JPS6146391B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for controlling power consumption of an elevator.

Traditionally, buildings monitor the power demand for the entire building.
When the predicted 30-minute power demand is about to exceed the contract value, part of the load is cut off to make adjustments. Here, the power demand refers to the average power used within a certain period of time (generally 30 minutes).

On the other hand, the load inside the building naturally includes the elevator, and when the demand for power is about to exceed the contract value,
It is inevitable that the assigned value will change. However, when a plurality of elevators are installed, if one of the elevators is stopped, the operating efficiency of the elevators as a whole will drop significantly.

The present invention is intended to improve the above-mentioned problems, and an object of the present invention is to provide a power consumption control device for an elevator that is capable of operating within the required value when the required power demand value is changed.

An embodiment of the present invention will be described below with reference to FIGS. 1 to 5.

In Figure 1, 1-1 to 1-6 are car calls and landing calls for cars 1 to 6 (hereinafter simply referred to as calls);
2-1 to 2-6 are the car loads of Units 1 to 6,
3-1 to 3-6, 4-1 to 4-6, and 5 to 7 are calculation procedures, respectively.

Now, the power consumption of all elevators at time t ₁ is Pa
shall be. Next, assume that a start command is given to Unit 1 at this point. At this time, the driving direction and travel distance are calculated from the position of the car 1-1 and the current position of the car according to step 3-1. Furthermore, by knowing the car load 2-1, the power consumption _P1 required for this operation is predicted and calculated in step 4-1 as described later.
In this way, the power consumption amount at time _{t2 is predicted at time t1 ,} and the total P of the power consumption amounts _{P1 to P0 at} time t2 is calculated in step 5. Then, in step 7, compare this value with the required power amount determined from the power demand, and if the total amount of power consumption P is about to exceed the required value, extend the door opening time of Unit 1 and depart. delay.

Alternatively, in the case of power running operation (which can be determined by the load inside the car and the driving direction), the car is operated at a slightly lower speed. The above-mentioned door opening time and car speed are set so that the required power amount at time _t2 falls within the required value. The reason why the speed is reduced only during power running is that during regenerative operation, the power demand is reduced.

These circuits are omitted because they can be easily configured using well-known elevator control techniques.

The power consumption amount Pa may be a value actually measured using a wattmeter for each elevator, but generally a value calculated from the travel distance, car load, etc. is sufficient.

The required value Q of the demand power amount changes from Q to Q ₁ at time t = t ₁ .
Car operation can be controlled using the same calculations even when the system changes.

Next, with reference to FIGS. 2 to 5, a procedure for calculating power consumption from the driving direction, travel distance, and in-car load will be explained.

In the case of an elevator, acceleration, deceleration, and jerk (time derivative values of acceleration and deceleration) are calculated from riding comfort.
is decided.

Now, in Fig. 2, if the maximum acceleration is am, the maximum deceleration is bm, and the jerk is J, then ta=am/J Ta=V _O /am-am/J tb=bm/J Tb=V _O /bm -bm/J T=(S-S _O )/V _O where, ta: Time when acceleration changes tb: Time when deceleration changes Ta: Time when acceleration is constant Tb: Time when deceleration is constant T: Time to travel at a constant speed _VO : Rated speed, S: Travel distance from start to stop _S : Distance required for acceleration and deceleration, expressed by the formula below.

S _O =1/2 am ³ /J ² + /2Ta (am ² /J
+amTa) +( /2 am ² /J+amTa) am/J +1/2 bm ³ /J ² +1/2Tb (a ² m/J
+amTa) +(a ² m/J-1/2 bm ² /J+amTa) b
m/J Since the same calculation can be performed when the car does not reach the rated speed V _O , the details will be omitted.

The procedure for calculating the total amount of power P _o consumed during the above-mentioned times Ta, Tb, and T will be explained.

In Figures 3 to 5, 10 is a three-phase AC power supply, 11
is a thyristor converter that converts three-phase alternating current to direct current,
12 is the armature of the hoisting motor, 13 is the field magnet,
14 is a sheave driven by the armature 12, 15 is a main rope, 16 is a cage, 17 is a counterweight, 18 is a counterbalance rope that compensates for the weight difference due to the position of the main rope 15, and 19 is a tension on the counterbalance rope 18. 20 is a rectifier that supplies direct current to the field 13;
21 is a control circuit using a door drive motor (not shown) and a relay, I is the armature current, Ia is the armature current when accelerating at full load, I _O is the armature current when running at a constant speed, Ib is the armature current during deceleration regeneration, vd is the armature voltage, and p is the armature 12
p ₁ is the amount of power consumed by the field 13, and p ₂ is the amount of power consumed by the door and relay control circuit 21. Note that the broken line arrow in FIG. 3 indicates the direction of electric power regeneration, and the shaded area in FIG. 4 indicates the time of regenerative operation.

Now, the armature current I changes depending on the load within the car 16 as shown in FIG.

Therefore, considering the case when the full load is increased, the amount of power p consumed by the armature 12 is calculated by the following formula.

p=∫(I・vd+|I|V _O +p _O )dt Here, v _O : Forward voltage drop of the thyristor of the converter 11 p _O : Constant amount of power consumption by the converter 11 Note that vd is expressed by the following formula It is indicated by.

vd=KeV+IRa+vc Here, Ke: Power generation constant of armature 12 V: Speed of armature 12 Ra: Resistance of armature 21 vc: Voltage drop due to brush Also, armature current I varies during acceleration power running, constant speed running, and During deceleration regeneration, each is calculated as follows.

Ia=I _O +1/Kt・In/ram I _O =(WC・W _l )r/Kt Ib=I _O −1/Kt In/rbm Where, Kt: Torque constant of armature 12 In: Inertia Moment W: Load inside car 16 W _l : Rated capacity of car 16 C: Counterweight ratio (ratio of weight of counterweight 17 to rated capacity W _l ) r: Radius of sheave 14 Note that electric power p is positive and can take negative values.

Now, the total power consumption Pn of the n-th machine is Pn=(p+p ₁ +p ₂ ) _o . The total of this Pn for all machines is the first
This is the output of step 5 in the figure.

As explained above, in this invention, the amount of power consumed by the operation of the car is calculated, and this is compared with the amount of power determined from the predetermined power demand, and as a result, the predicted power consumption is determined to be the amount of power that is determined in advance. When it is determined that the car exceeds the required value, the car door is opened for an extended period of time or the car speed is reduced, so even if the required power demand changes, the car can be maintained within the required value without stopping the car. Can drive.

[Brief explanation of the drawing]

FIG. 1 is a calculation flowchart showing an embodiment of the elevator power consumption control device according to the present invention, FIG. 2 is an acceleration curve diagram and speed curve diagram of the elevator, and FIG. 3 is an explanatory diagram of each load of the elevator. 4 is an armature current curve diagram of FIG. 3, and FIG. 5 is an armature current curve diagram and an armature voltage curve diagram of FIG. 3. 1-1 to 1-6...Number of units 1 to 6, 2-
1 to 2-6...Load in the same left car, 3-1 to 3-6,
4-1 to 4-6, 5 to 7...Calculation procedures.

Claims (1)

[Scope of Claims] 1. A direction and distance calculation means for calculating the driving direction and traveling distance from the next stop position prior to starting the car and the current position of the car, and the calculation results of the direction and distance calculation means. and a first calculation device that predicts and calculates the power consumption associated with the operation of the car from the in-car load, and compares the power consumption related to the elevator determined from the predetermined power demand for the building with the predicted power consumption. A second arithmetic unit that performs calculations. When the second arithmetic unit performs a comparison calculation that indicates that the predicted power consumption exceeds the predetermined power consumption, the above-mentioned car A power consumption control device for an elevator comprising a door control circuit that extends the door opening time. 2. Direction and distance calculation means for calculating the driving direction and traveling distance from the next stop position and the current position of the car prior to starting the car, and from the calculation results of this direction and distance calculation means and the load in the car mentioned above. A first calculation device that predicts and calculates the amount of power consumed by the operation of the car, and a second calculation device that compares and calculates the amount of power related to the elevator determined from the power demand predetermined for the building and the predicted power consumption. when the second computing device determines from the computing results of the first computing device that the car is in power running and the predicted power consumption exceeds the power determined from the power demand; An elevator power consumption control device comprising a speed control circuit that reduces the speed of an elevator.