JPH0441737Y2 - - Google Patents

Description

[Detailed description of the invention] A. Technical field of the present invention The present invention relates to an electrical circuit configuration for determining the quality of a storage battery in an uninterruptible device.

B. Conventional technology Regarding conventionally used uninterruptible devices, the third
To describe it with a diagram, the DC obtained by connecting a rectifier Rec such as a thyristor connected to an AC power source and a smoothing capacitor C to its output is converted back to AC by an inverter IV equipped with an automatic voltage adjustment function.
This power is supplied to a load L such as a computer, but since the rectifier Rec must have a float charge in the storage battery B connected to the input of the inverter IV, which supplements DC power during a power outage, The conduction angle is controlled by the thyristor control circuit CN', and the DC power can be finely adjusted. It's being used.

C. Problems with the prior art By the way, talking about the maintenance of storage batteries in uninterruptible devices, even with the circuit configuration shown in Figure 3, it is difficult to maintain a relatively large-scale system using stationary batteries. It is easy to determine whether the battery is good or not by periodically checking the voltage, specific gravity, etc. of each battery. Lead-acid batteries are widely used,
When such a sealed storage battery is used, its shape is a sealed structure, so
It is extremely difficult to judge whether the battery is good or bad, and especially when determining when to replace the battery at the end of its life, it is necessary to perform a discharge test. There are usually 10 cells per system, so if even one cell fails, the discharge characteristics will immediately deteriorate, and in extreme cases, it will no longer function as an uninterruptible device. At the same time as a power outage of the commercial power supply, the load voltage will suddenly drop, which will have an adverse effect on the load such as the computer.To avoid such a situation, it is necessary to actually discharge the battery as much as possible and inspect its condition. There is.

However, when performing such a check with the conventional device shown in Figure 3, it is common to force a power outage state while the uninterruptible device is operating, and discharge the battery. However, if a defective battery had already occurred at such a time, the output voltage of the uninterruptible device would drop abnormally, and the inconvenience of causing a negative impact on the load such as a computer shutdown could be avoided. First, as a practical matter, the battery discharge test in the forced power outage state during operation is troublesome, and has other drawbacks.

D. Purpose of the Proposal The purpose of the Proposal is to eliminate the shortcomings of the above.
The purpose of this is to easily perform a discharge test to determine the quality of storage batteries in uninterruptible equipment while operating under actual load, and even if a battery failure occurs, The purpose is to safely determine only battery failure without causing any trouble to the load side.

E. Main Points of the Proposal The present proposal consists of a voltage detector VD that is connected to storage battery B, constantly monitors the voltage, and outputs an output signal when the voltage drops to a predetermined potential; It is equipped with a time measuring device TA that measures the time interval until the voltage is received, and a thyristor control circuit CN that is configured to short-circuit the voltage dividing resistor of the built-in voltage detection section to obtain a predetermined switching voltage. Has characteristics.

F. Embodiment of the present invention Figure 1 is a block diagram showing the electrical connections in the embodiment of the present invention, and Figure 2 shows the discharge characteristics of the storage battery to explain the operation of the embodiment of the present invention. The same parts as shown in Fig. 3, which describes the conventional type, are given the same reference numerals, and only the features of the present invention are described together with Fig. 2, which shows the discharge characteristics of storage battery B. Time T is plotted on the vertical axis, and storage battery B
(the input voltage of the inverter, hereinafter also referred to as the P point voltage).
In the figure, CN is a thyristor control circuit equipped with a switching mechanism (not shown) configured to short-circuit the voltage dividing resistor in the internal voltage detection part to obtain a predetermined potential (switching voltage), which will be described later. It controls the normal conduction angle by applying pulses, and when the switching mechanism is operated, the DC output voltage is set to change from the normal value VN to the switching voltage VR. Used when conducting tests.

S is an interlocking switch that automatically starts the operation of an automatic timer to be described later when the switching mechanism is operated.

VD is a voltage detector connected to one pole of storage battery B, and is set in advance to constantly monitor the battery voltage Vb and generate an output signal when it reaches a predetermined voltage point b, which will be detailed later. There is.

TA is an automatic timer that receives the output signal from the voltage detector VD, automatically measures and announces the time, and various devices can be used, such as an analog recorder, a digital automatic timer with an interval timer, etc. It consists of a voltage recorder, etc., and a storage battery B.
The time interval from the discharge start time to the time when the predetermined voltage point b is reached is automatically measured and notified.

G. Effects of the present invention The present invention has the above-mentioned configuration.Next, we will discuss the operation mode and the effects. First, point a in the discharge characteristic of the voltage Vb of the storage battery B shown in FIG. 2 is as follows.
The input voltage to inverter IV at the start of discharge, which is the normal voltage VN, _T1 is the time when this input voltage is applied to point P in Figure 1, and point d is called the discharge end voltage of storage battery B. , indicates the lowest voltage at which the device itself will automatically stop due to a configuration not shown if the potential drops below this voltage. Point c is the switching voltage when the switching mechanism of the thyristor control circuit CN is operated, point b is the voltage that causes the voltage detector VD to generate an output signal, and _T2 is the time when the input voltage is applied to the point P. Indicates the time from T ₁ to the time when the output signal is generated, and the voltage at each point is determined by the storage battery B used.
Although it cannot be determined based on the characteristics of
Point a is 2.2 [V], point b is 1.85 [V], point c is 1.83
[V] and point d are set to about 1.8 [V], respectively.

Now, when the AC power is being transmitted normally, the state shown in Figure 1 is maintained, and DC power is being transmitted to the inverter IV that supplies power to the load L via the rectifier Rec, and the load L is not operating normally. ing.

To test the discharge of storage battery B in this state, operate the switching mechanism (not shown) of the thyristor control circuit CN to change the output of the rectifier Rec to the switching voltage VR.
That is, it is lowered to point c in FIG. Then, since the voltage becomes lower than the voltage of storage battery B, the storage battery starts discharging (normal voltage VN, ie, point a).

On the other hand, at the same time as this switching operation, the switch S is linked and closed, so the automatic timer TA is activated.
The operation start time T ₁ is recorded and the subsequent time is measured.

Discharging is continued in this state, and when the storage battery voltage Vb follows a gradual downward line and reaches point b, the voltage detector VD connected to the storage battery issues an output signal to the autotimer TA, so that the time Record T ₂ .

In this way, the automatic timer TA determines the time _T1 at which storage battery B starts discharging and the time _T2 at which it reaches the preset point b on the descending line traced during discharging, so that the time interval T between the two is determined. ₂ −T ₁ can be known,
By regularly conducting such discharge inspections,
In addition, since the power consumption of load L is approximately constant,
It is possible to accurately grasp the state of consumption of the storage battery B.

In addition, even if a defect occurs in a part (one cell) of storage battery B or a contact failure occurs in the storage battery terminal, etc., and the potential at point P drops rapidly as shown by dotted line e, Since the switching voltage VR (point c) is set higher than the discharge end voltage VS (point d), an approximately constant voltage continues to be supplied to the load L due to the automatic voltage adjustment function built into the inverter IV. No trouble occurs to the computer, etc., and the time T′ ₂ is set by the automatic timer TA.
Since the time interval is recorded, the shortening of the time interval can be known, and the presence of a defective storage battery can be determined.In this way, the discharge test of the storage battery can be easily and safely performed using the actual load of the operating uninterruptible device. Furthermore, since it can be operated completely automatically by using a separate program switch, etc., it is possible to provide a highly reliable uninterruptible device, and although it has a simple configuration, it can fully achieve the purpose of this project. Deliver excellent results.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing electrical connections according to an embodiment of the present invention, FIG. 2 shows discharge characteristics of a storage battery to explain the operation of the present invention, and FIG. 3 is a block diagram showing a conventional example. CN...Thyristor control circuit, S...Interlocked switch, TA...Auto timer, VD...Voltage detector.

Claims (1)

[Scope of utility model registration request] A rectifier Rec consisting of a thyristor or the like connected to an AC power supply, an inverter IV that operates in response to the output of the rectifier Rec for automatic voltage adjustment, a load L supplied with power from the inverter, one pole of which is grounded, and the other an accumulator B whose poles are connected to the output of said rectifier;
a voltage detector VD connected to the other pole to detect the discharge potential of the storage battery and issue a signal to the thyristor control circuit; , a thyristor control circuit CN having a built-in switching mechanism for lowering the electric potential of the power storage area below a predetermined potential point b, and an interlocking switching switch S interlocking with the signal of the auto-timer. In the thyristor control circuit, the switching mechanism switches the output voltage of the rectifier such that the discharge start potential of the storage battery is higher than the discharge end potential at point d and lower than the output signal generation potential of the detector at point b. A storage battery quality determination circuit in an uninterruptible device, characterized in that the circuit is configured as follows.