JP2012050294A - Control system for power generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the increase in a size and a cost of a power generator and a prime mover for driving a power generator, and to shorten a battery charging time and reduce the fuel consumption of the prime mover, and thereby, to improve an economic effect and an environment improvement effect.SOLUTION: A hybrid-connection power source consists of a battery 1 and a power generator 5 for charging the battery 1. A power is supplied to a propulsive motor 12 and an auxiliary machine 33 from the power generator 5 while charging the battery 1. A charging change-over switch 19 is provided. At operation of supplying a power, any one of three kinds of charging systems of a constant voltage charging system, a constant current charging system, and a constant power charging system is selected and executed by this switch 19.

Description

  The present invention relates to an electric propulsion system for supplying electric power to a propulsion motor and an auxiliary machine while charging the battery by the generator, particularly a control of the generator, in a hybrid power source composed of a battery and a generator for charging the battery. Regarding the method.

In the operation mode of an electric propulsion system, such as an electric propulsion ship, equipped with a hybrid power source composed of a battery and a generator for charging the battery, power is supplied to the propulsion motor and auxiliary equipment while charging the battery with the generator. There are two modes: a mode in which the generator is operated and a mode in which the generator is stopped and only the battery is operated.
In the former mode of driving while charging the battery with the generator, the battery charge capacity and the generator output capacity are closely related, and if the battery capacity increases, the generator capacity increases and the generator is driven. The capacity of the prime mover (the prime mover for driving the generator) is also increased.

That is, if the battery capacity increases as the electric propulsion system powers up, the generator capacity increases, and the capacity of the motor for driving the generator increases, resulting in an increase in size and cost due to an increase in the size and mass of the generator and motor. Occurs.
As a battery of an electric propulsion system equipped with a battery, a lead battery has been used conventionally, but in recent years, adoption of a lithium ion battery having a high energy density has been studied. Since the generator capacity is governed not only by the capacity of the battery but also by the charging characteristics, if the capacity of the lead battery and the lithium ion battery is the same, even if the lead battery cannot charge a large current, the lithium ion battery Then, since a large current charge is possible, it will also contribute to an increase in generator capacity.

Also, according to the conventional lead-acid battery charging method, it is common to charge with a large current at the beginning of charging, a medium current at the middle of charging, and a small current at the end of charging, and this is caused by a charging operation. A charging method that suppresses the electrolysis action of the electrolyte (by generating hydrogen gas and oxygen gas) and reduces charging power loss is required, so it takes a long time to fully charge a lead battery. .
On the other hand, since the lithium ion battery does not have an electrolyte solution, no gas is generated and the internal loss of the battery is small, so that it can be charged with a large current until just before full charge. As a result, lithium ion batteries are expected to significantly shorten the charging time compared to lead batteries.

However, large current charging, which is a feature of lithium-ion batteries, increases the capacity of the generator, which increases the size of the generator and raises the cost of the generator. In addition, the motor that drives the generator (generator drive) The same problem arises for the motor). Such an increase in the size of the generator and the prime mover for driving the generator is a very serious problem in an electric propulsion system such as an electric propulsion ship having a severe mounting space.
In order to solve this problem, many “constant power” charging methods have been proposed in which the power of the generator is effectively used to charge the battery. The prior art closest to the present invention is disclosed in Patent Document 1. is there. Below, the battery charge system shown in this patent document 1 is demonstrated.

FIG. 12 is a charge control circuit diagram of the prior art (Patent Document 1), and FIG.
Patent Document 1 discloses a battery charging method in a system in which DC power is supplied from an AC generator via a rectifier to a battery and another load connected in parallel to the battery. It is as follows.
1) Constant voltage charging: Calculation output of generator current command IG * by the first current target value calculation unit L1 In the first current target value calculation circuit L1, calculation is performed as a result of IG (= IB + IL) increasing as the load IL increases. The generator current command value IG * of the output becomes large and becomes a generator output corresponding to the increase in load. In this case, if a sudden load IL fluctuation occurs, a sudden load fluctuation occurs in the generator and the generator driving motor.

2) Constant current charging: Calculation output of the generator current command IG * by the second current target value calculation unit L2 When the load IL increases in the second current target value calculation circuit L2, the generator current command value IG * of the calculation output Becomes larger and the generator output corresponds to the increase in load. If a sudden load IL fluctuation occurs, a sudden load fluctuation occurs in the generator and the generator driving motor as in the above item 1).

3) Charging with constant generator output power: Calculation output of generator current command IG * by the third current target value calculation unit L3 In the third current target value calculation circuit L3, the denominator PG of the calculation formula is the generator power calculation. Since the output PG (= VB x IG) of the part L4 and the numerator is PG * x IG, the increase (change) in the denominator and the increase (change) in the numerator value are offset by the increase (change) in the load IL. The computation output IG * does not change. As a result, even if a load change occurs, the output of the set value PG * of the generator power setter S3 is maintained, so when the load IL increases, the generator current IG increases, but the battery charge power and The charging current decreases.
That is, since the charging current depends on the load fluctuation, a stable charging operation cannot be performed. In other words, this charging method controls the output power of the generator and cannot be said to charge the battery with constant power.

4) When charging the battery in a no-load (IL = 0) state, the generator output PG and the battery charging power PB (= VB × IB = VG × IB) are equal, and the operation is always PG = PB. Therefore, it is not possible to set arbitrary charging power within the generator output. That is, there is an operational problem that the battery charging power cannot be set by the generator output setting.
5) Further, in the battery floating operation (floating charging), the generator load fluctuates due to a change in the operation of the propulsion motor, so that a large load fluctuation is given to the generator driving motor.

JP-A-64-012826

From the above, in the electric propulsion system equipped with the battery, a high-performance lithium ion battery is adopted instead of the conventionally used lead battery, and the system configuration performs high current charging, which is a feature of the lithium ion battery. In this case, the generator output capacity increases correspondingly, and the problem arises that the generator and the power generator for driving the generator are increased in size and cost is increased.
In addition, the increase in size of the generator and the prime mover for driving the generator is an extremely important problem in an electric propulsion system such as an electric propulsion ship having a limited installation space. Furthermore, the biggest feature of the electric propulsion system is that any operation can be performed promptly, but on the other hand, rapid operation is accompanied by a sudden load change, and this sudden load change is added to the generator driving motor. In order to damage the prime mover, it is desirable to suppress sudden load fluctuations.

  Accordingly, an object of the present invention is to cope with the problems in the battery charging method described in Patent Document 1 above, and to use the charging method corresponding to the charging characteristics of the lithium ion battery to generate the generator output and the generator driving prime mover. Suppressing the capacity increase, suppressing the increase in size and cost of the generator and the power generator for driving the generator, reducing the fuel consumption by shortening the battery charging time, and obtaining the economic effect and environmental improvement effect, Further, when a sudden load change occurs, the generator output load of the electric system is prevented from changing rapidly to reduce damage to the generator driving motor.

In order to solve the above-described problems, according to the present invention, the generator control method is a hybrid-connected power source including a battery and a generator for charging the battery, and the battery is charged by the generator. In the electric propulsion system that operates by supplying power to the propulsion motor and the auxiliary equipment, a charging power control unit that adjusts the generator voltage so that the deviation between the actual charging power value and the charging power setting value becomes zero is provided. The charging power control unit is configured to perform a constant power charging method charging operation (invention of claim 1).
In the constant voltage charging method, charging power gradually decreases from the maximum value at the beginning of charging toward the end of charging, and in the constant current charging method, charging power gradually increases from the beginning of charging and reaches the maximum value at the end of charging. On the other hand, in the constant power charging method, since the charging power is constant from the beginning to the end of charging, the battery can be charged more effectively using the charging power. Further, since the generator capacity for charging the battery is determined by the maximum value of the charging power, the constant power charging method is superior to the constant voltage charging method and constant current charging method in terms of the required generator capacity.
In this regard, the invention of claim 1 includes a battery, and the battery, by including a charge power control unit that adjusts the generator voltage so that the deviation between the actual charge power value and the set charge power value becomes zero. A power supply with a hybrid connection consisting of a generator that charges the battery and performs charging operation of the constant power charging method in an electric propulsion system that supplies power to the propulsion motor and auxiliary equipment while charging the battery with the generator. As a result, it is possible to suppress the increase in the output of the generator and the capacity of the motor for driving the generator in the electric propulsion system, thereby suppressing the increase in size and cost of the generator and the motor for driving the generator. it can.
Further, in the first aspect of the invention, the battery charging time can be shortened by performing a constant power charging operation that can use the generator output more effectively, thereby reducing the operation time of the generator driving motor. Therefore, the fuel consumption of the prime mover can be reduced, and the economic effect and the environmental improvement effect can be obtained.
In addition, when applying the `` constant power charging '' method that effectively uses the generator output during initial charging that requires a large amount of charging power, the charging time can be shortened while suppressing an increase in generator capacity. In particular, a great effect can be obtained.
Next, a prime mover, such as a diesel engine, that drives the generator has constant output characteristics, so that the governor supplies fuel to the prime mover to keep the prime mover rotational speed constant when the generator load (electric power) changes. Since the amount is controlled, the output of the prime mover is controlled by making the fuel supply amount correspond to the load.
In this regard, in the generator control system according to the first aspect of the present invention, the battery power control unit adjusts the generator voltage so that the deviation between the actual charge power value and the charge power set value becomes zero. Since the charging operation can be executed with the control amount (feedback amount) as the “charging power”, the battery control is performed according to the “generator output power” and the “propulsion motor input power” in the control of the generator in the electric propulsion system. The control specifications can be controlled to be unified with “electric power”, and further, the control parameters can be unified with the prime mover governor control, so that the generator control circuit can be simplified.
On the other hand, in the conventional constant voltage charging method and constant current charging method, for example, a charging voltage control unit that adjusts the generator voltage so that the deviation between the charging voltage actual value and the charging voltage setting value becomes zero, the charging current actual value And a charging current control unit for adjusting the generator voltage so that the deviation between the charging current and the charging current set value becomes zero. In order to manage the battery charging power by such a charging voltage control unit and the charging current control unit, If the charging operation is performed, it is necessary to control the generator by following the battery current, the propulsion motor current, the battery voltage (= feeding line voltage), etc. that change every moment depending on the charging state of the battery, the driving state of the propulsion motor, etc. There is.
That is, in the charging operation by the charging voltage control unit, for example, a charging voltage setting value that becomes a predetermined charging power value is calculated based on the actual battery current value at that time, and each unit is controlled, and the charging current control unit For example, in the charging operation according to the above, each part is controlled by calculating a charging current set value that becomes a predetermined charging power value based on the actual value of the battery voltage at that time, and it is necessary to perform complicated calculation control in any case. .
On the other hand, in the generator control system according to the first aspect of the present invention, as the charging operation for managing the battery charging power, the “power”, which is the product of the voltage and current that change every moment, is controlled. Since the generator is controlled as a quantity), there is an advantage that the control can be simplified as described above, and cooperative control and control interlocking with the motor governor control are facilitated.

In the first aspect of the invention, as a configuration for obtaining the actual charge power value, a battery voltage detector for detecting the actual charge voltage value, a battery current detector for detecting the actual charge current value, It can be set as the structure provided with the charging power calculating part which outputs the product of a charging voltage actual value and the said charging current actual value as said charging power actual value (invention of Claim 2).
In the second aspect of the invention, a charging voltage control unit that adjusts a generator voltage so that a deviation between the charging voltage actual value and the charging voltage setting value becomes zero; the charging current actual value and the charging current; A charging current control unit that adjusts a generator voltage so that a deviation from a set value becomes zero; a constant voltage charging method by the charging voltage control unit; a constant current charging method by the charging current control unit; The charging power control unit can be configured to selectively execute charging operations of three types of charging methods, ie, a constant power charging method (invention of claim 3).
In the invention according to any one of claims 1 to 3, a multi-stage constant power charging method in which charging from the initial charging time to the final charging time is gradually reduced as the charging progresses. The charging time can be shortened by charging at the same time, and an increase in generator capacity can be suppressed (invention of claim 4).
In the invention of claim 3 or 4, two priority modes, a battery priority mode and a motor priority mode, are provided as selectable modes in the constant power charging method, and the battery charging power is increased in the battery priority mode. When the propulsion motor power increases in the motor priority mode, the power obtained by lowering the propulsion motor rotation speed within the generator output limit is applied to the battery charging power. The power obtained by reducing the battery charging power by adjusting the power setting value can be applied to the propulsion motor power (invention of claim 5).
According to the fifth aspect of the present invention, as control for reducing the charging power when the propulsion motor power increases in the motor priority mode, the generator is set so that the deviation between the actual charging power value and the set charging power value becomes zero. Since the charging power control unit that adjusts the voltage can perform the charging operation based on the charging power actual value itself as the control amount (feedback amount) based on the charging power setting value reduced by the amount corresponding to the propulsion motor power, Highly stable control can be realized with the control circuit.
In the invention of claim 5, a cut-off mode for canceling the two priority modes is provided, and in this cut-off mode, the battery can be charged by any one of the constant voltage, constant current and constant power charging methods. (Invention of claim 6).

In the invention according to any one of the first to sixth aspects, the generator is driven for driving the generator against a load fluctuation that occurs in response to an operation of stopping or operating the propulsion motor. The rotation speed change time of the propulsion motor can be set so that the control of the prime mover governor device that keeps the rotation speed of the prime mover constant can be followed (invention of claim 7).
In the invention according to any one of claims 1 to 7, when a rapid stop operation of the propulsion motor is performed, the reduced power of the propulsion motor generated by the rapid stop is temporarily applied to the battery charge power as a simulated power. Then, by performing the charging operation by the charging power control unit based on the charging power setting value to which the simulated power is applied, the rapid load fluctuation given to the generator driving prime mover is suppressed, and the prime mover governor device is controlled. It can be set as the structure which can be followed (invention of Claim 8).
In the invention of claim 8, as the control for applying the reduced power of the propulsion motor to the battery charge power as a simulated power during the rapid stop operation of the propulsion motor, the deviation between the actual charge power value and the charge power set value is zero. The charging power control unit that adjusts the generator voltage at the same time allows the charging operation to be performed with the actual charging power value itself as the control amount (feedback amount) based on the charging power setting value to which the simulated power is applied. Highly stable control can be realized with a circuit.
In the invention of claim 8, when the battery voltage exceeds a predetermined value when performing the charging operation by the charging power control unit based on the charging power setting value to which the simulated power is applied, the generator output The charging power set value can be lowered so that the voltage does not exceed the limit voltage value (invention of claim 9).
Moreover, in the invention of any one of claims 7 to 9, in stopping the generator driving prime mover, the generator load is detected by detecting that the generator load has become unloaded, It can be set as the structure which avoids the rapid load reduction of the motor | power_generator for a generator drive (invention of Claim 10).

  According to the present invention, in an electric propulsion system that operates by supplying power to a propulsion motor and an auxiliary machine while charging a battery with a generator such as an engine-driven generator, an actual charge power value and a set charge power value A charging power control unit that adjusts the generator voltage so that the deviation becomes zero is provided, and the constant power charging method by the charging power control unit can be executed, thereby making it possible to perform the constant voltage charging method, Using a constant power charging method that can use the generator output more effectively than the current charging method, suppressing the increase in capacity of the generator output and the motor for driving the generator, the large size of the generator and the motor for driving the generator Power consumption and cost increases, and shortening the battery charging time, shortening the operating time of the generator drive motor, reducing the fuel consumption of the motor, and obtaining economic and environmental improvement effects. It is possible. In addition, as a charging method in the electric propulsion system, a “constant power charging” mode by the charging power control unit is added to the conventional “constant voltage charging” and “constant current charging” modes, and these three modes ( The charging operation can be selectively executed in the charging method. In addition, the “constant power charging” method that makes effective use of the generator output is particularly suitable during initial charging that requires a large amount of charging power, and the generator capacity can be reduced by using the “constant power charging” method during initial charging. It is possible to significantly reduce the charging time while effectively suppressing the increase.

  Also, according to the present invention, it is possible to select either “battery priority” or “motor priority” mode while performing “constant power charging”, and when battery charging power is insufficient in “battery priority” mode. Applying the electric power obtained by reducing the rotation speed of the propulsion motor to the battery charge power, and when the propulsion motor power increases in the “motor priority” mode, the electric power obtained by reducing the charge power is used as the propulsion motor power. The operation to allocate to is performed. According to the present invention, as control for reducing the charging power when the propulsion motor power increases in the “motor priority” mode, the generator is set so that the deviation between the actual charging power value and the charging power setting value becomes zero. The charging power control unit that adjusts the voltage performs the charging operation based on the charging power actual value itself as the control amount (feedback amount) based on the charging power setting value reduced by the amount appropriated to the propulsion motor power. Highly stable control can be realized.

Furthermore, in the present invention, when a sudden reduction of the propulsion motor load occurs due to the rapid stop operation of the propulsion motor, the reduced power of the propulsion motor generated by the rapid stop is temporarily applied to the battery charging power as simulated power, By performing the charging operation by the charging power control unit based on the setting value of the charging power to which the simulated power is applied, the load state of the generator is reduced to a load state that gently decreases, and a sudden load fluctuation applied to the generator driving motor is reduced. The control of the prime mover governor device is made to follow, and the increase in the rotational speed of the prime mover is prevented. According to the present invention, as the control for applying the reduced power of the propulsion motor to the battery charge power as simulated power during the rapid stop operation of the propulsion motor, the deviation between the actual charge power value and the charge power set value is zero. The charging power control unit that adjusts the generator voltage at the same time makes the charging operation based on the charging power actual value itself as the control amount (feedback amount) based on the charging power setting value to which the simulated power is applied. Highly controllable.
Also, when stopping the generator drive motor for any reason, give priority to the stop operation of the generator drive motor, and stop the generator after the generator is in a no-load state. The engine can be stopped without shock.

Basic circuit for charge control according to the present invention Comparison explanatory diagram of charging operation by each charging method of FIG. Example of charging operation using multi-stage constant power charging Basic circuit diagram of electric propulsion system control Generator output limit control characteristics Propulsion motor load characteristics FIG. 4 is a first detailed explanatory diagram of the control circuit of FIG. FIG. 4 is a second detailed explanatory diagram of the control circuit of FIG. Battery priority mode operation pattern diagram (charging power increased from 02 points to 22 points) Operation pattern of motor priority mode (Motor speed increased from 03 to 23) Operation pattern of motor priority mode (motor: rapid stop) Operation pattern of motor priority mode (battery: floating operation) System control application basic circuit diagram Motor stop operation pattern diagram Prior art charge control circuit diagram Explanatory diagram of charging operation in FIG.

FIG. 1 is a basic circuit of charge control according to the present invention, and FIG. 2 is a comparative explanatory view of charging operations by each charging method.
(Charging operation for each charging method)
1) Constant Voltage Charging Method In FIG. 1, “constant voltage charging” is a method of charging a battery with a battery terminal voltage (charging voltage actual value) VBi as a constant voltage. As shown in FIG. 2A, the charging characteristic is charged at a constant voltage from the charging start point a to the point b, so that the charging current decreases from IBa to IBb as the battery internal electromotive voltage eB increases. The charging power in this charging method is large at the point a, and decreases to the power PBb at the point b.

2) Constant Current Charging Method In FIG. 1, “constant current charging” is a method of charging a battery with a charging current (charging current actual value) + IBi (indicating charging with +) as a constant current. As shown in FIG. 2 (b), the charge characteristic is charged at a constant charge current from the point-a-point current IBa to the point-b current IBb at the start of charging. Therefore, the battery terminal voltage VBa The voltage rises to the point b voltage VBb. The charging power in this charging method is such that the power PBa at point a is small and the power PBb at point b is large.

3) Constant Power Charging Method In FIG. 1, “constant power charging” is a method of charging a battery with a constant charging power (actual charging power value) PBi, which is the product of the charging current IBi and the battery voltage VBi. As shown in FIG. 2C, the charging characteristic is constant charging power from point a to point b. The battery voltage VBi increases from the point a voltage VBa to the point b voltage VBb as the charging progresses, and the charging current decreases from the point a current IBa to the point b current IBb.

As can be seen from the above charging methods, in the case of “constant voltage charging”, the charging power gradually decreases from the maximum value at the initial stage of charging to the end of charging, and in the case of “constant current charging”, the charging power is reduced. While it is a characteristic that gradually increases from the beginning of charging and reaches the maximum value at the end of charging, in the case of `` constant power charging '', the charging power is constant from the beginning to the end of charging, so the charging power is used more effectively. To charge the battery. In addition, since the capacity of the generator that charges the battery is determined by the maximum value of the charging power, the "constant power charging" method is superior to the "constant voltage" and "constant current" methods in terms of the required generator capacity. .
In this way, if the “constant power charging” method is used to charge the battery with a constant power from the beginning of charging to the end of charging, the battery can be charged using the generator power more effectively, and the battery charging time can be shortened. .

(Multistage constant power charging)
FIG. 3 shows an example of charging operation by multi-stage constant power charging.
During the period from point a: t0 to point b: t1, charging is performed with the first stage constant power by the constant charging power PBi1. Charging is started from the battery voltage VBia at the point a and the charging current IBia, the battery voltage increases with the passage of time, and the charging current decreases. When the battery voltage reaches VBib1 or the charging current reaches IBib1, switching to the second-stage constant power charging PBi2 in which the charging power is reduced to PBi2.

When the second-stage constant power charging is switched to PBi2, the battery voltage decreases to VBib2 and the charging current temporarily decreases to IBib2, but the battery voltage increases and the battery current decreases with time. When the battery voltage reaches VBic1 or the charging current reaches IBic1, the charging power is switched to the third-stage constant power charging PBi3 in which the charging power is reduced to PBi3.
When the third stage constant power charging is switched to PBi3, the battery voltage temporarily decreases to VBic2 and the charging current decreases to IBic2, but the battery voltage increases and the battery current decreases with time. When the battery voltage reaches VBid1 or the charging current reaches IBid1, the charging power is switched to the fourth-stage constant power charging PBi4 in which the charging power is reduced to PBi4.

When the fourth stage constant power charging is switched to PBi4, the battery voltage temporarily decreases to VBid2 and the charging current decreases to IBid2, but the battery voltage increases and the battery current decreases with time. Then, when the battery voltage reaches VBie1 or the charging current reaches IBie2, it is determined that the battery has reached substantially full charging, for example, switching to constant voltage charging, and charging is terminated at the point f when the charging current reaches IBif. Here, for example, in the case of a lithium ion battery, it is generally determined that a fully charged state is reached when the battery terminal voltage reaches 4.1 V. It is determined that the battery is in a state just before “full charge”. For example, when the battery terminal voltage reaches approximately 4.0 V, it is determined that the battery is almost fully charged.
Note that the determination values of the battery voltage and the charging current at the point d or the point e may be set, and when the set values are reached, it may be determined that the battery has been fully charged and the charging is terminated.

(Basic circuit for electric propulsion system control)
An example of the basic circuit of the electric propulsion system control for executing the above charging method is shown in FIG.
The AC power of the AC generator 5 (G) is converted into DC power by the rectifier 8 (Di), supplied to the battery 1 (B) as charging power, and propelled through the power converter 14 (INV). The electric motor 12 (M) is supplied as propulsion electric motor power, and further supplied to the auxiliary machine 33 as auxiliary electric machine power.
Further, the generator driven by the prime mover 4 (DE) has the constant output limiting characteristic shown in FIG. 5A, and is limited so that the generator output does not exceed the limit value even when the load increases. In addition to being controlled, the generator voltage is controlled following the battery voltage that changes in the battery charging operation.
For example, a propulsion motor 12 (M) that drives a propeller (propulsion unit) for propulsion of an electric propulsion vessel is provided with a speed detector 13 (TD) that detects the rotational speed of the propulsion motor 12 (M). ing. Then, the motor control unit 32-M controls the power converter 14 (INV) using the speed detection signal Ni of the speed detector 13 (TD) of the propulsion motor 12 (M) as a feedback signal, and the propulsion motor 12 (M) Has a function of stably controlling the rotation speed to a desired set speed.

In FIG. 4, the electric propulsion system is controlled as follows.
1. Constant voltage charging In this case, “constant voltage” is selected with the charge changeover switch 19 (COSB), and the battery charging voltage setting value VBs (hereinafter also referred to as “charging voltage setting value VBs”) set with the setting device 21 (VRVB). ), The generator is controlled using the battery charge voltage actual value VBi detected by the battery voltage detector 2 (VDB) (hereinafter also referred to as “charge voltage actual value VBi”) as a feedback amount, and FIG. Constant voltage charging control as shown in FIG.
2. Constant current charging In this case, select “Constant current” with the charge switch 19 (COSB) and set the battery charging current setting value IBs (hereinafter referred to as “charging current setting value value IBs”) set with the setting device 22 (VRIB). 2), the battery charging current actual value IBi detected by the battery current detector 3 (SHB) (hereinafter also referred to as “charging current actual value IBi”) is used as a feedback amount to control the generator, and FIG. The constant current charging control as shown in FIG.

3. Constant power charging In this case, select “Constant power” with the charge selector switch 19 (COSB) and set the battery charging power setting value PBs set in setting 23 (VRPB) (hereinafter also referred to as “charging power setting value PBs”). On the other hand, the generator is controlled using the battery charge power actual value PBi (= VBi × IBi) (hereinafter also referred to as “charge power actual value PBi”) calculated by the calculation unit 32-2 as a feedback amount, and FIG. Constant power charging control as shown in (c) is performed.
The generator output PGi is obtained by calculating PGi = generator voltage VGi × generator current IGi in the calculation unit 32-1. Further, the generator output current limit value IGL = PGs ÷ VGi is calculated from the generator output upper limit setting value PGs and the generator voltage VGI, and the generator output current is calculated by the calculated limit value IGL. IGi is limited.

The load characteristics of the propulsion motor that drives the propeller are shown in FIG. 6 and change in proportion to the cube of the rotational speed (PMi∝N ³ ). The propulsion motor input power PMi according to the driving state of the propulsion motor is obtained from the propulsion motor power receiving end voltage VMi and the input current IMi by calculation of PMi = VMi × IMi in Equation 3-3 in the calculation unit 32-3.
In addition, the auxiliary machine power PAX is obtained by calculating PAXi = VAXi × IAXi in the equation 4) in the calculation unit 32-4 and becomes a substantially constant load on the generator.

The electric propulsion system control device 32 is mainly composed of an electric power calculation unit 32-C, a generator control unit 32-G, an electric motor control unit 32-M, etc., and detection from a voltage detector and a current detector arranged in each unit. The following actual power calculation and condition calculation are performed in each part by the signal.
1) 32-1 ： Generator actual output calculation PGi ＝ VGi × IGi
2) 32-2: Battery actual charge power calculation PBi = VBi x IBi
3) 32-3: Propulsion motor actual input power calculation PMi = VMi x IMi
4) 32-4: Auxiliary machine power calculation PAXi = VAXi x IAXi
5) 32-5: Generator current limit value calculation IGL = PGs ÷ VGi
6) 32-6: Difference calculation between generator output upper limit set value and actual output ΔPG = PGs-PGi
7) 32-7: Charge power command value calculation that can be supplied to the battery PBsi = PGs-PMi-PAXi
8) 32-8-1: Input power calculation that can drive the propulsion motor PMsi = PGs-PBs-PAXi
9) 32-8-2: Rotational speed command value calculation that can drive the propulsion motor Nsi = K × 3√ (PMsi)
109) 32-9: Detecting the rotational speed of the propulsion motor
ΔNi = Ni−Ns> α or ΔNi = Ns−Ni> β
(Ns: Rotation speed setting value)

In particular, in the “constant power” charging, the priority changeover switch 20 (COSM) can select each mode of “off”, “battery” priority, and “motor” priority.
Regarding the control method of the “battery” priority mode and the “motor” priority mode, for example, there is a method disclosed in Reference Document 1 (Japanese Patent Laid-Open No. 2009-262671). The technology described in this reference 1 can select two methods, “constant voltage charging” and “constant current charging” as charging methods, and can be operated by switching between “battery” priority mode and “motor” priority mode. It is a thing. In the technique described in Reference Document 1, particularly as control for reducing the charging power when the propulsion motor power is increased in the “motor” priority mode, the electric power to be applied to the increase in the propulsion motor power is decreased. In the “constant voltage charging”, the charging power command value VBSC (= PBd ÷ IBi) is obtained by dividing the charging power value PBd by the battery current actual value IBi at that time, and “constant current charging”. In “charging”, the charging power command value IBSC (= PBd ÷ VBi) is obtained by dividing the charging power value PBd by the battery voltage actual value VBi at that time, and the battery is charged with the obtained command value.

With respect to the technique of the above-mentioned Reference Document 1, in the present invention, as a selectable charging method, in addition to “constant voltage charging” and “constant current charging”, the deviation between the actual charging power value and the charging power set value is zero. "Constant power" charging is newly provided by the charging power control unit to adjust the generator voltage so that "battery" or "motor" can be prioritized during "constant power" charging operation Yes. And this invention is a control for reducing the charging power especially when the propulsion motor power is increased in the “motor” priority mode, and the charging power value PBSi reduced by the power amount to be applied to the increase amount of the propulsion motor power. The charging operation is performed by adjusting the generator voltage so that the deviation between the charging power actual value and the charging power setting value based on the charging power value PBSi becomes zero. Is a control amount (feedback amount), which is different from the technique of Reference 1.
Further, according to the present invention, when the propulsion motor that is the maximum load of the electric propulsion system is urgently stopped during the “constant power” charging operation, or when the propulsion motor is urgently stopped during the battery floating operation, Propulsion motor power generated by an emergency stop so that the rotational speed does not increase due to a follow-up delay in the drive control of the generator driving motor that responds to fluctuations in the generator load due to a drastic decrease in the load power generated in time The simulated power due to the decrease in the power is temporarily converted into battery charging power to level the load fluctuation so that the drive control of the generator driving motor can follow. As a result, even if sudden load fluctuations occur, the generator load is leveled, and the generator driving motor load is also leveled, so the generator driving motor drives the generator at a constant rotational speed by drive control. can do.
The control operation will be described in detail below with reference to FIGS. 7 and 8 which are detailed explanatory diagrams of the control circuit of FIG. 4 together with FIG. 7 and 8 show detailed circuits of different portions in the control circuit of FIG. 4, respectively.

3-1. Off mode This mode cancels the priority mode and enables any one of the constant voltage, constant current, and constant power charging methods. For example, the “multi-stage constant power charging” method as shown in FIG. It is also good.
Here, a configuration example of a basic control operation for the generator in each charging method of constant voltage, constant current, and constant power will be described with reference to FIG. 8, but the control operation for the generator in the present invention is an example of this configuration. It is not limited to.

(Control operation for the generator in the constant voltage charging method)
When “constant voltage” is selected by the charge switch 19 (COSB), the charging voltage actual value VBi detected by the battery voltage detector 2 (VDB) and the battery voltage setting device 21 (VRVB) are set. The charging voltage adjuster AVRB outputs an adjustment signal so that the deviation at the abutting point a with the charging voltage setting value VBs becomes zero, and the generator voltage setting value VGs to be given to the generator voltage control loop is determined by this adjustment signal. The voltage level is adjusted.
Further, in the generator voltage control loop, the generator voltage adjustment is performed so that the deviation at the butt point f between the generator voltage actual value VGI detected by the generator voltage detector VDG and the generator voltage set value VGs becomes zero. The generator AVRG outputs an adjustment signal, and the current level of the generator current set value IGs given to the generator current control loop is adjusted by the adjustment signal.
Furthermore, in the generator current control loop, the generator current adjustment is performed so that the deviation at the butt point g between the generator current actual value IGI detected by the generator current detector SHG and the generator current set value IGs becomes zero. The generator ACRG outputs an adjustment signal, which adjusts the generator field current IGf via the generator excitation device 6 (EX), controls the generator voltage VGI, and controls the generator current IGi. Is done.

(Control action for generator in constant current charging method)
When “constant current” is selected with the charge switch 19 (COSB), it is set with the actual charge current IBI detected by the battery current detector 3 (SHB) and the battery current setter 22 (VRIB). The charging current regulator ACRB outputs an adjustment signal so that the deviation at the matching point b with the charging current setting value IBs becomes zero, and by this adjustment signal, the generator voltage setting value VGs to be given to the generator voltage control loop is output. The voltage level is adjusted, and the generator is controlled in the same manner as described in the constant voltage charging method.

(Control action for generator in constant power charging method)
When “constant power” is selected by the charge switch 19 (COSB), the charging power actual value PBi (= VBi × IBi) calculated by the calculation unit 32-2 and the signal time setting unit 32-15 are used. The charging power adjuster APRB outputs an adjustment signal so that the deviation at the matching point e with the charging power setting value PBsiB given in this way becomes zero, and the generator voltage setting given to the generator voltage control loop by this adjustment signal The voltage level of the value VGs is adjusted, and the generator is controlled in the same manner as described in the constant voltage charging method.

3-2. Battery Priority Mode This “battery priority” mode is an operation mode that prioritizes the supply of battery charging power within the generator output capacity when the system load increases, and its operation pattern is shown in FIG. 9A.
When the charging power set value PBs is increased by the battery power setting unit 23 (VRPB) (see also FIGS. 4 and 8) of FIG. 7, the charging power PBi increases from t0 = 02 point of FIG. 9A to t1 = 12 point. The generator output PGi reaches t1 point = 11 from t0 point = 01.

The generator actual output PGi = PBsi + PMi + PAXi at the point t1 = 11 coincides with the upper limit value PGs set by the generator output upper limit setter 26 (VRPG).
At this time, the calculation unit 32-6 (see also FIGS. 4 and 8) in FIG. 7 calculates the equation ΔPG = PGs−PGi = 0, and the calculation unit 32-5 (see FIGS. 4 and 8) 5) Since the generator output current IGI is limited by the calculation of the expression IGL = PGs ÷ VGi, the generator output cannot be increased after the t1 point.
In addition, the generator output indicator lamp 29 (PGL: see FIG. 4) is turned on to notify that the limit operation has been reached when the generator output reaches the upper limit at the point t1, and ΔPG of the calculation unit 32-6 The calculation of the calculation unit 32-8 in FIG. 7 (see also FIGS. 4 and 8) is started under the condition of = 0. Further, depending on the condition that ΔPG = 0, the signal switching unit (speed setting signal switching unit) 32-17 in FIG. 7 is changed from a signal having the rotation speed setting value Ns as a command value to a signal having the calculation value Nsi as a command value. Switch.

  When the battery charge power set value PBs is further increased from t1: 12 points, the calculation unit 32-8 in FIG. 7 (see also FIG. 4 and FIG. 8) shows 8) by calculating PMsi = PGs−PBs−PAXi The electric power PMsi that can be supplied to the propulsion motor is calculated, and the propulsion motor rotation speed Nsi = K × 3√PMsi obtained from the calculated PMsi is input as a rotation speed command from the h point in FIG. Then, feedback control is performed by the rotation speed detection signal Ni.

That is, when the battery charge power set value PBs is further increased from t1: 12 points, the propulsion motor power PMi is decreased from t1 point = 13 points to t2 = 23 points (PMi = 0), and the resulting power Is used for battery charging power.
When t2 is reached, the propulsion motor rotational speed = 0 = 23 points, the auxiliary machine electric power 24 points, and the generator output are the upper limit 21 points, so the battery charging power can no longer be increased from the electric power value of 22 points. At this time, the battery charging current limit indicator lamp 30 (PLBL: see FIG. 4) is turned on to notify that the charging current has reached the upper limit.

Naturally, the generator output current is limited by the expression IGL = PGs ÷ VGi of the arithmetic unit 32-5 (see FIGS. 4 and 8), so the battery power setting unit 23 (VRPB) in FIG. , See FIG. 8), the charging power cannot be increased. The generator in the period from t2 to t3 is operated to supply power to the battery and the auxiliary machine by the generator upper limit output.
If the charging power is reduced from the point t3, the electric power supply to the propulsion motor becomes possible, and the propulsion motor resumes operation. Further, if the load becomes a load state after the point t4, the original charging, the original propulsion motor Return to driving.

3-3. Motor priority mode The “motor priority” mode is an operation mode that prioritizes the supply of propulsion motor power when the system load increases. FIG. 9B shows an operation pattern thereof.
When the set value Ns of the rotation speed setting device 28 (VRNM) (see also FIGS. 4 and 7) of the propulsion motor in FIG. 8 is increased, the propulsion starts from the point t0: 03 of the operation pattern of the motor priority mode shown in FIG. 9B. The motor power PMi increases and reaches t1: 13 points.

  t1: 11 points are points where the generator actual output PGi = PBsi + PMi + PAXi coincides with the upper limit PGs set by the generator output upper limit setter 26 (VRPG) of FIG. 8 (see also FIGS. 4 and 7). The equation ΔPG = PGs−PGi of the calculation unit 32-6 in FIG. 8 (see also FIGS. 4 and 7) becomes ΔPG = 0, and the propulsion motor rotation speed cannot be further increased. Therefore, control is performed so that the electric power obtained by reducing the battery charging power PBi is applied to the increasing propulsion motor power.

  If the condition ΔPG = PGs−PGi = 0 is satisfied in the equation 6 of the calculation unit 32-6 (see also FIGS. 4 and 7) of FIG. 8, the calculation unit 32-7 (FIGS. 4 and 7) of FIG. Also starts operation. The computing unit 32-7 calculates the charging power PBsi that can be supplied to the battery by computing 7) the expression PBsi = PGs-PMi-PAXi. Further, the signal switching unit 32-14 (see also FIG. 7) in FIG. 8 is switched from the PBs signal to the PBsi signal according to the condition of ΔPG = 0. The signal PBsi becomes the signal PBsiA through the point d in FIG. 8, and is passed through the signal time setting unit 32-15 (see also FIG. 7) in FIG. 8 to obtain the signal PBsiB. Further, this signal is inputted to the matching point e in FIG. 8 and matched with the actual charging power value (charging power actual value) PBi signal calculated by the calculation unit 32-2 in FIG. 8 (see also FIGS. 4 and 7). Thus, feedback control is performed. Further, when the generator output reaches the upper limit output at t1: 11, the indicator lamp 29 (PLGL: see FIG. 4) is turned on to notify that the generator output has reached the limit.

When the propulsion motor rotation speed is further increased from t1, the propulsion motor power PMi goes from t1: 13 points to t2: 23 points shown in FIG. 9B. At this time, the reduced charging power is supplied to the propulsion motor by the charging power PBsi calculated by the expression PBsi = PGs−PMi−PAXi of the calculation unit 32-7 (see also FIGS. 4 and 7) of FIG. Appropriated. When t2 reaches 23 points, the battery charging power PBsi = 0, so that it is no longer possible to obtain propulsion motor power that can be applied.
Further, since the generator output is limited by the generator output current IGL according to 5) expression IGL = PGs ÷ VGi of the calculation unit 32-5 (see also FIG. 4) in FIG. 8, the rotational speed of the propulsion motor is increased. Can not. At this time, the motor rotation speed limit indicator lamp 31 (PML: see FIG. 4) is turned on to notify that the rotation speed has reached the upper limit.

Further, a signal indicating that PBsi = 0 in the calculation of the calculation unit 32-7 (see also FIGS. 4 and 7) in FIG. 8 is given to the rotation speed limiting unit 32-16 (see also FIG. 7) in FIG. Since the rotation speed setting signal Ns is limited by setting the rotation speed when PBsi = 0 to the upper limit value NML, the motor rotation speed setting device 28 (VRNM) of FIG. 8 after t2 (see also FIGS. 4 and 7) Even if the operation is performed to increase the rotation speed, the rotation speed cannot be increased.
Since the generator upper limit output state is in the period from t2 to t3, electric power is supplied to the propulsion motor and the auxiliary machine, and the battery charging power is operated at zero.

If the rotation speed of the propulsion motor is decreased from t3, the reduced propulsion motor power is supplied to the battery as charging power, and the battery charging operation is resumed. After t4, at the predetermined charge and at the predetermined propulsion motor rotation speed. Return to the original operating state.
As described above, the priority changeover switch 20 (COSM) in FIG. 4 (see also FIGS. 7 and 8) is switched to the “battery” priority or “motor” priority mode, and the power within the set upper limit of the generator output. This makes it possible to perform an operation suitable for the purpose.

Although the above operations are operations in normal operation, it is assumed that the propulsion motor is suddenly accelerated or rapidly stopped to avoid an emergency situation.
Here, the generator used in the electric propulsion system is driven by a prime mover, and the prime mover is driven and controlled to operate at a constant rotational speed with respect to load fluctuations. However, when a rapid load change occurs, there arises a problem that the prime mover drive control cannot follow.

On the other hand, since the maximum load in the electric propulsion system is a propulsion motor, when the propulsion motor is suddenly accelerated or suddenly stopped, the generator load and the prime mover load change rapidly. In the case of the former rapid acceleration operation, the generator load and the prime mover load increase rapidly. Therefore, when the drive control cannot follow, the prime mover stops (common name: engine stall), which impedes operation. In the case of the latter rapid stop operation, the generator load and the prime mover load are rapidly reduced. Therefore, when the drive control cannot follow, the rotational speed of the prime mover increases rapidly.
This phenomenon is the same phenomenon as an automobile engine in which the engine speed increases rapidly when the gearbox is set to neutral with the accelerator depressed, and it also causes damage to the prime mover. Should be avoided as much as possible.

4). When the load fluctuates, the load response characteristics of the prime mover are: difference in fuel used (for example, gasoline (gasoline engine) and light oil (diesel engine)), presence or absence of spark plug (gasoline engine (present), diesel engine (none)) Responsiveness (small prime movers have a fast response, large prime movers have a slow response), and so on, depending on the type and output of the prime mover used. A diesel engine is often used as a prime mover of the electric propulsion system, and as described above, the prime mover rotational speed is controlled by a governor device (drive device) so as to be a constant rotational speed.

If it is assumed that the load response time of the prime mover governor control is about 0 to 100 to 0% / 5 to 10 seconds, the propulsion motor rotational speed command is raised or lowered by the signal time setting unit 32-18 in FIG. If the change time is set to be about 5 to 10 seconds, the prime mover governor control can follow and prevent the prime mover from stopping (commonly known as the engine stall) or the increase in rotational speed.
The following describes how to improve sudden load changes.

4-1. In the case of the propulsion motor rapid acceleration operation In the case of the propulsion motor rapid acceleration operation, the switch 32-19 (SWN) shown in FIG. 7 is turned ON, and the change time of the speed signal time setting unit 32-18 in FIG. The command is changed to a command rise time (for example, 5 seconds) that can be followed by control.
When the propulsion motor rotation speed and the propulsion motor power PMi are rapidly changed from t0: 03 point to t2: 23 point (for example, in 5 seconds) in FIG. 9C (motor priority mode operation pattern), the generator output is t1 (propulsion motor). The limit value: 11 points is reached when the power PMi is 13 points. Further, if the prime mover drive can follow the fluctuation of the propulsion motor load due to the change in rotational speed command from t0: 03 point to t2: 23 point, the prime mover rotational speed is kept constant and the prime mover stop (engine stall) does not occur.
Since the generator is in the output limiting operation state during the period from t1: 11 points to t2: 21 points, load fluctuations of the generator and the prime mover do not occur.

4-2. In the case of the propulsion motor rapid stop operation The control conditions for reducing the problem of the rapid increase in the motor rotation speed when the propulsion motor is rapidly stopped are listed below.
A) “Constant power” is selected by the charge changeover switch 19 (COSB) shown in FIG. 7 (see also FIGS. 4 and 8).
A) The “motor” priority mode is selected with the priority changeover switch 20 (COSM) shown in FIG. 7 (see also FIGS. 4 and 8).
C) The change time of the propulsion motor speed signal time setting unit 32-18 shown in FIG. 7 is set to a time setting that matches the prime mover governor response time. For example, if the prime mover response time is 5 seconds, the change time is set to about 5 to 10 seconds with a margin.
D) When sudden deceleration or sudden stop operation is performed, the switch 32-19 (SWN) shown in FIG. 7 is turned on, and the speed signal time setting unit 32-18 shown in FIG. Further, the load decrease fluctuation of the electric motor is temporarily converted (applied) to the battery charging power, and the load fluctuation of the prime mover is alleviated.

E) In the floating operation, as in the above item d), the load decrease fluctuation of the motor is temporarily converted (applied) to the battery charging power, and the load fluctuation of the prime mover is alleviated.
F) When stopping the prime mover, the generator is stopped following the prime mover stop operation.
In short, when the load of the propulsion motor in the electric propulsion system suddenly decreases, the sudden decrease in the load is temporarily converted into battery charging power and the load fluctuation of the prime mover is eased so that the prime mover governor control can follow. To prevent the rotation speed of the machine from increasing.

This will be specifically described below.
When rapidly stopping the propulsion motor, the switch 32-19 (SWN) shown in FIG. 7 is turned ON, and the change time of the speed signal time setting unit 32-18 shown in FIG. 7 is changed from, for example, 5 seconds to about 0 seconds. . Here, considering the emergency stop operation, it is also considered to set the speed command to stop in about 0 seconds (that is, speed 0).
If the propulsion motor speed command is rapidly stopped at t3: 33 to t4: 43 in FIG. 9C at a speed of about 0 seconds, the rotation speed of the propulsion motor is changed from t3: 33 to t4: 43 with regenerative braking. Decelerate to the point and stop.

At this time, since the propulsion electric motor power PMi decreases from the power value of 33 points to 0 of 43 points in a short time, the generator load and the motor load also rapidly decrease from 31 points to 41 points. Here, when the battery charging power PBs = PBi is large, the battery charging power returns to the power value of 32 points from 0 to 42 points, and the generator load and the motor load are about 41 points from the power value of 31 points. It shifts to the power value and the load fluctuation range is small.
However, when battery charge power PBs = PBi is small, the amount of change at 31 to 41 points is large, so if the machine propulsion motor is rapidly stopped in this operating state, the load fluctuation range at 31 to 41 points becomes large. Therefore, a large load fluctuation is given to the generator and the prime mover.
A control method for reducing this large load fluctuation will be described below.

The rotational speed state detector 32-9 (see also FIG. 4) shown in FIGS. 7 and 8 calculates a rotational speed difference ΔNi = Ni−Ns between the rotational speed set value Ns and the actual rotational speed Ni, and the rotational speed difference is calculated. Comparison processing with the discrimination reference value α is performed. Here, the rotation speed difference determination reference value α is selected from α = 5% to 10% rotation speed, for example.
When the deceleration time of the rotational speed set value Ns of the propulsion motor is short and the deceleration time of the actual rotational speed Ni is long, a difference occurs between Ns and Ni, and when ΔNi = Ni−Ns> α, the rotational speed difference ΔNi Is detected, and it is determined that the rotation speed difference has been generated.

At this time, the rotational speed Ni of the propulsion motor follows the speed set value Ns, and is stopped by the regenerative braking operation of the power converter.
When the set time of the speed signal time setting unit 32-18 shown in FIG. 7 is long, the actual rotation speed Ni of the propulsion motor decreases following the rotation bottom degree command value Ns, so the rotation speed difference ΔNi is not detected. Only when the rapid stop operation is performed, the rotational speed difference ΔNi is detected.

  When the detector 32-9 shown in FIG. 7 (see also FIGS. 4 and 8) detects the rotational speed difference ΔNi, the switch 32-10 in FIG. 7 (see also FIG. 8) is detected by the signal of the detector 32-9. Is operated to operate the simulated power generation unit 32-11 (see also FIG. 8) in FIG. 7 and the battery charge power discrimination unit (discrimination unit) 32-12 (see also FIG. 8) in FIG. The simulated power command PMCi from the simulated power generation unit 32-11 is the actual power PMi calculated by the calculation unit 32-3 in FIG. 7 (see also FIGS. 4 and 8) at the time when the signal is received from the switch 32-10. Is generated as a signal that attenuates to 0 at t5: 53 over a period of time that can be followed by the prime mover governor control, and is given to the determination unit (battery charge power determination unit) 32-12.

Further, the simulated charging power command PBCs of the simulated power generating unit 32-11 (see also FIG. 8) in FIG. 7 is increased from t3: 32 point 0 in FIG. 9C to t5: 52 point battery charging power PBs = PBi. A signal is generated and applied to the determination unit 32-12 (see also FIG. 8) in FIG. The discriminating unit 32-12 compares the charging power installation value PBs with the actual charging power PBi calculated by the calculating unit 32-2, and passes the signal PMCi and the signal PBCs until PBs = PBi. Is given to the matching point c in FIG. 8 (see also FIG. 7), and the signal PMCi is given to the matching point d in FIG.
The operation at this time will be described in more detail with reference to FIG. 9C.

t3: When the propulsion motor is rapidly stopped at 33 points (when the change time set by the speed signal time setting unit 32-18 is about 0 second), the rotational speed command signal Ns is calculated from the 33 point speed value to 33S. The actual rotational speed Ni of the propulsion motor decreases from t3: 33 point to t4: 43 point, and is decelerated and stopped with regenerative operation.
At this time, the propulsion motor simulation power PMCi is a signal for reducing the power value at the point t3: 33 to 0 at the point t5: 53, and is given to the butt d point in FIG.

  Further, the simulated charging power PBCs is given to the butt c point of the signal switching unit 32-14 in FIG. 8 (see also FIG. 7), and the battery charging power PBs = PBi from t3: 32 points to t5: 52 points is increased. Signal. Therefore, at the point d, the signal PBsiA = PBCs + PMCi obtained by adding the signal PBCs and the signal PMCi becomes the signal PBsiB via the signal time setting unit 32-15 (see also FIG. 7) in FIG. 8, and the matching e point in FIG. Given to. At the match point e, the charging power signal PBsiB is set as a set value, and a difference from the actual charging power PBi calculated by the calculation unit 32-2 (see also FIGS. 4 and 7) of FIG. 8 is obtained. Is used as a signal.

  In other words, when the rapid stop operation of the propulsion motor is performed at t3 in FIG. 9C, the actual load of the propulsion motor suddenly decreases to 0 in a short time from t3: 33 points to t4: 43 points. Then, the battery charging power PBs = PBi is increased from 32 0 to 32C power value (simulated propulsion motor power PMCi) at t3, and during the period from t3 to t5, from t3: 33 power value to t5: Charging power signal obtained by adding 53 points of 0 signal (propulsion motor simulated power PMCi) and t3: 32 points of 0 to t5: 52 point of increasing power value (simulated charging power PBCs) Since the battery is charged by PBsiB, the battery charging power increases from 0 at 32 points to the power value at 32C points at t3, then decreases over time, and the operating state before t0 at t5: 52 points Return to.

In addition, the load on the generator and prime mover slowly decreases from t3: 31 point to t5: 51 point while supplying auxiliary power PAXi (indicated by 34 points of t3), and the prime mover is rotated by the follower control of the prime mover governor. Since the speed is kept constant, the motor speed does not increase.
That is, control is performed to suppress the sudden decrease in the generator load and the prime mover load by converting (appropriating) the reduced power of the propulsion motor power that has been suddenly reduced by the rapid stop operation into the charge power of the battery as simulated power. .

In addition, since the decrease in the propulsion motor power generated by the above rapid stop operation is converted (applied) to the charging power of the battery to absorb sudden power fluctuations, the battery voltage becomes the specified value by the charging operation. In order not to exceed it, the simulation power signal PMCi is reduced so that the generator voltage VGI does not exceed the generator voltage upper limit value shown in FIG.
By this voltage limiting operation, an overvoltage of the power feeding circuit voltage is prevented, so that a stable operation of the equipment / device fed from the power feeding circuit is secured, and the safety of the electric propulsion system is secured.
In addition, in the control method described above that corresponds to the sudden stop operation of the propulsion motor, the sudden decrease from the power value immediately before the stop command in the propulsion motor power is stored as “simulated power” and charging operation is being performed in the “constant power charge” mode. For this battery, the charging power is increased by “simulated power” and the charging operation is performed to prevent the generator load from rapidly decreasing, thereby mitigating the sudden decrease in the prime load.

In the case of the conventional “constant current charging” mode or “constant voltage charging” mode as a control method corresponding to such a sudden stop operation of the propulsion motor, for example, the receiving end voltage immediately before the stop command (FIGS. 7 and 8). M point voltage (INV input voltage)) or input current (current IM (INV input current) in FIGS. 7 and 8) is stored. In the case of “constant current charging”, the input current is added to the charging current. In the case of “voltage charging”, a control method in which the generator voltage is fixed with the memorized receiving-end voltage can be considered.However, in such a control method, it is promoted during its operation (during constant current charging or constant voltage charging). When a sudden decrease in power occurs, the battery voltage fluctuates and the battery power (battery charging power) fluctuates, so that the generator output power fluctuates, that is, the fluctuating battery current as described above. Or battery voltage If people reference (fixed), the other one is so will be controlled by the calculated value, the control operation becomes complicated, there is a possibility that the stability of the control may be impaired.
In this regard, in the present invention, as control for applying the reduced power of the propulsion motor to the battery charge power as a simulated power during the sudden stop operation of the propulsion motor, the deviation between the actual charge power value and the charge power set value is zero. The charging power control unit that adjusts the generator voltage at the same time allows the charging operation to be performed with the actual charging power value itself as the control amount (feedback amount) based on the charging power setting value to which the simulated power is applied. Highly stable control can be realized with a circuit.

5). Floating operation The floating operation of the battery is a charging operation in which the battery charging / discharging current is maintained at 0 A. FIG. 9D shows the operation pattern of the motor priority mode during the floating operation.
Select “constant power” with the charge changeover switch 19 (COSB) (see also FIGS. 7 and 8) shown in FIG. 4, and select with the priority changeover switch 20 (COSM) (see also FIGS. 7 and 8) of FIG. “Motor” priority is selected, and PBs of the battery power setting unit 23 (VRPB) (see also FIGS. 7 and 8) in FIG. 4 is set to “0”.
Since the charging power PBs = 0 in the battery floating operation, the generator supplies power to the propulsion motor and the auxiliary machine.

In this operation, assuming that the auxiliary machine power PAXi is substantially constant, the load fluctuations of the generator and the prime mover are governed by fluctuations in the propulsion motor power.
As described above, the power fluctuation of the propulsion motor occurs when the rotation speed of the propulsion motor is changed from low speed → high speed, high speed → low speed, or when it is stopped → running and running → stopped. The load fluctuations of the generator and the prime mover during the floating operation are the same as in the case of the sudden stop operation of the propulsion motor described in the above item 4-2, and the largest is due to the emergency stop operation of the propulsion motor.

In the floating operation by the normal operation, if the speed signal time setting unit 32-18 shown in FIG. 7 is set to a change time corresponding to a gradual change, the propulsion motor rotational speed gradually increases, decelerates, starts and stops. Since the load of the propulsion motor changes slowly, the constant rotation speed is maintained by following the governor governor control.
However, when the propulsion motor is rapidly stopped, the load on the propulsion motor is reduced in a short time, and the rotational speed of the prime mover increases rapidly due to the follow-up delay of the prime mover drive control.
An operation pattern during motor priority / battery floating operation will be described with reference to FIG. 9D.

  When a quick stop operation of the propulsion motor is performed at t3 in FIG. 9D, the propulsion motor speed setting signal changes from the speed value at 33 points to 0 at 32 points at t3, and the load PMi corresponding to the actual rotational speed Ni of the propulsion motor. Decreases from the power value at t3: 33 to 0 at t4: 42 in a short time, and the load on the generator and the prime mover rapidly decreases from t3: 31 to t4: 41. When the prime mover drive control cannot follow this sudden load fluctuation, the rotational speed of the prime mover increases rapidly, but by performing the same control as described in the section of the electric motor rapid stop operation, The rotational speed of the prime mover can be prevented from increasing.

When the calculation unit 32-9 shown in FIG. 8 (see also FIGS. 4 and 7) detects a rotational speed difference ΔNi (that is, a state where ΔNi = Ni−Ns> α), the switch 32- 10 (see also FIG. 7) is operated, and the simulated power generating unit 32-11 and the determining unit 32-12 (see also FIG. 7) shown in FIG. 8 are operated.
The simulated power generation unit 32-11 stores the actual power PMi when the switch 32-10 is operated, and outputs a simulated power signal PMCi that decreases from t3: the power value at the point 32C to 0 at the t5: 52 point. Further, because of the floating operation, the charging power setting PBs = 0 and the simulated charging power PBCs = 0 of the simulated power generator 32-11 = 0, so only the PMCi is output from the simulated power generator 32-11.
Therefore, since PBs = 0 and PBCs = 0 and the result of the match operation at the match c point in FIG. 8 (see also FIG. 7) is 0, the output signal PBsiA at the match d point in FIG. 8 to which the signal PMCi is input. PBsiA = PMCi, and this signal PBsiA (= PMCi) becomes a signal PBsiB via the signal time setting unit 32-15 (see also FIG. 7) of FIG. 8, and this is set as the charging power set value at the matching point e in FIG. The feedback control is performed based on the difference from the actual charging power PBi that is input and calculated by the calculation unit 32-2 of FIG. 8 (see also FIGS. 4 and 7).
The operation will be described with further reference to FIG. 9D.

That is, if the propulsion motor is rapidly stopped at t3 in FIG. 9D, the rotational speed setting signal decreases from the speed value at 33 points to 0 at 33S at t3, and the electric power corresponding to the actual rotational speed Ni of the propulsion motor. PMi drops from the power value at t3: 33 point to 0 at t4: 43 point, and the propulsion motor stops.
In order to avoid this sudden load fluctuation, based on the simulated power PMCi stored in the simulated power generator 32-11 (see also FIG. 7) at t3, the charging power PBi is t3 as the charging power set value PBsiB = PMCi. The charge power is converted from 0 at 32 points to a charge power value at 32 C points, and then reduced to 0 at t5: 53 with time.

In other words, the load fluctuation of the generator and prime mover without simulated power control decreases rapidly from t3: 31 point to t4: 41 point, but the simulated power control causes the power value at t3: 31 (power value at 32C point) (PMi) +34 point power value (PAXi)) t5: By gradually reducing the power value (PAXi) at 51 points, the motor speed can be kept constant by drive control tracking control. There will be no increase in motor speed.
When the battery voltage exceeds a predetermined value due to this charging operation, the simulated power signal PMCi is lowered so that the generator voltage VGI does not exceed the generator voltage upper limit value shown in FIG. The charging power is reduced to prevent the battery voltage and the power supply circuit from becoming overvoltage.

6). Motor stop operation To stop the motor for any reason, stop the motor and the generator. Two methods are conceivable as the stop operation.
A) If the circuit breaker 11 (SWG) (see Fig. 4) provided in the generator output circuit is set to “OFF” in advance of the stop operation of the prime mover, either stop the prime mover or A method of operating the motor stop almost simultaneously.
B) A method of stopping the generator after stopping the prime mover.

In the former method A, when the circuit breaker of the generator output circuit is “disconnected”, the load on the generator and the prime mover is instantaneously unloaded. For this reason, the prime mover governor control cannot follow the sudden load reduction, and the prime mover rotational speed is once increased and then stopped.
The method B stops the generator after stopping the prime mover, and does not cause a sudden load fluctuation in the prime mover. Therefore, the rotational speed of the prime mover does not increase at all, and it can be said that this is a preferable stop operation method for the prime mover.

An operation pattern by the method B is shown in FIG.
Now, when the generator control device receives the prime mover stop signal Egg at the point t0 in FIG. 11, the generator control device continues to supply the generator field current IGf once held at the point t0 to the generator. On the other hand, the rotational speed of the prime mover decreases toward the stop due to the fuel cut by the prime mover. Generator voltage VG at this time is proportional to the rotational speed n _eg of the generator driving motor (i.e. VGαn _eg × IGf), it decreases with the decrease of the engine rotational speed.

When the generator voltage decreases and reaches the point t1, the generator voltage VGI decreases from the battery voltage VB and VB> VGi, so that the diode rectifier 8 (Di) provided on the generator output side (see FIG. 4) ) Causes the generator output current IGI to be 0 A, that is, no load. Naturally, the prime mover and the generator are in no load at the point t1, so the circuit breaker 11 (switch SWG) (see Fig. 4) is turned off at the point t2 after the point t1, and the generator operation is stopped at the point t3. If this is done, the prime mover can be stopped without shock.
In addition, when a short circuit accident occurs in the generator circuit, the power feeding circuit, etc., and the circuit breaker 11 (SWG) performs the “break” protection operation due to the overcurrent detection, the above series of operations are not performed.

7). Application Example FIG. 10 shows an application basic circuit of a two-system system configuration using the method of the present invention.
The two-system system is composed of two batteries, two generators, two propulsion motors, and two auxiliary machines, and the system controller 32 corresponding to this configuration is commonly used for two-system power calculations. Power calculation unit 32-C, two generator control units 32-G (1) and 32-G (2), and a common motor control unit S2-M.

Since the basic operation is the same as that described above, only the differences will be described below.
A) Charging operation for “constant voltage”, “constant current”, and “constant power” The charging method for the two batteries is selected by the charge switch 19 (COSB). Due to differences in impedance, the charging voltage, charging current, and charging power of the two batteries are not the same. Therefore, control is performed on the basis of the larger detection value of the two batteries.

B) When the operation of supplying electric power with two generators is performed, the load fluctuations of the generator and the prime mover due to the operation and stop of the propulsion motor are large in the operation with small battery charging power.
In particular, when the operating state of the propulsion motor is changed from a heavy load at a high rotational speed to a light load at a low rotational speed, the generator load and the prime mover load rapidly decrease from the heavy load to the light load. At this time, since the occurrence of an unstable phenomenon due to the prime mover governor control performance in a state where the generator and the prime mover operated in parallel are in a light load, it is desirable to avoid the unstable phenomenon.

According to Reference 2 (Japanese Patent Laid-Open No. 2008-079357), in a system in which a plurality of generators driven by a prime mover (prime motor driven generator) are connected, the number of generators operated is changed according to the load. Therefore, a method for ensuring stable operation of the system has been proposed. Here, when the occurrence of instability reduction with light load is predicted in parallel operation of two prime mover-driven generators, power is supplied by one generator with one of the two units in a standby state, A method of returning to parallel operation of two units when a heavy load is reached has been proposed.
Therefore, also in the present invention, when a light load is generated using the technique described in Reference Document 2, one generator voltage in two generators is reduced and provided on the output side of each generator. As a no-load standby state by the block of the rectifier diode thus produced, an unstable phenomenon is avoided by supplying stable power by operating another generator.

For example, if it is assumed that the light load conditions for stable parallel operation of two motor-driven generators are 25% (50% in total), the calculation unit 32 shown in FIGS. 7 and 8 (see also FIG. 4). -1 generator output power PGi is detected to be 25% or less, and the voltage of the selected generator is reduced to enter a no-load standby state as a rectifier diode block state.
The generator to be set in the standby state is selected by the generator selection switch 26C (CSG) shown in FIG. 10, for example, when switched to 1, the first generator reduces the voltage when the load becomes light, In the no-load standby state by the rectifier diode block, power is supplied by operating one No. 2 generator.

  DESCRIPTION OF SYMBOLS 1 ... Battery (B), 2, 10, 16, 18 ... Voltage detector, 3, 9, 15, 17 ... Current detector, 4 ... Motor | power_engine (DE), 5 ... Generator (G), 6 ... Generator Excitation device (EX), 7 ... Excitation coil, 8 ... Rectifier (Di), 11 ... Circuit breaker (SWG), 12 ... Propulsion motor (M), 13 ... Speed detector (TD), 14 ... Power converter (INV) ), 19, 20, 24, 27 ... changeover switch, 21-23, 25, 26, 28, 32-20, 32-23 ... setter, 29-31 ... indicator lamp, 32 ... system control device, 32-C ... Power calculation unit, 32-G ... Generator control unit, 32-M ... Motor control unit, 32-1 to 32-8 ... Calculation unit, 32-9 ... Rotational speed state detection unit, 32-10, 32-19 ... Switch, 11-11 ... Simulated power generation unit, 32-12, 32-13 ... Distinction unit, 32-14, 32-17 ... Signal switching unit, 32-15, 32-18 ... Time setting unit, 32-16 ... rotation speed limiting portion, 33 ... auxiliary equipment.

Claims (10)

In an electric propulsion system that is a hybrid connection power source composed of a battery and a generator that charges the battery, and supplies power to the propulsion motor and auxiliary equipment while charging the battery with the generator,
A charging power control unit that adjusts the generator voltage so that the deviation between the actual charging power value and the set charging power value is zero, and the charging operation of the constant power charging method by this charging power control unit has been made possible. A generator control system characterized by   A battery voltage detector for detecting a charging voltage actual value, a battery current detector detector for detecting a charging current actual value, and a product of the charging voltage actual value and the charging current actual value is output as the charging power actual value. The generator control method according to claim 1, further comprising a charging power calculation unit.   A charging voltage controller that adjusts the generator voltage so that the deviation between the actual charging voltage value and the charging voltage setting value is zero; and the deviation between the actual charging current value and the charging current setting value is zero. A charging current control unit for adjusting a generator voltage; a constant voltage charging method by the charging voltage control unit; a constant current charging method by the charging current control unit; and a constant power charging method by the charging power control unit; The generator control method according to claim 2, wherein the charging operation of the three types of charging methods can be selectively executed.   While charging from the initial charging to the final charging is performed by a multi-stage constant power charging method in which the charging power set value is decreased step by step as the charging progresses, the charging time is shortened and the generator capacity The control method of the generator as described in any one of Claims 1-3 which suppresses the increase in these.   Two priority modes, a battery priority mode and a motor priority mode, are provided as selectable modes in the constant power charging method. When the battery charge power increases in the battery priority mode, the propulsion motor rotation is within the generator output limit. The electric power obtained by reducing the speed is applied to the battery charging power, and when the propulsion motor power increases in the motor priority mode, the battery charging power is reduced by adjusting the charging power setting value within the generator output limit. The generator control method according to claim 3 or 4, wherein the electric power obtained in this way is applied to propulsion motor electric power.   6. The off mode for canceling the two priority modes is provided, and in this off mode, the battery can be charged by any one of the constant voltage, constant current, and constant power charging methods. Generator control system.   Control of the prime mover governor device that keeps the rotational speed of the generator driving motor that drives the generator constant follows the load fluctuation that occurs when the propulsion motor is operated from stop to operation or from operation to stop. The generator control method according to any one of claims 1 to 6, wherein the rotation speed change time of the propulsion motor can be set so as to be able to.   When a rapid stop operation of the propulsion motor is performed, the reduced power of the propulsion motor generated by the rapid stop is temporarily applied to the battery charge power as a simulated power, and based on the charge power set value to which the simulated power is applied The charging operation by the charging power control unit is performed to suppress a sudden load fluctuation applied to the generator driving prime mover so that the control of the prime mover governor device can be followed. The generator control method according to any one of the above.   When the battery voltage exceeds a predetermined value when performing the charging operation by the charging power control unit based on the charging power setting value to which the simulated power is applied, the generator output voltage does not exceed the limit voltage value. The generator control method according to claim 8, wherein the charging power set value is lowered.   In stopping the generator driving prime mover, the generator load is detected by detecting that the generator load has become unloaded, and a sudden load decrease of the generator driving prime mover is avoided. The control method of the generator as described in any one of Claims 7-9.

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