Load profiles

The load profiles can vary quite considerably, depending on the electrical users. For instance, for a factory the load will depend on the shift operation with a potential low demand at night and at weekends. The load can be influenced by seasonal changes. For instance, it may increase towards winter with greater lighting demands. However, the need for HVAC in computer installation... 

As with the electrical load profile, it is also necessary to analyze the heat load over the daily and annual cycles. Ideally, the heat load will match the available heat from the electrical generator (however, this is rarely the case). There will be periods when supplementary output will be necessary which can be achieved by, say, supplementary firing the waste heat gases of a gas turbine, or heat output reduction is necessary by the introduction of bypass stacks. For a steam turbine installation bypass pressure-reducing valves will be necessary to supplement steam output, while a dump condenser may be needed at low-process steam demands. The nature of the electrical and heat load will obviously have significant influence in the development of the scheme and scope of equipment. 

The load imposed upon the supply system will need to be analyzed for load profile, i.e. ... 

The connection of AA-size cells in parallel can replace larger cells (e.g., D-size cells). Four AA cells fit into a D-size can, and six AA-cells are in equivalent weight to a D-cell [27]. The utilization of the Mn02 cathode is considerably improved because the cathode thickness is only 2 mm in a AA cell, but 5 mm in a D-cell. The internal resistance is also lower by a factor of 4 to 6. Figure 11 depicts a 5 PxlO S bundle battery five AA cells in parallel = 1 bundle, 10 bundles in series make a (nominal) 12 V battery. It is used as the power source for a transmitter/receiver service. A typical load profile is 2 A for 1 min, 0.33 A for 9 min average load, 0.5 A per bundle or 0.1 A per cell service, about 15 h. Smaller bundle batteries (with 2x9 cells) are very suitable for notebook-computers 18 AA cells weight 0.36 kg, and the total initial capacity is 32 Wh. 

Sequencing Low/moderate (loading profile analysis) Very high High Robust High... 

Question 2 Is my equipment somehow responsible That is sadly often the case. For example, some electronic loads can show weird glitches in the load profile they present to the converter under dynamic conditions. For example, if we are doing step load testing from 10mA to 200mA, all may be fine. But if we go from 0mA to 200mA, and see an output overshoot/undershoot, it could also be because of the electronic load. We may need to do... 

In general, most converters are tested on the bench with the electronic load set to constant current (CC mode). True, that s not benign, nor as malignant as it gets. But the implied expectation is that converters should at least work in CC mode. They should, in particular, have no startup issues with this type of load profile. But even that may not be the end of the story Some loads can also vary with time. For example, an incandescent bulb has a resistive profile, but its cold resistance is much lower than its hot resistance. That s why most bulbs fail towards the end of their natural lifetime just when you throw the wall switch to its ON position. And if the converter is powering a system board characterized by sudden variations in its instantaneous supply current demand, that can cause severe problems to the converter, too. The best known example of this is an AC-DC power supply inside a computer. The 12V rail goes to the hard disk, which can suddenly demand very high currents as it spins up, and then lapse back equally suddenly into a lower current mode. 

Fig. 13 Contamination patterns identified (MCR-ALS resolved loading profiles) in the Ebro River delta from May to August 2005. On the left loadings in the second mode (normalized for variables to unit norm) describing the composition of the contamination patterns. Variable identification in Table 1. On the right loadings in the first and third modes (mixed) describing spatial and temporal distribution of the contamination patterns. Sampling sites ordered from North to South, for the four analyzed months displayed consecutively (May 1-11 June 12-22 July 23-33 August 34 4)...

Power-monitoring software can be used to analyze energy use and power quality. It can identify load profiles to help with rate negotiation. If companies know their energy profiles, how and when they consume power, they can negotiate better rates for the type and amount of power they need. 

Linking power management systems to control systems allows the power information to flow from both systems. Load profiles can be developed to find any energy inefficiencies. Energy scheduling can be used to find the optimum energy schedule for new product lines or processes. 

What will the expected electricity demand be, and depending on type and pattern of charging, what will the corresponding load profile look like, as this affects grid management ... 

In the case of almost continuous signals such as voltammograms, it may be useful to represent the loading profiles, eventually superimposed... 

The Presster is a single-station press that can mimic the load profile of any production press. The IVesster uses mechanical means to achieve geometric similarity with different tablet presses. Kinematic and dynamic similarities are achieved by matching the speed and force of compression. The process parameters for both press simulations are indicated in Table 4. 

Catalyst quality on a mesoscopic length scale (diffusion length, loading, profiles)... 

Patent for MBPC design used in peak-shedding applications to predict loads based on extended load profiles. 

The maximum conversion, the corresponding amount of product, optimal constant reflux ratio and heat load profiles for different batch times are shown in Figures 9.3-9.6. The maximum conversion profile achieved under total reflux operation (where no product is withdrawn) is also shown in Figure 9.3. The latter approximates the conversion which would be achieved in the absence of distillation. Note that if there is a large column holdup, the conversion under total reflux will not approximate the conversion achieved in the absence of distillation. 

FIGURE 11.19 Composition (loading) profiles of resolved components in the MCR-ALS analysis of raw augmented data matrix. Top components explain more variance bottom components explain less variance. Names for the compounds are defined in the caption to Figure 11.17. 

Load Profile. The load profile used to simulate the proposed SHES reflects typical residential electricity needs in a remote (off-grid) application. In order to meet the requirements of the consumer load, the SHES must provide 58 kWh of AC electricity each day of the year, at 120 V and 60 Hz. The peak load each day is 10 kW, which occurs in the early evening, and the daily average load is 2.5 kW. The daily, peak, and average loads that the SHES system must supply also take into account losses encountered in AC/DC power inversion, DC/DC voltage conversion, and power requirements of various system components (i.e. controller). 

Figure 5.5. Daily electric load profile of Fair Isle...

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