JP4859707B2 - Cogeneration apparatus and wiring confirmation method for current detection means in the cogeneration apparatus - Google Patents

Description

  The present invention relates to a cogeneration apparatus and a wiring confirmation method for current detection means in the cogeneration apparatus, and in particular, is connected to an external power source and a power usage apparatus to consume power generation means and surplus power of the power generation means. A surplus power consuming means; and a current detecting means for detecting a current amount of the external power source and consuming surplus power of the power generating means by the surplus power consuming means to prevent reverse power flow, and wiring connection of the current detecting means The present invention relates to a cogeneration apparatus and a wiring confirmation method for current detection means in the cogeneration apparatus, which can accurately check the situation.

  Recent cogeneration systems use a relatively clean energy engine, such as natural gas, to drive the generator. When operating at a low output, the efficiency decreases, so when operating it operates at a rating of, for example, 1 kW. In response to the fluctuations in the load of the power usage device in the home, power supply and hot water supply can be performed while connecting to the commercial system.

  Such a cogeneration device is disclosed in, for example, Patent Document 1, in which a current sensor is provided in a commercial system, a power storage device and a surplus power consumption heater are provided on the power usage device side, and a current amount of the commercial system is detected by the current sensor. For the hot water supply, the power is stored in the power storage means and the surplus power consumption heater is operated so that the surplus power of the generator does not flow backward to the commercial system when the power used by the power generator is small. A cogeneration device is shown that is capable of heating.

  This will be briefly described with reference to FIG. 4. In the figure, 50A, 50B, 50C,... Are power consuming devices provided at power consuming locations such as ordinary households, and 52 generates heat and power as power generation means. This is a combined heat and power supply device that supplies power to the power consuming device 50, and includes a generator 52g and a gas engine 52e that drives the generator 52g, and is configured to generate AC power. 53 is an operation control unit for controlling the operation of the cogeneration system, 54 is an inverter for setting the output power of the generator 52g to the same voltage and frequency as the power supplied from the commercial system 60, and 55 is a plurality of power consuming devices 50. A storage battery 56 is provided in some of the power consuming devices 50 to prevent the surplus power generated by the generator 52g from flowing back to the commercial system 60 and to store the power consumed by itself. It is a charge / discharge control unit that performs control to store electric power in the storage battery 55 or to discharge the electric power from the storage battery 55.

  57 is an electric heater that warms water using this surplus power when the electric power generated by the combined heat and power supply device 52 cannot be used even by charging the power consuming devices 50A, 50B, 50C,. For example, a heater that consumes about the same power as the output power 1 KW of the generator 52 g is used. 58 is a direct current power supply unit that converts alternating current to direct current in order to store surplus power in the storage battery 55, 59 is a charge intermittent switch that switches between a charged state of the storage battery 55 and an operating state that consumes the stored power, and 60 is an external power supply As a commercial system, 61 is a distribution board provided in the home, 62 is a commercial line, 63 is a power supply line, 64 is a current flowing through the commercial line 62, and detects whether a reverse power flow occurs. A current sensor, 65 is a heater distribution line, 66 is a switching circuit for adjusting electric power supplied to the electric heater 57, 67 is a cooling water circulation path, and 68 is a cooling water circulation pump. Although not shown, the hot water heated by the gas engine 52e and the electric heater 57 through the cooling water circulation path 67 is stored in a hot water storage tank or the like, supplied to a heating terminal or the like, and used for indoor heating or the like. The

  In this cogeneration system, the electric power generated by the generator 52g driven by the gas engine 52e is aligned by the grid interconnection inverter 54 so that the voltage and frequency are the same as those of the commercial system 60, and the feed line 63 Sent out. On the other hand, the exhaust heat of the gas engine 52e warms the cooling water sent from the cooling water circulation pump 68 through the cooling water circulation path 67, and is also generated by the generator 52g to generate power consumption devices 50A, 50B, 50C,. It is heated by an electric heater 57 that is driven by surplus electric power that has not been used up and is stored in a hot water storage tank (not shown) or supplied to a heating terminal or the like for indoor heating or the like.

  Then, the electric heater 57 is driven by surplus electric power when the operation control unit 53 receives a signal from the current sensor 64 that measures the current flowing through the commercial line 62 so that the generated power of the generator 52g does not flow backward to the commercial system 60 side. However, the switching circuit 66 is controlled to adjust the power supply.

  That is, when there is no surplus power in the combined heat and power supply device 52, a current from the commercial system 60 (hereinafter referred to as positive current) is detected through the current sensor 64, but when surplus power is generated in the combined heat and power supply device 52, the current sensor The positive current value of 64 is not detected. Therefore, the operation control unit 53 controls the switching circuit 66 so that when the forward current value detected by the current sensor 64 tends to decrease, the forward current value becomes the set lower limit current value for preventing reverse power flow. Is configured to do.

  Such a cogeneration system generally includes, for example, a hot water supply unit that uses waste heat from the cogeneration device 52 and the engine, and an operation control unit that controls the cogeneration device 52 and the hot water supply unit, for example, outside the cooking area. The current sensor 64 for detecting the current from the commercial system 60 is installed at the distribution board 61 in the home, so that the current sensor 64 is located around the cooking area. Wiring to the operation control unit 53 installed outside is required.

  Currently, 200V equipment is often used for high-power room air conditioners, heat-transfer dryers, and cooking heaters used at home, but commercial systems used for such cogeneration systems are also available. Generally, a single-phase three-wire 200V is used. For this reason, the wiring from the current sensor 64 to the operation control unit 53 in the power generation / hot water supply unit requires three wires corresponding to the three wires of the U phase, the N phase, and the V phase. Even though there is no surplus power, a reverse power flow may be erroneously detected, resulting in a failure to generate power.

JP 2006-158148 A

  For such a problem, for example, when the cogeneration apparatus is installed, for example, a breaker (not shown) provided in the cogeneration apparatus of Patent Document 1 shown in FIG. If the electric heater 57 for surplus power consumption is turned on with the three wires connected, the current of the current sensor 64 connected to the U phase and the V phase increases and decreases, so that the U phase and V phase are reversed. Can be confirmed. Whether only the U-phase or only the V-phase is connected and the electric heater 57 is turned on so that the current sequence of the current sensor 64 connected to each of the U-phase and V-phase is increased or decreased, so that the phase sequence is correctly connected. It can also be judged.

  However, it has been found that erroneous detection also occurs in the method of checking the wiring state of the current sensor 64 in this way. That is, when various loads are moving in the home, and the timing for turning on / off the load coincides with the timing for checking the wiring state of the current sensor 64, the current that should be increased decreases or decreases. There are cases where the correct current cannot be determined due to an increase in the expected current.

  For example, the toilet seat heater for washing toilets is about 1 KW, which is the same as the electric heater 57 for surplus power, but this toilet seat heater uses a semiconductor to perform PWM (Pulse Width Modulation) switching to keep the toilet seat temperature constant. It is said. In addition, the air conditioner also performs PWM control using an inverter, and a large current flows or stops each time the compressor of the refrigerator starts or stops. Therefore, the switching cycle of these loads coincides with the ON / OFF timing of the surplus power consumption electric heater 57 for checking the wiring state, or such a load is present after the surplus power consumption electric heater 57 is turned on. When the power is turned on or off, a phenomenon such as a decrease in current that should increase originally, an increase in current that should decrease, or repeated increase / decrease occurs, and correct determination cannot be made.

  In the cogeneration apparatus disclosed in Patent Document 1, the heater 57 for consuming surplus power is provided on the AC side. In this case, the heater 57 for consuming surplus power is provided for each of the U phase and the V phase. In order to consume surplus power finely, for example, a plurality of electric heaters 57 are provided step by step in increments of 100 W and the corresponding electric heater 57 is energized according to the surplus power amount. I need it. However, even in such a case, fine control of 100 W or less cannot be performed, and in order to do so, it is necessary to provide heaters in finer steps, leading to an increase in the number of parts and, consequently, an increase in cost. .

  Therefore, in the present invention, it is possible to accurately check the wiring state of the current sensor that detects the current of the commercial system with a simple and inexpensive configuration, and to consume surplus power corresponding to the amount of power. It is a problem to provide a cogeneration apparatus capable of performing the above and a method for confirming the wiring of current detection means in the cogeneration apparatus.

The cogeneration apparatus according to the present invention for solving the above problems is
A power generation unit connected to an external power source composed of a U phase, an N phase, and a V phase and a power usage device, the power generation unit, a power generation unit, a surplus power consumption unit that consumes surplus power of the power generation unit, And a control means for controlling the power generation means and the surplus power consumption means. The external power source is provided with a current detection means for measuring the currents in the U phase and the V phase . In the cogeneration apparatus that controls the surplus power consumption means to consume the surplus power generated by the power generation means based on the output,
The power generation unit includes power consumption variable means for changing a duty ratio by PWM (Pulse Width Modulation) control of the power consumption of the surplus power consumption means, and the control means supplies the power consumption variable means to an external power frequency. In addition, the surplus power consuming means is turned on / off at a small frequency, and the ON / OFF frequency of the surplus power consuming means is set according to the wiring state confirmation status of the current detecting means provided in the U phase and V phase of the external power source. Configured to change,
Further, the control means includes a current amount in each of the current detection means that changes with ON / OFF of the surplus power consumption means when the surplus power consumption means and the U phase and N phase of the external power source are connected. And, when the surplus power consumption means and the V phase and N phase of the external power source are connected, the U from the amount of current in each of the current detection means that changes with ON / OFF of the surplus power consumption means It has the function to confirm the wiring state of the current detection means provided in the phase and the V phase and the power generation unit.

  The power generation unit includes AC / DC conversion means for converting the output of the power generation means to DC, and DC / AC conversion means for converting the AC / DC conversion means output to AC, and the surplus power consumption means It is provided between the AC / DC conversion means and the DC / AC conversion means.

  Further, the power generation unit connects the U-phase, N-phase, and V-phase outputs in the output of the DC / AC conversion means simultaneously with an external power supply, and connects the U-phase with the external power supply. A second switch means and a third switch means for linking the V-phase with the external power supply, and the control means is configured to connect the U-phase and V-phase wirings when the first switch means is turned on. The normal / reverse confirmation is performed by confirming the wiring state of the U-phase and the V-phase by turning on the second and third switch means.

Moreover, the connection confirmation method of the current detection means in this cogeneration device is as follows:
Power usage device and the U-phase, N phase, comprising a power generating unit connected to an external power source consisting of V phase, prior to said power generation unit of each provided current sensing means and the U-phase and V-phase in Kigaibu power A wiring confirmation method for current detection means in a cogeneration device, wherein the wiring state is confirmed by energizing surplus power consumption means that consumes surplus power of the power generation means constituting the power generation unit,
The surplus power consumption means is turned on / off at a frequency smaller than the external power supply frequency in a state where the U-phase, N-phase, and V-phase in the power generation unit and the external power supply are linked, and the current detected by the current detection means A first step of determining the U-phase and V-phase wiring directions by increase / decrease, and the surplus power consuming means in a state where the surplus power consuming means and the U phase and N phase of the external power supply are connected to each other. Increase / decrease in current detected by each of the current detection means when ON / OFF at a smaller frequency, and the surplus power in a state where the surplus power consumption means and the V phase and N phase of the external power source are connected a second step of determining the correctness of the wiring phase order by increasing or decreasing the current detected by each of said current detecting means when the consumer means and ON / OFF at a smaller frequency than the external power source frequency The first step and one of the wiring direction and phase sequence errata in the second step, or if both of the confirmation could not, the ON / OFF frequency of the previous SL excess over - power means from said external power source frequency And the third step of performing the first and second steps, and
The wiring state of the current detection unit with the power generation unit is confirmed by changing a frequency for turning on / off the surplus power consumption unit.

  As described above, the surplus power consumption means is provided with the power consumption variable means for changing the power consumption by changing the duty ratio by PWM control, and the surplus power consumption means is provided at a frequency smaller than the external power supply frequency by the power consumption variable means. By turning on / off and changing the ON / OFF cycle of surplus power consumption means according to the wiring status confirmation status between the power generation unit and the current detection means provided in the U phase and V phase, for example in the home ON / OFF of the power usage device and surplus power consumption means by changing the ON / OFF cycle of the surplus power consumption means even if the power usage device of the power supply is turned ON / OFF and the wiring state cannot be confirmed successfully ON / OFF can be discriminated, and the wiring status check with the power generation unit of the current detection means can be performed accurately and accurately with a simple and inexpensive configuration. It can be. In addition, by allowing the power consumption of the surplus power consumption means to be changed by PWM control, it is possible to consume surplus power at the last minute that does not cause reverse power flow to the external power supply (commercial system). Electricity can be used effectively.

  And the surplus power consumption means is installed in the direct current portion between the alternating current direct current conversion means and the direct current alternating current conversion means constituting the power generation unit, thereby wiring between the power generation unit and the current detection means provided in the U phase and the V phase. When checking the state, it is necessary to rectify the external power supply and connect it to the surplus power consumption means. However, as in the conventional cogeneration apparatus described above, the surplus power consumption means is provided in each of the U phase and V phase, In order to consume surplus power finely, for example, it is not necessary to provide a plurality of electric heaters in increments of 100W, for example, confirmation of the wiring state of the current detection means with the power generation unit and reverse connection to an external power source (commercial system) Tidal current can be prevented with a simple and inexpensive configuration.

  In addition, by making the wiring between the U-phase and V-phase power generation units in the current detection means the same color plus and minus in each phase, and different colors for the U-phase and V-phase, Normally, such wiring has a color scheme such as red for plus and white for minus, which makes it impossible to know which line is U phase and which is V phase, but such a problem does not occur.

  Further, the power consumption variable means is composed of a semiconductor switch that changes the duty ratio and ON / OFF frequency in PWM control by a CPU provided in the control means, so that an external power source (commercial system) as described above. It is possible to consume surplus power at the last minute that does not cause a reverse power flow, and the generated power can be used effectively.

  As described above, the cogeneration apparatus according to the present invention and the wiring confirmation method of the current detection means in the cogeneration apparatus accurately confirm the wiring state of the current sensor that detects the current of the commercial system with a simple and inexpensive configuration. In addition, since surplus power can be consumed in correspondence with the amount of power, an inexpensive and efficient cogeneration device as a home cogeneration device and its current detection means A reliable wiring confirmation method can be provided.

  Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. However, as long as there is no specific description, the shape of the component described in this embodiment, its relative arrangement, and the like are not intended to limit the scope of the present invention, but are merely illustrative examples.

  FIG. 1 is a block diagram of a cogeneration apparatus that implements a wiring confirmation method for current detection means in a cogeneration apparatus according to the present invention, and FIG. 2 is a flowchart of the wiring confirmation method for current detection means according to the present invention. FIG. 2 is a schematic block diagram of a cogeneration apparatus.

  First, the outline of the cogeneration apparatus will be described with reference to FIG. In FIG. 3, reference numeral 11 denotes a gas engine that drives the generator 12. The power generated by the generator 12 is the same as the voltage and frequency of the commercial system 17 that is an external power source by the grid interconnection inverter 13. They are aligned and sent to the power usage apparatus 47 in the home through the switchboard 15 by the feeder line 49. In addition, as described above, in such a cogeneration apparatus, since the efficiency is reduced when the engine is operated at a low output, the engine is operated at a rating of, for example, 1 kW during operation, and noise is suppressed. Tuned to minimize vibration during rated operation.

  Further, a current sensor 16 is provided between the commercial system 17 and the switchboard 15, and the current of the power sent from the commercial system 17 through the switchboard 15 to the power usage device 47 is measured and provided in the inverter 13. Sent to the controller. And the control apparatus in the inverter 13 reduces the electric power which the electric power usage apparatus 47 uses, and the electric current sent to the electric power usage apparatus 47 through the switchboard 15 from the commercial system 17 becomes small, ie, the generator 12 generated electric power. When there is surplus power, the surplus power consuming heater 22 is energized to prevent reverse power flow to the commercial system 17.

  On the other hand, the engine 11 is provided with a cooling water pipe 48 for utilizing the waste heat. Further, heat is given to the cooling water in the cooling water pipe 48 also from the exhaust heat exchanger 40, and the surplus electric power is consumed. Heat is also given to the cooling water by the heater 22. The heated cooling water warms the water stored in the hot water storage tank 42 by the heat exchangers 41 and 43 or the water supplied to a heating terminal for indoor heating provided in the home (not shown). Similarly, 44 and 45 are heat exchangers for supplying hot water in the home, and 46 is an auxiliary heat source device in the case where the heat source is insufficient.

  The above is the outline of the cogeneration apparatus. Next, the present invention will be described in detail with reference to FIGS. In FIG. 1, the same components as those in FIG. 3 described above are denoted by the same reference numerals. In the figure, 11 is an engine, 12 is a generator, 13 is an AC / DC converter 18 that converts, for example, 300 V and 213 Hz alternating current generated by the generator 12 into about 300 V direct current, and commercial power that uses this direct current 300 V as an external power source. A DC / AC inverter 19 for making the AC the same voltage and frequency in the system 17 and an inverter board on which a circuit for confirming the wiring state of a current sensor 16 described later is mounted. These engine 11, generator 12, The engine unit 10 is configured by the inverter board 13 and the ECU board 14. Note that the AC / DC converter 18 and the DC / AC inverter 19 are unlikely to change in frequency and voltage in the commercial system 17 as an external power supply, whereas the power generated by the generator 12 is the usage status of the power. Because the frequency and voltage are likely to fluctuate due to this, the voltage and frequency of electricity generated by the generator 12 are provided so as to be equal to those of the commercial system 17 that is an external power source.

  14 is an ECU board that controls the engine 11 by mounting a CPU 29 that performs electronic control of a throttle, a gas electromagnetic valve, an ignition device, various sensors, and the like, and 20 is mounted on the inverter board 13 and supplies power to the ECU board 14. The control power source 21 controls the AC / DC converter 18 and the DC / AC inverter 19, and the power consumption of the surplus power consumption heater 22 provided outside the inverter board 13 is controlled by the duty (PWM) (Pulse Width Modulation) control. CPU that sends an instruction to the semiconductor switch 23 for controlling the duty ratio, 24 is an electrolytic capacitor, 25 is a rectifier that rectifies the external power supply 17, and the symbol a in FIG. A breaker that can be controlled, and a symbol 27 of 27 is attached to, for example, U In order to confirm the wiring state of the current sensor 16 (hereinafter referred to as the current sensor 16U) for detecting the phase current, a relay that turns on the U phase and the N phase, and the reference numeral c is assigned to the V phase current. This relay turns ON the V phase and the N phase in order to confirm the wiring state of the current sensor 16 to be detected (hereinafter referred to as current sensor 16V). The surplus power consumption heater 22 is also used to warm the cooling water for hot water supply with surplus power, as described with reference to FIG.

  Usually, in such a cogeneration apparatus, it is determined that the electric system can be disconnected at two places because the electric system maintenance is hindered when electricity flows through the commercial system 17 at the time of a power failure. Is one of them, and the other is a DC / AC inverter 19 serving as a gate block instead of a breaker. Reference numeral 15 is a switchboard for supplying the outputs of the commercial system 17 and the DC / AC inverter 19 to household electric power use devices, and 16 is a current sensor composed of, for example, a CT (Current Transformer). The result is sent to the CPU 29 of the inverter board 13 and is composed of a current sensor 16U for detecting a U-phase current and a current sensor 16V for detecting a V-phase current (not shown). Normally, the wiring of the current sensor 16 has a color scheme such as red for plus and white for minus. However, in this invention, it is impossible to know which line is U phase and which is V phase. The wiring from the U phase and the V phase to the CPU 29 of the inverter board 13 has the same color for plus and minus in each phase, and different colors for the U phase and the V phase, for example, the U phase is red, The phases are wired in blue, and positive and negative are judged later.

  In the cogeneration apparatus shown in FIG. 1, an engine 11 in which a throttle, a gas electromagnetic valve, an ignition device, various sensors, and the like are electronically controlled by a CPU 29 mounted on an ECU board 14 drives a generator 12. The generated alternating current of 300 V, 213 Hz, for example, is converted into a direct current of about 300 V by the AC / DC converter 18 included in the inverter board 13, and then the AC / DC inverter 19 is used to convert the AC 100 V / AC of the same frequency as the commercial system 17 as an external power source. It is converted into 200V alternating current, and is fed from the breaker a26 to the power usage device in the home via the switchboard 15.

  Current sensors 16U and 16V are provided between the commercial system 17 serving as an external power source and the switchboard 15, and the power used by the commercial system 17 is detected. Since the output of the generator 12 is constant, for example, 1 KW as described above, when the power used by the power usage apparatus in the home exceeds 1 KW, power is supplied from the commercial system 17 via the switchboard 15.

  On the other hand, if the power consumption of the power usage device in the home is less than 1 KW, the surplus electricity flows backward to the commercial system 17 as it is. In order to prevent this, the measurement result of the current sensor 16 provided between the commercial system 17 and the switchboard 15 is always sent to the control CPU 21 mounted on the inverter board 13, and this CPU 21 is sent from the sent measurement result. If a decrease in the current flowing from the commercial system 17 toward the switchboard 15 is detected, a reverse power flow may occur, and power corresponding to the surplus power is consumed to the semiconductor switch 23 that controls the power used by the surplus power consumption heater 22. The PWM control signal is sent to

  For this reason, the semiconductor switch 23 is composed of, for example, a transistor, and by inputting a PWM signal having a duty ratio that consumes power for surplus power to the base, power corresponding to surplus power is surplus power consumption heater 22 according to the transmitted signal. The reverse power flow to the commercial system 17 is prevented. Therefore, as in the conventional cogeneration apparatus as shown in Patent Document 1, surplus power consumption means (heaters) are provided in the U phase and the V phase, respectively, or the surplus power is consumed finely. It is not necessary to provide a plurality of electric heaters in steps of 100 W, and reverse power flow to the commercial system 17 can be prevented with a simple and inexpensive configuration.

  In the cogeneration apparatus configured as described above, as described above, the engine unit 10 including the engine 11, the generator 12, the inverter board 13, and the ECU board 14, and the exhaust heat exchanger 42 shown in FIG. The hot water tank shown is generally installed outside the kitchen, but the current sensor 16 that detects the current from the commercial system 17 is installed at the switchboard 15 in the home. To the inverter board 13 of the cogeneration device installed outside the cooking area.

  And this wiring becomes three lines corresponding to the U-phase, N-phase, and V-phase three wires, but this wiring is wrong, and there is no surplus power. May occur. In order to detect this, in the present invention, an electrolytic capacitor 24, a rectifier 25, a relay b 27, and a relay c 28 are provided in the inverter board 13 in parallel with the surplus power consumption heater 22. Hereinafter, the wiring confirmation method of the current sensor 16 of the present invention using these will be described with reference to the flowchart of FIG. Note that the wiring confirmation of the current sensor 16 is performed only once when the cogeneration apparatus is installed.

  When the process starts in step S20 in FIG. 2, the frequency n (Hz) for turning on / off the surplus power consumption heater 22 by the semiconductor switch 23 is set to 1 (Hz), which is smaller than the frequency of the commercial system 17, for example. The The frequency n (Hz) for turning on / off the surplus power consumption heater 22 is as described above, for example, for the toilet seat of a toilet that is PWM controlled using an inverter, for example, operating and stopping the compressor of a refrigerator. The frequency at which the surplus power consumption heater 22 is turned ON / OFF when the ON / OFF timing of the power use device such as the heater or the air conditioner coincides with the timing of checking the wiring state of the current sensor 16 and the correct determination cannot be made. In order to cope with this by changing n (Hz), for example, other frequencies such as 3 (Hz) and 10 (Hz) that are not easily influenced by the ON / OFF timing of the power usage apparatus are used. However, the frequency described here is merely an example, and the frequency is not limited to the above-described frequency as long as it is lower than the frequency of the commercial system 17.

  In the next step S22, the frequency n (Hz) for turning on / off the surplus power consumption heater 22 is set to 1 (Hz), and in the next step S23, the breaker a26 in FIG. 1 is turned on. The breaker a26 is preferably constituted by a relay and is controlled by the CPU 21 of the inverter board 13 together with the relay b27 and the relay c28.

  Then, 200 V between the U phase and the V phase flows from the commercial system 17 via the switchboard 15 and the breaker a26, and the current rectified by the rectifier 25 charges the electrolytic capacitor 24, for example. Therefore, the CPU 21 turns ON / OFF at the frequency of 1 Hz that sets the surplus power consumption heater 22 in the next step S24. Then, each time, a large current flows or stops in the surplus power consumption heater 22, and if the U phase and the V phase are correctly connected, the surplus power consumption heater 22 measures the current measured by the current sensor 16 accordingly. It increases when turned on and decreases when turned off. When the U phase and V phase are reversely connected, the current flowing through the current sensor 16 decreases when the surplus power consumption heater 22 is turned on, and increases when the surplus power consumption heater 22 is turned off thereafter. If no change occurs, there is a possibility that the disconnection or wiring connection is not performed properly.

  In the next step S25, the CPU 29 determines whether or not the U phase and the V phase are correctly connected from the value of the current flowing through the current sensor 16, stores the result, and decreases and increases the current during, for example, 1 Hz. If both of the above occur and the accuracy of the determination is doubtful, it is stored that the determination is impossible.

  In the next step S26, the CPU 29 disconnects the breaker a26 and turns on the relay b27 for connecting the U phase and the N phase. Then, similarly to the above, 100 V between the U phase and the N phase flows from the commercial system 17 via the switchboard 15 and the breaker b27, and the current rectified by the rectifier 25 charges the electrolytic capacitor 24, for example. Therefore, the CPU 21 turns ON / OFF at the frequency of 1 Hz that sets the surplus power consumption heater 22 in the next step S27.

  Then, each time a large current flows or stops in the surplus power consumption heater 22, and if the U phase and the N phase are correctly connected, the surplus power consumption heater 22 measures the current measured by the current sensor 16U accordingly. It increases when turned ON, and the current of the current sensor 16V connected to the V phase does not change. When the U phase and the V phase are reversely connected, the current flowing through the current sensor 16U does not change when the surplus power consumption heater 22 is turned on, and the current of the current sensor 16V increases. If the values of both the current sensor 16U and the current sensor 16V do not change, there is a possibility that disconnection or wiring connection has not been performed well.

  Therefore, in the next step S28, the CPU 29 determines which current sensor 16U and current sensor 16V the current sensor 16 currently connected to the U-phase and V-phase is based on the current value flowing through the current sensors 16U and V, respectively. For example, if both the current decrease and the increase occur during 1 Hz and the accuracy of the determination is doubtful, it is stored that the determination is impossible as described above.

  In the next step S29, the CPU 29 disconnects the breaker b27 and turns on the relay c28 for connecting the V phase and the N phase. Then, similarly to the above, 100 V between the V phase and the N phase flows from the commercial system 17 through the switchboard 15 and the breaker c28, and the current rectified by the rectifier 25 charges the electrolytic capacitor 24, for example. Therefore, the CPU 21 turns on / off at the frequency of 1 Hz that sets the surplus power consumption heater 22 in the next step S30.

  Then, each time it is turned ON / OFF, a large current flows or stops in the surplus power consumption heater 22, and if the V phase and the N phase are correctly connected, the current measured by the current sensor 16V is the surplus power. It increases when the consumption heater 22 is turned on, and the current of the current sensor 16U connected to the U phase does not change. When the U phase and the V phase are reversely connected, the current flowing through the current sensor 16V does not change when the surplus power consumption heater 22 is turned on, and the current of the current sensor 16U increases. If the values of both the current sensor 16U and the current sensor 16V do not change, there is a possibility that disconnection or wiring connection has not been performed well.

  Therefore, in the next step S31, the CPU 29 determines which current sensor 16V and current sensor 16U the current sensor 16 currently connected to the V-phase and U-phase is based on the current value flowing through the current sensors 16V and U, respectively. For example, if both the current decrease and the increase occur during 1 Hz and the accuracy of the determination is doubtful, it is stored that the determination is impossible as described above.

  When the process is performed in this way, the CPU 29 determines whether or not the state of each wiring has been confirmed in the next step S33, and if so, the process proceeds to step S39 to end the process, and it is stored that the determination is impossible. If there is an item, the process proceeds to step S34 to determine whether or not the current frequency n is 1. Since n = 1 as described above, the process proceeds to step S35, and the frequency n (Hz) for turning on / off the surplus power consumption heater 22 by the semiconductor switch 23 is set to 3 (for example, smaller than the frequency of the commercial system 17). Hz).

  That is, as described above, when the ON / OFF timing of the power usage device and the ON / OFF timing of the surplus power consumption heater 22 for checking the wiring state are synchronized, the current that should increase should decrease or decrease. In this case, the frequency n (Hz) at which the surplus power consumption heater 22 is turned on / off is changed in step S35. The frequency is set to 3 (Hz), which is smaller than the frequency. Thereafter, the processing returns to step S22, and the processing described above is repeated.

  If the state of each wiring cannot be confirmed even in the process of setting this frequency to 3 (Hz), the process proceeds to step S36 to determine whether or not the current frequency n is 3, and the current n = 3. Therefore, the process proceeds to step S37, and the frequency n (Hz) for turning on / off the surplus power consumption heater 22 by the semiconductor switch 23 is set to, for example, 10 (Hz) smaller than the frequency of the commercial system 17. And a process returns to step S22 and the process demonstrated above is repeated.

  Further, if the state of each wiring cannot be confirmed even in the process in which this frequency is set to 10 (Hz), the process proceeds from step S36 to step S38 until the frequency n is returned to 1 and the state of each wiring can be confirmed. to continue. However, since it is difficult to keep the processing looping forever, it is preferable to measure the number of loops and forcibly stop the processing after a predetermined number of loops.

  In this way, the wiring state between the current sensor 16 and the inverter board 13 is confirmed. As a result, for example, the current sensor 16U is actually connected to the V phase, and the current sensor 16V is actually connected to the U phase. If the U-phase and V-phase are wired in reverse, the CPU 29 stores the respective states in the storage device, and the stored phase order is determined for the subsequent measurement results from the current sensor 16. The surplus power consumption by the surplus power consumption heater 22 is determined and a control signal is sent to the semiconductor switch 23. Therefore, the surplus power consuming heater 22 is supplied with power substantially equal to the surplus power, and the power generated by the generator 12 is effectively used.

  The result of checking the wiring state between the current sensor 16 and the inverter board 13 is not only stored and processed on the CPU 29 side, but also displayed on the outside and manually changed. Of course, it is also good.

  In the above description, the frequency n (Hz) for turning on / off the surplus power consumption heater 22 by the semiconductor switch 23 is set to three types of 1 (Hz), 3 (Hz), and 10 (Hz). Of course, the frequency may be reduced, and the order in which the frequency is changed may be changed from the larger to the smaller one instead of from the smaller to the larger one. In this method, the increase / decrease in the current of the surplus power consuming heater is measured and determined. However, the present invention can be similarly realized by determining the power instead of the current.

  In this way, by checking the wiring state of the current sensor 16 with the inverter board 13, the ON / OFF cycle of the surplus power consumption heater 22 can be changed even when the household power usage device is turned ON / OFF. It is possible to check whether the power usage device is ON / OFF or the surplus power consumption heater 22 is ON / OFF, and it is possible to check the wiring status of the current sensor 16 with the inverter board 13 with a simple and low-cost configuration. It can be done accurately without waking up. Further, the power consumption of the surplus power consumption heater 22 is changed by PWM, so that surplus power can be consumed at the last minute without causing a reverse power flow to the commercial system 17, and the generated power can be effectively used. Available.

  Further, since the surplus power consumption heater 22 is installed in the direct current portion between the AC / DC converter 18 and the DC / AC inverter 19 constituting the engine unit 10, the commercial system 17 is rectified and connected to the surplus power consumption heater 22. However, as in the conventional cogeneration apparatus described above, the surplus power consumption heater 57 (FIG. 4) is provided in each of the U phase and V phase, and the surplus power is finely consumed. It is not necessary to provide a plurality of electric heaters 57 step by step, and it is possible to check the wiring state of the current sensor 16 with the inverter board 13 and to prevent reverse power flow to the commercial system 17 with a simple and inexpensive configuration.

  In addition, since the wiring between the U-phase and V-phase inverter boards 13 in the current sensor 16 has the same color for plus and minus in each phase, and different colors for the U-phase and V-phase, Is not U-phase and it is not possible to know which line is V-phase.

  According to the present invention, it is possible to accurately check the wiring of the current sensor 16 at the time of installing the cogeneration apparatus with a simple and inexpensive configuration, and it is possible to consume surplus power corresponding to the amount of power. Therefore, it is possible to provide an inexpensive and efficient cogeneration apparatus as a household cogeneration apparatus and a wiring confirmation method for the current sensor 16.

It is a block diagram of the cogeneration apparatus which implements the wiring confirmation method of the current detection means in the cogeneration apparatus according to the present invention. It is a flowchart of the wiring confirmation method of the electric current detection means of this invention. It is a schematic block diagram of a cogeneration apparatus. It is a block diagram of the conventional cogeneration apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Engine unit 11 Engine 12 Generator 13 Inverter board 14 ECU board 15 Distribution board 16 Current sensor 17 Commercial system 18 AC / DC converter 19 DC / AC inverter 20 Control power supply 21 CPU
22 Excessive power consumption heater 23 Semiconductor switch 24 Electrolytic capacitor 25 Rectifier 26 Breaker 27 Relay 28 Relay 29 CPU

Claims (7)

A power generation unit connected to an external power source composed of a U phase, an N phase, and a V phase and a power usage device, the power generation unit, a power generation unit, a surplus power consumption unit that consumes surplus power of the power generation unit, And a control means for controlling the power generation means and the surplus power consumption means. The external power source is provided with a current detection means for measuring the currents in the U phase and the V phase . In the cogeneration apparatus that controls the surplus power consumption means to consume the surplus power generated by the power generation means based on the output,
The power generation unit includes power consumption variable means for changing a duty ratio by PWM (Pulse Width Modulation) control of the power consumption of the surplus power consumption means, and the control means supplies the power consumption variable means to an external power frequency. In addition, the surplus power consuming means is turned on / off at a small frequency, and the ON / OFF frequency of the surplus power consuming means is set according to the wiring state confirmation status of the current detecting means provided in the U phase and V phase of the external power source. Configured to change,
Further, the control means includes a current amount in each of the current detection means that changes with ON / OFF of the surplus power consumption means when the surplus power consumption means and the U phase and N phase of the external power source are connected. And, when the surplus power consumption means and the V phase and N phase of the external power source are connected, the U from the amount of current in each of the current detection means that changes with ON / OFF of the surplus power consumption means A cogeneration apparatus having a function of confirming a wiring state between the current detection means provided in the phase and the V phase and the power generation unit.   The power generation unit includes AC / DC conversion means for converting the output of the power generation means to DC, and DC / AC conversion means for converting the AC / DC conversion means output to AC, and the surplus power consuming means is the AC / DC conversion means. The cogeneration apparatus according to claim 1, wherein the cogeneration apparatus is provided between the conversion unit and the DC / AC conversion unit.   The power generation unit includes first switch means for simultaneously linking U-phase, N-phase, and V-phase outputs of the DC-AC conversion means output with an external power source, and a second switch for linking the U phase with the external power source. Switch means and third switch means for interconnecting the V phase with the external power source, and the control means is configured to switch the U-phase and V-phase wirings in reverse by turning on the first switch means. 3. The cogeneration apparatus according to claim 1, wherein the confirmation is performed by confirming the wiring state of the U phase and the V phase by turning on the second and third switch means.   The wiring between the U-phase and V-phase power generation units in the current detection means has the same color for plus and minus in each phase, and different colors for the U-phase and V-phase. The cogeneration apparatus according to any one of claims 1 to 3.   5. The power consumption variable means is constituted by a semiconductor switch that changes a duty ratio and ON / OFF frequency in PWM control by a CPU provided in the control means. Cogeneration device described in 1. Power usage device and the U-phase, N phase, comprising a power generating unit connected to an external power source consisting of V phase, prior to said power generation unit of each provided current sensing means and the U-phase and V-phase in Kigaibu power A wiring confirmation method for current detection means in a cogeneration device, wherein the wiring state is confirmed by energizing surplus power consumption means that consumes surplus power of the power generation means constituting the power generation unit,
The surplus power consumption means is turned on / off at a frequency smaller than the external power supply frequency in a state where the U-phase, N-phase, and V-phase in the power generation unit and the external power supply are linked, and the current detected by the current detection means A first step of determining the U-phase and V-phase wiring directions by increase / decrease, and the surplus power consuming means in a state where the surplus power consuming means and the U phase and N phase of the external power supply are connected to each other. Increase / decrease in current detected by each of the current detection means when ON / OFF at a smaller frequency, and the surplus power in a state where the surplus power consumption means and the V phase and N phase of the external power source are connected a second step of determining the correctness of the wiring phase order by increasing or decreasing the current detected by each of said current detecting means when the consumer means and ON / OFF at a smaller frequency than the external power source frequency The first step and one of the wiring direction and phase sequence errata in the second step, or if both of the confirmation could not, the ON / OFF frequency of the previous SL excess over - power means from said external power source frequency And the third step of performing the first and second steps, and
A wiring confirmation method for a current detection means in a cogeneration apparatus, wherein the state of wiring of the current detection means with the power generation unit is confirmed by changing a frequency for turning on / off the surplus power consumption means.   The wiring check method of the current detection means in the cogeneration apparatus according to claim 6, wherein the surplus power consumption means is connected to a direct current portion in the power generation unit to check the wiring state of the current detection means.

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