JP2000059992A - Power-supply feeding apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the feedings of improper power supplies to electric loads, by inhibiting the operation of an internal combustion engine corresponding to deteriorative AC/DC converting means when judging the deteriorations of at least one of them based on their DC voltages. SOLUTION: Such data signals as the rotational speed of an internal combustion engine 10 and the temperature of its refrigerant medium are fed from an engine control unit (ECU) 32 to a system control unit(SCU) 40. Also, a sensor group 91 comprising the sensors provided in the respective AC/DC converting means of converters (CONV) 76-79 senses the voltage values of the respective DC voltages smoothed by smoothing capacitors to feed the sensed values to the judgement means of the SCU 40. Then, the SCU 40 inhibits for the ECU 32 to operate the internal combustion engine 10 corresponding to the voltage smoothing capacitors judged as deteriorative ones. Thereby, the feedings of the powers of improper power supplies to electric loads can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply having an AC / DC converter for converting an AC voltage generated by a plurality of generators driven by a plurality of internal combustion engines into a DC voltage.

[0002]

2. Description of the Related Art An alternator driven by an internal combustion engine is well known. A power supply that supplies power to a load is conceivable. In such a power supply device, the AC output of each generator is exchanged in consideration of variation in the output of each AC generator.
The DC voltage obtained by once converting to DC by the direct converter is individually adjusted, and then a common AC voltage is obtained by the common DC converter.

[0003]

In the AC-DC converter as described above, a capacitor is used as a smoothing means in order to suppress a ripple component of a rectified voltage.
This capacitor generally has a short life, and deterioration of the capacitor may cause a large ripple to be mixed into the DC output voltage.

[0004] The present invention has been made in view of the above points, and an object of the present invention is to provide a power supply device capable of preventing improper supply of power to an electric load. Is to do.

[0005]

A power supply apparatus according to the present invention comprises a plurality of AC / DC converters for converting an AC voltage generated from a plurality of generators each driven by a plurality of internal combustion engines into a DC voltage. Means for converting the DC voltage to an AC voltage and supplying the AC voltage to an electric load, and a control means for controlling the internal combustion engine based on the magnitude of the electric load. A power supply device comprising: a controller configured to determine at least one deterioration of the AC / DC converter based on the DC voltage; and Prohibition means for prohibiting operation of the internal combustion engine corresponding to the AC / DC conversion means.

That is, according to the feature of the present invention, when the determination means determines the deterioration, the operation of the internal combustion engine corresponding to the AC / DC conversion means is prohibited, so that the improper power supply power to the electrical load can be reduced. Supply can be prevented. According to another feature of the present invention, an internal combustion engine other than the internal combustion engine whose operation is prohibited is selectively operated according to the magnitude of the electric load, so that a preferable power supply voltage is supplied to the electric load. can do.

According to another feature of the present invention, there is further provided a circulation passage for circulating a fluid absorbing heat generated from the internal combustion engine, and a heat exchanger provided in the circulation passage.
Since the control means controls the internal combustion engine also according to the temperature of the fluid, it is possible to supply preferable heat to a thermal load. Still further, according to another feature of the present invention, the deterioration of the AC / DC converter is determined by knowing the decrease in the capacitance of the voltage smoothing capacitor, so that the deterioration can be accurately determined.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an outline of a power supply device according to the present invention. A combustible gas, for example, natural gas, drawn from a gas supply source 11 and air drawn from an air inlet 12 are mixed in a mixer 13, and the mixed gas is mixed in a combustion chamber of a cylinder 14 of an internal combustion engine 10. (Not shown), the fuel is burned, and then exhausted from the exhaust port 16 through the heat exchange unit 15 as exhaust gas. The combustion of the air-fuel mixture sucked into the combustion chamber of the cylinder 14 drives the rotation of a crankshaft (not shown) of the internal combustion engine 10, and the rotation of the crankshaft is controlled by the rotor of the generator 70 connected to the crankshaft. (Not shown), the generator 70 generates electric power by this rotation operation, and the generator 70 outputs a generated voltage.

The cooling medium (coolant) sealed in the circulation channel 25 is pumped up by the pump 24 and circulated in the circulation channel 25 via the heat exchangers 21 and 22 and the heat exchanger 23. I do. The cooling medium described above absorbs the heat generated by the combustion of the air-fuel mixture in the heat exchange section 21 and absorbs the heat generated from the exhaust gas in the heat exchange section 22 to cool the internal combustion engine 10.

Further, a heat absorbing medium, for example, water previously stored in a hot water supply tank 27 is pumped up by a pump 26 and circulated through a pipe 28 via a heat exchanger 23. This heat absorbing medium absorbs heat from the cooling medium sealed in the circulation channel 25 in the heat exchanger 23. The above-described device generates electric power by operating the internal combustion engine 10, and
By absorbing the heat generated from the internal combustion engine 10, the heat absorbing medium stored in the hot water supply tank 27 can be heated.

A group of sensors 31 provided in the internal combustion engine 10, for example, a crankshaft reference position sensor and a coolant temperature sensor, are connected to an engine control unit (hereinafter referred to as an ECU) 32. The ECU 32 takes in the value of the output signal from the sensor group 31 as an engine parameter, calculates a control value required for controlling the internal combustion engine 10, for example, an ignition timing and a gas supply amount, and based on the control value, calculates the internal combustion engine 10 Is controlled. Also, ECU
Reference numeral 32 is connected to a system control unit (SCU) 40 via a communication interface as described later. By this communication means, the internal combustion engine 10
Data signals such as the rotation speed of the motor and the temperature of the cooling medium
The SCU 40 supplies the ECU 32 with command signals for setting the engine speed and for starting, stopping, and decelerating the internal combustion engine 10. SCU4
0, an operation panel 50 described later is connected, and a signal corresponding to an input operation by an operator of the operation panel is transmitted to the SCU 40.
While the internal combustion engine 1 in the SCU 40
A signal corresponding to the determination result of the operation state of 0 or the operation state of the inverter controller 90 is supplied from the SCU 40 to the operation panel 50.

The SCU 40 is connected to an inverter control unit (hereinafter, referred to as ICU) 92 of an inverter controller 90, and controls the ON / OFF operation of contactor switches (hereinafter, referred to as CS) 71 to 75 described later. A signal for controlling the inverter controller 90 is supplied from the SCU 40 to the ICU 92. On the other hand, a converter (hereinafter referred to as CONV) 7 described later
6 to 80, a sensor group 91 is provided,
The sensor group 91 detects a voltage and a current generated from each of the CONVs 76 to 80, and detects an A / D of the SCU 40 described later.
The detection signal is supplied to the converter 44. The sensor group 9 is located near the output terminal (not shown) of the inverter 81.
3 are provided, and the sensor group 93 includes an inverter 81
ICU 9 detects load voltage and load current generated from
2 to supply a detection signal to an A / D converter (not shown).
The ICU 92 supplies the detected load voltage and load current values as data signals to the SCU 40 at predetermined timings, for example, every 200 milliseconds.

The above-described generator 70 is connected to CS71 of the inverter controller 90.
The CS 71 performs an on / off operation in accordance with a control signal issued from the SCU 40, and controls power supply from the generator 70. When a plurality of, for example, four internal combustion engines are mounted, the generators of the internal combustion engines are connected to CS71 to CS74, respectively. Further, the commercial power supply 60 is connected to the CS 75, and the CSs 71 to 75 are selectively connected according to the power required to drive a load (not shown) connected to the inverter controller 90. Thus, the generator and the commercial power supply are selectively connected to the load.

CS71-CS75 are CONV76-
And CONVs 76 to 79 convert an AC voltage, for example, three-phase 300 volts, generated from the generator into a DC voltage, for example, 180 volts.
0 converts an AC voltage supplied from the commercial power supply 60, for example, 200 volts for three phases into a DC voltage, for example, 180 volts. The CONVs 76 to 80 are connected to an inverter 81. The inverter 81 converts a plurality of supplied DC voltages into a common AC voltage, for example, 100 volts, and converts the AC voltage into a load ( (Not shown).

FIG. 2 shows a system control unit of the power supply device shown in FIG. The operation panel 50 described above
It is connected to an input / output bus 42 via an interface circuit 41. The input / output bus 42 inputs and outputs a data signal or an address signal to / from the CPU 45. The sensor group 91 provided in the CONVs 76 to 80 is a multiplexer (hereinafter referred to as MPX) in the SCU 40.
43). The MPX 43 outputs one of the output signals output from the sensor group 91 in response to a command output from the CPU 45 at a predetermined timing.
Switches for selectively supplying one to the A / D converter 44. The A / D converter 44 converts the supplied signal into a digital signal and supplies the digital signal to the input / output bus 42. A communication interface circuit 49 is connected to the input / output bus 42. This communication interface circuit 49
Is provided with a port (not shown) for serial communication in accordance with a predetermined communication standard, for example, the RS-232C standard.
Receiving data signals supplied from the ECU 32 and the ICU 92, and from the CPU 45 to the ECU 32 and the ICU
A command signal issued to the CPU 92 is transmitted.

The input / output bus 42 includes a ROM 4
6, a RAM 47 and a non-volatile memory 48 are connected. The ROM 46 stores a program for determining the value of the capacitance of the voltage smoothing capacitor according to the flowchart described in FIG. FIG. 3 shows an inverter control unit of the power supply device. As described above, the AC voltage generated by the generator 70 driven by the internal combustion engine 10, for example, three-phase 300 volts,
1 to the rectifier circuit element 95 of the CONV 76. The rectifier circuit element 95 is formed of, for example, a bridge circuit composed of a diode, and converts the supplied AC voltage to a DC voltage, for example, 180 volts. The converted DC voltage is converted to a smoothed DC voltage by a voltage smoothing capacitor 101, and then supplied to an inverter 81 via a discharging resistor 102 connected in parallel with the voltage smoothing capacitor 101 to be shared. , For example, 100 volts. Thereafter, the converted AC voltage is supplied to the electric load 100.

In the vicinity of both ends of the above-described discharge resistor 102, a voltage detector for detecting a voltage between both ends of the discharge resistor 102 is provided. The above-described sensor group 91 is constituted by the voltage detector and a current detector (not shown). The discharge resistor 102 detected by the voltage detection unit
Is supplied to the A / D converter 44 of the SCU 40. In addition, a voltage detection unit that detects the output voltage of the INV 81 is provided near the output terminal (not shown) of the INV 81. The voltage sensor and the current detector (not shown) constitute the sensor group 93 described above.

In the above description of FIG. 3, only the AC voltage supplied from the generator 70 has been described. However, as shown in FIG. 1, when a plurality of, for example, four generators are mounted, Each generator is C
Each of the AC voltages generated by the respective generators is connected to each of the CONVs 76 to 79 via S71 to 74, and the AC voltage generated by each of the generators is smoothed by the rectifier circuit element and the smoothing capacitor provided in each of the CONVs 76 to 79. After being converted into a voltage, IN is connected via a discharge resistor and a sensor group 91 provided in each of the CONVs 76 to 79.
It is supplied to V81. The sensor group 91 detects each voltage value of the smoothed DC voltage smoothed by the smoothing capacitor, and detects each detected signal as an SCU40.
Is supplied to the A / D converter. Also, CONV
Each of 76 to 79 is provided with a constant voltage circuit 96. The constant voltage circuit 96 adjusts the value of the smoothed DC voltage output from the CONVs 76 to 79 to a predetermined voltage.

The above-described ECU 32, SCU 40 and IC
The control means and the inhibition means are constituted by U92, the generator is constituted by the generator 70, the AC-DC converter is constituted by the CONVs 76 to 80, and the DC-DC converter is constituted by the INV81. FIG. 4 shows an operation panel of the engine control system. The display panel 51 displays a determination result of determining the operation state of the inverter controller and contents stored in the nonvolatile memory 48. The emergency stop switch 52 is a switch used when the operator wants to stop the operation of the power supply device urgently. The reset switch 53 is a switch used when restarting the power supply device. Display L during system startup
The ED 54 is a light emitting diode that indicates that the power supply device is activated, and a system emergency stop display LED 55
Is a light emitting diode that lights up when the power supply device stops in an emergency. Further, the display ON switch 56 is a switch for displaying the display content on the display panel 51, and the display OFF switch 57 is a switch for deleting the display on the display panel 51.

In the following, the power supply device shown in FIG. 1 is activated, and the ECU 32, the SCU 40 and the IC
It is assumed that all initialization processes such as initialization of variables used in U92 and activation of a timer described later have been completed. Also, it is assumed that a predetermined number of internal combustion engines, for example, four are installed. FIG. 5 shows a subroutine for determining the capacity of the voltage smoothing capacitor. This subroutine is executed at a predetermined timing, for example, when the internal combustion engine stops.

First, it is determined whether or not the internal combustion engine is operating (step S11). When it is determined that the internal combustion engine is operating, this subroutine is immediately terminated. When it is determined that the internal combustion engine is not operating, that is, the internal combustion engine is stopped, it is determined whether or not the time from when the internal combustion engine was stopped is t _{0 based} on the value of the timer that has been started in advance ( Step S1
2). If it is determined that the time is not t ₀ , the present subroutine ends. If it is determined that the time is t ₀ , a voltage V ₀ # across the discharge resistor is detected (step S13). The # of the voltage V ₀ # between both ends indicates the number of the internal combustion engine, and when four internal combustion engines are mounted, # is 1 to 4, and # indicates the V ₀ #. The voltage across the discharge resistor corresponding to the internal combustion engine of the number. Next, it is determined whether or not the time from when the internal combustion engine is stopped is t ₁ (step S1).
14). Time when not determined t _1, this subroutine ends. Time when it is determined that the t ₁ detects the voltage V ₁ # across the discharge resistor (step S15). Next, the capacitance C of the voltage smoothing capacitor
#, For example,

[0022]

(Equation 1)

Calculated based on the equation (step S
16) It is determined whether the calculated capacity C # is larger than a predetermined capacity C _LIFE (step S17). Where R #
Is the resistance value of the discharge resistor. When it is determined that the capacity C # is equal to or _larger than the predetermined capacity _CLIFE , the present subroutine ends. When it is determined that the capacity C # is smaller than the predetermined capacity _CLIFE , a display indicating that deterioration has occurred in the voltage smoothing capacitor corresponding to the internal combustion engine of the number indicated by # is displayed on the display panel 51 (step). S18).
For example, when it is determined that the value of the capacitance C2 is smaller than C _{LIFE, a} display such as "ERR2 CONDENSER" is displayed, and the display panel 51 indicates that the voltage smoothing capacitor corresponding to the second internal combustion engine has deteriorated. It is displayed. After the display on the display panel 51, the present subroutine ends.

Thereafter, when the SCU 40 issues a command to start the internal combustion engine to the ECU 32, SCU
The CU 40 does not issue a start command to prohibit start of the internal combustion engine corresponding to the voltage smoothing capacitor determined to be deteriorated. Further, when there is an internal combustion engine that can be started other than the internal combustion engine whose starting is prohibited, the internal combustion engine that can be started as a substitute for the internal combustion engine whose starting is prohibited is selectively started according to the magnitude of the electric load. It is good. Further, the temperature of the cooling medium is detected by a temperature sensor (not shown) provided in the circulation path 25 of the cooling medium, and the alternative internal combustion engine is started according to the magnitude of the thermal load. As shown in FIG. 1, when heating a heat absorbing medium, for example, water stored in a hot water supply tank by using heat generated from an internal combustion engine, heating can be performed without reducing the amount of heat applied to the heat absorbing medium. You can.

FIG. 6 shows that when the internal combustion engine is stopped,
5 shows a voltage across the discharge resistor that changes with time. Until the internal combustion engine stops, the value of the voltage across the discharge resistor is a constant value, for example, 180 VDC. At the same time when the internal combustion engine is stopped, the electric charge stored in the voltage smoothing capacitor is discharged by the discharging resistor, and the value of the voltage between both ends attenuates exponentially, for example. The voltage between both ends at t ₀ in this decay process is represented by V ₀ #, t
Assuming that the voltage between both ends in ₁ is V ₁ #, the voltages V ₀ # and V ₁ # between both ends are detected in steps S13 and S15 of the flowchart shown in FIG. 5 described above.

In the embodiment described above, the expression (1)
, The capacity C # of the voltage smoothing capacitor is calculated on the basis of

[0027]

(Equation 2)

By calculating a time constant T # of a circuit including a smoothing capacitor and a discharging resistor as shown in FIG.
Obviously, the deterioration of the voltage smoothing capacitor may be determined. Where # is, as described above,
It shows the number of the internal combustion engine. Further, in the above-described embodiment, when the internal combustion engine is stopped, the deterioration of the smoothing capacitor is determined from the value of the capacitance of the voltage smoothing capacitor or the value of the time constant of the circuit including the voltage smoothing capacitor and the discharging resistor. As a result, during the operation of the internal combustion engine, the value of the smoothed DC voltage is sampled from the A / D converter 44 of the SCU 40 and taken in, and the waveform of the smoothed DC voltage is analyzed, for example, the ripple component is extracted to determine the magnitude of the ripple. Obviously, a configuration for determining the deterioration of the smoothing capacitor may be adopted.

In this specification, the term "internal combustion engine" refers to an internal combustion engine including a hybrid engine and the like.

[0030]

As described above, according to the power supply device of the present invention, when the determination means determines the deterioration, the operation of the internal combustion engine corresponding to the AC / DC conversion means is prohibited, so that the electric load is reduced. Can be prevented from being inappropriately supplied to the power supply. According to another feature of the present invention, an internal combustion engine other than the internal combustion engine whose operation is prohibited is selectively operated according to the magnitude of the electric load, so that a preferable power supply voltage is supplied to the electric load. can do.

According to another feature of the present invention, there is further provided a circulation passage for circulating a fluid for absorbing heat generated from the internal combustion engine, and a heat exchanger provided in the circulation passage.
Since the control means controls the internal combustion engine also according to the temperature of the fluid, it is possible to supply preferable heat to a thermal load. Still further, according to another feature of the present invention, the deterioration of the AC / DC converter is determined by knowing the decrease in the capacitance of the voltage smoothing capacitor, so that the deterioration can be accurately determined.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an outline of a power supply device according to the present invention.

FIG. 2 is a block diagram showing a system control unit of the power supply device shown in FIG.

FIG. 3 is a circuit diagram showing an inverter control unit of the power supply device shown in FIG.

FIG. 4 is a front view showing an operation panel of the power supply device shown in FIG. 1;

FIG. 5 is a flowchart showing a subroutine for determining the capacity of a voltage smoothing capacitor.

FIG. 6 is a graph showing a voltage between both ends of a discharge resistor that changes with time when an internal combustion engine is stopped.

[Explanation of symbols]

Reference Signs List 10 internal combustion engine 25 circulation passage 23 heat exchanger 32 engine control unit (control means, prohibition means) 40 system control unit (control means, prohibition means, determination means) 92 inverter control unit (control means) 70 generator (generator) 76, 77, 78, 79 Converter (AC-DC converter) 81 Inverter (DC-DC converter)

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H02M 7/06 H02M 7/06 H5H590 H02P 9/04 H02P 9/04 J (72) Inventor: Tsutomu Wakitani Saitama 1-4-1, Chuo, Wako, F-term F-term in Honda R & D Co., Ltd. (Reference) 2G036 AA04 AA24 BA37 BB02 CA06 3G093 AA16 AB00 DA05 DA13 DB00 DB23 EC01 FA11 FB05 5G053 AA08 BA04 CA01 DA01 EA01 EB01 5G065 BA00 DA01 DA06 FA00 HA04 KA02 KA05 LA01 LA07 MA01 MA02 NA01 5H006 AA04 CA07 CB00 CC04 DA04 DB01 DB07 DC05 FA04 GA04 5H590 AA15 AA22 BB15 CA07 CA21 CA28 CD01 CD03 EA14 EB02 EB12 FA05 FB01 GA02 HA02 HA18 HA27 HB00 JA02 KK04 KK

Claims (4)

[Claims] 1. A plurality of AC-DC converters for converting an AC voltage generated by a plurality of generators each driven by each of a plurality of internal combustion engines into a DC voltage, and converting the DC voltage into an AC voltage. A power supply device comprising: a single cross-conversion converter for supplying the electric load to an electric load; and control means for controlling the internal combustion engine based on the magnitude of the electric load. Means for determining at least one deterioration of the AC / DC conversion means based on the DC voltage; and operation of the internal combustion engine corresponding to the AC / DC conversion means when the determination means determines deterioration. And a prohibition unit for prohibiting the power supply. 2. The power supply device according to claim 1, wherein the control means selectively operates an internal combustion engine other than the internal combustion engine whose operation is prohibited, according to the magnitude of the electric load. 3. A circulation path for circulating a fluid that absorbs heat generated from the internal combustion engine, and a heat exchanger provided in the circulation path, wherein the control unit also controls a temperature of the fluid. 3. The power supply according to claim 2, wherein the internal combustion engine is controlled accordingly. 4. Each of the AC / DC converting means includes a voltage smoothing capacitor, and the determining means includes a capacity calculating means for calculating the capacity of each of the voltage smoothing capacitors based on the DC voltage. 2. The power supply device according to claim 1, wherein when it is detected that the capacity is smaller than a predetermined value, it is determined that the AC / DC converter has deteriorated.