JPH0468876B2 - - Google Patents

Description

8, in which the output voltage of the generator 1 is set to the forward conversion control section 7.
and a power-on reset circuit that monitors whether the power supply voltage rises to a predetermined value necessary to operate the power supply voltage and the inverse conversion control section 8, detects that the power supply voltage rises to the predetermined value, and issues a control signal. 17, the inverse conversion control section 8 includes an oscillation section 13 and a frequency dividing section 1.
4, a waveform shaping circuit 15, and a gate amplifier section 16, and a gate signal generation mechanism for generating the alternating voltage of a predetermined frequency, and the inverse conversion control section 8 is configured to perform the power-on reset. a first delay means 19 that is activated by a control signal of the circuit 17 to provide a predetermined delay time after the detection, and supplies the gate signal to the forward conversion circuit 3 when the predetermined delay time has elapsed; A flip-flop 18 is activated after the output is generated from the first delay means 19, and a predetermined delay time is given from the time of operation of the flip-flop 18, and the gate signal generation mechanism is started when the predetermined delay time has elapsed. a second delay means 20 for supplying a gate signal to the inverse conversion circuit 4.

[Detailed description of the invention]

The present invention provides a power supply device for a ship, in particular, includes a generator driven by a propulsion engine of a fishing boat, and converts the output from the generator using a forward conversion circuit and an inverse conversion circuit. In a marine power supply device that supplies alternating voltage with a constant frequency, the transition from the unstable rotational state at the initial startup stage of the engine to the stable rotational state is accurately extracted to ensure power supply to the load. The present invention relates to a marine power supply device designed to perform the following operations.

Conventionally, power supply equipment for ships, especially fishing boats, has been
It is equipped with a main generator driven by the main engine that drives the propulsion machine, and considering that the rotational speed of the main engine fluctuates greatly due to full speed operation, it is equipped with a relatively small capacity auxiliary engine. The engine was equipped with an auxiliary generator driven by the auxiliary generator, and when operating at full speed, the auxiliary generator used power with a stable frequency. However, providing an auxiliary engine and an auxiliary generator in addition to the main generator as described above increases not only equipment costs but also fuel costs as a regular expense.

In order to solve this problem, we focused on the fact that the need to provide an auxiliary generator was due to the frequency fluctuation of the main generator, so we first converted the output of the main generator to DC through a forward conversion circuit, and then converted it inversely. A system for generating a constant frequency alternating voltage through a circuit has been considered and previously filed by the inventors of the present application.

Even in such an improved system, the frequency of the alternating voltage is kept constant by, for example, an oscillator, but although the generator itself is equipped with a voltage regulation circuit, it There remains the problem that the engine speed fluctuates greatly when the clutch is engaged or disengaged, causing a temporary drastic change in the output voltage of the generator.

FIG. 1 conceptually shows how the generator rotational speed (engine rotational speed) and the generator output voltage change in accordance with the operating mode of a fishing boat.

In other words, in response to the start of the engine, the number of rotations of the generator increases, and an induction motor, for example, is used for loading, etc., and the fishing boat itself starts, speeds up, sails, and arrives at the fishing spot.・In response to operating conditions such as operation, return trip, speed increase, and navigation,
Although the output voltage of the generator fluctuates greatly temporarily,
As is clear from the figure, the output voltage of the generator fluctuates significantly, particularly when the engine is started, that is, when the fishing boat is started.

In this way, when the fluctuation in the output voltage of the generator is particularly large, that is, when the engine is started, if a gate signal is supplied to the forward conversion circuit and the inverse conversion circuit at the same time as the engine starts, the forward conversion circuit will be connected to the DC line. Charging of the upper capacitor and power supply to the load side of the inverter are performed at the same time, which increases the power capacity required for the forward conversion circuit, and if the power capacity is not large enough, the DC voltage will drop. There was a problem that undesirable operation occurred and in some cases, commutation failed.

For this reason, in the case of the present invention, in consideration of fluctuations in the output voltage of the generator at the time of engine startup,
After a certain period of time has elapsed after the output voltage of the generator reaches a predetermined value, for example, 200V or more, the forward conversion circuit is first put into operation, and then, after a certain period of time has elapsed, the inverse conversion circuit is put into operation and turned off. Commutation failure of the inverse conversion circuit is prevented from occurring as desired.

FIG. 2A and FIG. 2B together constitute one figure, and show the configuration of one embodiment of the present invention.

In the figure, numeral 1 is a generator driven by the engine, 2 is a circuit breaker, 3 is a forward conversion circuit, 4 is an inverse conversion circuit, 5 is a load output circuit terminal,
Reference numeral 6 represents a power supply section, 7 a forward conversion control section, and 8 a reverse conversion control section. In addition, G ₁ to G ₆ are the thyristor gates (or gate terminals) in the forward conversion circuit,
G _A to G _F each represent a thyristor gate (or gate terminal) in the inverse conversion circuit.

The output voltage from the generator 1 is converted into a DC voltage by a forward conversion circuit 3, and then converted into a DC voltage by a reverse conversion circuit 4.
The voltage is converted into a constant frequency alternating voltage by the converter, and is supplied to the load. On the other hand, the output voltage of the generator 1 is led to a power supply unit 6, and the power supply unit 6 generates, for example, constant voltages of +6V, ground, and -6V.
The forward conversion control section 7 supplies a power supply voltage to the inverse conversion control section 8 .

Although not shown, the forward conversion control unit 7 is supplied with voltages of +6V, ground, and -6V from the power supply unit 6, enters the operating state, and receives signals r, s, and t for detecting phase rotation. Then, a signal is supplied to the thyristor gates _G1 to _G6 in the forward conversion circuit. Further, the inverse conversion control unit 8 is supplied with voltages of +6V and ground -6V from the power supply unit 6 and enters the operating state, although detailed illustrations are omitted, and the inverse conversion circuit thyristor gate G _A or supply a signal to _GF .

In the power supply section 6, the voltage reduced by the transformer 9 is rectified by the rectification section 10 and guided to the power supply voltage generation unit 11,
+6V regulated by 2, ground, -
6V is generated.

In the inverse conversion control section 8, the oscillation section 13,
A gate signal generation mechanism consisting of a frequency dividing section 14, a waveform shaping circuit 15, and a gate amplifier section 16 is provided. The gate signal generating mechanism generates and supplies signals to the gates G _A to GF as described above, but in the illustrated embodiment, the signals are generated and supplied to the gates G A to G _F in response to a predetermined operating state of the power supply voltage generating unit 11. The activated power-on reset circuit 17, first delay circuit 19, and flip-flop 18 send a signal to the forward conversion control unit 7 to start its operation after a predetermined time has elapsed after the voltage generated by the generator 1 has risen to a predetermined value. The gate of forward conversion circuit 3
A signal is generated and supplied to G ₁ to G ₆ , and then, after a predetermined time has elapsed by the second delay circuit 20 , the signal is applied to the waveform shaping circuit 15 , and the gate amplifier section 16 generates and supplies the signal to the gate G _A to G 6 . It is designed to generate and supply signals to _F. Furthermore, the reverse conversion control section 8 is also provided with a voltage abnormality detection section 22 and a reverse phase/open phase control section 23 to detect an abnormal state in the system, and the breaker/trip control section 24 detects the abnormal state. It has a configuration that interrupts the circuit breaker 2 described above.

The operation of such a marine power supply device will be further explained below.

That is, an operational amplifier 25 is provided in the power supply voltage generation unit 11, and the voltage division level created by resistors 26 and 27 is compared with the reference voltage level created by resistor 28 and Zener diode 29. Then, when the output voltage of the generator 1 rises to a predetermined value, that is, 200V as shown in FIG.
level. As a result, the transistor 31 is turned on through the Zener diode 30, the transistor 33 is turned on through the photocoupler 32, and the transistor 35 is turned on through the photocoupler 34. By turning on the transistors 33 and 35 together, +6V, which is regulated by the constant voltage circuit 12, the ground, and -
6V is output, and this is supplied as the power supply voltage necessary to operate the forward conversion control section 7 and the inverse conversion control section 8. At the same time, the power-on reset circuit 1 constitutes the voltage detection means according to the present invention.
7 detects this and operates, and the control signal, that is, the output signal it generates is input to the flip-flop 18 and the first delay circuit 19. Then, the first
The delay circuit 19 applies a signal to the flip-flop 18 after a predetermined time, for example, 13 seconds, and the outputs of the output terminals 18A and 18B of the flip-flop 18 become high level, causing a forward conversion pulse start signal to be output from the terminal 18B. As described above, since the predetermined power supply voltage is already supplied to the forward conversion control section 7, the forward conversion control section 7 starts the forward conversion circuit 3 by inputting the above-mentioned forward conversion pulse start signal.
generates gate signals corresponding to the gates _G1 to _G6 , and supplies the gate signals to the circuit 3. Therefore, the forward conversion circuit 3 enters the operating state. (but,
At this point, the inverse conversion circuit 4 has not yet entered the operating state, and power is not being supplied to the load. )
At the same time, a signal is supplied from the output terminal 18A to a second delay circuit 20 constituting the second delay means according to the present invention, and when a predetermined period of time, for example, 2 seconds has elapsed, the output of the circuit 20 is sent to the waveform shaping circuit 15. The gate amplifier section 16 outputs a pulse signal, that is, a gate signal, corresponding to the gates G _A to _GF of the inverse conversion circuit 4 , and the gate signal is input to the inverse conversion circuit 4 .
supply to. This causes the inverse conversion circuit 4 to enter the operating state. As described above, since the forward conversion circuit 3 has already started operating, the power supply from the generator 1 to the load is started for the first time when the inverse conversion circuit starts operating. And in this case,
Since the forward conversion circuit 3 and the inverse conversion circuit 4 are in a sufficiently stable operating state and have good overload characteristics, commutation failure does not occur.

In short, the forward conversion control unit ₇
After generating the signal corresponding to _G6 , the forward conversion control unit 8 generates a signal corresponding to the gates G _A to G _F , so that after the forward conversion circuit 3 starts operating and becomes stable, the inverse conversion circuit 4 starts operating. This ensures that the power supply to the load starts when the power supply starts operating.

The operational amplifier 25 also includes resistors 36 and 3.
A feedback circuit consisting of 7 is provided. This gives a hysteresis characteristic to the characteristics of the operational amplifier 25, and once the output of the amplifier 25 reaches a high level, the output voltage of the generator 1, for example,
Only when the voltage drops below 120V is the output of the amplifier 25 set to low level. amplifier 25
The state in which the output of the amplifier 25 becomes low level corresponds to the case where the engine that drives the generator 1 stops rotating, and when the output of the amplifier 25 becomes low level, the transistor 31 is turned off, and then the transistors 33 and 35 are turned off. is turned off and the output voltage +6V, ground, and -6V are eliminated. As a result, the operation of the forward conversion circuit 3 and the inverse conversion circuit 4 is stopped, and power supply to the load is stopped. In this case, the output voltage of the generator 1 is
When the voltage rises to 200V or more, the power-on reset circuit 17 detects this again, and as described above, the forward conversion circuit 3 and the inverse conversion circuit 4 are activated in sequence to supply power to the load.

In addition, the above-mentioned power supply voltage generation unit 11 includes:
A terminal VV is provided for extracting a voltage corresponding to the peak level of the output voltage of the generator 1. The voltage at the terminal VV is monitored by the voltage abnormality detection section 22 as described later. That is, the output voltage of the generator 1 is 200V or more as shown in Figure 1.
If it is within the range of 240V (in the same figure), it is considered to be in a normal operating state, and the output voltage of generator 1 exceeds that range and falls within the range of 180V to 255V (in the same figure). In either case, the voltage abnormality detection unit 2
2 does not detect any abnormality and works to keep the voltage as constant as possible by the voltage adjustment function of a phase control circuit (not shown) provided in the forward conversion control section 7.

When the output voltage of the generator is within a range exceeding the range shown in Figure 1, the condition is, for example, 2.
If it persists for more than a second, it is detected as a failure. That is, the voltage of the terminal VV mentioned above is detected by the voltage abnormality detection section 2.
2. The operational amplifier 38 in the voltage abnormality detection section 22 compares the voltage at the terminal VV with a reference level, which is the voltage dividing point of the resistor 39, and changes the output to a high level when the output voltage of the generator 1 decreases to, for example, 180V or less. Make it. If this high level state continues for more than 2 seconds, the capacitor 40
voltage becomes equal to or higher than a predetermined level.

In addition, an operational amplifier 4 is included in the voltage abnormality detection section 22.
1 is provided. The amplifier 41 includes a resistor 42
The voltage at the terminal VV is compared with a reference level, which is a voltage division point, and when the output voltage of the generator 1 rises to, for example, 255V or more, the output is set to a high level. and,
If this high level state is maintained for 2 seconds or more, for example, the voltage of the capacitor 43 becomes equal to or higher than a predetermined level.

Voltage of the capacitor 40 or capacitor 4
When the voltage of the circuit 3 reaches a predetermined level or higher, the output of the operational amplifier 44 becomes high level, and the breaker trip control unit 24 is activated. That is, the circuit breaker 2 described above is shut off.

An operational amplifier 45 is also provided within the voltage abnormality detection section 22 . The amplifier 45 includes a resistor 4
When the output voltage of the generator 1 becomes, for example, 360 V or higher, the output of the amplifier 45 immediately becomes a high level, and the breaker trip controller 24 is activated. It is activated and causes circuit breaker 2 to shut off.

As explained above, according to the present invention, in an operating state with severe voltage fluctuations as explained with reference to FIG. , that is, the rise in the output voltage of the generator to a predetermined value, for example, 200V, first, supply a gate signal to the forward conversion circuit to operate the forward conversion circuit and convert it to a stable DC voltage. condition, and then supplies a gate signal to the inverse conversion circuit. Therefore, commutation failure of the inverse conversion circuit in the initial state where the output level of the generator is unstable can be prevented, and the load This ensures that power is supplied to the

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram illustrating the state in which the rotational speed of the generator and the output voltage of the generator change depending on the operating state of the fishing boat, and Fig. 2 A and B show the configuration of an embodiment of the present invention. FIG. In the figure, 1 is a generator, 2 is a circuit breaker, 3 is a forward conversion circuit, 4 is an inverse conversion circuit, 5 is a load output terminal, 6 is a power supply section, 7 is a forward conversion control section, and 8 is an inverse conversion control section ,
11 is a power supply voltage generation unit, 12 is a constant voltage circuit, 13 is an oscillation section, 14 is a frequency division section, 15 is a waveform shaping circuit, 16 is a gate amplifier section, 17 is a power-on reset circuit, and 19 is a first delay circuit. , 20 represents a second delay circuit.

Claims (1)

[Claims] 1. A generator 1 that is driven by a marine propulsion engine and whose output voltage is controlled by a voltage adjustment circuit; a forward conversion circuit that rectifies the output voltage from the generator 1; 3. An inverse conversion circuit 4 that obtains a predetermined alternating voltage from the output of the forward conversion circuit 3; a forward conversion control 7 that performs control including supplying gate signals to the forward conversion circuit 3; and a gate signal for the inverse conversion circuit 4. A reverse conversion control section 8 that performs control including supply, and the forward conversion control section 7 and the reverse conversion control section.