JPH0813199B2 - Rotation control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a rotation control device, in particular, a rotation speed detection signal detected from the prime mover side as a rotation detection signal in controlling the rotation speed of a prime mover at a constant speed. And a fail-safe circuit that determines which of the two detection signals, the voltage detection signal as the rotation detection signal detected from the generator side, is preferentially used as the rotation detection signal. .

(Prior art) Conventionally, in a generator system, a governor control device is provided to keep the rotation speed of the prime mover constant, and the governor control device keeps the rotation speed of the prime mover constant even when the generator load fluctuates. However, an automatic control system that keeps the frequency of the generator constant is used.

Conventionally, a mechanical type governor control device has been used, but recently, an electronic type governor control device has been used.

In the electronic governor control device used in the conventional engine-generator device, the number of rotation detection signals for controlling the rotation speed is usually limited to one.

(Problems to be Solved by the Invention) When there is only one rotation detection signal for rotation speed control as in the past, when this detection signal becomes abnormal, the rotation speed of the prime mover rises, causing a runaway. .

Therefore, in the engine generator system, rotation detection is performed on the prime mover side and the generator side respectively, and the detection signal on either side is prioritized, and when an abnormality occurs on the priority detection signal side, the other detection is performed. There is a demand for a dual-structure rotation control that controls the rotation speed of a prime mover by a signal to control the rotation speed of the prime mover at a constant level and prevents runaway of the prime mover.

The present invention has been made in view of the above points, and does not have a double detection circuit configuration that detects the number of revolutions of the prime mover from the prime mover side and the generator side, respectively. The detection signal is prioritized, and when an abnormality occurs on the generator side, the detection signal on the prime mover side is used to prevent runaway of the prime mover in advance, and the rotation speed of the prime mover is always controlled at a constant speed. It is an object of the present invention to provide a fail-safe circuit that determines the priority order of rotation detection signals so that the rotation of a prime mover does not rise abnormally.

(Means for Solving Problems) Therefore, the rotation control device of the present invention is provided with a governor control device, and in the engine generator device in which the constant speed rotation control of the prime mover is performed, the governor control device is configured to change the rotation speed of the prime mover. A voltage detection circuit and a rotation speed detection circuit for respectively detecting the voltage and the rotation speed, a fail-safe circuit for prioritizing a detection signal of either the voltage detection circuit or the rotation speed detection circuit as a rotation detection signal, and a prime mover. The weight of the load of
A gain automatic adjustment circuit that changes the gain of the control system according to the weight, a PID adjuster that creates a PID control signal based on the output obtained from the gain automatic adjustment circuit, and the PI
A PWM circuit unit that converts the output of the D regulator into a pulse width control signal, an actuator that controls the rotation of the prime mover according to the PWM signal output by the PWM circuit unit, and a positive / negative bipolar power source for each circuit unit. And a switch circuit for turning on / off the rotation detection signal detected by the rotation speed detection circuit, and a voltage detection signal for controlling the switch circuit in the fail-safe circuit. When an abnormality occurs in the prioritized voltage detection signal system, a priority circuit that turns on the switch circuit to prioritize the rotation speed detection signal and an inflow of the rotation detection signal to the voltage detection signal side are given priority. A reverse current blocking diode for blocking, and a signal line of a voltage detection signal flowing through the reverse current blocking diode and a signal of a rotation speed detection signal flowing through the switch circuit. It is characterized in that it is provided with a circuit connected to a wire. An embodiment of the present invention will be described below with reference to the drawings.

(Embodiment) FIG. 1 shows the configuration of an embodiment of a fail safe circuit of a rotation control device according to the present invention, and FIGS. 2 (A) and 2 (B) show the first embodiment.
Another example of the configuration of the priority circuit shown in FIGS. 3 and 4 is another example of the configuration of the fail-safe circuit of the rotation control device according to the present invention, and FIG. 5 is a failure of the rotation control device according to the present invention. -The figure shows an example configuration of an engine generator device in which a safe circuit is used.

Before describing the fail-safe circuit of the rotation control device according to the present invention in FIGS. 1 to 4, the outline of automatic control of the prime mover in the engine generator by the governor control device will be described with reference to FIG. To explain.

In FIG. 5, reference numeral 1 is an engine generator, 2 is a rotation speed detection circuit, 3 is a voltage detection circuit, 4 is a fail safe circuit, 5 is an automatic gain adjustment circuit, 6 is a PID regulator, 7 is an amplifier, 8 Is a PWM circuit unit, 9 is an actuator, and 10 is a power supply device.

From the prime mover or the generator side of the engine generator 1, the load fluctuation or the rotation fluctuation of the engine generator 1 due to some cause
The rotation speed detection circuit 2 and the voltage detection circuit 3 detect the voltage individually. As for the rotation speed detection signal detected by the rotation speed detection circuit 2 and the voltage detection signal detected by the voltage detection circuit 3, one of the detection signals, for example, the voltage detection signal is preferentially detected by the fail safe circuit 4. It is selected as the rotation detection signal of the engine generator 1. The other rotation speed detection signal is replaced with the voltage detection signal obtained from the voltage detection circuit 3 when an abnormality occurs in the voltage detection circuit 3 system, and the rotation speed detection signal obtained from the rotation speed detection circuit 2 fails. -Selected by the safe circuit 4 to prevent the occurrence of abnormal rotation such as runaway of the prime mover. The automatic gain adjusting circuit 5 detects the light weight of the current load, that is, the weight from the output of the power generator 1 and determines the gain of the control system according to the weight of the load. Then, the fail safe circuit 4 is set so that the gain of the system is set to this determined value.
The detection signal selected from, that is, the voltage detection signal is amplified. Subsequently, the PID adjuster 6 minimizes the residual deviation between the target value and the final value, that is, the steady-state error, and changes the response to a control signal that should quickly follow the rotational fluctuation. The control signal is amplified by the amplifier 7 and further converted by the PWM circuit 8 into a PWM signal. The actuator 9 of the rotary encoder is controlled by the PWM signal, and the rotation speed of the prime mover in the engine generator 1 is controlled to be constant depending on the angle output by the actuator. A positive / negative bipolar power supply voltage is supplied from the power supply device 10 to each circuit unit.
A positive / negative control angle signal for positively or negatively rotating the rotary encoder of the actuator 9 in accordance with the pulse width of the PWM signal by a positive / negative voltage supplied from the power supply device 10 to keep the rotational speed of the prime mover constant. Is getting

Next, the fail-safe circuit of the rotation control device according to the present invention will be described with reference to FIG.

In FIG. 1, reference numeral 12 is a priority circuit, 13 is a switch circuit, 14 is a reverse current blocking diode, 15 and 16 are operational amplifiers, 1
7, 18 are diodes, 19 is a variable resistor, 20 is a capacitor, and 21 to 24 are resistors.

The operational amplifier 15 operates as a comparator, and the variable resistor input to the non-inverting input terminal of the operational amplifier 15
The reference voltage from 19 and the voltage detection signal are compared. The reference voltage set by the variable resistor 19 corresponds to the rotation speed of the engine generator 1 which is determined in advance, and when the voltage detection signal is higher than the reference voltage, the operation and amplifier
The output of 15 becomes "L", and the non-inverting input terminal of the operational amplifier 16 of the switch circuit 13 becomes "L". That is, the priority circuit 12 controls the switch circuit 13 to be turned off, prioritizes the voltage detection signal, and outputs it as a rotation detection signal to the next-stage automatic gain adjustment circuit 5. On the other hand, when the voltage detection signal is lower than the reference voltage of the variable resistor 19, the operational amplifier 15
Output becomes "H" and the diode 17 is reverse biased. That is, the switch circuit 13 is controlled to be turned on, and the operation,
The rotation speed detection signal input to the non-inverting input terminal of the amplifier 16 via the resistor 23 is sent to the next-stage automatic gain adjustment circuit 5 as a rotation detection signal via the diode 18 instead of the voltage detection signal. At this time, the voltage detection signal is lower than the rotation speed detection signal, and it goes without saying that the reverse current blocking diode 14 is reversely biased, and the rotation speed of the engine generator 1 may be controlled according to the rotation speed detection signal. Needless to say.

As is apparent from this description, when the switch circuit 13 is turned on / off by the control of the priority circuit 12 and the voltage detection signal is lowered, the rotation speed detection signal has priority over the voltage detection signal and becomes the rotation detection signal, Further, in the vicinity of the steady rotation of the engine generator 1, the voltage detection signal becomes the rotation detection signal with priority over the rotation speed detection signal.

Therefore, when the voltage detection signal goes to zero or goes down abnormally due to a failure of the generator and the voltage detection circuit 3 system, it tries to increase the rotation of the prime mover in order to increase the output voltage of the generator. Therefore, the voltage detection signal of the voltage detection circuit 3 does not rise, the rotation of the prime mover rises more and more, and it tries to run away. However, if the voltage detection signal drops and drops below the reference voltage of the variable resistor 19, the priority circuit
12 turns on switch circuit 13, so-called failure
The safe works, and the rotation speed of the prime mover is controlled by the rotation speed detection signal that detects the rotation speed of the motor itself, and is controlled to a predetermined steady rotation speed.

Even if the voltage detection signal is not a perfect DC voltage, the capacitor 20 in the priority circuit 12 prevents the capacitor from being detected.
With the function of 20, the priority circuit 12 operates normally, and the fail safe operates.

FIGS. 2A and 2B show another example of the configuration of the priority circuit, which can be constituted by an open collector operation amplifier 25 as shown in FIG. 2A, and FIG. It is also possible to configure with the transistor 26 as described above. Reference numerals 19 to 22 in FIGS. 9A and 9B correspond to those in FIG. 1, 27 is a capacitor, and 28 is a resistor. Since the operation of these priority circuits is the same as that of FIG. 1, description thereof will be omitted.

FIG. 3 shows another embodiment of the fail-safe circuit. Reference numerals 12, 14 to 17, 19 to 23 correspond to those in FIG. Reference numeral 29 represents a switch circuit, and 30 represents a resistance. The configuration of the priority circuit 12 and the connection configuration of the reverse current blocking diode 14 shown in FIG. 3 are the same as those of FIG. 1, and among the configurations of the switch circuit 19, the operational amplifier 16 is included.
Is connected to the cathode side of the backflow prevention diode 14 via the resistor 30 and is used as a rotation detection signal. As a result, the number of constituent parts of the switch circuit 29 is reduced, and the performance is improved as compared with that of FIG. That is, the operation of the priority circuit 12 is the same as in the case of FIG.
The switch circuit 29 is turned on / off according to whether the voltage detection signal is higher or lower than the set voltage of the variable resistor 19. When the voltage detection signal is higher than the set voltage of the variable resistor 19, the non-inverting input terminal of the operational amplifier 16 becomes "L", and the output of the operational amplifier 16 becomes "L". The voltage detection signal is
Even if the allowable input voltage of the operational amplifier 16 is higher than the allowable input voltage due to, for example, pulsating current, the resistance 30 becomes a load of the voltage detection signal, and a high voltage detection signal is not input to the non-inverting input terminal of the operational amplifier 16. The input of the operational amplifier 16 is protected. When the voltage detection signal is lower than the set voltage of the variable resistor 19, the diode 17 is reverse biased and the switch circuit
29 is on. Therefore, the rotation speed detection signal is sent as a rotation detection signal from the operational amplifier 16 operating as a buffer amplifier to the next-stage automatic gain adjustment circuit 5 via the resistor 30. Since the resistance 30 is smaller than the impedance of the automatic gain adjustment circuit 5, the voltage drop due to the resistance 30 can be ignored.

FIG. 4 shows the construction of another embodiment of the fail-safe circuit, and the reference numerals 13 to 24 correspond to those of FIG. Reference numeral 31 is a priority circuit, 32 is a priority elimination circuit, 33 is an operational amplifier, 34 is a diode, and 35 is a variable resistor.

The priority circuit 31 has a priority cancellation circuit 32 newly added to the priority circuit 12 shown in FIG. 1. Except for the operation of the priority cancellation circuit 32, the same operation as in the case of the description of FIG. I do.

The priority elimination circuit 32 includes an operational amplifier 33, a diode 34, and a variable resistor 35, and the operational amplifier 33 operates as a comparator. The reference voltage is obtained from the set voltage of the variable resistor 35, and the reference voltage and the rotation speed detection signal are compared. And the rotation speed detection signal is variable resistance
When it is lower than the reference voltage based on 35, the output of the operational amplifier 33 becomes "H", the diode 34 is reverse biased, and the first
The same operation as the priority circuit 12 shown in the figure is performed. When the rotation speed detection signal becomes higher than the reference voltage based on the variable resistor 35, the inverting input terminal of the operational amplifier 15 is forcibly dropped to "L", and the switch circuit 13 is turned on.

Here, the reference voltage based on the variable resistor 19 is set to the number of revolutions of the prime mover N ₁ , and the reference voltage based on the variable resistor 35 is set to the number of revolutions of the prime mover N ₂ (N ₂ > N ₁ ) Rotation speed is set in advance.

Since the priority elimination circuit 32 does not operate until the number of revolutions of the prime mover becomes N ₁ , the same operation as in the case of FIG. 1 is performed as described above. When the generator and the voltage detection signal system fail and the voltage detection signal drops to zero or drops to zero, the voltage detection signal is lower than the reference voltage based on the variable resistor 19, so that the voltage detection signal detects rotation. It is sent as a signal to the next-stage automatic gain adjustment circuit 5, and the rotation speed of the prime mover starts to rapidly increase. Since the rotation speed detection signal for detecting the rotation speed of the prime mover rises in response to the increase in the rotation speed of the prime mover, when the rotation speed detection signal becomes higher than the reference voltage of the variable resistor 35, that is, the rotation of the prime mover The operation of the priority circuit 31 is canceled by the priority cancellation circuit 32 at the time when it rises to N ₂ . As a result, the switch circuit 13 is turned on, and the rotation speed detection signal is converted into a voltage detection signal and sent as a rotation detection signal to the next-stage automatic gain adjustment circuit 5. Therefore, the runaway of the prime mover is prevented, and the fail-safe operation is more excellent than that of the fail-safe circuit shown in FIG.

Also in the case of the configuration of FIG. 4, the configuration of the switch circuit 13 may be replaced with the switch circuit 29 of FIG. 3, and also in the configurations of FIGS. 3 and 4, the priority circuit of FIG. The circuit portion corresponding to 12 may be replaced with the configuration shown in FIGS.

(Effects of the Invention) As described above, according to the present invention, a fail-safe is established when the generator and the voltage detection circuit system are abnormal, and the runaway of the prime mover is prevented. Further, even if the voltage detection signal and the rotation speed detection signal are not DC, the rotation control of the prime mover can be performed. Further, in the configuration of the switch circuit shown in FIG. 3, since it is independent of the voltage detection signal system, the voltage detection signal is
It has the advantage that it can be used at a voltage higher than the allowable input value of the amplifier and that the number of parts used is small.

Furthermore, in the case of the configuration of FIG. 3, not only abnormal voltage drop,
The fail-safe operates even if the rotation speed is abnormally increased, ensuring more safety.

[Brief description of drawings]

FIG. 1 shows the configuration of an embodiment of a fail safe circuit of a rotation control device according to the present invention, and FIGS. 2 (A) and 2 (B) show another configuration example of the priority circuit of FIG. 1, FIG. FIG. 4 shows another embodiment of the fail-safe circuit of the rotation control device according to the present invention, and FIG. 5 shows one embodiment of an engine generator device using the fail-safe circuit of the rotation control device according to the present invention. An example configuration is shown. In the figure, 1 is an engine generator, 2 is a rotation speed detection circuit, 3 is a voltage detection circuit, 4 is a fail-safe circuit, 5 is an automatic gain adjustment circuit, 6
Is a PID regulator, 7 is an amplifier, 8 is a PWM circuit section, 9 is an actuator, 10 is a power supply device, 12 is a priority circuit, 13 is a switch circuit, 14 is a reverse current blocking diode, 15 and 16 are operational amplifiers, 17 , 18 is a diode, 19 is a variable resistor, 20 is a capacitor, 21 to 24 are resistors, 25 is an operational amplifier, 26 is a transistor, 27 is a capacitor, 28 is a resistor, 29 is a switch circuit, 30 is a resistor, 31 is a priority, 31 is a priority A circuit, 32 is a priority elimination circuit, 33 is an operational amplifier, 34 is a diode, and 35 is a variable resistor.

Claims (1)

[Claims] Claims: 1. A prime mover generator device comprising a governor control device for performing constant speed rotation control of a prime mover, wherein the governor control device detects a rotation speed of the prime mover by a voltage and a rotation speed, respectively. Number detection circuit, a fail-safe circuit that prioritizes the detection signal of either the voltage detection circuit or the rotation speed detection circuit as a rotation detection signal, and detects the weight of the load of the prime mover, and according to the weight Automatic gain adjusting circuit for changing the gain of the control system, a PID adjuster for creating a control signal for PID control based on the output obtained from the automatic gain adjusting circuit, and the output of the PID adjuster for the pulse width A PWM circuit unit for converting into a control signal, an actuator for controlling the rotation of the prime mover according to the PWM signal output by the PWM circuit unit, and a power supply device for supplying positive and negative bipolar power supplies to the respective circuit units, Further above The Eru-safe circuit,
A switch circuit that turns on / off the rotation detection signal detected by the rotation speed detection circuit, and a priority is given to the voltage detection signal by controlling the switch circuit. When an abnormality occurs in the priority voltage detection signal system, Is a priority circuit that turns on the switch circuit and prioritizes the rotation speed detection signal;
A reverse current blocking diode for blocking the inflow of the rotation detection signal to the voltage detection signal side, and a rotation speed detection signal flowing through the signal line of the voltage detection signal flowing through the reverse current blocking diode and the switch circuit. And a circuit connected to the signal line of the rotation control device.