced to 1/350 or less, and the power from the storage battery is switched to the power generated by the engine by simple on / off switch control. Since the electrical energy previously consumed in the unit is replenished, there is an advantage that it can sufficiently cope with repeated power outages.

  Furthermore, in the first and second aspects of the invention, the rotational inertia energy is increased and stable electric power is supplied by increasing the rotational inertia energy because the output is difficult to follow an unfavorable sudden load increase due to the small engine. In addition, the storage battery terminal voltage and the voltage after the generated alternating current is converted to direct current are made the same to prevent a very short voltage drop. In addition, the effect of LPG, which exists everywhere in Japan, enables extremely efficient support and restoration in an emergency.

  In the inventions of claims 3 and 4, in particular, the combustion efficiency can be increased and the gas engine can be started up well. According to the fifth and sixth aspects of the present invention, the engine stall can be prevented. According to the seventh aspect of the invention, the relay device can be provided at a low cost with a simple configuration.

It is a block diagram at the normal time of this invention when electric power is normally supplied from main power supplies, such as an electric power company and a private generator. It is a block diagram of the transient state of the supply state which is supplying the electric power from the emergency storage battery of this invention of the moment when supply from the main power supply stopped. It is a block diagram of a state when the gas engine operates and power is stably supplied from the AC generator in an emergency. It is a simple flowchart figure which shows the operation state of this invention. It is a chart which shows the flow of the present invention. (A) is a plan view of a single cylinder location, (B) is an enlarged cross-sectional view taken along line Y1-N-O-X in (A), and (C) is an enlarged cross-sectional view taken along arrow Y2-Y2 in (A). is there. It is an expansion state perspective view of a single cylinder location. (A) is an enlarged side view in which a part of a crankshaft of a gas engine and a flywheel are separated from each other in a partial cross-section, and (B) is a part of the crankshaft after the flywheel is fixed to the flywheel. It is an enlarged state figure made into the partial section which attaches the drive shaft of an alternator. (A) is a partially enlarged side view showing a partial cross-section of another embodiment of the flywheel mounting location, and (B) is a sudden increase in electrical load when a flywheel having a large rotational inertia is mounted. 6 is a graph comparing the reduction effect of the engine speed and the improvement effect of the output recovery characteristic due to the engine.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 to FIG. 3 are configuration diagrams and state diagrams showing operations of the present invention. FIG. 1 is a configuration diagram in a normal state, and FIGS. 2 and 3 are operation state diagrams in an emergency. In these figures, originally two wires are required for single-phase AC and DC, and three wires are required for three-phase AC. However, for easy understanding of the figure, the connection relationship is represented by a single line. I will represent it.

  FIG. 1 shows a state in which commercial power is supplied in a normal state from a private power generation facility such as a power plant, factory, or ship. The main configuration of the present invention includes a small gas engine 1, an AC generator 3 that generates power when the gas engine 1 is started, a DC storage battery 51 for power supply, a plurality of on / off switches, A general control unit 61 (also referred to as “TCU”) for controlling an on / off switch, an engine control unit 62 (also referred to as “ECU”) supplied from a low-voltage engine battery 52, and the like are provided.

  In FIG. 1, a power generation device including a gas engine 1, a fuel supply device 2, and an AC generator 3 is used, and a gas cylinder 29 for liquefied petroleum gas (LPG) is used as fuel. Since it is a small emergency power source, the gas engine 1 has a small displacement of about 50 cc to about 500 cc or less. The gas engine 1 is a multi-point ignition engine in which two ignition plugs are arranged in one cylinder. As a result, opportunities for ignition can be increased, and rapid combustion can be realized to improve fuel efficiency.

  In the gas engine 1, a cylinder head 12 is provided on an upper portion of a cylinder 11 in which a piston 10 is housed so as to be movable up and down, and a lower surface of the cylinder head 12 is formed as a flat spherical concave surface 12a. Two spark plugs 13, an intake valve 15, and an exhaust valve 17 are provided as viewed in plan from the upper surface side of the cylinder head 12 (or the cylinder 11). Specifically, the intake valve 15, the first spark plug 13, the exhaust valve 17, and the second spark plug 13 are arranged around the circumference in four equal parts (see FIG. 6A).

  A radius of curvature R of the flat spherical concave surface 12 a is located at an arbitrary point P on the central axis n of the cylinder 11. Further, the central axis m of the two spark plugs 13, the central axis w of the intake valve 15, and the central axis u of the exhaust valve 17 are configured to pass on the point P, respectively. That is, the center axis m of the spark plug 13, the center axis w of the intake valve 15 (inlet part of the intake port 14), and the center axis u of the exhaust valve 17 (outlet part of the exhaust port 16) have the curvature radius R. It exists on the normal line of the spherical surface of the flat spherical concave surface 12a. Such a three-dimensional combustion chamber is configured.

  In particular, the intake port 14 that allows the intake valve 15 to intake air flows into the cylinder 11 from a direction tangential to or close to the tangent when the cylinder 11 is viewed in plan view, and the vortex ( Swirl G). When the piston 10 in the cylinder 11 is lowered, this swirl S (vortex) is generated.

  Directionality may be secured even in the swirl S (vortex). In order to ensure sufficient directionality, the following configuration is often used. In particular, on the lower side of the flat spherical concave surface 12a, a bulging portion 12b having a substantially crescent shape or trapezoidal mountain shape is on the near side of the first single spark plug 13, and the swirl S (vortex) It is provided so as to be on the downstream side. The details of the swirl S (vortex) will be described in detail. The main flow of the swirl S (vortex) does not directly hit the ignition point of the first spark plug 13 and flows in the vicinity thereof (FIG. 6). (See (A)).

  The bulging portion 12b has a substantially crescent shape and a vertical cross section having a substantially triangular shape (see FIGS. 6A and 6B), and functions to change the flow of the swirl S (vortex). Yes, the highest height may be around 1 mm. Even at the bulging portion 12b, the swirl S (vortex) can cause a small turbulent state. Further, the bulging portion 12b is the same as the crescent-shaped bulging portion 12b described above, even if it is formed in a trapezoidal mountain shape that flattened Mt. The effect of. Moreover, the said bulging part 12b will not be limited to the shape, if the directionality of the said swirl S (vortex | eddy_current) can be changed.

  Furthermore, in FIGS. 6A and 6B, the flow rate of the main flow versus the counter main flow is preferably about 8 to 2. Since the anti-main flow exists, the turbulence of the air flow is generated, and mixing (mixing) and gas (LPG) combustion can be further promoted. Such a configuration is a great advantage that does not exist in the prior art. In particular, as shown in FIG. 7, the main flow in the swirl S (vortex flow) exhibits a fine turbulent flow state at the same time as the velocity gradually decreases in the cylinder 11 due to the anti-main flow. However, it is possible to unify the gas air (air) and the gas LPG.

  If the main flow of strong swirl S (vortex) hits the ignition point (spark gap) of the spark plug 13 directly, the temperature of this portion decreases (for example, 450 ° C. or less), free carbon is generated, and the tip is soiled. As a result, it is difficult for the spark to fly, but a new air-fuel mixture is allowed to flow into the ignition point (spark gap) while avoiding the direct hit of the tip. Once fire is ignited, the swirl S (vortex) causes the flame to spread three-dimensionally into the combustion space (the entire space defined by the cylinder head 12, the inner wall surface of the cylinder 11 and the top surface of the piston 10). Gas combustion efficiency can be significantly increased.

This combustion efficiency is extremely good in combination with the three-dimensional combustion chamber as the spherical surface of the flat spherical concave surface 12a having the radius of curvature R and the swirl S (vortex) avoiding the ignition point of the spark plug 13. The effect which becomes. Furthermore, the gas engine 1 can be started immediately after a power outage with the greatest advantage that it can be started very quickly.
Note that the angle θ between the center axis m of the spark plug 13 and the center axis n of the cylinder 11 and the angle θ between the center axis w of the intake valve 15 and the center axis n of the cylinder 11 are both the exhaust valve 17. The angle θ between the central axis u of the cylinder 11 and the central axis n of the cylinder 11 is also the same angle and is configured to be about 12 ° to about 14 °.

  The gas cylinder 29 is provided with a pressure reducing valve 28 from which a supply pipe 25 is disposed, and the other end of the supply pipe 25 communicates with the orifice 18 a of the intake duct 18 in front of the intake port 12. Has been. LPG flows into the gas pipe 25 through the electromagnetic valve 27 and the pressure regulating valve 26 into the intake port 12 and is finally ejected by appropriately opening the throttle 21 by the throttle actuator 22. That is, the fuel supply device 2 includes the lottle 21, the throttle actuator 22, the gas pipe 25, the pressure regulating valve 26, the electromagnetic valve 27, the pressure reducing valve 28, and the gas cylinder 29.

  As described above, liquefied petroleum gas (LPG) that is easily available and filled in the gas cylinder 29 and is convenient for transportation is used as the fuel. The LPG has an advantage that it does not deteriorate like gasoline and light oil even after long-term storage. Furthermore, it has the advantages of shorter start-up time and less carbon dioxide and nitrogen oxide emissions than conventional compression ignition diesel engines using light oil as fuel. In the figure, 44 is a radiator and 45 is a fan motor.

  The DC storage battery 51 for commercial power supply is a power supply used in an emergency, and the storage capacity of the storage battery 51 will be described. The time from when the gas engine 1 is started until stable power is supplied from the AC generator 3 is about 10 seconds to about 40 seconds. The power to cover this time is 1 kJ / s × 40 s = 40 kJ at maximum, assuming that the power output from P2 is 1 kW. However, assuming that the conversion efficiency at which the inverter 71 makes a predetermined alternating current is 93%, 40 kJ / 0.93 = 43 kJ.

  In the case where the storage battery 51 is a general lithium ion battery, the energy density is about 360 kJ / kg. Therefore, (43 kj) / (360 kJ / kg) = 0.12 kg may be stored to store 43 kj of electric energy. Become. However, the battery has an energy density (kJ / kg) and an output density (W / kg). In the case of a lithium ion battery, since this is about 700 W / kg, (1.08 kW) / (0.7 kW / kg) ≈1.6 kg is necessary to output 1 kW / 0.93 = 1.08 kW.

  The mass of the battery that simultaneously satisfies the energy density and the power density is 1.6 kg or more. Where the breakage is good, if there is 2 kg, the predetermined power can be sufficiently supplied until the power generation by the engine is stabilized. As described above, the supply time of the electric energy from the storage battery 51 is until the gas engine 1 of the AC generator 3 is started, and the power supply time is short. In order to further shorten it, it is essential to shorten the startup time of the gas engine 1.

  Further, in the daily life of FIG. 1, the engine battery 52 is converted into a low voltage (for example, 12V) direct current by the power conditioner 74 and charged (see broken line). Further, the emergency storage battery 51 is also charged through an AC → DC inverter 71 (see broken line). The engine battery 52 may be a 12V lead / dilute sulfuric acid battery for automobiles, and the storage battery 51 may be a lithium ion battery, a lithium ion capacitor, a nickel metal hydride battery or the like with a full charge control function. .

  In FIG. 1, the electric power of the total control unit (TCU) 61 is supplied from a low-voltage engine battery 52 in the same manner as the engine control unit (ECU) 62. This is to avoid the use of the high-voltage emergency storage battery 51 because there are two types of power sources for control.

  In the state of FIG. 1, since the power from the storage battery 51 and the AC generator 3 is not used, the on / off switches 82, 84, 85 of this circuit (commercial power output side from the storage battery 51 and the AC generator 3) are in the open position. Is retained. The state of the commercial power supply (whether or not electricity is coming) is determined by the voltage applied to the integrated control unit (TCU) 62 from P1 through the fixed resistor 91 and the main power supply signal line 90. This is because the presence of the fixed resistor 91 allows the total control unit (TCU) 62 to determine whether or not a power failure occurs with a weak current. If there is a resistance in the total control unit (TCU) 62 and the voltage before and after this is monitored, if the main power supply (commercial power supply) is lost, this voltage becomes zero.

  In the normal state, as shown in FIG. 1, the on / off switch 83 is closed, and the power from the main power supply is output via P1 to P2 as indicated by a thick arrow. The on / off switch 83 has a function of turning on / off the circuit with a signal from the total control unit (TCU) 61. The switch may be an electromagnetic contact opening / closing or a normal contactless switch using a transistor.

  Next, an explanation of the operation in an emergency will be described with reference to FIGS. When it is detected that the commercial power source has been lost due to some accident or the like, in FIG. 1, the on / off switches 81 and 83 are opened by the operation of the integrated control unit (TCU) 61, and the on / off switch 82, 85 closes. At this time, if a time constant is provided in the output signal of the total control unit (TCU) 61 and the closing of each is delayed even by several ms, an emergency short circuit can be avoided. The on / off switch 84 remains open.

  The on / off states of the above-described on / off switches 82, 85, 81, 83, and 84 are instantaneous, and these are in the state shown in FIG. 2 (emergency: transition period). That is, at the moment when the commercial power source is lost due to some accident or the like, the contact part P2 is supplied with the AC power having the same frequency as the commercial power source from the emergency storage battery 51 via the inverter 71. After that, it is supplied to the power supply side.

  In other words, at the moment when the commercial power supply is lost, the power stored in the emergency storage battery 51 passes through the on / off switch 85 which is closed, and the main part is connected from the contact point P4 to the DC → AC inverter 71 as indicated by the arrow. The voltage and frequency are the same as those of the power supply, and output to the power supply side through the closed on / off switch 82 and the contact point P2. 1 to 3, a solid arrow indicates the direction of power output, and a dotted arrow indicates a charging operation state.

  Further, when the on / off switch 83 is opened, the electric power from the storage battery 51 flows to the general control unit 61 via P2, so that the general control unit 61 does not erroneously recognize that the main power source has been restored. Similarly, the on / off switch 83 is opened to prevent backflow. Even though the electric power is still small, it is converted into direct current again from the contact point P <b> 2 via the power conditioner 74 and charged to the engine battery 52. In particular, a charging action can be provided even in an emergency.

  Next, the characteristics of the present invention when generating power in the gas engine 1 in FIG. 3 and continuing to supply power over a long period of time will be described. Before the gas engine 1 starts, the process is described. Is described. First, when the total control unit (TCU) 61 detects the loss of commercial power (main power), the signal is transmitted from the total control unit (TCU) 61 to the engine control unit (ECU) 62.

  In response to a signal from the engine control unit (ECU) 62, the starter relay 42 drives the starter motor 41 with the power source of the engine battery (12V) 52. At the same time, the signal from the engine control unit (ECU) 62 is energized to open the electromagnetic valve 27 that has shut off the gas that has flowed from the gas cylinder 29 (for LPG) through the mechanical pressure reducing valve 28 that is normally used.

  At the same time, the pressure regulating valve 26 that adjusts the pressure of the fuel at almost atmospheric pressure is operated, so that the fuel is supplied to the fuel supply device 2 of the gas engine 1. On the other hand, the supply of engine oil essential for the operation of the gas engine 1 is circulated by the electric oil pump 46, and the cooling water is also circulated by the electric water pump 47.

  When the starter motor 41 rotates, the gas engine 1 is cranked and the fuel and air measured by the fuel supply device 2 are sucked in by the negative pressure generated by the suction, and then compressed and ignited to start. This startability is remarkably superior to that of a diesel engine because of multipoint ignition (two spark plugs 13 are provided) and gas fuel.

  When the gas engine 1 starts and reaches the rated speed, and power can be supplied from the AC generator 3 that rotates at the same speed, the on / off switch is turned off from the state of FIG. 2 as shown in FIG. Change. Here, the rotational speed of the gas engine 1 is calculated by counting the top dead center signal for ignition timing control detected by the crank sensor 48. The opening degree of the throttle 20 of the fuel supply device 2 is adjusted by a signal from the engine control unit (ECU) 62 so that this becomes a predetermined rotational speed, for example, 2000 rpm.

  The on / off switch 83 remains open, but the on / off switch 81 and the on / off switch 84 are closed. Further, the on / off switch 85 which has been closed so far is opened to cut off the circuit from the storage battery 51 to P4. The AC generator 3 is a normal three-phase AC of about 200V. The alternating current thus generated is converted into direct current by an alternating current → direct current inverter 73.

  The converted DC voltage is made equal to that of the emergency storage battery 51. For example, in the case of a lithium ion battery having a cell voltage of 1.6 V, if 60 packs in series are double-rowed to 96 V, the output voltage of the AC → DC inverter 73 is made the same. This is because the inputs of the direct current to alternating current inverter 73 are kept even in the emergency state of FIG. 2 even when the gas engine 1 is in a transitional state until the start, or when the gas engine 1 generates power. .

  Since the on / off switch 84 is closed, the direct current from the alternating current → direct current inverter 73 is supplied from P4 as indicated by the arrow, exactly the same as that supplied from the storage battery 51 of FIG. The inverter 73 converts the direct current into alternating current of the same power and frequency as the main power source, and outputs it from the P2 through the on / off switch 82.

  At this time, since the on / off switch 81 (see FIG. 3) is closed, a part of the electric power generated by the gas engine 1 and converted again into alternating current by the direct current to alternating current inverter 73 is as indicated by a broken line, From P 2, it is converted into direct current by the direct current → alternating current inverter 73 through the on / off switch 81, and supplied to the storage battery 51 for charging.

  Thereby, the electric energy reduced by the previous discharge is replenished until full charge. This emergency charging function is a great advantage. This is to prepare for when the main power supply is restored or lost. Likewise, the engine battery 52 is also charged by being converted into a low voltage direct current by the power conditioner 74.

  When the cooling water temperature rises during operation of the gas engine 1, the thermostat 43 is opened and the cooling water circulates through the radiator 44. Further, when the water temperature rises, the fan motor 45 is energized, and the heat radiation from the radiator 44 is promoted by the cooling air.

Next, fuel consumption and power generation energy resulting therefrom will be described. As an example, a case is assumed where a gas cylinder 29 in which 20 kg of propane C ₃ H ₈ is filled is used. C ₃ H _{8 has} a molecular weight of 44, ie 1 mole, and a mass of 22.4 liters in a standard state (0 ° C., 1 atm) is 44. On the other hand, the low calorific value (hereinafter abbreviated as calorific value) of propane in the standard state is 90.7 MJ / m ³ .

The mass of 1 m ³ of C ₃ H ₈ is 44 g × 1000 / 22.4 = 1964 g. Therefore, in the standard state (20kg) / propane ^{(1.964kg / m 3) = 10.18m} 3 is filled with 20kg cylinder. Its calorific value becomes ^{90.7MJ / m 3 × 10.18m 3 =} 923MJ (= 923 × 10 3 kJ). Obtain electric energy that can generate electricity with this amount of heat, and examine whether 1 kW can be supplied for 72 hours.

The thermal efficiency obtained with a multi-point ignition engine rotating at low speed with low friction loss is 36%. The efficiency of the generator is 95%, and the conversion efficiencies of the two converters AC → DC and DC → AC, and DC → AC inverters 72 and 73 are both 93%. Also, assuming that the output from the P2 terminal is kept at the maximum 1kW, the energy consumed by the engine repeats the conversion twice, so (1kJ / s) / (0.36 × 0.95 × 0.93 × 0.93) = 3.381kJ / s Become. The time to consume 923 × 10 ³ kJ is (923 × 10 ³ kJ) / (3.381 kJ / s) ≈273000 s, that is, 75.8 hours. Power generation for 75 hours or more is possible with one 20kg cylinder, and the target 72 hours can be achieved with a margin.

  When the commercial power supply (main power supply) recovers, the integrated control unit (TCU) 61 is informed, opens the on / off switches 82 and 84, and closes the on / off switch 83 to start the main power supply from P1. Power is supplied. The engine control unit (ECU) 62 stops the engine and simultaneously closes the electromagnetic valve 27 to shut off the fuel. Then, the state returns to the state of FIG.

  Here, the switching speed of each on / off switch is 10 ms at the slowest. On the other hand, the afterimage time of healthy human eyes is 1/16 seconds, that is, 62.5 ms. This means that a momentary power failure is not noticed by the human eye. Assume that the required electrical output suddenly increases when the gas engine 1 is rotating at a rated rotational speed with an output lower than a predetermined output. The engine speed decreases as the load increases. In order to recover this, the throttle of the fuel supply device 2 is opened by a signal from the engine control unit (ECU) 62, but it takes a short time to return to the predetermined rotational speed.

  In a small engine with a small output capacity, this cannot be countered, and the output voltage of P2 may decrease, or the gas engine 1 may stop in an extreme case. On the other hand, it is also effective to temporarily release the electric power from the storage battery 51, but it is necessary that the gas engine itself can cope with a sudden increase in load even if it is a small engine. As such means, a flywheel 9 may be provided.

  As shown in FIGS. 8A and 8B, the structure includes a thick outer peripheral portion 91, a thin disc portion 92, and a central boss portion 93. A mold spline 94 is provided. The flywheel 9 is fixed to the end of the crankshaft 19 of the gas engine 1 with a fastening bolt 95.

  A male spline 31 provided at the center of the AC generator 3 is fitted and fixed to the female spline 94 of the flywheel 9. It is mounted with a very simple configuration. Further, as shown in FIG. 9A, a separate boss portion 96 having the female spline 94 may be provided. In this case, the flywheel 9 can be made of casting, and the separate boss portion 96 can be made of steel to reinforce the spline attachment location.

When the rotational moment of inertia Ip (unit: kgm ² ) is large, the descending rotation becomes slow. The engine speed immediately after entering is higher than the conventional type. If it is high, the number of suctions is large, so the time from the mixer until the cylinder 1 is filled is shortened. Then, the amount of the air-fuel mixture supplied during that time increases. A large amount of heat energy is generated, that is, it blows up powerfully. The magnitude of the rotational moment of inertia Ip is 1.2kgm ² ~1.0kgm ² at engine 100Cc～300cc, is substantially the same size as the spark ignition engine of 4 cylinder 2000Cc～3500cc.

  FIG. 9B is a chart comparing the graph of the present invention provided with the flywheel 9 and the prior art. In the prior art, a sudden electric load is generated in the gas engine 1 in an emergency. Sometimes, the engine speed decreases, the rise falls to the engine stall limit, and the convergence (convergence) is slow, but the convergence (convergence) time by the start-up of the present invention is about half, making it extremely difficult to stall. There are advantages.

  Each of the on / off switches 81, 82, 83, 84, 85 may be configured as an on / off relay switch. Mainly due to economic efficiency. The flowchart of FIG. 4 represents the basic steps of the present invention. Furthermore, the table of FIG. 5 particularly shows the features of the present invention.

  In other words, as in the bottom row, even if a power failure and recovery continue at predetermined time intervals (from 1 day to 3 days), the emergency storage battery 51 and the like are charged even in an emergency. by. Such a configuration is the greatest advantage that did not exist in the past. For example, recently, it is an invention that can sufficiently cope with the case where the seismic intensity 7 continues twice within 24 hours due to the Kumamoto earthquake.

  Generally, when the throttle 20 which is a known technique is appropriately opened, LPG flows into the intake duct 18 from the orifice 18a, but it is just as if tap water flows in, and LPG is also a gas. Air is a situation in which it is difficult to mix, and as described above, this is a gas engine 1 having good combustion efficiency because air and LPG are mixed well by the swirl S phenomenon in the cylinder 11 described above. Can provide.

DESCRIPTION OF SYMBOLS 1 ... Gas engine, 11 ... Cylinder, 12 ... Cylinder head, 13 ... Spark plug,
15 ... Intake valve, 17 ... Exhaust valve, 12a ... Flat spherical concave surface, 12a ... Swelling part,
2 ... Fuel supply device, 3 ... Alternator, 51 ... Storage battery, 52 ... Engine battery,
61 ... Total control unit (TCU), 9 ... Flywheel,
81, 82, 83, 84, 85 ... ON / OFF switch.

Claims (7)

A small LPG gas engine having a displacement of 50 cc to 500 cc, an AC generator for generating power by starting the gas engine, a DC storage battery for power supply, an engine battery, and a plurality of on / off switches, A general control unit for controlling the on / off switch;
The gas engine cylinder is provided with two spark plugs, and a first spark plug, an intake valve, a second spark plug, and an exhaust valve are arranged around the circumference when the cylinder is viewed in plan. In addition, the intake air from the intake valve is configured to flow in a tangential direction or a direction approximating the tangential line when the inside of the cylinder is viewed in a plane.
In a normal state, the commercial power supply side is energized through the on / off switch, and the commercial battery is urgently passed through the inverter from the storage battery at the moment when the commercial power is lost due to some accident or the like. The AC power having the same voltage as the power source and the same frequency is fed to the power supply side, and the gas engine having the above-described configuration is started by the engine battery from the moment when the commercial power source is lost to To generate power with the AC generator,
When the gas engine that is generating power reaches a predetermined number of revolutions, the supply of power from the storage battery is stopped. At the same time, AC power generated by the gas engine is supplied to the power supply side, and the commercial power supply A simple emergency power supply apparatus characterized in that power is supplied only by the power of the gas engine until the return.   2. The simplified emergency power supply device according to claim 1, wherein a charging action is provided to the storage battery and the engine battery regardless of power from the gas engine at the time of the accident or power at a normal time. A simple emergency power supply device characterized by:   3. The simplified emergency power supply apparatus according to claim 1, wherein the intake valve, the first spark plug, the exhaust valve, and the second spark plug of the gas engine are arranged in four equal parts. A simplified emergency power supply device characterized by   4. The simplified emergency power supply device according to claim 1, wherein the mainstream of the air-fuel mixture flowing into the cylinder of the gas engine does not directly hit the ignition point of the spark plug, and A simple emergency power supply device configured to flow in the vicinity thereof.   5. The simplified emergency power supply device according to claim 1, wherein a flywheel is provided between the gas engine and the AC generator. Simple emergency power supply device.   6. The simplified emergency power supply apparatus according to claim 5, wherein the flywheel and the AC generator are spline-coupled.   The simplified emergency power supply device according to any one of claims 1, 2, 3, 4, 5, or 6, wherein the on / off switch is an on / off relay switch. Emergency power supply device.

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