CN105203218A - Upper computer filtering method for generator temperature measuring system - Google Patents

Abstract

Provided is an upper computer filtering method for a generator temperature measuring system. The method is characterized by an upper computer recording temperature values with an interval of unit time T, and storing the temperature values to a queue C [N], the queue length being fixed to be N; placing new data sampled each time to the tail of the queue, and discarding the data at the head of the queue; and if refresh time of display temperature of a monitoring system is T', carrying out arithmetic average on the N data in the queue every an interval of T' to obtain a new filter value which is provided for the monitoring system to display and judge, wherein the setting of the T value is associated with required response speed of the temperature measuring system, and if the T is 1 s, the temperature values need to be recorded each second; the setting of the N value is associated with both the response speed of the system and the performance of filtering, the N value is neither too large nor too small, and the optimal setting of N meets the condition: N= T'/T; and the T' is the actual refresh time interval of the temperature values in the monitoring system. The upper computer filtering method for the generator temperature measuring system carries out filtering processing on the measured temperature signals, so that the response speed is guaranteed, and meanwhile, measuring error is reduced; and the method has the advantages of having a good interference suppression function and high smoothness and the like.

Description

A kind of host computer filtering method being applied to generator-temperature detection measuring system

Technical field

The present invention relates to generator-temperature detection measuring system, is a kind of host computer filtering method being applied to generator-temperature detection measuring system specifically.

Background technology

Generating plant temperature measurement system is by existing ground temperature measuring equipment, and local control unit LCU and host computer form.Temperature measuring equipment is generally temperature detecting resistance, as PT100 etc.Temperature divertor in local control unit LCU carries out the injection of electric current to temperature detecting resistance by generation constant current source, can be obtained the resistance of temperature detecting resistance, just calculate temperature value by resistance reduction formula afterwards by the voltage at measuring resistance two ends.Meanwhile, initial filter can also be carried out to signal, to reduce various interference to thermometric impact as far as possible.Finally, the signal be responsible for collecting by host computer shows, and checks for operator on duty.But, there is comparatively strong-electromagnetic field interference in power plant, particularly violent in electromagnetic field change, as: during electric braking, can there is larger fluctuation in measured temperature.Because the rate of load condensate of local control unit is higher, its rate of load condensate can be increased according to more complicated filtering algorithm, can have a negative impact to the control of the real-time monitoring of temperature and other equipment; Meanwhile, in power plant, the change of electromagnetic field sometimes and irregular, and simple filtering algorithm can well not play a role, so need a kind of method of shielding interference newly badly, when not affecting genset operational efficiency, improves thermometric accuracy.

The existing technology of temperature detecting resistance measuring tempeature that utilizes mainly contains: top-up injection method, electronic bridge measurement method etc., the temperature value of measurement can now utilize the equipment such as PLC to carry out simple filtering process.Prior art mainly contains two shortcomings: 1), the rate of load condensate of local control equipment is too high, affects the operational efficiency of equipment.2), due to the storage of local control equipment and computing power poor, the filtering algorithm that can provide is comparatively simple, cannot play inhibiting effect to many interference.

Summary of the invention

Because generator exists powerful electromagnetic field at run duration, tradition RTD thermometric loop is by the impact of the interference of electromagnetic field, there is the phenomenon of cyclic fluctuation in its temperature measured, for avoiding this kind of Special Errors, interference is produced to electricity generator monitoring system, filtering process need be carried out to measuring-signal, and utilize PLC to carry out filtering process now the rate of load condensate of supervisory system can be made significantly to increase, then the invention provides a kind of host computer filtering method being applied to generator-temperature detection measuring system, filtering process is carried out to the temperature signal measured, while taking into account response speed, reduce measuring error, have and have good inhibiting effect to interference, smoothness advantages of higher.

The technical solution adopted in the present invention is:

Be applied to a host computer filtering method for generator-temperature detection measuring system, step 1: host computer is with unit interval T for interval, and record temperature value, stored in queue C [N], queue length is fixed as N;

Step 2: the new data at every turn sampled is put into tail of the queue, and a data of head of the queue is thrown away;

Step 3: if the refresh time of supervisory system displays temperature is T ', then every the T ' time, carry out arithmetic mean, namely obtain new filter value to the N number of data in queue, is supplied to supervisory system display and judges;

Wherein, the setting of T value is relevant to the response speed needed for temp measuring system, if T is 1 second, then all needs p.s. to record temperature value; Namely the setting of N value is related to the response speed of system, simultaneously relevant to the performance of filtering, and N value is unsuitable excessive, also unsuitable too small, optimal design-aside N=T '/T; The actual refresh interval that T ' is temperature value in supervisory system.

Specific algorithm false code is described as:

Definition queue length N;

Definition queue C [N];

The computation complexity of this algorithm is O [N], and the array for storing data in algorithm can replace with chained list, and algorithm complex can suitably be optimized.

A kind of host computer filtering method being applied to generator-temperature detection measuring system of the present invention, technique effect is as follows:

1), at host computer realize filtering algorithm, be conducive to the rate of load condensate reducing local control unit, portable high.

2), while taking into account response speed, reduce measuring error, have and have good inhibiting effect, smoothness advantages of higher to interference.

3), the present invention propose in host computer, take moving average filter algorithm to come temperature signal filtering, the thinking adopting filtering algorithm in local control equipment different from the past.

Accompanying drawing explanation

Fig. 1 is temperature data comparison diagram before and after filtering in the embodiment of the present invention.

Embodiment

Be applied to a host computer filtering method for generator-temperature detection measuring system, step 1: host computer is with unit interval T for interval, and record temperature value, stored in queue C [N], queue length is fixed as N;

Step 2: the new data at every turn sampled is put into tail of the queue, and a data of head of the queue is thrown away;

Step 3: if the refresh time of supervisory system displays temperature is T ', then every the T ' time, carry out arithmetic mean, namely obtain new filter value to the N number of data in queue, is supplied to supervisory system display and judges;

Wherein, the setting of T value is relevant to the response speed needed for temp measuring system, if T is 1 second, then all needs p.s. to record temperature value; Namely the setting of N value is related to the response speed of system, simultaneously relevant to the performance of filtering, and N value is unsuitable excessive, also unsuitable too small, optimal design-aside N=T '/T; The actual refresh interval that T ' is temperature value in supervisory system.

Specific algorithm false code is described as:

Definition queue length N;

Definition queue C [N];

The computation complexity of this algorithm is O [N], and the array for storing data in algorithm can replace with chained list, and algorithm complex can suitably be optimized.

The present invention proposes in host computer, take moving average filter algorithm, utilizes the processing power of computing machine, plays high efficiency filter action, prevent from disturbing the measured temperature fluctuation problem caused.

Embodiment:

As shown in table 1, this temperature data is 100 groups of temperature datas of each 1 second, and Power Plant Monitoring setting carried out a Temperature displaying every 5 seconds, i.e. T=1, T '=5.Setting host computer algorithm queue length is 5, i.e. N=5.Due to T '=5, the displaying time of computer supervisory control system is followed successively by the 5th second, the 10th second, the 15th second ... before using filtering algorithm, the temperature data of display is: 27.7 DEG C, 33.5 DEG C, 27.5 DEG C ... and using the Temperature displaying value after algorithm for showing the running mean of moment front 5 time point data, then the display data after filtering algorithm are followed successively by: 29.9 DEG C, 31.9 DEG C, 29.6 DEG C ...

Table 1 power plant observed temperature data

27.6	33.9	29.1	31.3	27.7	32.0	28.6	32.5	32.9	33.5
										30.5	26.8	28.3	35.1	27.5	34.3	31.4	36.0	26.8	30.4
27.1	35.6	26.0	33.7	34.2	34.7	26.8	30.0	28.6	34.0
										30.3	35.1	27.8	28.6	27.5	27.4	34.7	31.8	31.5	27.4
34.5	32.2	29.5	31.1	30.0	26.8	28.4	27.2	27.8	28.4
										30.2	26.5	35.0	35.4	30.9	30.9	29.4	35.0	29.7	27.1
33.8	29.9	28.4	30.0	27.0	27.3	35.4	35.6	31.8	26.6
										28.3	29.5	34.2	26.2	26.4	27.7	32.5	33.3	32.5	30.5
31.5	29.0	33.4	27.9	32.9	27.8	29.7	32.3	33.8	26.8
										35.3	33.8	30.9	30.4	30.5	29.1	31.1	31.1	34.2	33.9

Fig. 1 shows the contrast of the Temperature displaying data before and after filtering, and fluctuation amplitude significantly reduces.

Claims (2)

1. be applied to a host computer filtering method for generator-temperature detection measuring system, it is characterized in that comprising the following steps:

Step 1: host computer is with unit interval T for interval, and record temperature value, stored in queue C [N], queue length is fixed as N;

Step 2: the new data at every turn sampled is put into tail of the queue, and a data of head of the queue is thrown away;

Step 3: if the refresh time of supervisory system displays temperature is T ', then every the T ' time, carry out arithmetic mean, namely obtain new filter value to the N number of data in queue, is supplied to supervisory system display and judges;

Wherein, the setting of T value is relevant to the response speed needed for temp measuring system, if T is 1 second, then all needs p.s. to record temperature value; Namely the setting of N value is related to the response speed of system, simultaneously relevant to the performance of filtering, and N value is unsuitable excessive, also unsuitable too small, optimal design-aside N=T '/T; The actual refresh interval that T ' is temperature value in supervisory system.

2. a moving average filter algorithm:

The computation complexity of this algorithm is O [N], and the array for storing data in algorithm can replace with chained list, and this algorithm application is in generator-temperature detection measuring system.