JPH0993830A - Control method for charger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid overload of non-utility generator by detecting the AC power being fed to a charger from a non-utility generator and controlling the recovery charging amount of a battery such that the detected AC power does not exceed the rated capacity of non-utility generator while feeding power to a load from the charger. SOLUTION: A charger 10 is fed with AC power from a commercial power supply 1 when it is sound and fed with AC power from a non-utility generator 2 upon interruption of commercial power supply 1. The AC power is converted into DC power and fed to a battery 5 and a load 6. AC power being fed to the charger 10 from the non-utility generator 2 is detected and recovery charging amount of battery 5 is controlled such that the detected AC power does exceed the rated capacity of non-utility generator 2, i.e., the recovery charging amount of battery 5 is lower than a level corresponding to 0.1 times of the nominal capacity of battery 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control method for a charging device that converts AC power from a commercial power source or the like into DC power to supply power to a storage battery and a load.

[0002]

2. Description of the Related Art A conventional method for controlling a charging device of this type is as follows.
When the commercial power supply is healthy, AC power is supplied from the commercial power supply, the charging device converts this AC power to DC power to supply power to the storage battery and the load, and when the commercial power supply fails,
When this is detected, the operation of the charging device is stopped, and the load is supplied with power from the storage battery.

[0003]

However, according to the above-mentioned conventional method for controlling the charging device, the load is supplied from the storage battery when the commercial power source fails, so that the storage battery is discharged when the power failure continues for a long time. Reaching the final voltage,
At this time, there was a problem that power supply to the load had to be stopped.

If the capacity of the storage battery is increased in order to avoid the above problems as much as possible, the storage battery becomes large and expensive, and the capacity of the charging device also becomes large. Furthermore, in the case of a power supply system in which the commercial power supply supplies power to the charging device from the private power generation device, the private power generation device may be overloaded due to the amount of recovery charge from the charging device to the storage battery.

An object of the present invention is to provide a method for controlling a charging device which solves the above problems.

[0006]

According to the first aspect of the invention, when the commercial power source is healthy, AC power is supplied from the commercial power source, and when the commercial power source is out of power, AC power is supplied from the private power generator. In a charging device that converts this AC power into DC power to supply power to a storage battery and a load, when the charging device is supplied with AC power from a private power generation device, this AC power amount is detected and the charging device detects While supplying power to the load, the recovery charge amount of the storage battery is controlled so that the detected AC power amount does not exceed the rated capacity of the private power generation device.

According to a second aspect of the present invention, in the charging device, when the charging device is supplied with AC power from an in-house power generator, the charging device supplies power to the load while the storage battery has a nominal capacity of the storage battery. The control is performed so that the amount of recovery charge is equal to or less than 0.1 times. A third aspect of the invention is such that when the commercial power source is healthy, AC power is supplied from the commercial power source, and when the commercial power source is out of power, AC power is supplied from the private power generator, and the AC power is converted to DC power. To supply power to one storage battery and k (k ≧ n) loads.
= 2.3 ... n) charging devices, each of the n charging devices supplies power to the load when the n charging devices are supplied with AC power from the private power generation device. At the same time, the storage battery is controlled so as to have a recovery charge amount equal to or less than 0.1 times the nominal capacity of the storage battery.

Further, a fourth aspect of the present invention is, in the above n charging devices, when n-1 charging devices among the n charging devices are supplied with AC power from the private power generator, A predetermined time period is measured from the time when the supply of the alternating-current power from the power generation device is started, and when within the predetermined time period, each of the n-1 charging devices supplies a power to the load while the storage battery is a battery of the storage battery. Storage battery is controlled so that the amount of recovery charge is equal to or less than 0.1 times the nominal capacity, and after the predetermined time period has passed, each of the n-1 charging devices supplies power to the load. Control is performed so that the recovery charge amount of is gradually increased.

According to the present invention, even when the commercial power source is out of power, power is supplied from the private power generator to continue the operation of the charging device. At this time, the charging device supplies power to the load while suppressing the recovery charge amount of the storage battery. By performing the control to prevent the storage battery from reaching the final discharge voltage, it is also possible to prevent the private power generation device from being overloaded.

[0010]

1 is a block diagram of a charging device showing a first embodiment of the present invention. In FIG. 1, 1 is a commercial power source, 2 is a private power generator including a diesel generator, 3 is a distribution line to which AC power of either the commercial power source 1 or the private power generator 2 is fed, and 10 is a charging device. ,
Reference numeral 5 is a storage battery charged by the charging device 10, and 6 is a load of the charging device 10, which is, for example, an uninterruptible power supply device such as OA equipment. The charging device 10 includes a circuit breaker 11, a charger 12 including a thyristor, an automatic voltage regulator 13 (hereinafter, referred to as AVR 13) that controls the gate of the thyristor of the charger 12, and an output current of the charger 12. Shunt resistor 14 that detects a power failure, power failure detector 15 that detects a power failure at the input of charger 12, commercial power supply 1 is a distribution line 3 when a power failure occurs.
It is composed of a control circuit 16 for controlling the AVR 13 to a desired state by inputting the amount of power generated by the private power generator 2 that supplies power to the AVR 13, the voltage across the shunt resistor 14, and the output of the power failure detector 15. .

Usually, the AC power of the commercial power source 1 is fed through the distribution line 3, the charging device 10 converts the AC power into DC power, charges the storage battery 5 and feeds the load 6.
At this time, in order to prevent an excessive charging current from flowing depending on the state of the storage battery 5, the charging device 10 has a drooping characteristic that limits the current to a predetermined maximum value or less. The control operation of the charging device 10 will be described below with reference to the operation waveform diagram shown in FIG.

Until the time t ₁ shown in FIG. 2, the commercial power supply 1 is in a normal state, and the output current of the charging device 10 by the power supply from the commercial power supply 1 is the current of the load 6 and the minute current to the storage battery 5 (so-called floating). It shows the state that the charging current is flowing (Fig. 2
(C)) When a power failure occurs in the commercial power source ₁ at time t ₁ (FIG. 2 (a)), the power failure detector 15 detects this and the control circuit 16 sets the output current of the charger 12 to zero ( Figure 2
(C)). In this state, the load 6 is supplied with power from the storage battery 5.

When the start-up of the private power generator 2 is completed at time t ₂ and the power supply to the distribution line 3 is started from the private power generator 2 (FIGS. 2 (a) and 2 (b)), the amount of power generation rises. Comparing with each other, the control circuit 16 sets the output current of the charger 12 corresponding to the power generation amount of the private power generator 2, and gives the AVR 13 a command with the voltage across the shunt resistor 14 as the detected value. At this time, when the amount of power generated by the private power generation device 2 is the rated capacity, the control circuit 16 causes the charger 12 to be approximately equal to the rated capacity.
Output current is set. In this state, when the current of the charging device 10 and the discharge current from the storage battery 5 flow through the load 6 in relation to the required current of the load 6 (FIG. 2B),
In some cases, the current of the charging device 10 becomes the charging current (recovery charge amount) of the load 6 and the storage battery 5.

When the commercial power supply 1 is restored at time t ₃ , the power supply from the private power generator 2 to the distribution line 3 is stopped (see FIG. 2).
(A), (b)), the power failure detector 15 detects this, and the control circuit 16 makes the output current of the charger 12 zero (FIG. 2 (c)). In this state, the load 6 is supplied with power from the storage battery 5. When power is supplied from the commercial power supply 1 to the distribution line 3 at time t ₄ (FIG. 2A), the control circuit 16 causes the AVR 13 to operate.
Start flowing the output current of the charger 12 via the
(C)). At this time, as described above, if the discharge current flows from the storage battery 5 when the commercial power supply 1 is out of power, the charging current to the storage battery 5 becomes large and the output current of the charger 12 tends to become excessive. The drooping current value is limited by detecting the voltage across 14 (FIG. 2).
(C)).

FIG. 3 is a block diagram of a charging device showing a second embodiment of the present invention, and those having the same functions as those in FIG. 1 are designated by the same reference numerals. In FIG. 3, the charging device 20
Is the circuit breaker 11, the charger 12, the AVR 13, the shunt resistor 14, the power failure detector 15, the operation signal of the private power generator 2 that supplies power to the distribution line 3 when the commercial power source 1 fails, and the voltage across the shunt resistor 14. The control circuit 21 controls the AVR 13 to a desired state by inputting the output of the power failure detector 15 and the voltage across the shunt resistor 7 that detects the current of the storage battery 5.

The operation of the charging device 20 when the commercial power source 1 is healthy and after the commercial power source 1 is restored is similar to that of the charging device 10. When the commercial power source 1 has a power failure, the power failure detector 15 detects this and the control circuit 21 causes the output current of the charger 12 to be zero. In this state, the load 6 is supplied with power from the storage battery 5.

Next, when the start-up of the private power generator 2 is completed,
When the power supply to the distribution line 3 is started from the private power generator 2, the operation signal of the private power generator 2 is input to the control circuit 21, and the control circuit 21 sets the voltage across the shunt resistor 7 as the detected value,
An AV command is issued so that the detected value is equal to or less than the current corresponding to the amount of recovery charge corresponding to 0.1 times the nominal capacity of the storage battery 5.
Give to R13. At this time, the charging device 20 supplies power to the load 6 and controls the storage battery 5 so that the current is equal to or less than the current corresponding to the recovery charge amount. Current and the discharge current from the storage battery 5 flow (the recovery charge amount is zero at this time), the current of the charging device 20 becomes the charge current of the load 6 and the storage battery 5 (the recovery charge amount). In some cases

FIG. 4 is a configuration diagram of a charging device showing a third embodiment of the present invention, and those having the same functions as those in FIGS. 1 and 3 are designated by the same reference numerals. In FIG. 4, FIG.
A charging device 20 having the same function as the charging device 20 shown in FIG.
Two units a and 20b are provided, the load 6 is connected to the charging device 20a, and the load 8 is connected to the charging device 20b.

When the commercial power source 1 loses power, the charging device 20
The power failure detector 15 of each of a and 20b detects this,
The output current of each charger 12 is made zero by each control circuit 21. In this state, the loads 6 and 8 are fed from the storage battery 5. Next, when the start-up of the private power generator 2 is completed and the power supply from the private power generator 2 to the distribution line 3 is started, the control circuits 2 of the charging devices 20a and 20b, respectively.
1, the operation signal of the private power generator 2 is input, each control circuit 21 sets the voltage across the shunt resistor 7 as a detection value, and this detection value corresponds to 0.1 times the nominal capacity of the storage battery 5 A command is given to each AVR 13 so that the current becomes equal to or less than the current corresponding to. As a result, the maximum recovery charge amount of the storage battery 5 is a recovery charge amount corresponding to 0.2 times the nominal capacity of the storage battery 5.

When the rated capacities of the charging devices 20a and 20b are different from each other, the recovery charge amount corresponding to 0.2 times may be shared by the respective rated capacity ratios. FIG. 5 is a configuration diagram of a charging device showing a fourth embodiment of the present invention, and those having the same functions as those in FIGS. 1 and 3 are designated by the same reference numerals. In FIG. 5, two charging devices 30a and 30b are provided.

The operations of the charging devices 30a and 30b when the commercial power source 1 is healthy and after the commercial power source 1 is restored are the same as those of the charging device 10. When the commercial power source 1 has a power failure, the power failure detectors 15 of the charging devices 30a and 30b detect this, and the respective control circuits 31 make the output currents of the respective chargers 12 zero. In this state, load 6,
8 is supplied with power from the storage battery 5.

Next, when the start-up of the private power generator 2 is completed,
When power supply to the distribution line 3 is started from the private power generation device 2, the operation signal of the private power generation device 2 is input to the control circuits 31 of the charging devices 30 a and 30 b via the respective timers 32, and the respective control circuits 31 Uses the voltage across the shunt resistor 7 as a detection value, and issues a command to each AVR 13 such that the detection value is equal to or less than the current corresponding to the amount of recovery charge corresponding to 0.1 times the nominal capacity of the storage battery 5. give. As a result, the maximum recovery charge amount of the storage battery 5 is a recovery charge amount corresponding to 0.2 times the nominal capacity of the storage battery 5.

The above description of the operation is based on the description of the charging devices 30a, 30.
In the case where b operates normally, the charging device 3 will be described below.
The operation when one of 0a and 30b is stopped due to some trouble will be described. If a power failure occurs in the commercial power supply 1 while the charging device 30b is stopped, the power failure detector 15 of the charging device 30a detects this and the control circuit 31 of the charging device 30a outputs the output current of the charger 12. To zero. In this state, the loads 6 and 8 are fed from the storage battery 5.

Next, when the start-up of the private power generator 2 is completed,
When the power supply from the private power generator 2 to the distribution line 3 is started, the control circuit 31 of the charging device 30a is controlled by the output of the power failure detector 15 and the operation signal of the private power generator 2 via the timer 32 that starts time measurement. The operation signal of the private power generator 2 is input, and the control circuit 31 sets the voltage across the shunt resistor 7 as a detected value, and the detected value corresponds to a recovery charge amount corresponding to 0.1 times the nominal capacity of the storage battery 5. The following commands are given to each AVR 13. At this time, the charging device 30a supplies power to the loads 6 and 8 and controls the storage battery 5 so that the current becomes equal to or lower than the current corresponding to the recovery charge amount.
When the currents of the charging device 30a and the discharge current from the storage battery 5 flow in the loads 6 and 8 in relation to the required currents of the loads 6 and 8 (at this time, the recovery charge amount is zero), charging is performed. In some cases, the current of the device 30a becomes the charging current of the loads 6 and 8 and the storage battery 5 (the recovery charge amount).

In this state, when the above-mentioned timer 32 has passed a predetermined time, for example, one hour, the recovery charge amount is gradually increased and the discharge current of the storage battery 5 is decreased. If the commercial power supply 1 restores power while the timer 32 is measuring the one hour or after the measurement is completed, at that point, the charging device 30a shifts to the operation when the commercial power supply 1 is restored, and the charging device 30a operates. Within the range of the drooping current value, the power supply to the loads 6 and 8 and the charging current to the storage battery 5 are caused to flow.

[0026]

According to the present invention, even when the commercial power source is out of power, power is supplied from the private power generator and the operation of the charging device is continued while limiting the operating state, so that the overload of the private power generator is eliminated. The storage battery is prevented from reaching the discharge end voltage, and the storage battery is smaller and less expensive than conventional devices.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a charging device showing a first embodiment of the present invention.

FIG. 2 is a waveform chart illustrating the operation of FIG.

FIG. 3 is a configuration diagram of a charging device showing a second embodiment of the present invention.

FIG. 4 is a configuration diagram of a charging device showing a third embodiment of the present invention.

FIG. 5 is a configuration diagram of a charging device showing a fourth embodiment of the present invention.

[Explanation of symbols]

1 ... Commercial power source, 2 ... Private generator, 3 ... Distribution line, 5 ... Storage battery, 6, 8 ... Load, 7 ... Shunt resistance, 10, 20,
20a, 20b, 30a, 30b ... Charging device, 11 ... Circuit breaker, 12 ... Charger, 13 ... AVR, 14 ... Shunt resistor, 15 ... Blackout detector, 16, 21, 31, ... Control circuit, 32 ... Timer.

Claims (4)

[Claims] 1. When the commercial power source is healthy, AC power is supplied from the commercial power source, and when the commercial power source is in a power failure, AC power is supplied from the private power generation device, and the AC power is converted into DC power for storage batteries. In a charging device that supplies power to a load and a load, when the charging device is supplied with AC power from an in-house power generator, the AC power amount is detected, and the charging device supplies the load to the load while detecting the AC power. A method for controlling a charging device, which comprises controlling the amount of recovery charge of a storage battery so that the capacity does not exceed the rated capacity of the private power generation device. 2. When the commercial power source is healthy, AC power is supplied from the commercial power source, and when the commercial power source is in a power failure, AC power is supplied from the private power generator, and the AC power is converted to DC power and the storage battery is converted. In a charging device that supplies electric power to a load and a load, when the charging device is supplied with AC power from an in-house power generator, the charging device supplies electric power to the load and the storage battery supplies 0.1% of the nominal capacity of the storage battery. A control method for a charging device, characterized in that control is performed so as to be equal to or less than a recovery charge amount corresponding to double. 3. When the commercial power supply is healthy, AC power is supplied from the commercial power supply, and when the commercial power supply is out of power, AC power is supplied from the private power generator, and the AC power is converted into DC power. In n (n = 2 ... 3 ... n) charging devices that supply power to one storage battery and k (k ≧ n) loads, n charging devices supply AC power from the private power generation device. When receiving the battery, each of the n charging devices controls the storage battery so that the storage battery has a recovery charge amount equal to or less than 0.1 times the nominal capacity of the storage battery while supplying power to the load. A method of controlling a charging device, which is characterized. 4. When the commercial power source is healthy, AC power is supplied from the commercial power source, and when the commercial power source is out of power, AC power is supplied from the private power generator, and this AC power is converted into DC power to N (n = 2 ... 3 ... n) charging devices that supply power to one storage battery and k (k ≧ n) loads, n-1 charging devices out of n charging devices When the device is supplied with AC power from the private power generation device, a predetermined time period is measured from the time when the supply of AC power from the private power generation device is started, and within the predetermined time period, the n-1 units are measured. Each of the charging devices, while supplying power to the load, controls the storage battery to be equal to or less than the recovery charge amount corresponding to 0.1 times the nominal capacity of the storage battery, and after the predetermined time period has elapsed, Each of the n-1 charging devices stores electricity while supplying power to the load. The method of the charging device, characterized by a control so as to gradually increase the recovery charge of the pond.