JP5169436B2 - Control system for ship electric propulsion system - Google Patents

Description

The present invention, the storage battery (hereinafter, also referred to as cells) and, from the hybrid power supply with a generator for charging the 蓄 battery, supplying power to the propulsion motor and auxiliary machine for rotating the propeller to drive the ship ship It is related with the operation control system of the ship electric propulsion system which was made to operate.

In a ship electric propulsion system in which power is supplied to a propulsion motor and an auxiliary machine that rotate a propeller that propels a ship from a hybrid power source including a battery and a generator that charges the battery to operate the ship. As an operation mode related to power supply, an operation mode in which the generator supplies charging power to the battery and also supplies power to the propulsion motor and auxiliary equipment. Power is supplied to the propulsion motor and auxiliary equipment from both the generator and battery. And an operation mode in which the generator is stopped and electric power is supplied from only the battery to the propulsion motor and the auxiliary machine.
When the generator performs battery charging traveling (hereinafter also referred to as charging traveling) for operating the ship while supplying charging power to the battery and also supplying power to the propulsion motor and auxiliary machinery, the battery charging power, the propulsion motor It is necessary to operate so that the total power of the power and the auxiliary power does not exceed the generator output capacity (generator output limit value), that is, the generator output upper limit.
In this case, when increasing the charging power, the total electric power is operated so as to reduce the rotation speed of the propulsion motor so that it does not exceed the upper limit of the generator output. It must be operated to reduce the charging power of the battery so that the output upper limit is not exceeded.

  The reason is that when an operation that exceeds the upper limit of the generator output is performed, for example, when the total power reaches the upper limit of the generator output by increasing the charging power while charging with the constant current charging method. Because the generator output is limited by the limiting function and the specified charging current cannot flow, the constant current control circuit may run away due to feedback signal mismatch in constant current feedback control by matching the current setting value with the actual charging current. Occur. For this reason, the operator must perform careful monitoring and operation so that control runaway does not occur.

Moreover, as an example of the examination of an electric propulsion system equipped with, for example, a lithium ion battery as a high-performance battery instead of a conventional battery such as a lead-acid battery as the battery performance increases, for example, there is the one shown in Patent Document 1 .
Lead-acid batteries are charged with a large current at the beginning of charging, and from the middle to the end of charging, the generation of hydrogen gas and oxygen gas that accompanies electrolysis of the electrolyte is suppressed, and charging power loss is reduced. Since charging is performed with a small current, a long time is required for charging.

In contrast, lithium-ion batteries have no gas generation and good charging efficiency, so they can be charged with a large charging current in the entire charging range from the beginning of charging to the end of charging. However, when a lithium ion battery is used as a battery in a hybrid power source installed in a ship electric propulsion system and a large charging current is allowed to flow in the entire charging range of the battery, the charging time is shortened. The problem is to increase the capacity of the generator in the hybrid power source and to increase the size and cost of the generator.
JP-A-2005-080318

  In view of the above, the problem to be solved by the present invention is that the generator output capacity during charging traveling of the marine electric propulsion system equipped with a hybrid battery including a storage battery and a generator for charging the storage battery. Even if the charging current change operation of the storage battery exceeding the (generator output limit value) or the rotation speed change operation of the propulsion motor is performed, the control error does not occur and the labor of the operator is reduced. This is to suppress the increase in size and cost associated with the increase in capacity of the generator when a lithium ion battery is used as a storage battery to shorten the charging time.

In order to solve the above-described problems, the present invention provides a propulsion system for propelling a ship from a hybrid power source including a storage battery and a generator for charging the storage battery. In a ship electric propulsion system that supplies power to rotating propulsion motors and auxiliary equipment to operate the ship, the generator supplies charging power to the storage battery and also operates the ship while supplying power to the propulsion motor and auxiliary equipment. When performing battery charge running, the battery priority mode for controlling the power supply from the generator to give priority to the supply of charging power to the storage battery within the generator output limit value and the propulsion motor within the generator output limit value Switching means with the motor priority mode that controls the power supply from the generator to give priority to the power supply of Flip and in what you want to do any of modes, the switching when you select cell priority mode by means, charging power charging power increases, propulsion motor power, the total power of the auxiliary power generator output limit value Is exceeded, control is performed so that the surplus power obtained by reducing the propulsion motor rotation speed to decrease the propulsion motor power is applied to the increased charge power, and the switching means controls the motor priority mode. If the propulsion motor power increases due to an increase in the propulsion motor rotation speed and the total power exceeds the generator output limit value, the surplus power obtained by reducing the charge power is increased. The control means for controlling to apply to the propulsion motor power for a minute is provided, and by this control means, the battery priority mode and the motor priority mode are controlled. The total power is configured to control so as not to exceed the generator output limit value even the deviation (the invention of claim 1).
According to the first aspect of the present invention, in the battery charging traveling, the operation of changing the charging current of the storage battery so that the total power of the charging power, the propulsion motor power, and the auxiliary power exceeds the generator output limit value, or Even when the rotation speed change operation of the propulsion motor is performed, since the total power is controlled so as not to exceed the generator output limit value, it is possible to prevent the control runaway from occurring, and during battery charging traveling The labor of the operator can also be reduced.

According to the first aspect of the present invention, in battery charging traveling, for example, the battery priority mode or the motor priority mode is selected based on the state of charge of the storage battery, the operating condition of the ship, and the like. Further, the operation in the optimum mode, that is, the optimum charging of the storage battery or the optimum operation of the propulsion motor can be performed within the generator output limit value.
In addition, even when the battery is charged with the maximum charge power (charging current) that can be supplied in the current operating state in order to shorten the charging time during battery charging, the charging power and the propulsion motor are always charged. Since the total power of the power and auxiliary power is controlled so as not to exceed the generator output limit value, it is possible to ensure stable operation without causing control runaway, so lithium as a storage battery in a hybrid power source Even when an ion battery is used to reduce the charging time by charging with a large current, the required generator capacity can be kept small, resulting in an increase in generator capacity, size, and cost. Can not be.

Furthermore, in the control system of the ship electric propulsion system according to claim 1 , in the state where the charging power is increased and the propulsion motor power is zero when the control means selects the battery priority mode. When the auxiliary power is increased, the charging power is reduced, and when the electric motor priority mode is selected, when the auxiliary power is increased while the propulsion motor power is increased and the charging power is zero. The propulsion motor power can be reduced (invention of claim 2 ).
In any operation state of the ship, it is necessary to maintain the function of the auxiliary machine for the operation of the ship electric propulsion system. According to the invention of claim 2 above, Since the supply of electric power required by the auxiliary equipment can be reliably maintained, the ship electric propulsion system can be stably operated, and the reliability of the ship electric propulsion system can be improved.

Further, in the control system for a ship electric propulsion system according to any one of claims 1 and 2 , the storage battery may be a lithium ion battery (invention of claim 3 ).
For lead-acid batteries, the charging current must be reduced at the end of charging out of the entire charging process from the beginning of charging to the end of charging due to prevention of generation of hydrogen gas and oxygen gas accompanying electrolysis of the electrolyte. Although there are restrictions on the magnitude of the current, lithium-ion batteries can be charged with a large current over the entire charging process from the beginning of charging to the end of charging, and any of the charging processes (charging state) In this case, the charging current can be arbitrarily selected from a large current to a small current. Therefore, according to the third aspect of the invention, by using a lithium ion battery as the storage battery constituting the hybrid power source, the generator can be used regardless of whether the charging process of the storage battery at that time is from the initial charge stage to the final charge stage. Because the storage battery can be charged with the maximum charging power (charging current) that can be supplied in relation to the operating state of the propulsion motor and auxiliary equipment within the output limit value, a conventional battery such as a lead storage battery was used. Compared to the configuration, the charging time of the storage battery in battery charging traveling can be further shortened.

In the third aspect of the invention, when the battery priority mode is selected, priority is given to the supply of charging power to the storage battery, and the charging process of the storage battery at that time is from the beginning of charging to the end of charging. Even so, the storage battery can be charged with the maximum charge power (charge current) that can be supplied as surplus power minus the auxiliary machine power within the generator output limit value, thereby shortening the charge time Can be achieved.
Further, in the invention of claim 3 , when the motor priority mode is selected, priority is given to the supply of power to the propulsion motor, but the propulsion motor is in a low rotational speed state depending on the operational state of the ship, Each time the propulsion motor power goes to a low level, the surplus of the propulsion motor power and auxiliary power within the generator output limit value, regardless of whether the storage battery charging process at that time is from the beginning of charging to the end of charging. The storage battery can be charged with the maximum charging power (charging current) that can be supplied as electric power, whereby the charging time can be shortened.

  According to the present invention, in battery charging traveling in which a generator operates a ship while supplying charging power to the storage battery and also supplying power to the propulsion motor and auxiliary equipment, charging power to the storage battery is within the generator output limit value. "Battery priority mode" that controls the power supply from the generator to give priority to the supply of power, and the power supply from the generator to give priority to the power supply to the propulsion motor within the generator output limit value By changing the operation mode to “motor priority mode”, it is possible to change the charging current of the storage battery or the rotation of the propulsion motor so that the total power exceeds the generator output limit value. Even when a speed change operation is performed, control is performed so that the total power does not exceed the generator output limit value, so control runaway can be prevented. It is also possible to reduce the effort of both the operator.

In battery charging, for example, the battery priority mode or the motor priority mode is selected based on the state of charge of the storage battery, ship operating conditions, etc., and the optimal charging of the storage battery or the optimal propulsion motor is selected. The operation can be performed within the generator output limit value.
In addition, even when the battery is charged with the maximum charge power (charging current) that can be supplied in the current operating state in order to shorten the charging time during battery charging, the charging power and the propulsion motor are always charged. Since the total power of the power and auxiliary power is controlled so as not to exceed the generator output limit value, it is possible to ensure stable operation without causing control runaway, so lithium as a storage battery in a hybrid power source Even when an ion battery is used to reduce the charging time by charging with a large current, the required generator capacity can be kept small, resulting in an increase in generator capacity, size, and cost. Can not be.

FIG. 1 shows a configuration example of a ship electric propulsion system as an embodiment of the present invention.
In FIG. 1, a power generator composed of an AC generator 8 (G) (hereinafter also referred to as “generator”) driven by a prime mover 7 (DE) and a rectifier 10 (REC), and a battery 1 ( B) constitutes a hybrid power supply. The DC output side of the rectifier 10 (REC) in the power generator and the battery 1 (B) are connected to the DC power supply bus 101, and the AC output power of the AC generator 8 (G) is converted to DC by the rectifier 10 (REC). It is converted and supplied to the DC power supply bus 101 as output power of the power generator. In addition, 9 in FIG. 1 is an exciting coil of AC generator 8 (G).
Among the operation modes related to power supply in the ship electric propulsion system, in the operation mode of “charging traveling”, the output power of the power generator is supplied to the battery 1 (B) as charging power via the DC power supply bus 101. The propulsion motor 13 (M) and the auxiliary machinery 4 are also fed. The propulsion motor 13 (M) is connected to the DC power supply bus 101 via the power converter 15 (INV). The power conversion device 15 (INV) is configured by an inverter, converts DC power from the power generation device to AC, and supplies AC power to the propulsion motor 13 (M) configured by an AC motor.

Further, as shown in FIG. 1, the ship electric propulsion system is provided with a system control device 29 for controlling the ship electric propulsion system. The system controller 29 includes switches 18 (COSB), 21 (CSG), 23 (COSC), 27 (CSM), setting devices 19 (VRVA), 20 (VRIB), 22 (VRPG), setting devices. 28 (VRNM), indicator lamp 24 (PLGL), 25 (PLBL), 26 (PLML), voltage detector 2 (VDB), 5 (VDAX), 11 (VDG), 16 (VDM), current detector 3 ( SHB), 6 (SHAX), 12 (SHG), a current detector 17 (SHM), and a speed detector 14 (TD) are provided.
FIG. 2 is a control block diagram of the ship electric propulsion system. As shown in FIG. 2, the system controller 29 further includes a voltage control circuit 52, a current control circuit 55, a speed control circuit 62, A generator control circuit 65 and arithmetic units 29A to 29E, 57, 58, 60, 63 are provided.

The generator 8 driven by the prime mover 7 has a constant output limiting characteristic as shown in FIG. 3, and is controlled so that the generator output does not exceed the limit value when the load increases. In addition, since the battery voltage fluctuates depending on the battery charge state, when controlling the generator output voltage following the fluctuating battery voltage, the generator voltage VG × generator from the generator voltage VG substantially equal to the battery voltage VB. The output current IG is limited by the generator current upper limit value IGL (= PGS ÷ VG) so that the generator output PG, which is the amount calculated by the current IG, does not exceed the generator output upper limit PGS. As shown in FIG. 4, the required power PM of the propulsion motor 13 that drives the propeller changes in proportion to the cube of the rotational speed N (PM （N ³ ), and the auxiliary power PAX is a substantially constant fixed load. It is.

  On the other hand, there are two types of battery charging: a “constant current charging method” that charges with a constant charging current and a “constant voltage charging method” that charges with a constant voltage. Since it is performed by voltage, the charging power is adjusted by adjusting the charging current according to the generator voltage. Further, since the propulsion motor power PM is proportional to the cube of the rotational speed N, the propulsion motor power PM is adjusted by the rotational speed N. Based on these points, the following will be described.

1) Battery priority mode In the battery priority mode, the control changeover switch 23 (COSC) shown in FIGS. 1 and 2 is switched to the battery priority side.
If the battery charging current is increased, the charging power PBi = VBi × (+) IBi ((+) is charged, (−) is discharging) increases, and the total power PΣ (= PBi + PAXi) of the load power increases. Since + PMi) increases, the generator output PGi increases.

Battery charging current (+) IB (+ IB is charging current and −IB is discharging current) is expressed by the following equation.
(+) IB = (VG−VB) ÷ RΣ = [VG− (EB + (+) IB × RB)] ÷ RΣ
Where VG: Generator voltage
VB: Battery terminal voltage
(+) IB: Charging current
EB: Internal electromotive voltage
RB: Battery internal resistance
PB: Battery charge power = VB x IB
RΣ: Sum of charging circuit resistance

That is, if the generator voltage VG is lowered, the battery charging current IB is reduced, so that the charging power PB = VB × IB is also reduced.
On the other hand, when the generator voltage VG is lowered in the circuit shown in FIG. 1, the receiving end voltage on the propulsion motor 13 side is also lowered, but the propulsion power PM of the propulsion motor 13 whose rotational speed is controlled is as shown in FIG. Since the speed changes in proportion to the cube of the rotational speed N (PM∝N ³ ), the propulsion power PM does not change when the rotational speed of the propulsion motor 13 is controlled to a constant value.
Accordingly, since the propulsion motor power PM does not change even when the power receiving end voltage decreases, the propulsion motor input current IM increases.

If the charging voltage setting value VBS or the charging current setting value IBS is increased by operating the charging voltage setting device 19 (VRVB) or the charging current setting device 20 (VRIB) of FIGS. 1 and 2, the charging power PBi is obtained. To increase.
Here, the basic operation of the “battery priority mode” will be described.
The battery charging power PBi, propulsion motor power PMi, auxiliary power PAXi, and generator output PGi shown in FIGS. 1 and 2 are the voltages detected by the voltage detectors and current detectors provided in the circuits. And current are calculated by the calculation unit 57 (PBi = VBi × IBi), the calculation unit 63 (PMi = VMi × IMi), the calculation unit 58 (PAXi = VAXi × IAXi), and the calculation unit 60 (PGi = VGi × IGi). Is done.

As described above, the charging travel is an operation in which the generator supplies power to the propulsion motor and auxiliary equipment while supplying charging power (charging current) to the battery. Therefore, in a normal operation state, the calculation unit 29A in FIG. The total value PΣ (= PBi + PAXi + PMi) shown in the equation (1) is within the range where the set output PGS of the generator output upper limit setting device 22 (VRPG) shown in FIGS. 1 and 2 is the upper limit value. Thus, the engine is operated in a state of PGS ≧ PGi = PΣ.
The generator output upper limit value PGS is set as shown in FIG. 3 (a) by the generator output upper limit setting unit 22 (VRPG) shown in FIGS. 1 and 2, as shown in FIG. The generator currents IGL1, IGL2, IGL3, IGL4,... Shown in FIG. 3 (b) from the generator voltage VGi that changes due to fluctuations in VBi are expressed by equation (4) “IGL = PGS ÷ VGi” in the arithmetic unit 29A of FIG. Then, this value is given to the generator control circuit 65 as the generator upper limit current value IGL, and the generator output current IGI is limited to perform the generator output limiting operation.

  Note that the generator output upper limit value PGS may be operated so as to be set to a level suitable for the operating state of the generator driving motor at that time, for example. That is, the prime mover 7 (DE) in the power generation apparatus may be operated in a state where the output is limited in response to a change in the state of the combustion system, the governor system, or the like. Even if the operation of the prime mover 7 is not satisfactory, the battery charge from the generator 8 (G) is charged to the extent possible by setting the generator output upper limit value PGS to a level corresponding to the operating state of the prime mover 7 at that time. The state where electric power can be supplied can be reliably maintained, and the operation of the ship electric propulsion system can be made more stable.

FIG. 5A is an operation explanatory diagram for explaining an example of the operation pattern of the battery priority mode (battery priority mode 1), and mainly shows the operation in the case where the charging power (charging current) is constant during the charge traveling. It is shown. 5A, since the propulsion motor 13 is stopped before the time t0 and the propulsion motor power PMi is zero (= the power level at the point 03), the battery charging power PBi and the auxiliary power are generated by the generator power PGi. PAXi is supplied.
When the rotational speed of the propulsion motor 13 is gradually increased from time t0, the propulsion motor power PMi gradually increases, and the total power PΣ = PBi + PMi + PAXi gradually increases.
Further, since the generator output upper limit PGS> the generator output PGi = the total power PΣ is between the times t0 and t1, the generator supplies predetermined power to the battery, the propulsion motor, and the auxiliary machine.
As a specific operation when the rotational speed of the propulsion motor 13 is gradually increased as described above, for example, the following operation method can be used.

(A) A setting operation for gradually increasing the setting value NS itself of the rotation speed setting device 28 (VRNM) from time t0 is performed, and the rotation speed command value NSC is also increased correspondingly. By the rotational speed feedback control using NSC as a set value, the rotational speed Ni gradually increases following the rotational speed command value NSC.
(B) The set value NS itself of the rotation speed setter 28 (VRNM) is set to the final target rotation speed value as a step command operation at time t0, and in response to this, the soft start function in the system controller 29 Therefore, the rotation speed command value NSC is controlled to gradually increase, and the rotation speed feedback control using this rotation speed command value NSC as a set value causes the rotation speed Ni to gradually increase following the rotation speed command value NSC. To do. Here, the soft start function is based on a rotational speed command adjusting means (not shown) provided in the system control device 29. This rotational speed command adjusting means is a rotational speed setting device 28 (VRNM). Based on the set rotational speed set value NS, a rotational speed command signal NSC that changes in time with a set slope corresponding to each control mode of acceleration control and deceleration control is formed.

  Further, when the propulsion motor rotation speed is increased, the propulsion motor power PMi increases, and when time t1 is reached, the total power PΣ becomes a point 11 that coincides with the generator output upper limit PGS. At this time, the battery charging power PBi is operated at the point 12, the propulsion motor power PMi is operated at the point 13, and the auxiliary power PAXi is operated at the point 14. The operation state at the time t1 is an operation state of the expression (PGi−PΣ = 0), 3) expression “PGS = PGi” of the calculation unit 29A in FIG. 2, and the expressions (2) and (3) The battery charge power PBi at point 12 is stored as PBm, and the propulsion motor power PMi at point 13 is also stored as PMm, and the generator output PGi has reached the limit value (upper limit value PGS). Is displayed with indicator lamp 24 (PLGL). Further, the rotational speed command value NSC given to the point m1 of the rotational speed feedback control system of the propulsion motor 13 at this time t1 is stored as NSCm. This stored value NSCm is a rotation speed value corresponding to the stored value PMm of the propulsion motor power.

The solid line pattern after time t1 in FIG. 5A shows an operation with a constant charge power, and the charge power PBi is the same as the charge power PBm at time t1 after time t1, so that (5) of the calculation unit 29B in FIG. From the equation, PBi−PBm = ΔPBi = 0, the propulsion motor electric power is similarly PMi = PMm−ΔPBi = PMm from the equation (6), and the propulsion motor rotational speed command value is from the equation (7) of the calculation unit 29D of FIG.
NSC = NSCm × (PMi ÷ PMm) ^1/3 = NSCm × (PMm ÷ PMm) = NSCm. Accordingly, after the time t1, the same rotational speed command value NSC (= NSCm) as the propulsion motor rotational speed command value NSCm at the time t1 is output as a set value from the system controller 29, and the rotational speed is obtained at the point m1 shown in FIG. The generator output limit control is realized by performing rotation speed feedback control in combination with the detection signal Ni.

Here, when the charging current increases by ΔPBi from the stored charging power PBm as shown by the dotted line pattern after time t1 in FIG. 5A, when the increase ΔPBi is to be applied by the decrease in the propulsion motor power, The propulsion motor power may be reduced by lowering the propulsion motor rotation speed. In this case, since the relationship between the propulsion motor rotation speed and the propulsion motor power is indicated by P∝N ³ as shown in FIG. 4, based on the stored propulsion motor power PMm and the propulsion motor rotation speed command value NSCm, FIG. Corresponding to the propulsion motor electric power value PMi (= PMm−ΔPBi) reduced by the electric power to be applied to the increase ΔPBi of the charging electric power from the equation (6) of the arithmetic unit 29B and the equation (7) of the arithmetic unit 29D Propulsion motor rotation speed value,
NSC = NSCm x (PMi ÷ PMm) Obtained by calculating ^1/3 , and if this rotational speed value is used as the command value NSC and driving the propulsion motor at a reduced speed, the surplus due to the reduction in propulsion motor power The increased charging power ΔPBi can be applied with the power.

Further, in the solid line pattern of FIG. 5A, the charging power PBi after time t1 is constant, and therefore, from the equations (5), (6) and 29 (D) of the calculation unit 29B of FIG.
Since PBi−PBm = ΔPBi = 0, PMi = PMm, NSC = NSCm × (PMi ÷ PMm) ^1/3 = NSCm, the rotational speed command value NSC (= the rotational speed Ni of the propulsion motor) does not change. The propulsion motor power PMi is kept constant at the power value at point 13.
When driving while charging the battery at a constant current after time t1, the battery voltage gradually increases as charging progresses, and the battery charge power PBi = battery voltage VBi × charge current IBi increases as shown by the dotted line in FIG. 5A. The charging power PBi is increased by ΔPB = ΔVB × IBi (where the increase amount of the battery voltage VBi is ΔVB).

However, since the generator output has already reached the upper limit value PGS at time t1, in order to apply the increase ΔPBi of the charging power, the expression (6) of the calculation unit 29B and (7) of the calculation unit 29D in FIG. The propulsion motor rotational speed command value NSC corresponding to the propulsion motor electric power value reduced by the electric power to be applied to the increase ΔPBi of the charging electric power is calculated from the equation, and the propulsion motor is operated accordingly.
Further, when the auxiliary machine power PAX increases in the process of this operation state, the PGS in the expression (1) of the calculation unit 29A in FIG. 2 under the condition of “battery priority” (condition in which the charging power PBi is not changed). = PGi = PΣ = PBi + PAXi + PMi The propulsion motor power value PMX = decreased by ΔPAXi corresponding to the increase ΔPAXi of the auxiliary power PAXi according to the equation (12) of the arithmetic unit 29B of FIG. While obtaining PMi-ΔPAXi and setting PMi = PMX in equation (7) of the calculation unit 29D in FIG. 2, NSC = NSCm × (PMX ÷ PMm) ^1/3 propulsion motor rotation speed command corresponding to propulsion motor power value PMX The value NSC is calculated, the propulsion motor is operated at the command value NSC, and the decrease in the propulsion motor power is applied to the increase ΔPAXi in the auxiliary machine power.

FIG. 5B is an operation explanatory diagram for explaining an example (battery priority mode 2) in which the operation pattern of the battery priority mode is different, mainly the operation when charging power (charging current) is increased during charging traveling. Is shown. Since the basic operation is the same as that of FIG. 5A described above, different operations will be described below.
Before the time t0, the ship electrical propulsion system is operated with the charging power PBi at point 02, the propulsion motor power PMi at point 03, the auxiliary power PAX at point 04, and the total power PΣ at point 01.
The charging power PBi gradually increases by the setting operation of the charging voltage setting device 19 (VRVB) or the charging current setting device 20 (VRIB) from time t0, and reaches the power value at point 12 at time t1.

  At time t1, the total power PΣ becomes a point 11 that coincides with the generator output upper limit PGS. At this time, the battery charging power PBi is operated at the point 12, the propulsion motor power PMi is operated at the point 13, and the auxiliary power PAXi is operated at the point 14. The operation state at the time t1 is the operation state of the expression (PGi−PΣ = 0) and (3) expression “PGS = PGi” of the calculation unit 29A in FIG. 2, and the expressions (2) and (3 ), The battery charge power PBi at point 12 is stored as PBm, and the propulsion motor power PMi at point 13 is stored as PMm, and the generator output PGi has reached the limit value (upper limit value PGS). Is indicated by indicator light 24 (PLGL). Further, the rotational speed command value NSC given to the point m1 of the rotational speed feedback control system of the propulsion motor 13 at this time t1 is stored as NSCm. This stored value NSCm is a rotation speed value corresponding to the stored value PMm of the propulsion motor power.

When the setting device 19 or 20 is further operated to increase the charging power, the expression (PBi−PBm = ΔPBi) of the calculation unit 29B in FIG. 2 becomes larger than 0, and the calculation unit 29B in FIG. (6) From the expression “PMi = PMm−ΔPBi ≧ 0”, the propulsion motor electric power value PMi reduced by the electric power to be applied to the increase ΔPBi of the charging electric power is obtained, and (7) of the calculation unit 29D in FIG. The propulsion motor rotation speed command value NSC calculated from the formula “NSC = NSCm × (PMi ÷ PMm) ^1/3 ” is output from the system control device 29 and corresponds to the electric power to be applied to the increase ΔPBi of the charging power The propulsion motor is operated at a rotational speed reduced by that amount.

The charging power PBi further increases from the point 12 at time t1 and reaches the charging power upper limit point 22 at time t2, but the propulsion motor power PMi (propulsion motor rotation speed) gradually decreases from the point 13 at time t1 ( Propulsion motor power PMi = 0 (propulsion motor rotation speed = 0) at point 23 at time t2.
That is, the generator that has already reached the output upper limit only supplies battery charging power PBi and auxiliary power PAXi at time t2, and cannot supply power to the propulsion motor. That is, at this time, PMi = 0 and PGi = PBi + PAXi in the equation (1) of the arithmetic unit 29A in FIG. As described above, the charging voltage command value VBSC or the charging current command value IBSC cannot be increased on the condition that the charging power has reached the upper limit of the point 22 and the propulsion motor power PMi = 0. The indicator light 25 (PLBL) indicates that the charging power has reached the upper limit.

  In the process of charging the battery by the constant current charging method after time t2, the charging power increases as the charging proceeds and the charging voltage rises. However, in the state where the generator output has already reached the output upper limit PGS, FIG. Due to the generator output limiting operation described in (a) and (b), the current limit value IGL obtained from the expression (4) “IGL = PGS ÷ VGi” of the calculation unit 29A in FIG. Since the generator output current is limited, the charging power cannot be increased.

  Of course, after the time t2, the rotation speed command NSC is held at 0, so the propulsion motor rotation speed is held at 0. The generator at this time is in an operating state in which power is supplied only to the battery and the auxiliary machine. When the auxiliary machine power PAX increases from this state, the calculation unit 29A in FIG. In order to prevent PΣ from changing in the relationship of PGS = PGi = PΣ = PAXi + PBi based on the equation (1), only ΔPAXi corresponds to the increase ΔPAXi of the auxiliary power PAXi from Equation (13) of the arithmetic unit 29B of FIG. The reduced charging power value PBX = PBi−ΔPAXi is calculated, and in the case of constant voltage charging, the voltage command value VBSC is calculated as PBi = PBX with the expression “VBSC = PBi ÷ IBi” of the arithmetic unit 29E of FIG. In the case of constant current charging, the current command value IBSC is calculated as PBi = PBX in the equation (11) “IBSC = PBi ÷ VBi” of the calculation unit 29E of FIG. Surplus to give to point b1 or b2 in Fig. 2 and apply to the increase ΔPAXi of auxiliary power Reducing the charging power so that the power obtained.

When the charging power PBi is decreased from the point 32 at time t3, the surplus power ΔPBi (= PBm−PBi) due to the decrease in the charging power obtained by the equation (5) of the calculation unit 29B in FIG. 2 is supplied to the propulsion motor. The propulsion motor will resume operation.
When the charging power PBi further decreases and passes the point 42 at time t4, the total power PΣ becomes smaller than the generator output upper limit value PGS, so that the stored PBm, PMm, and NSCm are reset to return to the normal operation.

2) Motor priority mode The motor priority mode is an operation mode when the control changeover switch 23 (COSC) shown in FIGS. 1 and 2 is switched to the motor priority side.
When the propulsion motor rotation speed is increased, the propulsion motor power increases and the total power PΣ reaches the generator output limit value PGS. Further, the charging power reduction operation for applying the increased amount when the propulsion motor power increases will be described with reference to FIGS. 1, 2, 6A and 6B.

FIG. 6A is an operation explanatory diagram illustrating an example of an operation pattern (motor priority mode 1) in the motor priority mode. In the operation of FIG. 6A, the propulsion motor is stopped (power level at point 03) before time t0, and the generator supplies power to the battery and the auxiliary machine.
When the rotational speed setter 28 (VRNM) is operated from time t0 to increase the rotational speed set value NS, the propulsion motor starts operation and the rotational speed increases.
Since the generator output upper limit PGS> the generator output PGi = the total power PΣ during the period from time t0 to t1, the system controller 29 outputs the command value NSC having the same value as the rotation speed set value NS, and the actual rotation at the point m1. Rotational speed feedback control is performed by matching with the speed detection signal Ni.
Further, when the rotation speed set value NS is increased, the propulsion motor rotation speed is increased and the propulsion motor power PMi reaches point 13, the propulsion motor power PMi at point 13, the battery charge power PBi at point 12, and the complement of point 14 The total power PΣ (point 11) with the machine power PAXi matches the generator output upper limit PGS.

When the total power PΣ reaches the point 11 (PGS = PΣ) that coincides with the generator output upper limit PGS, the battery charging power PBi at the point 12 is obtained on the condition of the expressions (2) and (3) of the arithmetic unit 29A in FIG. Is stored as PBm, and the propulsion motor power PMi at point 13 is stored as PMm. Further, the rotational speed command value NSC given to the point m1 of the rotational speed feedback control system of the propulsion motor 13 at this time t1 is stored as NSCm. This stored value NSCm is a rotation speed value corresponding to the stored value PMm of the propulsion motor power.
Before the time t1, the battery is charged with a constant power, so PMi−PMm = ΔPMi is calculated from equation (8) of the calculation unit 29C in FIG. 2, and PBi = PBm−ΔPMi is calculated from equation (9). .
When the rotational speed set value NS is further increased from the point 13, the rotational speed increases and the propulsion motor power PMi increases, and the increase ΔPMi is obtained from the equation (8) of the calculation unit 29C of FIG. From the equation, the charging power value PBi = PBm−ΔPMi decreased by the amount of power to be applied to the increase ΔPMi of the propulsion motor power is calculated.

Depending on whether the battery is charged by “constant voltage charge” or charged by “constant current charge”, the “constant voltage charge” is calculated by the expression (10) of the calculation unit 29E in FIG. To obtain the voltage command value VBSC (= PBi ÷ IBi), and in “constant current charging”, obtain the current command value IBSC (= PBi ÷ VBi) using equation (11) of the calculation unit 29E in FIG. Charge the battery according to the value.
The battery charging current (+) IB (+ IB is a charging current and −IB is a discharging current) at this time is expressed by the following equation as described above.
(+) IB = (VG−VB) ÷ RΣ = [VG− (EB + (+) IB × RB)] ÷ RΣ
Where VG is the generator voltage
VB: Battery terminal voltage
(+) IB: Charging current
EB: Internal electromotive voltage
RB: Battery internal resistance
RΣ: Sum of charging circuit resistance Therefore, if the charging current is adjusted by changing the generator voltage VG (≈battery voltage VB), the charging power PB can be adjusted.

2-1) In case of constant voltage charging operation When the rotational speed is further increased from point 13 at time t1 and the propulsion motor power PMi increases by ΔPMi from PMm, the power to be applied to the increase ΔPMi of the propulsion motor power In order to set the charging power value PBi = PBm−ΔPMi decreased by the corresponding amount, the voltage command value VBSC obtained by the expression (10) “VBSC = PBi ÷ IBi” of the calculation unit 29E in FIG. Voltage feedback control is performed by matching with the detected value VBi.
That is, the electric power to be applied to the increase ΔPMi of the propulsion motor electric power is obtained from the equation (10) of the calculation unit 29E of FIG. 2 and given to the butt point b1, and charging power PBi = voltage VBi × charging The current IBi is controlled and obtained.

When the rotational speed increases and the propulsion motor power PMi gradually increases from point 13 at time t1 and reaches point 23 at time t2, the charging power gradually decreases from point 12 and becomes zero at point 22. At time t2, the generator supplies power only to the propulsion motor and the auxiliary machine. That is, since PGS = PGi = PΣ = PAXi + PMi (PBi = 0) in the expression (1) of the arithmetic unit 29A in FIG. 2, the increase in the propulsion motor power cannot be applied with the decrease in the charge power.
In the system controller 29, at time t2, the generator output PGi (= total power PΣ) reaches the upper limit value PGS and is restricted, and the charging power PBi is zero, that is, “PGi = PGS” and “ It is detected that the state of “PBi = 0” is reached, and the rotational speed command value NSC after time t2 is limited to the rotational speed command value NSC (t2) at time t2 as an upper limit. Thereby, after the time t2, even if the rotational speed setting value NS is increased to a level higher than the rotational speed setting value NS (t2) at the time t2 by the setting operation of the rotational speed setting device 28 (VRNM), the rotation speed Since the rotational speed command value NSC given to the speed feedback control system (point m1) is limited to the level of the rotational speed command value NSC (t2) at time t2, the actual rotational speed Ni of the propulsion motor is also at time t2. Is limited to the level of the rotational speed value Ni (t2) (≈NSC (t2)).

  In this way, the rotational speed command value NSC itself is limited to the level at the detection time point (time t2) at the time point (time t2) when the state of “PGi = PGS” and “PBi = 0” is detected. Is provided in the system control device 29 so that the rotation speed set value NS is raised to a higher level in a state where the power that can be supplied to the propulsion motor is restricted (after time t2). Even when an appropriate setting operation is performed, the propulsion motor rotational speed limit control can be performed without causing a control abnormality such as saturation of the control output of the rotational speed feedback control system.

Further, when the auxiliary machine power PAXi increases by ΔPAXi in this operation state, the battery charge power is already 0, and therefore, the increase ΔPAXi of the auxiliary machine power cannot be generated.
Therefore, in order to obtain ΔPAXi, the calculation unit 29B of FIG. 2 is set so that PΣ does not change in the relationship of PGS = PGi = PΣ = PAXi + PMi in the expression (1) of the calculation unit 29A of FIG. (15), the propulsion motor power value PMX = PMi−ΔPAXi decreased by ΔPAXi corresponding to the increase ΔPAXi of the auxiliary machine power PAXi is calculated. In the expression (7) of the calculation unit 29D in FIG. As PMi = PMX,
NSC = NSCm × (PMX ÷ PMm) The system controller 29 outputs the rotation speed command value NSC calculated by ^1/3 to reduce the rotation speed of the propulsion motor and compensate for the decrease in the propulsion motor power. Appropriate amount of increase in machine power ΔPAXi.

  When the propulsion motor rotational speed set value NS is decreased from time t3 toward the zero speed at time t5, the propulsion motor power PMi decreases from point 33 at time t3 toward point 53 at time t5, and this propulsion motor power PMi Can be supplied as the charging power of the battery, so that charging of the battery is resumed. At time t4, the charging power PBi becomes constant at the power value at the point 42. Therefore, the generator output restriction by the upper limit value PGS is released, and the stored values PMm, PBm, NSCm at the time t1 are reset to normal. Return to the operating state.

2-2) Case of Constant Current Charging Operation The basic operation is the same as the above-described “constant voltage charging” operation, and therefore the different operation will be described below.
The operation of storing the charging power PBi at point 12 at time t1 in FIG. 6A as PBm, the propulsion motor power PMi at point 13 as PMm, and storing the rotational speed command value NSC at time t1 as NSCm is the same as described above.
When the propulsion motor power is increased by further increasing the rotational speed from the point 13, an increase ΔPMi = PMi−PMm is obtained from the equation (8) of the calculation unit 29C in FIG. 2, and (9) of the calculation unit 29C in FIG. ) To obtain the charging power value PBi = PBm−ΔPMi reduced by the amount of electric power to be applied to the increase ΔPMi of the propulsion motor power, and the charging power is charged from the formula (11) of the calculation unit 29E of FIG. A current command value IBSC (= PBi / VBi) for obtaining the power value PBi (= PBm−ΔPMi) is obtained, and this current command value IBSC is given to the b2 butt point, and current feedback control with the actual charging current IBi is performed. To do.

When propulsion motor power PMi further increases from point 13 at time t1 and reaches point 23 at time t2, charging power PBi gradually decreases from point 12, and charging power PBi = 0 at point 22 at time t2. . Further, the fact that the propulsion motor power PMi has reached the limit value at the point 23 at time t2 is displayed by the indicator lamp 26 (PLML).
At time t2, since the generator is in an operating state in which power is supplied only to the propulsion motor and the auxiliary machine, PGS = PGi = PΣ = PAXi + PMi (PBi = 0) in equation (1) of the arithmetic unit 29A in FIG. The increase in the propulsion motor power PMi can no longer be generated by the decrease in the charge power.

When the time t2 is reached, the propulsion motor rotation speed command NSC is limited so that it cannot be increased on the condition that the charging power PBi = 0 (charging current IBi = 0), and the propulsion motor power PMi is limited to the power value at point 23; The output of the generator is limited by the current limit value IGL (= PGS ÷ VGi) obtained by equation (4) of the calculation unit 29A in FIG.
The operation when the auxiliary power PAXi increases in this operating state is the same as described above.
Thereafter, if the propulsion motor rotational speed set value NS is decreased from time t3 toward the zero speed at time t5, the propulsion motor power PMi decreases from point 33 at time t3 to point 53 at time t5. Since the decrease in power PMi can be supplied as charging power for the battery, charging of the battery is resumed. At time t4, the charging power PBi becomes constant at the power value at the point 42. Therefore, the generator output restriction by the upper limit value PGS is released, and the stored values PMm, PBm, NSCm at the time t1 are reset to normal. Return to the operating state.

Figure 6B is an operation explanatory diagram for explaining an example of different operation patterns of the electric motor priority mode (motor priority mode Part 2). The basic operation of FIG. 6B is the same as the operation of FIG. 6A described above. The difference is that at time t0, the propulsion motor is in the operating state at point 03, the battery is in the charging operation at point 02, and the propulsion motor rotational speed setting value NS is determined from the rotational speed value corresponding to the power value at point 03 at time t0. The increased operation is shown.
When the propulsion motor power PMi increases and reaches point 13 at time t1, the propulsion motor power PMi at point 13 is stored as PMm, the battery charging power PBi at point 12 is stored as PBm, and the rotational speed command value at time t1 The operation of storing NSC as NSCm is the same as described above.

When the propulsion motor rotation speed set value NS is further increased from time t1, the increase ΔPMi = PMi−PMm of the propulsion motor power is obtained from the equation (8) of the calculation unit 29C in FIG. 2, and the calculation unit 29C in FIG. (9), the charging power value PBi = PBm−ΔPMi decreased by the power required to be applied to the increase ΔPMi of the propulsion motor power is obtained, and the charging power is calculated from the formula (11) of the computing unit 29E in FIG. Current command value IBSC = PBi ÷ VBi for obtaining the charging power value PBi (= PBm−ΔPMi) is obtained, and current feedback control is performed by matching the current command value IBSC with the actual charging current IBi at point b2. .
When the propulsion motor power PMi further increases from point 13 at time t1 and reaches point 23 at time t2, the charging current gradually decreases from point 12 and becomes charging current IBi = 0 at point 22 at time t2. .
At time t2, since the generator is in an operating state in which power is supplied only to the propulsion motor and the auxiliary machine, PGS = PGi = PΣ = PAXi + PMi (PBi = 0) in equation (1) of the arithmetic unit 29A in FIG. The increase in propulsion motor power can no longer be generated by the decrease in charge power.

Further, at time t2, on the condition of charging power PBi = 0 (charging current IBi = 0), the propulsion motor rotation speed command NSC is restricted so as not to increase, and the propulsion motor power PMi is restricted to the power value at point 23. At the same time, the output of the generator is limited by the current limit value IGL = PGS ÷ VGi obtained by the equation (4) of the calculation unit 29A in FIG. The operation when the auxiliary power PAXi increases in this operating state is the same as described above.
Thereafter, if the propulsion motor rotational speed set value NS is lowered from time t3, the propulsion motor power PMi decreases from the point 33 at time t3 to the point 53 at time t5, and the decrease in the propulsion motor power PMi is reduced by the battery. Since charging power can be supplied, charging of the battery is resumed. At time t4, the charging power PBi becomes constant at the power value at the point 42. Therefore, the generator output restriction by the upper limit value PGS is released, and the stored values PMm, PBm, NSCm at the time t1 are reset to normal. Return to the operating state.

3) The above-mentioned items 1) and 2) have described the “battery priority mode” and the “motor priority mode” as the operation mode during charging according to the embodiment of the present invention. By charging the battery in consideration of the state of charge of the battery and the operating state of the propulsion motor and auxiliary equipment within the machine output limit value, it becomes possible to perform efficient charging with a shortened charging time. As a result, the operation time of the prime mover drive generator (engine drive generator) in the hybrid power source is shortened and the consumption of fuel for the prime mover (engine) is reduced, so that a great economic effect is obtained.
In the “motor priority mode”, the propulsion motor can be operated at a high speed within the generator output limit value, and more power can be supplied to the propulsion motor if the battery is in a floating operation. Therefore, higher speed operation becomes possible.

  Here, the above floating operation is performed in the battery groups B1 to Bn in which a plurality of cells such as lithium ion batteries as shown in FIG. 9 are connected in series as the battery 1 (B) constituting the hybrid power source in FIG. (In FIG. 9, only one cell is representatively shown.) However, the semiconductor switches Q1 to Qn and the discharge diodes D1 to Dn are connected in parallel to the DC power supply bus 101 via a switch circuit connected in antiparallel. In the marine electric propulsion system to which the battery power supply device 1 having the following configuration is applied, the semiconductor switches Q1 to Qn are turned OFF, and the generator voltage VG is set to the highest voltage voltage among the battery voltages VB1 to VBn of each battery group, for example. By controlling to a slightly higher voltage (= battery voltage + diode layering voltage + α voltage), the generator voltage VG is blocked by the diodes D1 to Dn in the reverse bias state, and the negative voltage of the generator 8 (G) In this operation, the charging / discharging current is set to 0 A (no charging current or discharging current flows) without being affected by disturbance due to load fluctuation. Since the generator voltage VG decreases when the generator 8 (G) is stopped, the battery groups B1 to Bn start discharging through the diodes D1 to Dn, and power supply to the load is started. Instantaneous power supply is possible. Note that the α voltage is desirably determined in consideration of a voltage fluctuation value associated with a control response of the generator 8 (G) due to a load fluctuation disturbance. In FIG. 9, the battery power supply device 1 includes current detectors SH1 to SHn and voltage detectors VD1 to VDn, and ON-OFF commands Q1dv to Qndv for the semiconductor switches Q1 to Qn are given from the system controller 29. It is done. The switch circuit provided for each battery group is not limited to the configuration of FIG.

  As described above, from a hybrid power source provided with a battery and a generator for charging the battery, a ship that feeds a propulsion motor and an auxiliary machine that rotates a propeller that propels the ship to operate the ship. In the electric propulsion system, the battery priority mode and the motor priority mode are used for the charging operation that operates the ship while the generator supplies the battery with charging power and also supplies the propulsion motor and auxiliary equipment. By properly using these, the ship electric propulsion system can be operated efficiently, effectively, and flexibly.

4) Next, charging characteristics and a charging method of a conventional battery such as a lead storage battery and a new battery such as a lithium ion battery will be described with reference to FIG.
FIG. 7 is an explanatory diagram showing an example of battery charging characteristics. As described above, the lead-acid battery has a step 1 (large constant current: shown in FIG. 7) for reasons such as prevention of generation of hydrogen gas and oxygen gas accompanying electrolysis of the electrolyte and reduction of charging power loss. PBC1), step 2 (constant voltage / medium current: PBC2), and step 3 (small constant current: PBC3) are charged by changing the charging current, so charging requires a long time.

  On the other hand, the lithium ion battery can be charged with a large constant current over the entire charging process (the entire charging region) from the initial charging stage to the final charging stage, so that the maximum chargeable current LBCm as shown in FIG. Charging is completed at time t1 (Cm (FULL)), charging is completed at time t2 if charging current LBC1, and charging time t3 if charging current LBC2. Lithium-ion batteries can be charged by arbitrarily selecting the magnitude of the charging current from a large current to a small current, regardless of which process (charged state) of all the charging processes. When the ship electric propulsion system having a configuration using a lithium ion battery as the battery 1 (B) in FIG. 1 is charged and run, the generator is used regardless of whether the charging process of the battery 1 at that time is from the initial charging stage to the final charging stage. Since the battery 1 can be charged with the maximum charging power (charging current) that can be supplied in relation to the driving state of the propulsion motor and the auxiliary machine within the output limit value, a conventional type such as a lead storage battery can be used. Compared to the configuration using a battery, the charging time can be greatly shortened.

Further, in the case of a conventional battery such as a lead storage battery, it takes a long time to charge in the fully charged region from the latter half of Step 2 to Step 3, but in the case of a lithium ion battery, for example, in FIG. As shown by C13 and C14, the charging time can be further shortened by charging with a constant current LBC1 irrespective of the charging amount. Here, C11, C12, C13, and C14 in FIG. 7 are codes representing the state of charge of the battery. For example, C11: 20%, C12: 40%, C13: 60%, C14: 80%, C1 : 100% (fully charged). When the lithium ion battery is charged with a constant current LBC1 regardless of the charge amount, the charge amount can be determined by the battery voltage LBV.
Further, the dotted line IG shown in FIG. 7 is the upper limit of the generator output current, and when the battery is charged with the charging current LBC1, the electric power corresponding to the current of the magnitude of (IG-LBC1) is supplied to the propulsion motor and the auxiliary machine. If the charging current is LBC2, the power corresponding to the current of (IG−LBC2) can be supplied to the propulsion motor and auxiliary equipment. If the charging current is changed from LBC1 to LBC2, the propulsion motor And more electric power can be supplied to the auxiliary machine.

In the ship electric propulsion system using a lithium ion battery as a battery constituting the hybrid power supply, when the “battery priority mode” is selected, the supply of charging power to the battery is prioritized. Regardless of whether the battery charging process is from the beginning of charging to the end of charging, the battery is charged with the maximum charging power (charging current) that can be supplied as surplus power minus the auxiliary power within the generator output limit value. Accordingly, the charging time can be shortened.
On the other hand, in the ship electric propulsion system using a lithium ion battery as a battery constituting the hybrid power source, when the “motor priority mode” is selected, priority is given to the supply of power to the propulsion motor. Every time the propulsion motor is in a low rotation speed state and the propulsion motor power is in a low level state depending on the operation state, the generator output limit value is used regardless of whether the battery charging process at that time is from the beginning of charging to the end of charging. The battery can be charged with the maximum charging power (charging current) that can be supplied as surplus power obtained by subtracting the propulsion motor power and auxiliary machine power, thereby shortening the charging time.

As described above, when a lithium ion battery is used, the operations of the “battery priority mode” and the “motor priority mode” that make the best use of the characteristics of the lithium ion battery are possible. Although partially overlapping with the description of 6B, a series of operations will be described with reference to FIG.
FIG. 8 is an operation explanatory diagram for explaining an operation example of the battery priority mode and the motor priority mode. First, in the “battery priority mode”, when the charging power is increased from point 02 at time t0 to point 22 at time t2, the total power PΣ increases from point 01 to point 21.
If the charging power between points 22 and 32 is not changed, the total power PΣ = generator output PGi <generator output upper limit PGS, so the generator supplies predetermined power to the propulsion motor and auxiliary equipment. doing.
When charging power is increased from point 32 at time t3 to point 52 at time t5, the total power PΣ coincides with the generator output upper limit PGS at point 41 at time t4, and charging power PBi at point 42 is stored as PBm. Then, the propulsion motor power PMi at point 43 is stored as PMm, and the rotational speed command value NSC at time t4 is stored as NSCm.

Further, when the charging power is increased from the point 42, the propulsion motor power (rotational speed) is decreased (decreased) from the point 43 in the same manner as described above.
At time t5 when the charging power reaches the point 52, the total power PΣ = PBi + PMi + PAXi is the point 51 of the generator output upper limit PGS, and the propulsion motor power is the power value of the point 53 that is reduced from the point 43. When the charging power is constant at the power value at the point 52 during the period from the point 52 at the time t5 to the point 62 at the time t6, the propulsion motor is continuously operated at the power value (rotational speed) at the point 53. In FIG. 8, during the period from time t5 to time t6, the pattern of the propulsion motor power PMi and the pattern of the auxiliary power PAXi are drawn as the same power level. This is because the propulsion motor power PMi is the auxiliary power. The state in which the power is reduced to the same level as the power PAXi is schematically shown, and the actual operation pattern in this period is not limited to a configuration in which both have the same power value.
Further, when the charging power increases from the point 62 at the time t6 to the point 72 at the time t7, the propulsion motor power (rotational speed) is further decreased (reduced), and the surplus power is changed to an increase ΔPBi of the charging power. As a result, the propulsion motor power (rotational speed) becomes zero at point 73 at time t7.

At time t7, the generator is in a state of supplying only the battery charging power at point 72 and the auxiliary power at point 74, so that the charging power is further increased from the power value at point 72 after time t7. However, since it is no longer possible to generate the power to be applied to the increase in the charging power by the reduction (decrease) operation of the propulsion motor power (rotation speed), the charging power cannot be increased from the point 72.
Therefore, the charging power is limited using the charging current command value IBSC (t7) or the charging voltage command value VBSC (t7) at the point 72 as the upper limit value of the charging current command or the charging voltage command.
When the charging power is reduced from the point 82 at time t8 to the point 92 at time t9, the propulsion motor power (rotational speed) increases (rises) from point 83 to point 93, and after time t9, the charging power is reduced to point 92. If the power value is constant, the propulsion motor is operated at the power value (rotational speed) at point 93.

When the control changeover switch 23 (COSC) is switched from the “battery priority mode” to the “motor priority mode” at time t10, the propulsion motor power (rotation speed) is the same power (rotation speed) as the points 03 to 43. Then, the battery charging power is reduced to the power at the point 102, and the surplus power is allocated to the increase in the propulsion motor power.
When the propulsion motor power (rotational speed) is increased (increased) from the point 113 at time t11 to the point 123 at time t12, a decrease in charging power necessary to apply the increase in propulsion motor power is calculated. To reduce charging power. The charging power becomes 0 at a point 122 at time t12.

At this time t12, the generator is in a state of supplying only the propulsion motor power at point 123 and the auxiliary power at point 124. Therefore, after time t12, the generator tries to increase the propulsion motor power further than the power at point 123. However, since it is no longer possible to generate the electric power to be applied to the increase in the propulsion motor power by the reduction operation of the charging power, the propulsion motor rotation speed command value NSC (t12) at the point 123 is set to the propulsion motor rotation speed command. The upper limit of the propulsion motor speed is limited as an upper limit, thereby limiting the propulsion motor power.
When the propulsion motor power (rotational speed) is decreased (decreased) from point 133 at time t13 to point 143 at time t14, the battery charging power increases from point 132 to point 142.

When the control changeover switch 23 (COSC) is switched from the “motor priority mode” to the “battery priority mode” at the time t15, the “battery priority” operation is performed, so the charging state at the point 152 returns to the same state as the point 92 at the time t9. However, the operating state of the propulsion motor is limited to operation with the same power as point 93.
When the charging power is operated to decrease from point 162 toward point 182 at time t18 at time t16, the propulsion motor power (rotational speed) increases (increases) from point 163, and at time t17, points 03 to 43 The electric power (rotational speed) at the same point 173 is restored, and the generator output limitation by the upper limit value PGS is released at the point 171.
When the charging power becomes zero at point 182 at time t18, the generator supplies only propulsion motor power at point 183 and auxiliary power at point 184 at time t18.

When the generator is stopped at time t20, the propulsion motor power at point 203 and the auxiliary power at point 204 are supplied by the battery discharge power at point 201B.
In addition, since the operation state is limited to the generator output upper limit value PGS from time t4 to t17, during the time t5 to t10 in the “battery priority mode”, the battery charge is prioritized to suppress the propulsion motor power. Since the propulsion motor operation is prioritized and the battery charging power is suppressed during times t10 to t15 in the “motor priority mode”, the optimum operation according to the situation becomes possible.

The block diagram which shows the ship electric propulsion system as embodiment of this invention Control block diagram of ship electric propulsion system Limiting control characteristic diagram of generator output Characteristic diagram showing the relationship between propulsion motor rotation speed and propulsion power Operation explanatory diagram explaining battery priority mode 1 Operation explanatory diagram explaining battery priority mode 2 Operation explanatory diagram for explaining the motor priority mode 1 Operation explanatory diagram for explaining the motor priority mode 2 Illustration of battery charging characteristics Operation explanatory diagram explaining battery priority mode and motor priority mode Circuit diagram showing a configuration example of a battery power supply device

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Battery (B), 2, 5, 11, 16 ... Voltage detector, 3, 6, 12, 17 ... Current detector, 4 ... Auxiliary machine, 7 ... Motor | power_engine (DE), 8 ... Generator (G) , 9 ... exciting coil, 10 ... rectifier (REC), 13 ... propulsion motor (M), 14 ... speed detector (TD), 15 ... inverter (INV), 18, 21, 23, 27 ... switch, 19, 20 , 22, 28 ... setter, 24-26 ... indicator lamp, 29 ... system controller, 29A-29E, 57, 58, 60, 63 ... arithmetic unit, 52 ... voltage control circuit, 55 ... current control circuit, 62 ... Speed control circuit, 65 ... generator control circuit, 101 ... DC feeding bus.

Claims (3)

In a ship electric propulsion system that feeds a propulsion motor and an auxiliary machine that rotate a propeller that propels a ship from a hybrid power source including a storage battery and a generator for charging the storage battery, and operates the ship, Priority is given to the supply of charging power to the storage battery within the generator output limit value when the generator supplies the storage battery with charging power and also operates the ship while supplying power to the propulsion motor and auxiliary equipment. Switching between the battery priority mode for controlling the power supply from the generator and the motor priority mode for controlling the power supply from the generator to give priority to the power supply to the propulsion motor within the generator output limit value In what provides a means and executes any mode according to the switching ,
When the battery priority mode is selected by the switching means, if the charge power increases and the total power of the charge power, propulsion motor power, and auxiliary power exceeds the generator output limit value, the propulsion motor rotation speed is reduced. When the motor priority mode is selected by the switching means, the motor speed of the propulsion motor is controlled so as to apply the surplus power obtained by reducing the propulsion motor power to the increased charging power. When the total electric power exceeds the generator output limit value due to the increase in the propulsion motor power due to the rise in the power, the surplus power obtained by reducing the charge power is applied to the increased propulsion motor power. A control means for controlling,
A control method for a ship electric propulsion system, characterized in that the control means controls the total power so as not to exceed a generator output limit value in both the battery priority mode and the motor priority mode . When the battery priority mode is selected, the control means reduces the charging power when the auxiliary power increases when the charging power increases and the propulsion motor power is zero, and the motor priority 2. The ship according to claim 1 , wherein when the mode is selected, the propulsion motor power is decreased when the auxiliary motor power is increased in a state where the propulsion motor power is increased and the charging power is zero. Control method of electric propulsion system. The said storage battery is a lithium ion battery, The control system of the ship electric propulsion system in any one of Claim 1 or 2 characterized by the above-mentioned.

Images