Capacitance compensation issues? What about the consequences of capacitor compensation overcompensat

1 Then high-voltage capacitors are rare Capacitors generally play the role of voltage boost! 2 Use a multimeter to pick up the resistor to measure the resistance, if it is a way unchanged, it means that the capacitor is short-circuited or the capacitor breaks down If the capacitance resistance changes from small to large, it means that the capacitance is good The capacitor can be neutralized and discharged The positive electrode can also be discharged to the ground 3 The connection of the capacitor is like that Boost 4 The power is related to the carrying capacity of the wire and the energy required, if you need a large power, it will be larger If the power is smaller, as long as the equipment is running normally, everything is suitable and safe!

I add. 1.The reactive power compensation capacity can be estimated at 15%-25% of the transformer capacity.

2.Use the multimeter resistance level to measure the capacitance, and the resistance will become small and large. Explain that the capacitance is good.

If the time from small to large is short, it means that the capacitance capacity is small. If the time is long, it means that the capacitance is large. 3.

I didn't understand your question. 4.The power supply company requires the power factor of the low-voltage distribution system of the factory to reach the above, otherwise it will pay a certain percentage of the fine.

1. The capacitor compensation capacity is best compensated on the spot, calculated according to 15%-30% of the capacity of the main transformer 2. The capacitor bank is equipped with a discharge coil to protect the capacitor 3. The capacitor assembly method is parallel 4. The power factor reaches the above, the voltage quality is qualified and the harmonic problem is eliminated.

4. The closer the power factor is to 1, the better, when the load of the same power is supplied with power, the smaller the power factor, the larger the current, the greater the line voltage drop and the power loss, so the economy is poor. Electrical energy = (voltage, current, power factor 1000) usage time. Therefore, the power supply company requires the power factor of the user to reduce the line loss and improve the electric energy.

The hazards of overcompensation.

1. It is easy to form resonance phenomenon.

2. Raise the network voltage.

3. Increase active power loss.

4. Reactive power reverse, like forward feeding, will produce voltage loss δu and active power loss δp.

5. Overcompensate the excess reactive power ΔQC to produce active loss.

Precautionary measures. 1. The reactive power compensation shunt capacitor adopts an automatic switching device.

2. The total compensation capacity should be limited in the design and installation, and the monitoring should be strengthened in operation.

3. Establish a set of effective reactive power compensation capacitor operation procedures or operation duty system.

What is the normal range for capacitance compensation? What is the normal range of capacitance compensation1. The capacitance current requirement of undercompensation compensation is less than the offset inductance current. After compensation, there is still a certain amount of inductive reactive current, so that the COS is less than 1 but close to full compensation and the capacitor is configured according to the inductive actual load current, IC=IL will cancel out all the capacitive current of the inductive current, so that the COS is equal to overcompensate a large amount of input capacitor, after all the inductance current is offset, there is still a part of the capacitive current, and the original inductive load is converted into a capacitive load property.

The power factor cos is still less than 1. The basic principle of compensation is that the undercompensation method must be used, and the power factor after compensation is required to be less than 1 and as close to 1 as possible. In order to prevent resonance, the upper limit is generally set at.

For a load with a capacity of 700 kW, you can first measure the natural power factor, which is the power factor value without capacitors when the load is started. If there is no way to accurately measure, it is estimated that most of your load is a motor, estimated by the power factor cos 1=, to increase its power factor to in the rated state, you need to compensate the capacitor capacity as: before compensation:

cos 1=, 1=, tg 1= after compensation: cos 2=, 2=, tg 2= rounded, about 378kvar capacitors need to be compensated, if a single 14kvar capacitor bank is selected, 27 pieces are needed. Do you understand this explanation?

Capacitance compensationIt is reactive power compensation or power factor compensation.

The electrical equipment of the power system will produce reactive power when used, and it is usually inductive, which will reduce the capacity use efficiency of the power supply, which can be improved by increasing the capacitance appropriately in the system.

Power capacitance compensation is also known as power factor compensation. Generally speaking, the low-voltage capacitance compensation cabinet is composed of cabinet shells, busbars, circuit breakers, isolation switches, thermal relays, contactors, lightning arresters, capacitors, reactors, primary and secondary wires, terminal strips, power factor automatic compensation control devices, disk instruments, etc.

Capacitance Compensation Method:

1.Local compensation Local compensation is to connect the low-voltage capacitor bank with the motor in parallel, and switch it with the motor at the same time through the control and protection device. Random compensation is suitable for compensating the reactive power consumption of the motor, mainly to compensate for magnetic reactive power, which can effectively reduce the current of the switch and cable loop, and appropriately reduce the burden of the switch and cable.

The advantages of local compensation are: when the electrical equipment is running, the reactive power compensation input, when the electrical equipment is out of operation, the compensation equipment is also withdrawn, and the compensation capacity does not need to be adjusted frequently. It has the characteristics of low investment, small footprint, easy installation, convenient and flexible configuration, simple maintenance and low accident rate.

2.Follow-up compensation refers to the compensation method of connecting the low-voltage capacitor to the secondary side of the distribution transformer through the low-voltage fuse to compensate the no-load reactive power of the distribution transformer. The reactive load of the distribution transformer at light load or no-load is mainly the no-load excitation reactive power of the transformer, and the no-load reactive power of the distribution transformer is the main part of the reactive power load of the rural grid.

The advantages of random device compensation are: simple wiring, convenient maintenance and management, can effectively compensate for the no-load reactive power of the distribution transformer, limit the reactive base load of the power grid, and balance the reactive power of this part on the spot, so as to improve the utilization rate of the distribution transformer, reduce the reactive power network loss, have high economy, and are one of the most effective means to compensate for reactive power at present.

3.Centralized tracking compensation Centralized tracking compensation refers to the compensation method of using the reactive power compensation switching device as the control and protection device to compensate the low-voltage capacitor bank on the bus of large users. It is suitable for special distribution and transformation users of more than 100kVA, and can replace the two compensation methods of local and follower, and the compensation effect is good.

The advantages of tracking compensation are: flexible operation mode, small operation and maintenance workload, relatively longer life and more reliable operation than the first two compensation methods. However, the disadvantage is that the control and protection device is complex and the initial investment is relatively large.

However, when the economics of these three compensation methods are similar, the centralized tracking compensation method should be preferred.

There are many types of capacitors, and different types of capacitors have different functions. In the first air conditioning system, electrolytic capacitors are often used as filtering elements in the control circuit, and non-polar capacitors are connected in series in the windings of the compressor (single-phase asynchronous) motor, so that the motor starting winding is at a phase angle when starting, and the current leads the operation to exceed the starting current by one phase angle, so as to obtain the starting torque and make the motor easy to start.

This is generally the use of active power, apparent power COS reactive power compensation capacitor function should start from reactive power.

The words are like this:

A part of the energy of the power is used to establish the magnetic field, which is used as exchange energy, and does not do work on external circuits, they are converted from electrical energy to magnetic field energy, and then converted from magnetic field energy to electrical energy, and the cycle is repeated, and it is not consumed, this part of the energy is called reactive power. Reactive power is not useless work, without this part of the power, the induced magnetic field cannot be established, and the motor, transformer and other equipment cannot operate. In addition to the load needs reactive power, line inductance, transformer inductance, etc. are also required.

The specific benefits are many, many more:

Just name a few!

After compensating for reactive power, it can increase voltage, reduce line loss, reduce electricity expenses, save energy, increase the transmission of active capacity of the power grid, and improve the efficiency of equipment

Anti-higher harmonic resonance reactors, capacitors and possible higher harmonic resonances of inductors in the system. Improves switching performance and acts as a current limiting when a capacitor is fed.

Improves the power factor. Protection against higher harmonics, possible higher harmonic resonances of capacitors and inductors in the system. Improves switching performance and acts as a current limiting when a capacitor is fed.

Storing electric energy, releasing it instantly, reducing reactive power loss on the line and improving the power factor.

1. Improve the active power of the power grid.

2. Reduce line energy loss.

3. Improve the power supply capacity of the system.

4. Reduce the voltage drop of the line and improve the voltage quality of the power grid.