JP2019122220A - Simplified emergency power supply device - Google Patents

Abstract

PURPOSE: To allow for supply of emergency power with high efficiency even if intermittent blackout accidents occur multiple times or frequently, using a compact gas engine having a displacement of 50-500 cc and a DC generator.CONSTITUTION: An emergency power supply device comprises a compact LPG gas engine 1, a DC generator 3 and a storage battery 51. In the plan view of a cylinder 11, an ignition plug 13, an intake valve 15, an ignition plug 13 and an exhaust valve 17 are disposed around the circumference. Also, in the plan view of inside the cylinder 11, an in-flow of an intake air from the intake valve 15 is formed in the tangential direction or a direction approximate to the tangential direction. At the moment when 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 period, the gas engine 1 is started up to generate power by the DC generator 3. When the gas engine 1 reaches a predetermined revolution speed, the supply of power from the storage battery 51 is stopped, and using the power generated by the gas engine 1, the supply of AC power to an indoor circuit is continued.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a simplified emergency power supply device capable of efficiently supplying emergency power using a small gas engine and a direct current generator even if a power failure accident continues intermittently several times or many times.

  As a small emergency power supply device (such as an uninterruptible power supply device) at the time of a power failure less than 10 kW used for household use or signs in preparation for disaster etc., there is a method of generating electricity by a storage battery type and an engine. The storage battery has advantages such as short time from power failure to lighting and simplicity, but has a large disadvantage of large mass.

  For example, try to find the mass of the storage battery when supplying 1 kW of power for 72 hours (three days when restoration of the infrastructure destroyed by the disaster is about to be achieved). Since 1 kW is 1 kJ / s, in 72 hours, 1 kJ / s × 72 × 3600s = 259200 kJ. However, since the storage battery is a direct current, assuming that the efficiency of the inverter for converting this into an alternating current is 93%, the storage battery must store at least 259200 kJ / 0.93 = 278710 kJ (≒ 2797 MJ) of electric energy. The energy density (electrical energy per unit mass) is 100 Wh / kg at most even in a large lithium ion battery, so 100 J / s × 3600 s = 360000 J = 360 kj, ie, 360 kj per kg. Therefore, the mass of the storage battery is 278910 kJ / (360 kJ / kg) = 774 kg.

  On the other hand, although power generation by the engine can generate power as long as fuel continues, it takes several tens of seconds to start the engine and supply stable electrical output, and power failure will continue during this period. Furthermore, when the required power (electric load) suddenly increases due to the small remaining capacity of the small device as described above, the rotational speed of the engine decreases and the power supply can not catch up or the engine stops. Sometimes. As described above, both the storage battery type and the engine generator have serious problems.

  Moreover, although patent document 1 exists as an alternating current uninterruptible power supply, this document is not for commercial power supplies, but is used by mountainous part, a detached island, etc. Especially the fall of a frequency is carried out by inverter control. Although the engine is used in this device, it is completely different as a configuration.

Moreover, in patent document 2, although it is an uninterruptible power supply device with a storage battery and an engine,
Although the capacity of the storage battery is reduced and power can be supplied by the engine, in particular, when the commercial power supply is lost several times due to a large disaster etc. Met.

Unexamined-Japanese-Patent No. 5-207684 Unexamined-Japanese-Patent No. 2001-45681

  The problem to be solved by the present invention (technical problem or purpose, etc.) is not a large-scale emergency power generator, but a compact that easily supplies power not only for home use but also to traffic lights, various signs, surveillance cameras, etc. Provide an emergency power supply device. Moreover, in the event of a power failure, AC power of the same voltage and frequency as the main power supply can be supplied without interruption, and supply can be continued for 3 days. It is to realize that if you lose it, you can cope with it enough.

  Then, as a result of the inventor's earnestly researching to solve the above-mentioned subject, the invention of claim 1 is a small LPG gas engine with a displacement of 50 cc to 500 cc and a direct current generated by starting the gas engine. A generator, a storage battery for a power source, a battery for an engine, a plurality of on / off switches, and an integrated control unit for controlling the on / off switches, wherein a cylinder of the gas engine is viewed planarly; An ignition plug, an intake valve, the ignition plug, and an exhaust valve are disposed around the circumference, and intake air from the intake valve flows tangentially or in a direction close to a tangential direction in plan view of the cylinder. Under normal conditions, the power supply side of the commercial power supply is energized through the on / off switch, and the commercial power supply is turned off due to any accident or the like. At the moment of loss, AC power of the same frequency is supplied from the storage battery via the inverter to the power supply side at the same voltage as the commercial power supply and the battery for the engine from the moment the commercial power is lost Starting the gas engine having the configuration described above and generating power with the DC power generator by the driving force, and supplying the power from the storage battery when the gas engine generating power reaches a predetermined number of revolutions While supplying power to the power supply side with DC power generated by the gas engine, and continuing to supply power with only the gas engine until the commercial power is restored. The problem is solved by the power supply device.

  According to the invention of claim 2, in the simplified type emergency power supply device according to claim 1, the storage battery and the battery for an engine according to either the electric power by the gas engine at the time of the accident or the electric power at a normal time The above-described problem is solved by providing a simple type emergency power supply device characterized by providing a charging action to the above. According to the invention of claim 3, in the simplified emergency power supply device according to claim 1 or 2, the intake valve, the first spark plug, the exhaust valve and the second spark plug of the gas engine The above problem is solved by the simple type emergency power supply device characterized in that it is arranged in four equal parts. According to a fourth aspect of the present invention, in the simplified emergency power supply device according to the first, second or third aspect, the main stream of the air-fuel mixture flowing into the cylinder of the gas engine does not directly strike the ignition point of the spark plug. The present invention solves the above-mentioned problems by providing a simple type emergency power supply device characterized in that it is configured to flow in the vicinity thereof.

  According to the invention of claim 5, in the simplified type emergency power supply device according to claim 4, the lower surface of the flat spherical concave surface is formed while the lower surface of the cylinder head above the cylinder of the gas engine is formed into a flat spherical concave surface. And the bulging portion is provided on the front side of one of the spark plugs and on the downstream side of the air-fuel mixture, as a simplified emergency power supply device characterized in that I solved the problem. According to the invention of claim 6, in the simplified emergency power supply device according to claim 1, 2, 3, 4 or 5, a flywheel is provided between the gas engine and the direct current generator. The above-mentioned subject was solved by setting it as a simple type emergency power supply device characterized by the above. The invention of claim 7 is characterized in that, in the simplified emergency power supply device according to claims 1, 2, 3, 4, 5 or 6, the on / off switch is an on / off relay switch. The problem is solved by the simplified emergency power supply device.

  According to the invention of claim 1, the present invention can cope well even when the commercial power is lost a plurality of times due to a large disaster or the like. This is because electricity can be stored by the gas engine even during a power failure. Also, by using the storage battery only at the moment of a power failure, the mass is reduced to 1/350 or less, and control from the storage battery is switched to the power generated by the engine under control by a simple on / off switch. In order to supplement the electrical energy consumed earlier in the department, there is an advantage that it can sufficiently cope with repeated blackouts.

  Furthermore, according to the inventions of claims 1 and 2, the rotational inertia energy is increased even if the output is not easily able to follow the disadvantageous rapid increase in load because of the small engine, and this is converted into electric energy to supply stable power. At the same time, the storage battery terminal voltage and the generated alternating current are converted to direct current, and the same voltage is used to prevent a voltage drop in a very short time. In addition, the effect of LPG exists anywhere in Japan, enabling extremely efficient support and restoration in the event of an emergency.

  In the inventions of claims 3 to 5, in particular, the combustion efficiency can be increased, and the start-up of the gas engine can be improved. According to the invention of claim 6, it is possible to prevent the gas engine from being stalled. According to the seventh aspect of the invention, the relay device can be provided at low cost with a simple configuration.

It is a block diagram of 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 electric power from the emergency storage battery of this invention of the moment the supply from a main power supply was interrupted. It is a block diagram of a state when the gas engine is operating and power is stably supplied from the DC generator in an emergency. It is a simple flowchart figure which shows the operation state of this invention. It is a chart showing the flow of the present invention. It is a chart showing typically a response state to a sudden increase of electric load. It is a graph which shows the control characteristic of the throttle opening of sudden increase of an electrical load. (A) is a plan view of a single-cylinder portion, (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 line Y2-Y2 in (A) is there. It is an expansion state perspective view which shows the partial cross section of a single cylinder location.

  BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an embodiment of the present invention will be described based on the drawings, and FIGS. 1 to 3 are state diagrams showing the configuration and operation of the present invention. FIG. 1 is a block diagram of a normal state, and FIGS. 2 and 3 are operation state diagrams of an emergency. In these figures, two wires are required for single-phase alternating current and direct current, and three wires are required for three-phase alternating current, but the connection relationship is represented by a single wire for the sake of clarity. I will express it.

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

  Here, although the general control unit (TCU) 61 and the engine control unit (ECU) 62 cooperate with each other, function sharing will be described. The integrated control unit (TCU) 61 monitors the loss of the commercial power and sends an ON / OFF switch ON / OFF signal to the engine control unit (ECU) 62 to start and stop the gas engine 1. In addition to this, control of the electric output system such as control of the excitation current of the DC generator 3 described in FIG. 3 is performed.

  On the other hand, the engine control unit (ECU) 62 performs fuel supply to the gas engine, ignition timing and throttle opening / closing control, start / stop of the gas engine 1, water temperature control and the like. The electric power of the general control unit (TCU) 61 is supplied from the same low voltage engine battery 52 as the engine control unit (ECU) 62. If an emergency high-voltage storage battery 51 is used for this, two types of control power sources are used and this is to be avoided.

  In FIG. 1, it is an electric power generating apparatus provided with the gas engine 1, the fuel supply apparatus 2, and the direct current generator 3, and the gas cylinder 29 for liquefied petroleum gas (LPG) is used as a fuel. The gas engine 1 has a small displacement of about 50 cc to about 500 cc or less because it is a compact emergency power supply. The gas engine 1 is a multipoint ignition engine in which two spark plugs are disposed in one cylinder. This increases the opportunity for ignition and realizes rapid combustion to improve the thermal efficiency (fuel efficiency).

  The gas engine 1 is provided with a cylinder head 12 at the upper part of a cylinder 11 in which a piston 10 is accommodated so as to be able to move vertically, and the lower surface of the cylinder head 12 is formed as a flat spherical concave 12a. As viewed from above the upper surface side of the cylinder head 12 (or the cylinder 11), two spark plugs 13, an intake valve 15, and an exhaust valve 17 are provided. The intake valve 15, the spark plug 13, the exhaust valve 17 and the spark plug 13 are circumferentially divided into four equal parts (see FIG. 8A).

  The 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. Furthermore, the central axis m of the two spark plugs 13 and the central axis w of the intake valve 15 and the central axis u of the exhaust valve 17 are also configured to pass above the point P, respectively. In other words, the central axis m of the spark plug 13 and the central axis w of the intake valve 15 (the inlet of the intake port 14) and the central axis u of the exhaust valve 17 (the outlet of the exhaust port 16) also have a radius of curvature R. It exists on the normal of the spherical surface of the flat spherical concave surface 12a. Such a three-dimensional combustion chamber is configured [see FIG. 8 (B)].

  In particular, in the intake port 14 for intake to the intake valve 15, the intake air from the intake valve 15 flows into the cylinder 11 from a tangential direction or a direction approximate to a tangential direction when the cylinder 11 is viewed in a plan view. It is comprised so that it may become (Swirl G). When the piston 10 in the cylinder 11 is lowered, the swirl S (vortex) is generated (see FIG. 8 (B) and FIG. 9).

  Even in the case of the swirl S (vortex), directionality may be ensured. In order to ensure sufficient directionality, the following configuration is often used. In particular, on the lower side surface of the flat spherical concave surface 12a, a bulging portion 12b having a substantially crescent shape or trapezoidal mountain shape or the like is on the front side of one spark plug 13 and downstream of the swirl S (vortex). It is provided to be on the side. If the contents of the swirl S (vortex) are described in detail, the mainstream of the swirl S (vortex) does not strike the ignition point of the spark plug 13 and flows in the vicinity [FIG. 8 (A) reference〕.

  The bulging portion 12b has a substantially crescent shape, and a longitudinal cross section has a substantially triangular shape (see FIGS. 8A and 8B), and functions to change the flow of the swirl S (vortex). Yes, the highest height may be around 1 mm. The swirl S (vortex) can cause a small turbulent flow also at the bulging portion 12b. Further, even if the bulging portion 12b has a trapezoidal mountain shape in which Mt. Fuji is flattened or the trapezoidal mountain shape is formed in half (vertically divided) (not shown), it is similar to the bulging portion 12b of the crescent moon type described above. Play the effect of The bulging portion 12b is not limited to the shape as long as the directionality of the swirl S (vortex) can be changed.

  Further, in FIGS. 8A and 8B, it is preferable that the flow rate of the main flow to the counter main flow be about 8 to 2. Due to the presence of the anti-mainstream, turbulence in the air flow may occur to improve mixing as well as to promote better gas (LPG) combustion. Such an arrangement is a great advantage not present in the prior art. In particular, as shown in FIG. 9, the main flow in the swirl S (vortex) is such that it receives a counterflow in the cylinder 11 and gradually slows down and at the same time exhibits a fine turbulent state. It is possible to combine gas air with LPG gas.

  Temporarily, if the main stream of strong swirl S (vortex) strikes the ignition point (spark gap) of the spark plug 13, the temperature of this part falls (for example, 450 ° C. or less), free carbon is generated, and the tip is tainted. As a result, it is difficult for the sparks to fly, but a new mixture is made to flow into the spark gap while avoiding a direct hit of the tip. Once the flame is ignited, the flame extremely rapidly spreads three-dimensionally in the combustion space (the entire space defined by the cylinder head 12 and the inner wall surface of the cylinder 11 and the top surface of the piston 10) by the swirl S (vortex). The combustion efficiency of the gas can be significantly increased.

The combustion efficiency is extremely good because 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 are extremely good. Play an effect. Furthermore, the start of the gas engine 1 immediately after a power failure also has the greatest advantage that it can be started very early.
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 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 about 12 ° to about 14 ° (see FIG. 8B).

  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 is in the venturi 19a of the mixer 19 connected to the intake duct 18 in front of the intake port 12. It is comprised so that it may connect. The LPG flows into the intake port 12 through the solenoid valve 27 and the pressure control valve 26 in the gas pipe 25. Finally, the throttle 20 is opened by the throttle actuator 21 as appropriate, and the gas is ejected. That is, as shown in FIG. 1 and FIG. 9, the fuel supply device 2 includes the throttle 20, the throttle actuator 21, the gas pipe 25, the pressure regulating valve 26, the solenoid valve 27, the pressure reducing valve 28, the gas cylinder 29 and the like. It is configured.

  Further, the fuel (LPG) is depressurized to near atmospheric pressure by the pressure control valve 26, metered by the orifice 25a, and led to the fuel passage in the mixer 19. The air is adjusted by the slit step hole 22 of the venturi 19 a and the idle mixture screw 23 and mixed with the air taken in from the downstream of the throttle 20. Fuel is supplied from the downstream of the throttle 20 at idling and from the slit step hole 22 mainly at transient time or low speed. When the required output of the gas engine 1 is increased, the suction of fuel from the slit of the venturi 19a is dominant.

  As described above, the fuel is liquefied petroleum gas (LPG) which is easy to obtain, is filled in the gas cylinder 29, and is convenient for transportation. The LPG has the advantage that it does not deteriorate even as it is stored for a long time, like gasoline and diesel oil. Furthermore, it has advantages of shorter start-up time and less carbon dioxide and nitrogen oxide emissions than conventional diesel fueled diesel fuel engines. As shown in FIG. 1, in the figure, 44 is a radiator and 45 is a fan motor.

  A direct current 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. It takes about 10 seconds to about 40 seconds for the gas engine 1 to start and for stable power to be supplied from the direct current generator 3. Assuming that the power output from the junction point P2 is 1 kW, the power covering this interval is 1 kJ / s × 40 s = 40 kJ at the maximum. However, if the conversion efficiency to make the predetermined alternating current in the inverter 71 is 93%, then 40 kJ / 0.93 = 43 kJ.

  When the storage battery 51 is a general lithium ion battery, this energy density is about 360 kJ / kg, so (43 kj) / (360 kJ / kg) = 0.12 kg is sufficient to store 43 kj of electrical energy. Become. However, the battery has power density (W / kg) as well as energy density (kJ / kg). In the case of a lithium ion battery, this is about 700 W / kg, so (1.08 kW) / (0.7 kW / kg) ≒ 1.6 kg is required to output 1 kW / 0.93 = 1.08 kW.

  The mass of the battery that simultaneously meets the energy density and the power density is 1.6 kg or more. Where the separation is good, as much as 2 kg can supply sufficient power until the power generation by the engine is stabilized. As described above, the supply time of the electrical energy from the storage battery 51 is until the gas engine 1 of the direct current generator 3 starts up, and the power supply time is short. In order to further shorten it, it is essential to shorten the start-up time of the gas engine 1.

  Further, during the day of FIG. 1, the battery 52 for engine is converted into a direct current of low voltage (for example, 12 V) by an alternating current → direct current inverter 74 to perform a charging operation (see a broken line). Further, the battery 51 for emergency is also charged via the AC to DC inverter 71 (see a broken line). The engine battery 52 is, for example, a 12 V lead / dilute sulfuric acid battery for automobiles, and the storage battery 51 is often a lithium ion battery, a lithium ion capacitor, a nickel hydrogen battery or the like with a full charge control function. .

  In the state of FIG. 1, since the power from the storage battery 51 and the DC generator 3 is not used, the on / off switches 82 and 85 of this circuit (the storage battery 51 and the DC generator 3 from the commercial power output side) maintain the open position. It remains as it is. The state of the commercial power supply (whether electricity is coming or not) is determined by the voltage applied to the general control unit (TCU) 612 from the junction point P1 through the fixed resistor 91 through the main power supply signal line 90. This is because the integrated control unit (TCU) 61 can determine whether a power failure has occurred with a weak current due to the presence of the fixed resistor 91. If there is also a resistor in the general control unit (TCU) 61 and the voltages before and after this are monitored, this voltage will be zero if the main power supply (commercial power supply) is lost.

  In normal times, as shown in FIG. 1, the on / off switch 83 is closed, and power from the main power supply is output from the junction point P1 through the junction point P2 as indicated by a thick arrow. The on / off switch 83 has a function of turning on / off a circuit by a signal from the total control unit (TCU) 61. The switch may open and close the contact electromagnetically, or may be a normal noncontact switch using a transistor.

Next, a description of the operation in an emergency will be described based on FIG. 2 and FIG.
When it is detected that the commercial power is lost due to some accident or the like, the on / off switches 81 and 83 are opened by the operation of the general control unit (TCU) 61 in FIG. 1, and the on / off switch 82, 85 closes. At this time, if a time constant is provided to the output signal of the general control unit (TCU) 61 and the closing time is delayed by several ms, a possible short circuit can be avoided.

  The on / off states of the aforementioned on / off switches 82, 85, 81, and 83 are instantaneous, and these become the state of FIG. 2 (emergency time: transient period). That is, at the moment when the commercial power is lost due to some accident or the like, AC power of the same frequency as that of the commercial power at an emergency by way of the inverter 71 via the junction point P4 from the storage battery 51 for emergency Are supplied to the power supply side via the junction point P2.

  That is, at the moment when the commercial power is lost, the power stored in the storage battery 51 for emergency becomes the same voltage and frequency as the main power at the DC → AC inverter 71 from the junction point P4 as shown by the arrow. And the junction point P2 to the power supply side. In FIG. 1 to FIG. 3, solid arrows indicate the direction of power output, and dotted arrows indicate the state of charge operation.

  Also, when the on / off switch 83 is opened, the power from the storage battery 51 flows through P2 to the integrated control unit (TCU) 61, and the integrated control unit (TCU) 61 erroneously recognizes that the main power supply is restored. Do not. Similarly, the on / off switch 83 is also opened to prevent backflow. Although the power is still small, it is converted to a direct current again from the junction point P 2 through the power conditioner 74 and charged to the engine battery 52. In particular, it can provide a charging action even in an emergency.

  Next, the features of the present invention when power is generated by the gas engine 1 and power supply is continued in earnest over a long time in FIG. 3 will be described. Before that, the process until the gas engine 1 is started Describe. First, when the integrated control unit (TCU) 61 detects the loss of the commercial power (main power), the signal is transmitted from the integrated 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 (12 V) 52. At the same time, a signal from the engine control unit (ECU) 62 is energized to open the solenoid valve 27 which shuts off the gas coming from the gas cylinder 29 (for LPG) via the mechanical pressure reducing valve 28 normally used.

  At the same time, the pressure control valve 26 for adjusting the pressure of the fuel at almost atmospheric pressure is operated to be ready to supply the fuel to the fuel supply device 2 of the gas engine 1. On the other hand, the supply of engine oil which is essential for the operation of the gas engine 1 is 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 by the negative pressure generated by suction, compressed, ignited and started. This startability is far 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 up and reaches the rated speed and power can be supplied from the DC generator 3 rotating at the same speed, the on / off switch is turned off as shown in FIG. 2 from FIG. It changes. 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 rotation sensor 48. The degree of opening of the throttle 20 of the fuel supply device 2 is adjusted by the signal of the engine control unit (ECU) 62 so that this becomes a predetermined rotation speed, for example, 2000 rpm.

  The on / off switch 83 remains open but the on / off switches 85 and 82 are closed. The direct current generated by the direct current generator 3 is the same as that supplied from the storage battery 51 of FIG. 2 from the junction point P4 as indicated by the arrow in FIG. And the alternating current of the frequency, and output from the junction point P2 through the on / off switch 82. At this time, the direct current power of the direct current generator 3 by the gas engine 1 is supplied from the junction point P4 to the storage battery 51 for charging.

  As a result, the electric energy of the storage battery 51 reduced by the previous discharge is replenished to the full charge. This emergency charging function is a great advantage. This is to prepare when the main power is restored and lost. Similarly, it is configured to be converted into low voltage direct current by the power conditioner 74 and to charge the engine battery 52 as well.

  When the coolant temperature rises while the gas engine 1 is operating, the thermostat 43 opens and the coolant circulates through the radiator 44. Further, when the water temperature rises, the fan motor 45 is energized to promote the heat radiation from the radiator 44 by the cooling air.

Next, the consumption of fuel and the energy generated therefrom will be described. As an example, it is assumed that the gas cylinder 29 is filled with 20 kg of propane C ₃ H ₈ . The molecular weight of C ₃ H ₈ is 44, ie 1 mole, and the mass of 22.4 liters under standard conditions (0 ° C., 1 atm) is 44. On the other hand, the low calorific value (hereinafter abbreviated as calorific value) of propane in a 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). Find the electric energy that can generate electricity with only this amount of heat, and examine whether it can supply 1 kW for 72 hours.

The thermal efficiency obtained for a low speed, low speed rotating multipoint ignition engine with low friction losses is 36%. The efficiency of the generator is 95%, and the conversion efficiency of the direct current to alternating current inverter 71 is 93%. Further, the energy consumed by the engine is (1 kJ / s) / (0.36 × 0.95 × 0.93) = 3.1441 kJ / s assuming that the output from the junction point P2 continues to produce the maximum 1 kW. The time to consume 923 × 10 ³ kJ is (923 × 10 ³ kJ) / (3.144 kJ / s) ≒ 294000 s, or 75.8 hours. One 20 kg cylinder can generate electricity for 81 hours or more, and the target 72 hours can be achieved with time.

  When the commercial power supply (main power supply) recovers, the integrated control unit (TCU) 61 detects it, opens the on / off switches 82 and 85, closes the on / off switch 83, and joins from the junction point P1. The power of the main power supply is supplied to 2. Further, the engine control unit (ECU) 62 shuts off the solenoid valve 27 at the same time as stopping the engine to shut off the fuel. And it returns to the state of FIG.

  Here, the switching speed of each on / off switch is at most 10 ms. On the other hand, it is 1/16 second which is the afterimage time of a healthy human eye, that is, 62.5 ms. This means that a momentary blackout can not be noticed by human eyes. When the gas engine 1 is rotating at a rated rotational speed at a power lower than a predetermined power, it is assumed that the required electrical power suddenly increases. As the load increases, the engine speed decreases. Although the throttle of the fuel supply device 2 is opened by a signal from the engine control unit (ECU) 62 in order to recover this, it takes a short time before returning to a predetermined rotational speed.

  A small engine with small output capacity can not counteract this, and the output voltage at the junction point P2 may decrease, or the gas engine 1 may stop in an extreme case. On the other hand, although the power release from the storage battery 51 is also effective temporarily, it is also necessary to be able to cope with the rapid increase of the load by the gas engine itself even for a small engine. The flywheel 9 may be provided as such a means.

  As its structure, as shown in FIG. 1 to FIG. 3, a flywheel 9 having a thick outer peripheral portion on the outer periphery is fixed to an end of a crankshaft of the gas engine 1 by a fastening bolt. Further, a male spline 35 provided at the center of the DC generator 3 is fitted and fixed to a female spline in a boss formed at a central position of the flywheel 9. It is mounted in a very simple configuration.

When the rotational inertia moment Ip (unit: kgm ² ) is large, the decrease in rotation becomes gentle. The engine speed immediately after the entry is higher than that of the conventional type. If it is high, since the number of times of suction is large, the time from the mixer to filling the cylinder 1 becomes short. Then, the amount of mixture supplied during that time increases. A lot of thermal energy is generated, that is, it blows up vigorously. 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.

  Further, comparing the graph of the present invention provided with the flywheel 9 with the prior art, in the prior art, when a sudden electrical load is generated in the gas engine 1 at the time of emergency, the engine rotational speed decreases and the engine stalls The rise falls to the limit and converges (converges), but is slow, and the convergence (convergence) time according to the start-up of the present invention is about half, and there is an advantage that the configuration can be made extremely difficult to stall.

  As the DC generator 3, a commutator 32 is provided on a rotor 31 directly connected to the flywheel 9 from the gas engine 1, and a brush 34 is attached to the commutator 32 so as to be in contact therewith. The rotor 31 is provided with a stator coil 33. As a result, the rotor 28 of the DC generator rotates at the same speed as the rotation of the gas engine 1. The control of the power to be generated is performed by the excitation current supplied from the brush 34 to the commutator 32 and the rotor 31.

  The integrated control unit (TCU) 61 supplies an excitation current to the rotor 31 while controlling the excitation current with the power supplied from the engine control unit (ECU) 62. As a result, power of a predetermined voltage is generated in the stator coil 33. The DC power from the stator coil 33 passes through the on / off switch 85 and becomes parallel to the power of the storage battery 51 at the junction point P4 and is converted into an AC of the same voltage and frequency as the commercial power by the DC → AC inverter 71. Output from the junction point P2 via the off switch 82.

  Here, if the electrical load is large, the required torque of the gas engine 1 increases and the rotational speed decreases, so the throttle actuator 21 is operated by the signal from the engine control unit (ECU) 62 to increase the opening degree of the throttle 20. It is made to maintain at a predetermined number of revolutions. If the number of revolutions is too high, the reverse control is performed.

  A countermeasure is shown in FIG. 6 in the case where the energy of the rotation of the flywheel 9 alone is insufficient for the sudden increase of the electrical load. As shown in the lower graph, when the electric load suddenly increases from L1 to L2, the voltage at the junction point P4 drops from Ec only by the power generation by the gas engine 1. Then, the rotational speed of the gas engine 1 is also greatly reduced from the predetermined rotational speed Ne (for example, 2000 rpm). Here, while the rotational speed of the gas engine 1 is maintained at a predetermined value, it means that the electric load is supplied with balanced power.

  As described above, when the rotation speed of the gas engine 1 starts to decrease, the output side of the DC generator 3 and the terminal of the storage battery 51 are connected in parallel, so the generated voltage is higher than the terminal voltage of the storage battery 51 (for example, 96 V) When it decreases, DC power is automatically supplied from the storage battery 51 to the DC → AC inverter 71. As a result, the output voltage can maintain the predetermined AC voltage E as shown in the upper graph of FIG. 6, but of these, the junction point P2 part is due to the power from the storage battery 51. The electric energy of the storage battery 51 due to the discharge is charged after the gas engine 1 returns to the steady operation state.

  Note that when the gas engine blows up slowly and the voltage generated by the generator is lower than the voltage of the storage battery 51, if the potential difference is large, backflow from the storage battery 51 to the DC generator 3 may occur. In order to prevent this, a backflow breaker in the direction of the stator coil 33 is inserted between the stator coil 33 and the on / off switch 85 or between the on / off switch 85 and the junction point P4.

  Since the throttle 20 increases the opening degree in response to a signal from the engine control unit (ECU) 62 simultaneously with the supply of electric power from the storage battery 51, the rotational speed of the gas engine 1 reaches a predetermined rotational speed Ne. However, as it is, the generated voltage further rises, the generated voltage exceeds a predetermined value, and a runaway state may occur.

  Therefore, the throttle opening control described in FIG. 7 is performed. As shown in the lower part, when the electric load increases from L1 to L2 at time T, the throttle opening is changed from the throttle opening β1 which has maintained the predetermined gas engine rotational speed at L1 immediately as in the middle part. Then, as shown in the upper row, the gas engine rotational speed once lowered to (1) starts to rise.

  Then, at (2), the rotation speed reaches a predetermined rotation speed Ne. Therefore, as in the middle stage, the throttle opening is gradually closed by 5% per second, for example, or 5% stepwise every one second. As a result, the rise in gas engine speed slows down and falls. At the moment when it reaches Ne in (2), it gradually opens 4% per second or 4% per step. And when it reaches (4) it closes 3% each. If this is repeated, it converges to the throttle opening which maintains predetermined | prescribed rotation speed (for example, 1800 rpm). Needless to say, it may be changed depending on the actual situation instead of 5% or 4%.

  When the electric load gradually increases, the rotational speed of the gas engine 1 gradually decreases, so engine control is performed so that the rotational speed detected by the crank rotational sensor 48 maintains a predetermined rotational speed without suddenly being full throttle. The throttle 20 is opened by a signal from the unit (ECU) 62. Conversely, when the rotational speed of the gas engine 1 gradually increases, a signal from the engine control unit (ECU) 62 is set so that the rotational speed detected by the crank rotation sensor 48 maintains a predetermined rotational speed. And the throttle 20 is closed.

  When the integrated control unit (TCU) 61 detects the return of the commercial power supply, the integrated control unit (TCU) 61 sends a signal for stopping the gas engine 1 to the engine control unit (ECU) 62 and turns on the emergency power system. • Turn off the off switches 85 and 82 and turn on the on / off switches 81 and 83 at the same time. On the other hand, the engine control unit (ECU) 62 cuts off the ignition, and the throttle actuator 21 closes the throttle 20, and the electromagnetic valve 27 also closes. Thus, the commercial power source passes through the device from the junction point P1 and is output from the junction point P2. Even if the ignition cut is delayed for a moment due to some reasons, if the rotational inertia moment of the flywheel 9 is set large as described above, the rotation will be too high and the gas engine will not be destroyed.

  Each of the on / off switches 81, 82, 83 and 85 may be configured as an on / off relay switch. These relay switches are ordinary noncontact switches using a semiconductor even if the contacts are opened and closed electromagnetically. Mainly due to economics. Also, the flow chart of FIG. 4 represents the basic steps of the present invention. Furthermore, in the table of FIG. 5, in particular, the features of the invention are represented.

  That is, even if power failure and recovery continue at predetermined time intervals (from 1 day to 3 days, etc.) as in the lowermost stage, it is configured to charge the storage battery 51 etc. for emergency even in an emergency. by. Such a configuration is the greatest advantage that has not existed in the prior art. For example, it is an invention that can sufficiently cope with the case where the seismic intensity 7 continues twice within 24 hours in the recent Great Kumamoto Earthquake.

  In general, when the throttle 20 which is a known technique is appropriately opened, the LPG flows into the intake duct 18 from the orifice 18a, but as if tap water simply flows in, the LPG is also a gas, Air is a situation where mixing is difficult, and as described above, the mixture of LPG and air is well mixed with air and LPG due to the swirl S phenomenon or the like in the cylinder 11 described above. Thus, the gas engine 1 with good combustion efficiency can be provided.

1 ... gas engine, 11 ... cylinder, 12 ... cylinder head, 13 ... spark plug,
15: Intake valve, 17: Exhaust valve, 12a: Flat spherical concave surface, 12b: bulging portion,
DESCRIPTION OF SYMBOLS 2 ... Fuel supply apparatus, 3 ... DC generator, 51 ... Storage battery, 52 ... Battery for engines,
61 ... integrated control unit (TCU),
81, 82, 83, 85 ... on-off switch, 9 ... flywheel.

  Then, as a result of the inventor's earnestly researching to solve the above-mentioned subject, the invention of claim 1 is a small LPG gas engine with a displacement of 50 cc to 500 cc and a direct current generated by starting the gas engine. A generator, a storage battery for a power source, a battery for an engine, a plurality of on / off switches, and a general control unit for controlling the on / off switches, wherein two spark plugs are provided in a cylinder of the gas engine And the first spark plug, the intake valve, the second spark plug, and the exhaust valve are disposed circumferentially, and the intake air from the intake valve flows in the cylinder. In plan view, it is configured to flow in a tangential direction or a direction approximating a tangential line, and under normal conditions, the power supply of the commercial power supply is made via the on / off switch. The power supply side is turned on, and at the moment when the commercial power is lost due to some accident etc., the storage battery temporarily supplies AC power of the same frequency as the commercial power via the inverter from the storage battery via the inverter. The electric power is supplied to the power source, and the gas engine with the above-described configuration is started with the battery for the engine from the moment the commercial power source is lost, and the DC generator generates electric power with the starting power to generate the gas When the engine reaches a predetermined rotational speed, the supply of power from the storage battery is stopped, and at the same time the DC power generated by the gas engine is supplied to the power supply side, and only the gas engine is restored until the commercial power is restored. The above-mentioned subject was solved by setting it as a simple type emergency power supply device characterized by continuing feeding by the electric power of the above.

Claims (7)

A small LPG gas engine with a displacement of 50 cc to 500 cc, a DC generator that generates electricity by starting the gas engine, a storage battery for power supply, a battery for the engine, a plurality of on / off switches, the on / off switch And an integrated control unit that controls the off switch,
In a plan view of the cylinder of the gas engine, an ignition plug, an intake valve, the spark plug, and an exhaust valve are disposed circumferentially, and an intake air from the intake valve looks in a plan view in the cylinder; Configured to flow in a tangential direction or a direction approximating to the tangent,
Under normal conditions, the power supply side of the commercial power supply is energized through the on / off switch, and the commercial battery is temporarily interrupted from the storage battery through the inverter at the moment when the commercial power is lost due to an accident or the like. The AC power of the same frequency as that of the power supply is supplied to the power supply side, and the gas engine having the above-described configuration is started with the battery for the engine from the moment the commercial power is lost to start the power Generate electricity by the DC generator,
When the gas engine being generated reaches a predetermined rotational speed, the supply of power from the storage battery is stopped, and at the same time, the DC power generated by the gas engine is supplied to the power supply side, and the commercial power is restored A simple type emergency power supply device characterized in that power supply is continued with power of only the gas engine until time.   The simplified emergency power supply device according to claim 1, wherein the storage battery and the battery for the engine are charged even if the power from the gas engine at the time of the accident or the power at the normal time is used. A simplified emergency power supply device characterized by:   The simplified emergency power supply device according to claim 1 or 2, wherein the intake valve, the first spark plug, the exhaust valve and the second spark plug of the gas engine are equally divided into four parts. Simple emergency power supply device characterized by becoming.   4. The simplified emergency power supply device according to claim 1, 2 or 3, wherein the main flow of the air-fuel mixture flowing into the cylinder of the gas engine does not strike the ignition point of the spark plug directly and flows in the vicinity thereof. What is claimed is: 1. A simplified emergency power supply device comprising:   5. The simple type emergency power supply device according to claim 4, wherein the lower surface of the cylinder head at the upper portion of the cylinder of the gas engine is formed into a flat spherical concave, and a bulging portion is formed on the lower side of the flat spherical concave. A simple type emergency power supply device characterized in that it is provided on the front side of each spark plug and on the downstream side of the air-fuel mixture.   The simple type emergency power supply device according to claim 1, 2, 3, 4 or 5, wherein a flywheel is provided between the gas engine and the DC generator. Power supply equipment.   The simplified emergency power supply device according to claim 1, 2, 3, 4, 5 or 6, wherein the on / off switch is an on / off relay switch. .

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