JPH10117428A - Cooling device for power converter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To supply onboard power without causing blackouts, when the cooling fan of a power converting element gets out of order by stopping a shaft-driven power generator by setting the operable time of a power converter to an inverse-time characteristic by using the temperature of the power-converting element. SOLUTION: When a forced cooling fan 33 stops, a wind speed sensor 34 detects that the fan 33 has stopped or that the air quantity from the fan 33 has been disturbed. The temperature detected by means of a temperature- detecting element 36 is converted into a voltage by means of a temperature- voltage converting circuit 37, and the output voltage of the circuit 37 is inputted to a temperature function circuit 38. Since the circuit 38 has an inverse-time characteristic, preset to a time shorter than the operable time allowable by the temperature of the element 30 by the inputted voltage and detect the temperature of the element 30, the element 30 not only works as a fixed-time timer, but also as a timer having the inverse-time characteristic which varies depending upon the degree of temperature rise. Therefore, the element 30 can be protected until a shaft generator is stopped, and power supply switching can be performed smoothly.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a main shaft drive generator for a marine vessel, and more particularly to a cooling device for a power converter for converting power by a converter and an inverter.

[0002]

2. Description of the Related Art A main shaft drive generator (hereinafter abbreviated as a shaft generator) in which a generator is connected to a main engine or a main shaft system to supply electric power at a lower price than the main engine for the purpose of fuel saving and labor saving of a ship.
Is used.

[0003] A general shaft power generator will be described with reference to the configuration diagram of FIG. In the figure, 1 is a shaft generator, 2 is a converter, 3 is an inverter, 4 is a synchronous phase adjuster, 5 is a main engine, 6 is a propeller, 7 is a load, 8 is a circuit breaker, 9 is a bus, and 10 is an output frequency. A command setter, 11 is an output frequency detector, 12 is a frequency controller, 13 is a current limiter that limits a current command value by a deviation between the output frequency command and the output frequency detection value, 14 is a current detector, and 15 is a current command value. Inverter 3 and converter 2 so that the current detection value matches
, 16 is a phase controller for the converter 2, 17 is a phase controller for the inverter 3, 18 is a voltage regulator for controlling the terminal voltage of the shaft generator 1, and 19 is a controller for the synchronous phase adjuster 4. This is a voltage regulator that controls the terminal voltage.

Next, the operation of the above-described conventional shaft power generator will be described. The main engine 5 drives the propeller 6 and also drives the shaft generator 1 at the same time. Since the rotation speed of the main engine 5 changes according to the voyage state, the frequency of the AC power of the shaft generator 1 also changes. Therefore, the AC is once converted into DC by the converter 2 and then converted into AC power of a constant frequency by the inverter 3. Synchronous phase adjuster 4 supplies reactive power to inverter 3 and load 7 to keep the voltage of bus 9 constant. The obtained power of the constant frequency and constant voltage is supplied to the load 7 through the bus 9 through the circuit breaker 8.

[0005] The converter 2 and the inverter 3 are usually
It is composed of a power conversion element such as a CR, and is housed in a control panel as a power conversion circuit. Further, in order to reduce the size of the control panel, the power conversion circuit normally performs forced cooling with a fan.

[0006]

However, when the forced cooling fan fails for some reason and the cooling fan stops,
Because the power converter may be damaged by the temperature rise,
A protection circuit for stopping the shaft power generator after a certain time is provided. Generally, during voyage, electric power in the ship is supplied by the shaft power generator, and before the shaft power generator is stopped, the diesel power generator in the onboard equipment is started to prevent blackout.

FIG. 6 shows a configuration diagram of a conventional cooling device for a power conversion circuit. In the figure, 30 is a power conversion element with cooling fins, 31 is an intake port, 32 is an exhaust port, 33 is a forced cooling fan, 34 is a wind speed sensor, and 35 is a power converter panel containing the above-described components. is there. In the cooling device of the conventional power conversion circuit, the normal wind speed sensor 34 determines whether the forced cooling fan 33 is operating normally.

Next, FIG. 7 shows a flow chart when the power is switched from the conventional shaft power generator to the diesel power generator. As shown in this figure, when the forced cooling fan fails, a start command is issued to a diesel generator (hereinafter referred to as D / G), and after completion of the D / G start, synchronous driving with the shaft generator is performed. However, the shaft power generator is provided with a timer for a fixed period of time after the failure of the cooling fan to stop the shaft power generator.
In addition, in order to extend the timer time for the purpose of completely performing the synchronization, it is necessary to increase the element capacity of the power converter, which increases the cost and the size of the power converter.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a method for determining whether a failure occurs in a cooling fan of a power conversion element while a ship is powered only by a shaft power generator during a voyage. Another object of the present invention is to provide a cooling device for a power conversion device that can start a D / G and supply power onboard without blackout when ventilation is hindered and airflow is insufficient.

[0010]

According to a first aspect of the present invention, there is provided a cooling device for a power converter, wherein the cooling device for a power converter is forcibly cooled by a fan for cooling the power converter. In a shaft-driven power generator, a temperature detection element that detects a rise in temperature of a power conversion element, a temperature-voltage conversion circuit that converts the detected temperature to a voltage, and an operable time of the power conversion apparatus based on the detected temperature. And a signal output circuit for stopping the shaft drive generator by an output signal of the function circuit.

According to a second aspect of the present invention, there is provided a cooling device for a power conversion device, wherein an AC or DC of a power conversion element is provided in a main engine shaft drive generator for a marine vessel which is forcibly cooled by a fan for cooling the power conversion device. A current detection circuit for detecting the current of the current, a current-voltage conversion circuit for converting the detected current to a voltage, a current function circuit for setting the operable time of the power converter to a time limit characteristic by the detected current, And a signal output circuit for stopping the shaft drive generator by an output signal of the function circuit.

According to a third aspect of the present invention, there is provided a cooling device for a power conversion device, wherein a DC power of a power conversion element is detected in a marine machine main shaft drive power generation device forcibly cooling with a fan for cooling the power conversion device. A power detection circuit, a power-to-voltage conversion circuit that converts the detected power to a voltage, a power function circuit that sets the operable time of the power converter to a time limit characteristic based on the detected power, and an output of the power function circuit. And a signal output circuit for stopping the shaft drive generator by a signal.

According to a fourth aspect of the present invention, in the cooling device for a power converter according to the first, second, or third aspect, the temperature function circuit, the current function circuit, or the power function circuit for setting the time limit characteristic is set to , A microcomputer or an analog circuit.

According to a fifth aspect of the present invention, there is provided a cooling device for a power conversion device, comprising: a wind speed sensor for detecting a fan operation in a marine machine main shaft drive power generation device forcibly cooling with a fan for cooling the power conversion device. And a compressor for compressing air into the tank during the operation of the fan and discharging the compressed air when the fan stops to cool the tank forcibly.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a circuit configuration diagram of a first embodiment (corresponding to claim 1) of the present invention, and the same circuit configurations as those of the conventional example of FIG.

In FIG. 1, a power conversion element 30 and a temperature detection element 36 for detecting an increase in the temperature of the power conversion element 30 are provided in a power conversion panel (tank) 35 provided with an intake port 31 and an exhaust port 32. , A forced cooling fan 33 and a wind speed sensor 34 are provided. In addition, outside the power converter panel 35, a temperature-voltage conversion circuit 37 that converts the temperature detected by the temperature detection element 36 into a voltage, and sets the operable time of the power converter to the time limit characteristic based on the detected temperature. And a signal output circuit 39 for stopping the shaft drive generator by an output signal of the function circuit.

Next, the operation of this embodiment will be described.
When the forced cooling fan 33 stops for some reason, the wind speed sensor 34 detects that the fan has stopped or that the air volume has been blocked. The temperature detected by the temperature detection element 36 is converted into a voltage by a temperature-voltage conversion circuit 37, and the output voltage of the temperature-voltage conversion circuit 37 is input to a temperature function circuit 38. Temperature function circuit 38 according to the input voltage
Have a time limit characteristic set in advance to be equal to or less than the operable time allowed by the temperature of the power conversion element 30.

The above characteristics can be summarized as shown in FIG. That is, FIG. 2 shows the operation time T (vertical axis) with respect to the element temperature Ta (horizontal axis), and shows the time limit characteristic according to the element temperature Ta which is the output characteristic of the temperature function circuit 38. Therefore, by detecting the temperature of the element, not only a conventional fixed time timer but also a timer having a time limit characteristic based on the degree of temperature rise is provided. Note that 30
Is an allowable characteristic curve of the power conversion element.

FIG. 3 is a flowchart when the power is switched from the shaft power generator to the diesel power generator according to the present invention.
Normally, the shaft generator is not operated at full capacity during the voyage, and the load is selectively cut off when the shaft generator is abnormal. Therefore, since the timer time is set according to the degree of temperature rise of the element due to the change of the ambient temperature and the load condition of the shaft power generator, the element can be protected before the shaft power generator stops, and the power supply can be switched smoothly. .

Next, a second embodiment (corresponding to claim 2) of the present invention will be described. Although not specifically shown,
A current element is detected in place of the temperature element of the first embodiment, and the operation time is set to the time limit characteristic by the current element.

In the present embodiment, instead of detecting the element temperature of the power conversion element in the first embodiment, the alternating current of the power conversion element,
Or a current detection circuit for detecting a DC current, a current-voltage conversion circuit for converting the detected current to a voltage, a current function circuit for setting the operable time of the power converter to the time limit characteristic by the detected current, It comprises a signal output circuit for stopping the shaft drive generator by an output signal of the current function circuit.

In this embodiment, as in the first embodiment,
Since the timer time is set according to the current change and the current level due to the load condition of the shaft power generator, the elements can be protected before the shaft power generator stops, and the power supply can be switched smoothly.

Next, a third embodiment (corresponding to claim 3) of the present invention will be described. Although not specifically shown,
A power element is detected in place of the temperature element of the first embodiment, and the operation time is set to the time limit characteristic by the power element.

In this embodiment, instead of detecting the element temperature of the power conversion element in the first embodiment, a power detection circuit for detecting the DC power of the power conversion element, and a power-voltage for converting the detected power to a voltage. It comprises a conversion circuit, a power function circuit that sets the operable time of the power conversion device to the time limit characteristic based on the detected power, and a signal output circuit that stops the shaft drive generator by an output signal of the power function circuit. is there.

In this embodiment, similarly to the above-described first embodiment,
Since the timer time is set according to the power change and the power level due to the load condition of the shaft power generator, the elements can be protected before the shaft power generator stops, and the power supply can be switched smoothly.

Next, a fourth embodiment (corresponding to claim 4) of the present invention will be described. Although not specifically shown,
In this embodiment, the temperature, current, and power function circuits set for the time limit characteristics in the cooling device of the power converter described in the first, second, and third embodiments are a microcomputer or an analog circuit. .

FIG. 4 is a circuit configuration diagram of a fifth embodiment (corresponding to claim 5) of the present invention. The same circuit configurations as those of the conventional example of FIG. In the figure, a power conversion element 30, a forced cooling fan 33, and a wind speed sensor 34 are installed in a power converter panel (tank) 35 provided with an intake port 31 and an exhaust port 32. Further, a compressor 40 is installed outside the power converter panel 35, and a pipe 42 for cooling the power conversion element 30 with air through an air output adjustment solenoid valve 41 is disposed below the power conversion element 30. I have.

Next, the operation of this embodiment will be described.
The compressor 40 has sufficiently compressed air in the air tank, and the electromagnetic valve 41 is selected by the wind speed sensor 34 so as to be opened when the fan stops. When the forced cooling fan 33 stops for some reason, the fan speed is detected by the wind speed sensor 34. The electromagnetic valve 41 is opened by the fan stop signal, and the air stored in the compressor 40 through the pipe 42 flows out to cool the power conversion element 30. The tank capacity of the compressor 40 is determined by the size of the power converter board 35 and the amount of cooling air, and the D / G shown in FIG.

According to the present embodiment, the diesel generator is started even when the cooling fan of the power conversion element fails while the power supply on the ship is supplied only by the marine shaft power generator, and no blackout occurs. It is possible to provide a cooling device for a power conversion circuit capable of supplying an inboard power supply.

[0030]

As described above, the present invention (Claim 1)
According to the fourth aspect of the present invention, the timer time has a time limit characteristic depending on the degree of temperature rise of the element due to a change in the ambient temperature of the power converter, a load condition of the shaft power generator, and the like. The capacity allowed by the element can be fully used,
The elements can be protected before the shaft power generator stops, and the power supply can be switched smoothly.

According to the present invention (corresponding to claims 2 to 4), the timer time is set according to the degree of current or power due to changes in the current or power of the power converter and the load condition of the shaft power generator. Therefore, the elements can be protected before the shaft power generator stops, and the power supply can be switched smoothly.

According to the present invention (corresponding to claim 5),
When the ship's power is supplied only by the cruise shaft generator, the diesel generator can be started even if the cooling fan of the power conversion element fails, and the ship's power can be supplied without blackout. It works.

[Brief description of the drawings]

FIG. 1 is a circuit diagram of a first embodiment (corresponding to claim 1) of the present invention.

FIG. 2 is a diagram showing a time limit characteristic according to an element temperature, which is an output characteristic of the temperature function circuit according to the present invention.

FIG. 3 is a flowchart at the time of power supply switching from the shaft power generator to the diesel power generator according to the present invention.

FIG. 4 is a circuit diagram of a fifth embodiment (corresponding to claim 5) of the present invention.

FIG. 5 is a circuit configuration diagram of a conventional general shaft power generator.

FIG. 6 is a configuration diagram of a conventional cooling device for a power conversion circuit.

FIG. 7 is a flowchart at the time of switching power supply from a conventional shaft power generator to a diesel power generator.

[Explanation of symbols]

1 ... shaft generator, 2 ... converter, 3 ... inverter, 4 ...
Synchronous phase adjuster, 5: Main engine, 6: Propeller, 7 ...
Load: 8: Circuit breaker, 9: Bus, 10: Output frequency command setting device, 11: Output frequency detector, 12: Frequency controller,
13 current limiter, 14 current detector, 15 current controller, 16 phase controller, 17 phase controller, 18 voltage regulator, 19 voltage regulator, 30 power conversion element, 3
1 ... intake port, 32 ... exhaust port, 33 ... forced cooling fan,
34 wind speed sensor 35 power converter panel 36 temperature detecting element 37 temperature-voltage conversion circuit 38 temperature function circuit 39 signal output circuit 40 compressor 41
Solenoid valve, 42 ... piping.

Claims (5)

[Claims] A marine main shaft drive power generator forcibly cooling with a fan for cooling a power converter,
A temperature detection element for detecting a rise in temperature of the power conversion element, a temperature-voltage conversion circuit for converting the detected temperature to a voltage, and a temperature function circuit for setting the operable time of the power conversion apparatus to the inverse time characteristic based on the detected temperature And a signal output circuit for stopping the shaft drive generator by an output signal of the function circuit. 2. A main shaft drive power generator for a marine vessel, which is forcibly cooled by a fan for cooling the power converter,
A current detection circuit that detects the AC or DC current of the power conversion element, a current-voltage conversion circuit that converts the detected current to a voltage, and sets the operable time of the power conversion device to the inverse time characteristic based on the detected current. And a signal output circuit for stopping the shaft drive generator based on an output signal of the current function circuit. 3. A main shaft drive generator for a marine vessel, which is forcibly cooled by a fan for cooling the power converter,
A power detection circuit for detecting the DC power of the power conversion element, a power-to-voltage conversion circuit for converting the detected power to a voltage, and a power function circuit for setting the operable time of the power conversion device to the infinite time characteristic by the detected power And a signal output circuit for stopping the shaft drive generator by an output signal of the power function circuit. 4. The method according to claim 1, 2 or 3.
The cooling device for a power conversion device according to any one of the preceding claims, wherein the temperature function circuit, the current function circuit, or the power function circuit that sets the time limit characteristic is configured by a microcomputer or an analog circuit. 5. A main shaft drive generator for a marine vessel, which is forcibly cooled by a fan for cooling the power converter,
A wind speed sensor that detects a fan operation, and a compressor that compresses air into a tank during the operation of the fan and discharges the compressed air when the fan is stopped to forcibly cool the fan. Cooling system.